* [PATCHv4 01/18] thermal: allow registering without .get_temp
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 02/18] thermal: core: allow binding via .bind when tzp is present Eduardo Valentin
` (13 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin
This patch changes the thermal core driver to allow
registration of thermal zones without the .get_temp callback.
The idea behind this change is to allow lazy registration
of sensor callbacks.
The thermal zone will be disabled whenever the ops
does not contain a .get_temp callback. The sysfs interface
will be returning -EINVAL on any temperature read operation.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
drivers/thermal/thermal_core.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 4962a6a..8a94300 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -402,7 +402,7 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
enum thermal_trip_type type;
#endif
- if (!tz || IS_ERR(tz))
+ if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
goto exit;
mutex_lock(&tz->lock);
@@ -455,6 +455,9 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
{
int count;
+ if (!tz->ops->get_temp)
+ return;
+
update_temperature(tz);
for (count = 0; count < tz->trips; count++)
@@ -1384,7 +1387,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
return ERR_PTR(-EINVAL);
- if (!ops || !ops->get_temp)
+ if (!ops)
return ERR_PTR(-EINVAL);
if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
@@ -1488,6 +1491,9 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
+ if (!tz->ops->get_temp)
+ thermal_zone_device_set_polling(tz, 0);
+
thermal_zone_device_update(tz);
if (!result)
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 02/18] thermal: core: allow binding via .bind when tzp is present
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 01/18] thermal: allow registering without .get_temp Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-11-06 2:56 ` Wei Ni
2013-09-27 3:13 ` [PATCHv7 03/18] thermal: introduce device tree parser Eduardo Valentin
` (12 subsequent siblings)
14 siblings, 1 reply; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin
This patch allows drivers register thermal zone devices
with thermal zone params and .bind callbacks. In this case,
it will use the .bind callback.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
drivers/thermal/thermal_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 8a94300..f7a9f4f 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -247,7 +247,7 @@ static void bind_cdev(struct thermal_cooling_device *cdev)
if (!pos->tzp && !pos->ops->bind)
continue;
- if (!pos->tzp && pos->ops->bind) {
+ if (pos->ops->bind) {
ret = pos->ops->bind(pos, cdev);
if (ret)
print_bind_err_msg(pos, cdev, ret);
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* Re: [PATCHv4 02/18] thermal: core: allow binding via .bind when tzp is present
2013-09-27 3:13 ` [PATCHv4 02/18] thermal: core: allow binding via .bind when tzp is present Eduardo Valentin
@ 2013-11-06 2:56 ` Wei Ni
0 siblings, 0 replies; 31+ messages in thread
From: Wei Ni @ 2013-11-06 2:56 UTC (permalink / raw)
To: Eduardo Valentin, swarren@wwwdotorg.org, pawel.moll@arm.com,
mark.rutland@arm.com, ian.campbell@citrix.com,
rob.herring@calxeda.com, linux@roeck-us.net, rui.zhang@intel.com
Cc: grant.likely@linaro.org, durgadoss.r@intel.com,
linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org
On 09/27/2013 11:13 AM, Eduardo Valentin wrote:
> This patch allows drivers register thermal zone devices
> with thermal zone params and .bind callbacks. In this case,
> it will use the .bind callback.
>
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
> ---
> drivers/thermal/thermal_core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 8a94300..f7a9f4f 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -247,7 +247,7 @@ static void bind_cdev(struct thermal_cooling_device *cdev)
> if (!pos->tzp && !pos->ops->bind)
> continue;
>
> - if (!pos->tzp && pos->ops->bind) {
> + if (pos->ops->bind) {
Hi, Eduardo
In bind_tz() routine, it also has same problem.
I had sent out similar patch "[PATCHv4 02/18] thermal: core: allow
binding via .bind when tzp is present" to fix it, but no response yet.
I think you can add my changes in your series :)
Thanks.
Wei.
> ret = pos->ops->bind(pos, cdev);
> if (ret)
> print_bind_err_msg(pos, cdev, ret);
>
^ permalink raw reply [flat|nested] 31+ messages in thread
* [PATCHv7 03/18] thermal: introduce device tree parser
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 01/18] thermal: allow registering without .get_temp Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 02/18] thermal: core: allow binding via .bind when tzp is present Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-30 15:36 ` Mark Rutland
[not found] ` <1380251605-3804-4-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
2013-09-27 3:13 ` [PATCHv4 05/18] thermal: cpu_cooling: introduce of_cpufreq_cooling_register Eduardo Valentin
` (11 subsequent siblings)
14 siblings, 2 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin
This patch introduces a device tree bindings for
describing the hardware thermal behavior and limits.
Also a parser to read and interpret the data and feed
it in the thermal framework is presented.
This patch introduces a thermal data parser for device
tree. The parsed data is used to build thermal zones
and thermal binding parameters. The output data
can then be used to deploy thermal policies.
This patch adds also documentation regarding this
API and how to define tree nodes to use
this infrastructure.
Note that, in order to be able to have control
on the sensor registration on the DT thermal zone,
it was required to allow changing the thermal zone
.get_temp callback. For this reason, this patch
also removes the 'const' modifier from the .ops
field of thermal zone devices.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
Hello folks,
For those interested on this work, here is a short changelog from v6:
- Reviewed binding documentation and added type and size on all properties
- Described 'thermal-zones' node in binding documentation
- Using now cooling state terminology instead of cooling level
- Renamed milliCelsius to millicelsius
- Renamed cooling-attachments to 'cooling-maps'
- Renamed sensor to thermal sensor
- Renamed #sensor-cells to #thermal-sensor-cells
- #thermal-sensor-cells now is allowed to be 0
- Renamed 'sensors' property to 'thermal-sensors'
- Changed trip type property to be now string and documented possible values
- Described better the cooling properties
- Now parses 'contribution' instead of 'usage'
- Renamed cdev to cooling device
- Renamed 'passive-delay' property to 'polling-delay-passive'
- Fixed a couple of error messages to match the property name
- Fixed a binding issue while using cpufreq as module
- Reworked thermal_of_build_thermal_zone function so that it frees
requested memory if something goes wrong and checks for sub-nodes
with zero children.
---
.../devicetree/bindings/thermal/thermal.txt | 537 +++++++++++++
drivers/thermal/Kconfig | 13 +
drivers/thermal/Makefile | 1 +
drivers/thermal/of-thermal.c | 845 +++++++++++++++++++++
drivers/thermal/thermal_core.c | 9 +-
drivers/thermal/thermal_core.h | 9 +
include/dt-bindings/thermal/thermal.h | 27 +
include/linux/thermal.h | 28 +-
8 files changed, 1466 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
create mode 100644 drivers/thermal/of-thermal.c
create mode 100644 include/dt-bindings/thermal/thermal.h
diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
new file mode 100644
index 0000000..3dbc017
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/thermal.txt
@@ -0,0 +1,537 @@
+* Thermal Framework Device Tree descriptor
+
+Generic binding to provide a way of defining hardware thermal
+structure using device tree. A thermal structure includes thermal
+zones and their components, such as trip points, polling intervals,
+sensors and cooling devices binding descriptors.
+
+The target of device tree thermal descriptors is to describe only
+the hardware thermal aspects, not how the system must control or which
+algorithm or policy must be taken in place.
+
+There are five types of nodes involved to describe thermal bindings:
+- sensors: used to describe the device source of temperature sensing;
+- cooling devices: used to describe devices source of power dissipation control;
+- trip points: used to describe points in temperature domain defined to
+make the system aware of hardware limits;
+- cooling maps: used to describe links between trip points and
+cooling devices;
+- thermal zones: used to describe thermal data within the hardware;
+
+It follows a description of each type of these device tree nodes.
+
+Note: This binding is a working in progress.
+
+* Thermal sensor devices
+
+Thermal sensor devices are nodes providing temperature sensing capabilities on
+thermal zones. Typical devices are I2C ADC converters and bandgaps. Theses are
+nodes providing temperature data to thermal zones. Thermal sensor devices may
+control one or more internal sensors.
+
+Required property:
+- #thermal-sensor-cells: Used to provide sensor device specific information
+ Type: unsigned while referring to it. Typically 0, on thermal sensor
+ Size: one cell nodes with only one sensor, and at least 1 on nodes
+ with several internal sensors, in order
+ to identify uniquely the sensor instances within
+ the IC. See thermal zone binding for more details
+ on how consumers refer to sensor devices.
+
+* Cooling device nodes
+
+Cooling devices are nodes providing control on power dissipation. There
+are essentially two ways to provide control on power dissipation. First
+is by means of regulating device performance, which is known as passive
+cooling. A typical passive cooling is a CPU that has dynamic voltage and
+frequency scaling, and uses lower frequencies as cooling states.
+Second is by means of activating devices in order to remove
+the dissipated heat, which is known as active cooling, e.g. regulating
+fan speeds. In both cases, cooling devices shall have a way to determine
+the state of cooling in which the device is.
+
+Required property:
+- cooling-min-state: An integer indicating the smallest
+ Type: unsigned cooling state accepted. Typically 0.
+ Size: one cell
+
+- cooling-max-state: An integer indicating the largest
+ Type: unsigned cooling state accepted.
+ Size: one cell
+
+- #cooling-cells: Used to provide cooling device specific information
+ Type: unsigned while referring to it. Must be at least 2, in order
+ Size: one cell to specify minimum and maximum cooling state used
+ in the reference. The first cell is the minimum
+ cooling state requested and the second cell is
+ the maximum cooling state requested in the reference.
+ See Cooling device maps section below for more details
+ on how consumers refer to cooling devices.
+
+* Trip points
+
+The trip node is a node to describe a point in the temperature domain
+in which the system takes an action. This node describes just the point,
+not the action.
+
+Required properties:
+- temperature: An integer indicating the trip temperature level,
+ Type: signed in millicelsius.
+ Size: one cell
+
+- hysteresis: a (low) hysteresis value on 'temperature'. This is a
+ Type: unsigned relative value, in millicelsius.
+ Size: one cell
+
+- type: a string containing the trip type. Supported values are:
+ "active": A trip point to enable active cooling
+ "passive": A trip point to enable passive cooling
+ "hot": A trip point to notify emergency
+ "critical": Hardware not reliable.
+ Type: string
+
+There are also string constants defined at
+include/dt-bindings/thermal/thermal.h.
+
+* Cooling device maps
+
+The cooling device maps node is a node to describe how cooling devices
+get assigned to trip points of the zone. The cooling devices are expected
+to be loaded in the target system.
+
+Required properties:
+- cooling-device: A phandle of a cooling device with its specifier,
+ Type: phandle referring to which cooling device is used in this
+ binding. The required specifiers are: the minimum
+ cooling state and the maximum cooling level used
+ in this map.
+- trip: A phandle of a trip point node within the same thermal
+ Type: phandle zone.
+
+Optional property:
+- contribution: The cooling contribution to the thermal zone of the
+ Type: unsigned referred cooling device at the referred trip point.
+ Size: one cell The contribution is a ratio of the sum
+ of all cooling contributions within a thermal zone.
+
+Note: Using the THERMAL_NO_LIMIT (-1L) constant in the cooling-device phandle
+limit specifier means:
+(i) - minimum state allowed for minimum cooling level used in the reference.
+(ii) - maximum state allowed for maximum cooling level used in the reference.
+Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
+
+* Thermal zone nodes
+
+The thermal zone node is the node containing all the required info
+for describing a thermal zone, including its cooling device bindings. The
+thermal zone node must contain, apart from its own properties, one node containing
+trip nodes and one node containing all the zone cooling maps.
+
+Required properties:
+- polling-delay-passive: The maximum number of milliseconds to wait
+ Type: unsigned between polls when performing passive cooling.
+ Size: one cell
+
+- polling-delay: The maximum number of milliseconds to wait between polls
+ Type: unsigned when checking this thermal zone.
+ Size: one cell
+
+- thermal-sensors: A list of sensor phandles and sensor specifier
+ Type: list of phandles used while monitoring the thermal zone.
+
+- trips: A sub-node which is a container of only trip point nodes
+ Type: sub-node required to describe the thermal zone.
+
+- cooling-maps: A sub-node which is a container of only cooling device
+ Type: sub-node map nodes, used to describe the relation between trips
+ and cooling devices.
+
+Optional property:
+- thermal-sensors-names: List of thermal sensor name strings sorted
+ Type: list of strings in the same order as the thermal-sensors
+ property.
+
+- coefficients: An array of integers (one signed cell) containing
+ Type: array coefficients to compose a linear relation between
+ Elem size: one cell the sensors described in the thermal-sensors property.
+ Elem type: signed Coefficients defaults to 1, in case this property
+ is not specified. A simple linear polynomial is used:
+ Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
+
+ The coefficients are ordered and they match with sensors
+ by means of sensor ID. Additional coefficients are
+ interpreted as constant offsets.
+
+Note: The delay properties are bound to the maximum dT/dt (temperature
+derivative over time) in two situations for a thermal zone:
+(i) - when active cooling is activated (polling-delay-passive); and
+(ii) - when the zone just needs to be monitored (polling-delay).
+The maximum dT/dt is highly bound to hardware power consumption and dissipation
+capability.
+The delays are chosen to account for said max dT/dt, such that a device
+does not cross several trip boundaries unexpectedly between polls. Choosing
+the right polling delays shall avoid having the device in temperature ranges
+that may damage the silicon structures and reduce silicon lifetime.
+
+* The thermal-zones node
+
+The "thermal-zones" node is a container for all thermal zone nodes. It shall
+contain only sub-nodes describing thermal zones as in the section
+"Thermal zone nodes".
+
+* Examples
+
+Below are several examples on how to use thermal data descriptors
+using device tree bindings:
+
+(a) - CPU thermal zone
+
+The CPU thermal zone example below describes how to setup one thermal zone
+using one single sensor as temperature source and many cooling devices and
+power dissipation control sources.
+
+#include <dt-bindings/thermal/thermal.h>
+
+cpus {
+ cpu0: cpu@0 {
+ ...
+ cooling-min-state = <0>;
+ cooling-max-state = <3>;
+ #cooling-cells = <2>; /* min followed by max */
+ };
+ ...
+};
+
+&i2c1 {
+ ...
+ fan0: fan@0x48 {
+ ...
+ cooling-min-state = <0>;
+ cooling-max-state = <9>;
+ #cooling-cells = <2>; /* min followed by max */
+ };
+};
+
+bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <0>;
+};
+
+cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0>;
+
+ trips {
+ cpu-alert0: cpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_ACTIVE;
+ };
+ cpu-alert1: cpu-alert {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ cpu-crit: cpu-crit {
+ temperature = <125000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&cpu-alert0>;
+ cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
+ };
+ map1 {
+ trip = <&cpu-alert1>;
+ cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
+ };
+ map2 {
+ trip = <&cpu-alert1>;
+ cooling-device =
+ <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
+ };
+ };
+};
+
+In the example above, the ADC sensor at address 0x0000ED00 is used to monitor
+the zone 'cpu-thermal' using its the sensor 0. The fan0, a fan device controlled
+via I2C bus 1, at adress 0x48, which has ten different cooling states.
+It is used to remove the heat out of the thermal zone 'cpu-thermal' using its
+cooling states from its minimum to 4, when it reaches trip point 'cpu-alert0'
+at 90C, as an example of active cooling. The same cooling device is used at
+'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
+linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
+using all its cooling states at trip point 'cpu-alert1',
+which is a trip point at 100C.
+
+(b) - IC with several internal sensors
+
+The example below describes how to deploy several thermal zones based off a
+single sensor IC, assuming it has several internal sensors. This is a common
+case on SoC designs with several internal IPs that may need different thermal
+requirements, and thus may have their own sensor to monitor or detect internal
+hotspots in their silicon.
+
+#include <dt-bindings/thermal/thermal.h>
+
+bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <1>;
+};
+
+cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 0>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ cpu-alert: cpu-alert {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ cpu-crit: cpu-crit {
+ temperature = <125000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+};
+
+gpu-thermal: gpu-thermal {
+ polling-delay-passive = <120>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 1>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ gpu-alert: gpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ gpu-crit: gpu-crit {
+ temperature = <105000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+};
+
+dsp-thermal: dsp-thermal {
+ polling-delay-passive = <50>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 2>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ dsp-alert: gpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ dsp-crit: gpu-crit {
+ temperature = <135000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+};
+
+In the example above there is one bandgap IC which has the capability to
+monitor three sensors. The hardware has been designed so that sensors are
+placed on different places in the DIE to monitor different temperature
+hotspots: one for CPU thermal zone, one for GPU thermal zone and the
+other to monitor a DSP thermal zone.
+
+Thus, there is a need to assign each sensor provided by the bandgap IC
+to different thermal zones. This is achieved by means of using the
+#thermal-sensor-cells property and using the first specifier as sensor ID.
+In the example, then, bandgap.sensor0 is used to monitor CPU thermal zone,
+bandgap.sensor1 is used to monitor GPU thermal zone and bandgap.sensor2
+is used to monitor DSP thermal zone. Each zone may be uncorrelated,
+having its own dT/dt requirements, trips and cooling maps.
+
+
+(c) - Several sensors within one single thermal zone
+
+The example below illustrates how to use more than one sensor within
+one thermal zone.
+
+#include <dt-bindings/thermal/thermal.h>
+
+&i2c1 {
+ ...
+ adc: sensor@0x49 {
+ ...
+ #thermal-sensor-cells = <0>;
+ };
+};
+
+bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <0>;
+};
+
+cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0>,
+ <&adc>;
+ thermal-sensors-names = "cpu", "pcb north";
+
+ /* hotspot = 100 * bandgap - 120 * adc + 484 */
+ coefficients = <100 -120 484>;
+
+ trips {
+ ...
+ };
+
+ cooling-maps {
+ ...
+ };
+};
+
+In some cases, there is a need to use more than one sensor to extrapolate
+a thermal hotspot in the silicon. The above example illustrate this situation.
+For instance, it may be the case that a sensor external to CPU IP may be place
+close to CPU hotspot and together with internal CPU sensor, it is used
+to determine the hotspot. The hyppotetical extrapolation rule would be:
+ hotspot = 100 * bandgap - 120 * adc + 484
+
+The same idea can be used to add fixed offset:
+ polling-delay-passive = <1000>; /* milliseconds */
+ polling-delay = <2500>; /* milliseconds */
+ hotspot = 1 * adc + 6000
+
+In the above equation, the hotspot is always 6C higher than what is read
+from the sensor ADC. The binding would be then:
+ /* sensor ID */
+ thermal-sensors = <&adc 0>;
+
+ /* hotspot = 1 * adc + 6000 */
+ coefficients = <1 6000>;
+
+(d) - Board thermal
+
+The board thermal example below illustrates how to setup one thermal zone
+with many sensors and many cooling devices.
+
+#include <dt-bindings/thermal/thermal.h>
+
+&i2c1 {
+ ...
+ adc-dummy: sensor@0x50 {
+ ...
+ #thermal-sensor-cells = <1>; /* sensor internal ID */
+ };
+};
+
+batt-thermal {
+ polling-delay-passive = <500>; /* milliseconds */
+ polling-delay = <2500>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&adc-dummy 4>;
+
+ trips {
+ ...
+ };
+
+ cooling-maps {
+ ...
+ };
+};
+
+board-thermal: board-thermal {
+ polling-delay-passive = <1000>; /* milliseconds */
+ polling-delay = <2500>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&adc-dummy 0>,
+ <&adc-dummy 1>,
+ <&adc-dymmy 2>;
+ thermal-sensors-names = "pcb top edge", "lcd", "back cover";
+ /*
+ * An array of coefficients describing the sensor
+ * linear relation. E.g.:
+ * z = c1*x1 + c2*x2 + c3*x3
+ */
+ coefficients = <1200 -345 890>;
+
+ trips {
+ /* Trips are based on resulting linear equation */
+ cpu-trip: cpu-trip {
+ temperature = <60000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ gpu-trip: gpu-trip {
+ temperature = <55000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ }
+ lcd-trip: lcp-trip {
+ temperature = <53000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ crit-trip: crit-trip {
+ temperature = <68000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&cpu-trip>;
+ cooling-device = <&cpu0 0 2>;
+ contribution = <55>;
+ };
+ map1 {
+ trip = <&gpu-trip>;
+ cooling-device = <&gpu0 0 2>;
+ contribution = <20>;
+ };
+ map2 {
+ trip = <&lcd-trip>;
+ cooling-device = <&lcd0 5 10>;
+ contribution = <15>;
+ };
+ };
+};
+
+The above example is a mix of previous examples, a sensor IP with several internal
+sensors used to monitor different zones, one of them is composed by several sensors and
+with different cooling devices.
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index dbfc390..dd81eb8 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -29,6 +29,19 @@ config THERMAL_HWMON
Say 'Y' here if you want all thermal sensors to
have hwmon sysfs interface too.
+config THERMAL_OF
+ bool
+ prompt "APIs to parse thermal data out of device tree"
+ depends on OF
+ default y
+ help
+ This options provides helpers to add the support to
+ read and parse thermal data definitions out of the
+ device tree blob.
+
+ Say 'Y' here if you need to build thermal infrastructure
+ based on device tree.
+
choice
prompt "Default Thermal governor"
default THERMAL_DEFAULT_GOV_STEP_WISE
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 584b363..4b03956 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -7,6 +7,7 @@ thermal_sys-y += thermal_core.o
# interface to/from other layers providing sensors
thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
+thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
# governors
thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
new file mode 100644
index 0000000..0464eaf
--- /dev/null
+++ b/drivers/thermal/of-thermal.c
@@ -0,0 +1,845 @@
+/*
+ * of-thermal.c - Generic Thermal Management device tree support.
+ *
+ * Copyright (C) 2013 Texas Instruments
+ * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#include <linux/thermal.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/string.h>
+
+#include "thermal_core.h"
+
+/*** Private data structures to represent thermal device tree data ***/
+
+/**
+ * struct __thermal_trip - representation of a point in temperature domain
+ * @np: pointer to struct device_node that this trip point was created from
+ * @temperature: temperature value in miliCelsius
+ * @hysteresis: relative hysteresis in miliCelsius
+ * @type: trip point type
+ */
+
+struct __thermal_trip {
+ struct device_node *np;
+ unsigned long int temperature;
+ unsigned long int hysteresis;
+ enum thermal_trip_type type;
+};
+
+/**
+ * struct __thermal_bind_param - a match between trip and cooling device
+ * @cooling_device: a pointer to identify the referred cooling device
+ * @trip_id: the trip point index
+ * @usage: the percentage (from 0 to 100) of cooling contribution
+ * @min: minimum cooling state used at this trip point
+ * @max: maximum cooling state used at this trip point
+ */
+
+struct __thermal_bind_params {
+ struct device_node *cooling_device;
+ unsigned int trip_id;
+ unsigned int usage;
+ unsigned long min;
+ unsigned long max;
+};
+
+/**
+ * struct __thermal_zone - internal representation of a thermal zone
+ * @mode: current thermal zone device mode (enabled/disabled)
+ * @passive_delay: polling interval while passive cooling is activated
+ * @polling_delay: zone polling interval
+ * @ntrips: number of trip points
+ * @trips: an array of trip points (0..ntrips - 1)
+ * @num_tbps: number of thermal bind params
+ * @tbps: an array of thermal bind params (0..num_tbps - 1)
+ * @sensor_data: sensor private data used while reading temperature and trend
+ * @get_temp: sensor callback to read temperature
+ * @get_trend: sensor callback to read temperature trend
+ */
+
+struct __thermal_zone {
+ enum thermal_device_mode mode;
+ int passive_delay;
+ int polling_delay;
+
+ /* trip data */
+ int ntrips;
+ struct __thermal_trip *trips;
+
+ /* cooling binding data */
+ int num_tbps;
+ struct __thermal_bind_params *tbps;
+
+ /* sensor interface */
+ void *sensor_data;
+ int (*get_temp)(void *, long *);
+ int (*get_trend)(void *, long *);
+};
+
+/*** DT thermal zone device callbacks ***/
+
+static int of_thermal_get_temp(struct thermal_zone_device *tz,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (!data->get_temp)
+ return -EINVAL;
+
+ return data->get_temp(data->sensor_data, temp);
+}
+
+static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
+ enum thermal_trend *trend)
+{
+ struct __thermal_zone *data = tz->devdata;
+ long dev_trend;
+ int r;
+
+ if (!data->get_trend)
+ return -EINVAL;
+
+ r = data->get_trend(data->sensor_data, &dev_trend);
+ if (r)
+ return r;
+
+ /* TODO: These intervals might have some thresholds, but in core code */
+ if (dev_trend > 0)
+ *trend = THERMAL_TREND_RAISING;
+ else if (dev_trend < 0)
+ *trend = THERMAL_TREND_DROPPING;
+ else
+ *trend = THERMAL_TREND_STABLE;
+
+ return 0;
+}
+
+static int of_thermal_bind(struct thermal_zone_device *thermal,
+ struct thermal_cooling_device *cdev)
+{
+ struct __thermal_zone *data = thermal->devdata;
+ int i;
+
+ if (!data || IS_ERR(data))
+ return -ENODEV;
+
+ /* find where to bind */
+ for (i = 0; i < data->num_tbps; i++) {
+ struct __thermal_bind_params *tbp = data->tbps + i;
+
+ if (tbp->cooling_device == cdev->np) {
+ int ret;
+
+ ret = thermal_zone_bind_cooling_device(thermal,
+ tbp->trip_id, cdev,
+ tbp->min,
+ tbp->max);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int of_thermal_unbind(struct thermal_zone_device *thermal,
+ struct thermal_cooling_device *cdev)
+{
+ struct __thermal_zone *data = thermal->devdata;
+ int i;
+
+ if (!data || IS_ERR(data))
+ return -ENODEV;
+
+ /* find where to unbind */
+ for (i = 0; i < data->num_tbps; i++) {
+ struct __thermal_bind_params *tbp = data->tbps + i;
+
+ if (tbp->cooling_device == cdev->np) {
+ int ret;
+
+ ret = thermal_zone_unbind_cooling_device(thermal,
+ tbp->trip_id, cdev);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int of_thermal_get_mode(struct thermal_zone_device *tz,
+ enum thermal_device_mode *mode)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ *mode = data->mode;
+
+ return 0;
+}
+
+static int of_thermal_set_mode(struct thermal_zone_device *tz,
+ enum thermal_device_mode mode)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ mutex_lock(&tz->lock);
+
+ if (mode == THERMAL_DEVICE_ENABLED)
+ tz->polling_delay = data->polling_delay;
+ else
+ tz->polling_delay = 0;
+
+ mutex_unlock(&tz->lock);
+
+ data->mode = mode;
+ thermal_zone_device_update(tz);
+
+ return 0;
+}
+
+static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
+ enum thermal_trip_type *type)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *type = data->trips[trip].type;
+
+ return 0;
+}
+
+static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *temp = data->trips[trip].temperature;
+
+ return 0;
+}
+
+static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
+ unsigned long temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ /* thermal fw should take care of data->mask & (1 << trip) */
+ data->trips[trip].temperature = temp;
+
+ return 0;
+}
+
+static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
+ unsigned long *hyst)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *hyst = data->trips[trip].hysteresis;
+
+ return 0;
+}
+
+static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
+ unsigned long hyst)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ /* thermal fw should take care of data->mask & (1 << trip) */
+ data->trips[trip].hysteresis = hyst;
+
+ return 0;
+}
+
+static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+ int i;
+
+ for (i = 0; i < data->ntrips; i++)
+ if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
+ *temp = data->trips[i].temperature;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static struct thermal_zone_device_ops of_thermal_ops = {
+ .get_mode = of_thermal_get_mode,
+ .set_mode = of_thermal_set_mode,
+
+ .get_trip_type = of_thermal_get_trip_type,
+ .get_trip_temp = of_thermal_get_trip_temp,
+ .set_trip_temp = of_thermal_set_trip_temp,
+ .get_trip_hyst = of_thermal_get_trip_hyst,
+ .set_trip_hyst = of_thermal_set_trip_hyst,
+ .get_crit_temp = of_thermal_get_crit_temp,
+
+ .bind = of_thermal_bind,
+ .unbind = of_thermal_unbind,
+};
+
+/*** sensor API ***/
+
+static struct thermal_zone_device *
+thermal_zone_of_add_sensor(struct device_node *zone,
+ struct device_node *sensor, void *data,
+ int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ struct thermal_zone_device *tzd;
+ struct __thermal_zone *tz;
+
+ tzd = thermal_zone_get_zone_by_name(zone->name);
+ if (IS_ERR(tzd))
+ return ERR_PTR(-EPROBE_DEFER);
+
+ tz = tzd->devdata;
+
+ mutex_lock(&tzd->lock);
+ tz->get_temp = get_temp;
+ tz->get_trend = get_trend;
+ tz->sensor_data = data;
+
+ tzd->ops->get_temp = of_thermal_get_temp;
+ tzd->ops->get_trend = of_thermal_get_trend;
+ mutex_unlock(&tzd->lock);
+
+ return tzd;
+}
+
+/**
+ * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
+ * @dev: a valid struct device pointer of a sensor device. Must contain
+ * a valid .of_node, for the sensor node.
+ * @sensor_id: a sensor identifier, in case the sensor IP has more
+ * than one sensors
+ * @data: a private pointer (owned by the caller) that will be passed
+ * back, when a temperature reading is needed.
+ * @get_temp: a pointer to a function that reads the sensor temperature.
+ * @get_trend: a pointer to a function that reads the sensor temperature trend.
+ *
+ * This function will search the list of thermal zones described in device
+ * tree and look for the zone that refer to the sensor device pointed by
+ * @dev->of_node as temperature providers. For the zone pointing to the
+ * sensor node, the sensor will be added to the DT thermal zone device.
+ *
+ * The thermal zone temperature is provided by the @get_temp function
+ * pointer. When called, it will have the private pointer @data back.
+ *
+ * The thermal zone temperature trend is provided by the @get_trend function
+ * pointer. When called, it will have the private pointer @data back.
+ *
+ * TODO:
+ * 01 - This function must enqueue the new sensor instead of using
+ * it as the only source of temperature values.
+ *
+ * 02 - There must be a way to match the sensor with all thermal zones
+ * that refer to it.
+ *
+ * Return: On success returns a valid struct thermal_zone_device,
+ * otherwise, it returns a corresponding ERR_PTR(). Caller must
+ * check the return value with help of IS_ERR() helper.
+ */
+struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ struct device_node *np, *child, *sensor_np;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np)
+ return ERR_PTR(-ENODEV);
+
+ if (!dev || !dev->of_node)
+ return ERR_PTR(-EINVAL);
+
+ sensor_np = dev->of_node;
+
+ for_each_child_of_node(np, child) {
+ struct of_phandle_args sensor_specs;
+ int ret, id;
+
+ /* For now, thermal framework supports only 1 sensor per zone */
+ ret = of_parse_phandle_with_args(child, "thermal-sensors",
+ "#thermal-sensor-cells",
+ 0, &sensor_specs);
+ if (ret)
+ continue;
+
+ if (sensor_specs.args_count < 1)
+ id = 0;
+ else
+ id = sensor_specs.args[0];
+
+ if (sensor_specs.np == sensor_np && id == sensor_id) {
+ of_node_put(np);
+ return thermal_zone_of_add_sensor(child, sensor_np,
+ data,
+ get_temp,
+ get_trend);
+ }
+ }
+ of_node_put(np);
+
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
+
+/**
+ * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
+ * @dev: a valid struct device pointer of a sensor device. Must contain
+ * a valid .of_node, for the sensor node.
+ * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
+ *
+ * This function removes the sensor callbacks and private data from the
+ * thermal zone device registered with thermal_zone_of_sensor_register()
+ * API. It will also silent the zone by remove the .get_temp() and .get_trend()
+ * thermal zone device callbacks.
+ *
+ * TODO: When the support to several sensors per zone is added, this
+ * function must search the sensor list based on @dev parameter.
+ *
+ */
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tzd)
+{
+ struct __thermal_zone *tz;
+
+ if (!dev || !tzd || !tzd->devdata)
+ return;
+
+ tz = tzd->devdata;
+
+ /* no __thermal_zone, nothing to be done */
+ if (!tz)
+ return;
+
+ mutex_lock(&tzd->lock);
+ tzd->ops->get_temp = NULL;
+ tzd->ops->get_trend = NULL;
+
+ tz->get_temp = NULL;
+ tz->get_trend = NULL;
+ tz->sensor_data = NULL;
+ mutex_unlock(&tzd->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
+
+/*** functions parsing device tree nodes ***/
+
+/**
+ * thermal_of_populate_bind_params - parse and fill cooling map data
+ * @np: DT node containing a cooling-map node
+ * @__tbp: data structure to be filled with cooling map info
+ * @trips: array of thermal zone trip points
+ * @ntrips: number of trip points inside trips.
+ *
+ * This function parses a cooling-map type of node represented by
+ * @np parameter and fills the read data into @__tbp data structure.
+ * It needs the already parsed array of trip points of the thermal zone
+ * in consideration.
+ *
+ * Return: 0 on success, proper error code otherwise
+ */
+static int thermal_of_populate_bind_params(struct device_node *np,
+ struct __thermal_bind_params *__tbp,
+ struct __thermal_trip *trips,
+ int ntrips)
+{
+ struct of_phandle_args cooling_spec;
+ struct device_node *trip;
+ int ret, i;
+ u32 prop;
+
+ /* Default weight. Usage is optional */
+ __tbp->usage = 0;
+ ret = of_property_read_u32(np, "contribution", &prop);
+ if (ret == 0)
+ __tbp->usage = prop;
+
+ trip = of_parse_phandle(np, "trip", 0);
+ if (!trip) {
+ pr_err("missing trip property\n");
+ return -ENODEV;
+ }
+
+ /* match using device_node */
+ for (i = 0; i < ntrips; i++)
+ if (trip == trips[i].np) {
+ __tbp->trip_id = i;
+ break;
+ }
+
+ if (i == ntrips) {
+ ret = -ENODEV;
+ goto end;
+ }
+
+ ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
+ 0, &cooling_spec);
+ if (ret < 0) {
+ pr_err("missing cooling_device property\n");
+ goto end;
+ }
+ __tbp->cooling_device = cooling_spec.np;
+ if (cooling_spec.args_count >= 2) { /* at least min and max */
+ __tbp->min = cooling_spec.args[0];
+ __tbp->max = cooling_spec.args[1];
+ } else {
+ pr_err("wrong reference to cooling device, missing limits\n");
+ }
+
+end:
+ of_node_put(trip);
+
+ return ret;
+}
+
+/**
+ * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
+ * into the device tree binding of 'trip', property type.
+ */
+static const char * const trip_types[] = {
+ [THERMAL_TRIP_ACTIVE] = "active",
+ [THERMAL_TRIP_PASSIVE] = "passive",
+ [THERMAL_TRIP_HOT] = "hot",
+ [THERMAL_TRIP_CRITICAL] = "critical",
+};
+
+/**
+ * thermal_of_get_trip_type - Get phy mode for given device_node
+ * @np: Pointer to the given device_node
+ * @type: Pointer to resulting trip type
+ *
+ * The function gets trip type string from property 'type',
+ * and store its index in trip_types table in @type,
+ *
+ * Return: 0 on success, or errno in error case.
+ */
+static int thermal_of_get_trip_type(struct device_node *np,
+ enum thermal_trip_type *type)
+{
+ const char *t;
+ int err, i;
+
+ err = of_property_read_string(np, "type", &t);
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < ARRAY_SIZE(trip_types); i++)
+ if (!strcasecmp(t, trip_types[i])) {
+ *type = i;
+ return 0;
+ }
+
+ return -ENODEV;
+}
+
+/**
+ * thermal_of_populate_trip - parse and fill one trip point data
+ * @np: DT node containing a trip point node
+ * @trip: trip point data structure to be filled up
+ *
+ * This function parses a trip point type of node represented by
+ * @np parameter and fills the read data into @trip data structure.
+ *
+ * Return: 0 on success, proper error code otherwise
+ */
+static int thermal_of_populate_trip(struct device_node *np,
+ struct __thermal_trip *trip)
+{
+ int prop;
+ int ret;
+
+ ret = of_property_read_u32(np, "temperature", &prop);
+ if (ret < 0) {
+ pr_err("missing temperature property\n");
+ return ret;
+ }
+ trip->temperature = prop;
+
+ ret = of_property_read_u32(np, "hysteresis", &prop);
+ if (ret < 0) {
+ pr_err("missing hysteresis property\n");
+ return ret;
+ }
+ trip->hysteresis = prop;
+
+ ret = thermal_of_get_trip_type(np, &trip->type);
+ if (ret < 0) {
+ pr_err("wrong trip type property\n");
+ return ret;
+ }
+
+ /* Required for cooling map matching */
+ trip->np = np;
+
+ return 0;
+}
+
+/**
+ * thermal_of_build_thermal_zone - parse and fill one thermal zone data
+ * @np: DT node containing a thermal zone node
+ *
+ * This function parses a thermal zone type of node represented by
+ * @np parameter and fills the read data into a __thermal_zone data structure
+ * and return this pointer.
+ *
+ * TODO: Missing properties to parse: thermal-sensor-names and coefficients
+ *
+ * Return: On success returns a valid struct __thermal_zone,
+ * otherwise, it returns a corresponding ERR_PTR(). Caller must
+ * check the return value with help of IS_ERR() helper.
+ */
+static struct __thermal_zone *
+thermal_of_build_thermal_zone(struct device_node *np)
+{
+ struct device_node *child = NULL, *gchild;
+ struct __thermal_zone *tz;
+ int ret, i;
+ u32 prop;
+
+ if (!np) {
+ pr_err("no thermal zone np\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ tz = kzalloc(sizeof(*tz), GFP_KERNEL);
+ if (!tz)
+ return ERR_PTR(-ENOMEM);
+
+ ret = of_property_read_u32(np, "polling-delay-passive", &prop);
+ if (ret < 0) {
+ pr_err("missing polling-delay-passive property\n");
+ goto free_tz;
+ }
+ tz->passive_delay = prop;
+
+ ret = of_property_read_u32(np, "polling-delay", &prop);
+ if (ret < 0) {
+ pr_err("missing polling-delay property\n");
+ goto free_tz;
+ }
+ tz->polling_delay = prop;
+
+ /* trips */
+ child = of_get_child_by_name(np, "trips");
+
+ /* No trips provided */
+ if (!child)
+ goto finish;
+
+ tz->ntrips = of_get_child_count(child);
+ if (tz->ntrips == 0) /* must have at least one child */
+ goto finish;
+
+ tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
+ if (!tz->trips) {
+ ret = -ENOMEM;
+ goto free_tz;
+ }
+
+ i = 0;
+ for_each_child_of_node(child, gchild) {
+ ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
+ if (ret)
+ goto free_trips;
+ }
+
+ of_node_put(child);
+
+ /* cooling-maps */
+ child = of_get_child_by_name(np, "cooling-maps");
+
+ /* cooling-maps not provided */
+ if (!child)
+ goto finish;
+
+ tz->num_tbps = of_get_child_count(child);
+ if (tz->num_tbps == 0)
+ goto finish;
+
+ tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
+ if (!tz->tbps) {
+ ret = -ENOMEM;
+ goto free_trips;
+ }
+
+ i = 0;
+ for_each_child_of_node(child, gchild)
+ ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
+ tz->trips, tz->ntrips);
+ if (ret)
+ goto free_tbps;
+
+finish:
+ of_node_put(child);
+ tz->mode = THERMAL_DEVICE_DISABLED;
+
+ return tz;
+
+free_tbps:
+ kfree(tz->tbps);
+free_trips:
+ kfree(tz->trips);
+free_tz:
+ kfree(tz);
+ of_node_put(child);
+
+ return ERR_PTR(ret);
+}
+
+static inline void of_thermal_free_zone(struct __thermal_zone *tz)
+{
+ kfree(tz->tbps);
+ kfree(tz->trips);
+ kfree(tz);
+}
+
+/**
+ * of_parse_thermal_zones - parse device tree thermal data
+ *
+ * Initialization function that can be called by machine initialization
+ * code to parse thermal data and populate the thermal framework
+ * with hardware thermal zones info. This function only parses thermal zones.
+ * Cooling devices and sensor devices nodes are supposed to be parsed
+ * by their respective drivers.
+ *
+ * Return: 0 on success, proper error code otherwise
+ *
+ */
+int __init of_parse_thermal_zones(void)
+{
+ struct device_node *np, *child;
+ struct __thermal_zone *tz;
+ struct thermal_zone_device_ops *ops;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np) {
+ pr_debug("unable to find thermal zones\n");
+ return 0; /* Run successfully on systems without thermal DT */
+ }
+
+ for_each_child_of_node(np, child) {
+ struct thermal_zone_device *zone;
+ struct thermal_zone_params *tzp;
+
+ tz = thermal_of_build_thermal_zone(child);
+ if (IS_ERR(tz)) {
+ pr_err("failed to build thermal zone %s: %ld\n",
+ child->name,
+ PTR_ERR(tz));
+ continue;
+ }
+
+ ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
+ if (!ops)
+ goto exit_free;
+
+ tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
+ if (!tzp) {
+ kfree(ops);
+ goto exit_free;
+ }
+
+ /* No hwmon because there might be hwmon drivers registering */
+ tzp->no_hwmon = true;
+
+ zone = thermal_zone_device_register(child->name, tz->ntrips,
+ 0, tz,
+ ops, tzp,
+ tz->passive_delay,
+ tz->polling_delay);
+ if (IS_ERR(zone)) {
+ pr_err("Failed to build %s zone %ld\n", child->name,
+ PTR_ERR(zone));
+ kfree(tzp);
+ kfree(ops);
+ of_thermal_free_zone(tz);
+ /* attempting to build remaining zones still */
+ }
+ }
+
+ return 0;
+
+exit_free:
+ of_thermal_free_zone(tz);
+
+ /* no memory available, so free what we have built */
+ of_thermal_destroy_zones();
+
+ return -ENOMEM;
+}
+
+/**
+ * of_thermal_destroy_zones - remove all zones parsed and allocated resources
+ *
+ * Finds all zones parsed and added to the thermal framework and remove them
+ * from the system, together with their resources.
+ *
+ */
+void __exit of_thermal_destroy_zones(void)
+{
+ struct device_node *np, *child;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np) {
+ pr_err("unable to find thermal zones\n");
+ return;
+ }
+
+ for_each_child_of_node(np, child) {
+ struct thermal_zone_device *zone;
+
+ zone = thermal_zone_get_zone_by_name(child->name);
+ if (IS_ERR(zone))
+ continue;
+
+ thermal_zone_device_unregister(zone);
+ kfree(zone->tzp);
+ kfree(zone->ops);
+ of_thermal_free_zone(zone->devdata);
+ }
+}
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index f7a9f4f..fec3351 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1371,7 +1371,7 @@ static void remove_trip_attrs(struct thermal_zone_device *tz)
*/
struct thermal_zone_device *thermal_zone_device_register(const char *type,
int trips, int mask, void *devdata,
- const struct thermal_zone_device_ops *ops,
+ struct thermal_zone_device_ops *ops,
const struct thermal_zone_params *tzp,
int passive_delay, int polling_delay)
{
@@ -1751,8 +1751,14 @@ static int __init thermal_init(void)
if (result)
goto unregister_class;
+ result = of_parse_thermal_zones();
+ if (result)
+ goto exit_netlink;
+
return 0;
+exit_netlink:
+ genetlink_exit();
unregister_governors:
thermal_unregister_governors();
unregister_class:
@@ -1768,6 +1774,7 @@ error:
static void __exit thermal_exit(void)
{
+ of_thermal_destroy_zones();
genetlink_exit();
class_unregister(&thermal_class);
thermal_unregister_governors();
diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
index 7cf2f66..3db339f 100644
--- a/drivers/thermal/thermal_core.h
+++ b/drivers/thermal/thermal_core.h
@@ -77,4 +77,13 @@ static inline int thermal_gov_user_space_register(void) { return 0; }
static inline void thermal_gov_user_space_unregister(void) {}
#endif /* CONFIG_THERMAL_GOV_USER_SPACE */
+/* device tree support */
+#ifdef CONFIG_THERMAL_OF
+int of_parse_thermal_zones(void);
+void of_thermal_destroy_zones(void);
+#else
+static inline int of_parse_thermal_zones(void) { return 0; }
+static inline void of_thermal_destroy_zones(void) { }
+#endif
+
#endif /* __THERMAL_CORE_H__ */
diff --git a/include/dt-bindings/thermal/thermal.h b/include/dt-bindings/thermal/thermal.h
new file mode 100644
index 0000000..59c4581
--- /dev/null
+++ b/include/dt-bindings/thermal/thermal.h
@@ -0,0 +1,27 @@
+/*
+ * This header provides constants for most thermal bindings.
+ *
+ * Copyright (C) 2013 Texas Instruments
+ * Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * GPLv2 only
+ */
+
+#ifndef _DT_BINDINGS_THERMAL_THERMAL_H
+#define _DT_BINDINGS_THERMAL_THERMAL_H
+
+/*
+ * Here are the thermal trip types. This must
+ * match with enum thermal_trip_type at
+ * include/linux/thermal.h
+ */
+#define THERMAL_TRIP_ACTIVE "active"
+#define THERMAL_TRIP_PASSIVE "passive"
+#define THERMAL_TRIP_HOT "hot"
+#define THERMAL_TRIP_CRITICAL "critical"
+
+/* On cooling devices upper and lower limits */
+#define THERMAL_NO_LIMIT (-1UL)
+
+#endif
+
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index b268d3c..b780c5b 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -143,6 +143,7 @@ struct thermal_cooling_device {
int id;
char type[THERMAL_NAME_LENGTH];
struct device device;
+ struct device_node *np;
void *devdata;
const struct thermal_cooling_device_ops *ops;
bool updated; /* true if the cooling device does not need update */
@@ -172,7 +173,7 @@ struct thermal_zone_device {
int emul_temperature;
int passive;
unsigned int forced_passive;
- const struct thermal_zone_device_ops *ops;
+ struct thermal_zone_device_ops *ops;
const struct thermal_zone_params *tzp;
struct thermal_governor *governor;
struct list_head thermal_instances;
@@ -242,8 +243,31 @@ struct thermal_genl_event {
};
/* Function declarations */
+#ifdef CONFIG_THERMAL_OF
+struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *));
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tz);
+#else
+static inline struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ return NULL;
+}
+
+static inline
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tz)
+{
+}
+
+#endif
struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
- void *, const struct thermal_zone_device_ops *,
+ void *, struct thermal_zone_device_ops *,
const struct thermal_zone_params *, int, int);
void thermal_zone_device_unregister(struct thermal_zone_device *);
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* Re: [PATCHv7 03/18] thermal: introduce device tree parser
2013-09-27 3:13 ` [PATCHv7 03/18] thermal: introduce device tree parser Eduardo Valentin
@ 2013-09-30 15:36 ` Mark Rutland
[not found] ` <20130930153614.GA22259-NuALmloUBlrZROr8t4l/smS4ubULX0JqMm0uRHvK7Nw@public.gmane.org>
[not found] ` <1380251605-3804-4-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
1 sibling, 1 reply; 31+ messages in thread
From: Mark Rutland @ 2013-09-30 15:36 UTC (permalink / raw)
To: Eduardo Valentin
Cc: swarren@wwwdotorg.org, Pawel Moll, ian.campbell@citrix.com,
rob.herring@calxeda.com, linux@roeck-us.net, rui.zhang@intel.com,
wni@nvidia.com, grant.likely@linaro.org, durgadoss.r@intel.com,
linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
lm-sensors@lm-sensors.org, linux-kernel@vger.kernel.org
Hi Eduardo,
On Fri, Sep 27, 2013 at 04:13:10AM +0100, Eduardo Valentin wrote:
> This patch introduces a device tree bindings for
> describing the hardware thermal behavior and limits.
> Also a parser to read and interpret the data and feed
> it in the thermal framework is presented.
>
> This patch introduces a thermal data parser for device
> tree. The parsed data is used to build thermal zones
> and thermal binding parameters. The output data
> can then be used to deploy thermal policies.
>
> This patch adds also documentation regarding this
> API and how to define tree nodes to use
> this infrastructure.
>
> Note that, in order to be able to have control
> on the sensor registration on the DT thermal zone,
> it was required to allow changing the thermal zone
> .get_temp callback. For this reason, this patch
> also removes the 'const' modifier from the .ops
> field of thermal zone devices.
>
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
> ---
>
> Hello folks,
>
> For those interested on this work, here is a short changelog from v6:
> - Reviewed binding documentation and added type and size on all properties
> - Described 'thermal-zones' node in binding documentation
> - Using now cooling state terminology instead of cooling level
> - Renamed milliCelsius to millicelsius
> - Renamed cooling-attachments to 'cooling-maps'
> - Renamed sensor to thermal sensor
> - Renamed #sensor-cells to #thermal-sensor-cells
> - #thermal-sensor-cells now is allowed to be 0
> - Renamed 'sensors' property to 'thermal-sensors'
> - Changed trip type property to be now string and documented possible values
> - Described better the cooling properties
> - Now parses 'contribution' instead of 'usage'
> - Renamed cdev to cooling device
> - Renamed 'passive-delay' property to 'polling-delay-passive'
> - Fixed a couple of error messages to match the property name
> - Fixed a binding issue while using cpufreq as module
> - Reworked thermal_of_build_thermal_zone function so that it frees
> requested memory if something goes wrong and checks for sub-nodes
> with zero children.
>
> ---
> .../devicetree/bindings/thermal/thermal.txt | 537 +++++++++++++
> drivers/thermal/Kconfig | 13 +
> drivers/thermal/Makefile | 1 +
> drivers/thermal/of-thermal.c | 845 +++++++++++++++++++++
> drivers/thermal/thermal_core.c | 9 +-
> drivers/thermal/thermal_core.h | 9 +
> include/dt-bindings/thermal/thermal.h | 27 +
> include/linux/thermal.h | 28 +-
> 8 files changed, 1466 insertions(+), 3 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
> create mode 100644 drivers/thermal/of-thermal.c
> create mode 100644 include/dt-bindings/thermal/thermal.h
>
> diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
> new file mode 100644
> index 0000000..3dbc017
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/thermal.txt
> @@ -0,0 +1,537 @@
> +* Thermal Framework Device Tree descriptor
> +
> +Generic binding to provide a way of defining hardware thermal
> +structure using device tree. A thermal structure includes thermal
> +zones and their components, such as trip points, polling intervals,
> +sensors and cooling devices binding descriptors.
> +
> +The target of device tree thermal descriptors is to describe only
> +the hardware thermal aspects, not how the system must control or which
> +algorithm or policy must be taken in place.
> +
> +There are five types of nodes involved to describe thermal bindings:
> +- sensors: used to describe the device source of temperature sensing;
> +- cooling devices: used to describe devices source of power dissipation control;
> +- trip points: used to describe points in temperature domain defined to
> +make the system aware of hardware limits;
> +- cooling maps: used to describe links between trip points and
> +cooling devices;
> +- thermal zones: used to describe thermal data within the hardware;
> +
> +It follows a description of each type of these device tree nodes.
> +
> +Note: This binding is a working in progress.
What does this mean? Is the binding expected to change in incompatible
ways?
I see we have similar wording at the top of the clock bindings, which
should probably go -- it's ABI now...
> +
> +* Thermal sensor devices
> +
> +Thermal sensor devices are nodes providing temperature sensing capabilities on
> +thermal zones. Typical devices are I2C ADC converters and bandgaps. Theses are
> +nodes providing temperature data to thermal zones. Thermal sensor devices may
> +control one or more internal sensors.
> +
> +Required property:
> +- #thermal-sensor-cells: Used to provide sensor device specific information
> + Type: unsigned while referring to it. Typically 0, on thermal sensor
> + Size: one cell nodes with only one sensor, and at least 1 on nodes
> + with several internal sensors, in order
> + to identify uniquely the sensor instances within
> + the IC. See thermal zone binding for more details
> + on how consumers refer to sensor devices.
> +
> +* Cooling device nodes
> +
> +Cooling devices are nodes providing control on power dissipation. There
> +are essentially two ways to provide control on power dissipation. First
> +is by means of regulating device performance, which is known as passive
> +cooling. A typical passive cooling is a CPU that has dynamic voltage and
> +frequency scaling, and uses lower frequencies as cooling states.
> +Second is by means of activating devices in order to remove
> +the dissipated heat, which is known as active cooling, e.g. regulating
> +fan speeds. In both cases, cooling devices shall have a way to determine
> +the state of cooling in which the device is.
> +
> +Required property:
> +- cooling-min-state: An integer indicating the smallest
> + Type: unsigned cooling state accepted. Typically 0.
> + Size: one cell
> +
> +- cooling-max-state: An integer indicating the largest
> + Type: unsigned cooling state accepted.
> + Size: one cell
> +
> +- #cooling-cells: Used to provide cooling device specific information
> + Type: unsigned while referring to it. Must be at least 2, in order
> + Size: one cell to specify minimum and maximum cooling state used
> + in the reference. The first cell is the minimum
> + cooling state requested and the second cell is
> + the maximum cooling state requested in the reference.
> + See Cooling device maps section below for more details
> + on how consumers refer to cooling devices.
> +
> +* Trip points
> +
> +The trip node is a node to describe a point in the temperature domain
> +in which the system takes an action. This node describes just the point,
> +not the action.
> +
> +Required properties:
> +- temperature: An integer indicating the trip temperature level,
> + Type: signed in millicelsius.
> + Size: one cell
> +
> +- hysteresis: a (low) hysteresis value on 'temperature'. This is a
> + Type: unsigned relative value, in millicelsius.
> + Size: one cell
> +
> +- type: a string containing the trip type. Supported values are:
Odd spacing above.
> + "active": A trip point to enable active cooling
> + "passive": A trip point to enable passive cooling
> + "hot": A trip point to notify emergency
> + "critical": Hardware not reliable.
> + Type: string
> +
> +There are also string constants defined at
> +include/dt-bindings/thermal/thermal.h.
> +
> +* Cooling device maps
> +
> +The cooling device maps node is a node to describe how cooling devices
> +get assigned to trip points of the zone. The cooling devices are expected
> +to be loaded in the target system.
> +
> +Required properties:
> +- cooling-device: A phandle of a cooling device with its specifier,
> + Type: phandle referring to which cooling device is used in this
More odd spacing. There's a fair amount later that would be nice to fix
up too.
> + binding. The required specifiers are: the minimum
> + cooling state and the maximum cooling level used
> + in this map.
There seems to be some confusion as to the word "specifier". Typically,
a specifier is all the cells after the phandle described by the #*-cells
property for the node pointed to. So here there is one
cooling-specifier, which describes the min and max values, and possibly
some other values.
> +- trip: A phandle of a trip point node within the same thermal
> + Type: phandle zone.
> +
> +Optional property:
> +- contribution: The cooling contribution to the thermal zone of the
> + Type: unsigned referred cooling device at the referred trip point.
> + Size: one cell The contribution is a ratio of the sum
> + of all cooling contributions within a thermal zone.
> +
> +Note: Using the THERMAL_NO_LIMIT (-1L) constant in the cooling-device phandle
> +limit specifier means:
> +(i) - minimum state allowed for minimum cooling level used in the reference.
> +(ii) - maximum state allowed for maximum cooling level used in the reference.
> +Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
How does that work with an unsigned value? Does the code check for
0xffffffff, or compare against -1?
> +
> +* Thermal zone nodes
> +
> +The thermal zone node is the node containing all the required info
> +for describing a thermal zone, including its cooling device bindings. The
> +thermal zone node must contain, apart from its own properties, one node containing
> +trip nodes and one node containing all the zone cooling maps.
> +
> +Required properties:
> +- polling-delay-passive: The maximum number of milliseconds to wait
> + Type: unsigned between polls when performing passive cooling.
> + Size: one cell
Is this when performing passive cooling, or any passive or above (i.e.
any cooling whatsoever)?
> +
> +- polling-delay: The maximum number of milliseconds to wait between polls
> + Type: unsigned when checking this thermal zone.
> + Size: one cell
> +
> +- thermal-sensors: A list of sensor phandles and sensor specifier
> + Type: list of phandles used while monitoring the thermal zone.
The type and the description don't agree here. The type description can
probably be omitted as the description describes the format of the
property.
> +
> +- trips: A sub-node which is a container of only trip point nodes
> + Type: sub-node required to describe the thermal zone.
> +
> +- cooling-maps: A sub-node which is a container of only cooling device
> + Type: sub-node map nodes, used to describe the relation between trips
> + and cooling devices.
> +
> +Optional property:
> +- thermal-sensors-names: List of thermal sensor name strings sorted
> + Type: list of strings in the same order as the thermal-sensors
> + property.
Was there a reason for adding this?
There was some confusion over my request for cooling-specifier and
thermal-sensor-specifier terminology last time [1]. I was simply asking
for terminology, not -names properties.
> +
> +- coefficients: An array of integers (one signed cell) containing
> + Type: array coefficients to compose a linear relation between
> + Elem size: one cell the sensors described in the thermal-sensors property.
> + Elem type: signed Coefficients defaults to 1, in case this property
> + is not specified. A simple linear polynomial is used:
> + Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
> +
> + The coefficients are ordered and they match with sensors
> + by means of sensor ID. Additional coefficients are
> + interpreted as constant offsets.
> +
> +Note: The delay properties are bound to the maximum dT/dt (temperature
> +derivative over time) in two situations for a thermal zone:
> +(i) - when active cooling is activated (polling-delay-passive); and
Ah, so any coolnig implies the passive polling delay. That makes teh
naming confusing (active cooling means we're polling for the passive
delay). Sorry for the poor suggestion.
How about having polling-delay-cooled instead. That better describes
when it applies.
> +(ii) - when the zone just needs to be monitored (polling-delay).
> +The maximum dT/dt is highly bound to hardware power consumption and dissipation
> +capability.
It would be nice to have another line break here.
> +The delays are chosen to account for said max dT/dt, such that a device
s/are/should be/
> +does not cross several trip boundaries unexpectedly between polls. Choosing
> +the right polling delays shall avoid having the device in temperature ranges
> +that may damage the silicon structures and reduce silicon lifetime.
> +
> +* The thermal-zones node
> +
> +The "thermal-zones" node is a container for all thermal zone nodes. It shall
> +contain only sub-nodes describing thermal zones as in the section
> +"Thermal zone nodes".
I assume thermal-zones appears under /, rather than under a subnode? It
might be worth mentioning.
> +
> +* Examples
> +
> +Below are several examples on how to use thermal data descriptors
> +using device tree bindings:
> +
> +(a) - CPU thermal zone
> +
> +The CPU thermal zone example below describes how to setup one thermal zone
> +using one single sensor as temperature source and many cooling devices and
> +power dissipation control sources.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +cpus {
> + cpu0: cpu@0 {
> + ...
> + cooling-min-state = <0>;
> + cooling-max-state = <3>;
> + #cooling-cells = <2>; /* min followed by max */
> + };
> + ...
> +};
If we're going to give an example of cpu nodes with cooling-cells, we
should have a binding for cpu nodes explaining what the abstract cooling
properties mean for them.
What _specifically_ do each of the values 0,1,2,3 mean here? Are they
indexes of OPPs to use (which aren't shown in the example)? Are they
specific to a particular CPU (the compatible string for which is not
shown in the example)? Are they generic and applicable to all CPUs
somehow?
> +
> +&i2c1 {
> + ...
Having a comment inline describing this fictional sensor would be
useful, something like:
/*
* A simple fan controlller. Supports 10 speeds of operation
* (represented as 0-9).
*/
I didn't notice the block below until already having tried to comprehend
the example. Inline comments would help in that regard.
> + fan0: fan@0x48 {
> + ...
> + cooling-min-state = <0>;
> + cooling-max-state = <9>;
> + #cooling-cells = <2>; /* min followed by max */
> + };
> +};
> +
Similarly, it would be nice to have something here like:
/*
* A simple IC with a single bandgap temperature sensor.
*/
> +bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <0>;
> +};
> +
> +cpu-thermal: cpu-thermal {
This should be under a thermal-zones node. Similarly for the other
examples, they should have all relevant context.
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
The comment below is no longer relevant.
> + /* sensor ID */
> + thermal-sensors = <&bandgap0>;
> +
> + trips {
> + cpu-alert0: cpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_ACTIVE;
This got changed to a string in the binding, but is a CPP value here.
Similarly in many other places below.
> + };
> + cpu-alert1: cpu-alert {
> + temperature = <100000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_PASSIVE;
> + };
> + cpu-crit: cpu-crit {
> + temperature = <125000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_CRITICAL;
> + };
> + };
> +
> + cooling-maps {
> + map0 {
> + trip = <&cpu-alert0>;
> + cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
> + };
> + map1 {
> + trip = <&cpu-alert1>;
> + cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
> + };
> + map2 {
> + trip = <&cpu-alert1>;
> + cooling-device =
> + <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
> + };
> + };
> +};
> +
> +In the example above, the ADC sensor at address 0x0000ED00 is used to monitor
> +the zone 'cpu-thermal' using its the sensor 0. The fan0, a fan device controlled
> +via I2C bus 1, at adress 0x48, which has ten different cooling states.
This is a little difficult to understand. How about:
In the example above, the ADC sensor (bandgap0) at address 0x0000ED00 is
used to monitor the zone 'cpu-thermal' using its sole sensor. A fan
device (fan0) is controlled via I2C bus 1, at address 0x48, and has ten
different cooling states 0-9.
> +It is used to remove the heat out of the thermal zone 'cpu-thermal' using its
> +cooling states from its minimum to 4, when it reaches trip point 'cpu-alert0'
> +at 90C, as an example of active cooling. The same cooling device is used at
> +'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
> +linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
> +using all its cooling states at trip point 'cpu-alert1',
> +which is a trip point at 100C.
> +
> +(b) - IC with several internal sensors
> +
> +The example below describes how to deploy several thermal zones based off a
> +single sensor IC, assuming it has several internal sensors. This is a common
> +case on SoC designs with several internal IPs that may need different thermal
> +requirements, and thus may have their own sensor to monitor or detect internal
> +hotspots in their silicon.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <1>;
> +};
> +
> +cpu-thermal: cpu-thermal {
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 0>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + cpu-alert: cpu-alert {
> + temperature = <100000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_PASSIVE;
> + };
> + cpu-crit: cpu-crit {
> + temperature = <125000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_CRITICAL;
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> +};
> +
> +gpu-thermal: gpu-thermal {
> + polling-delay-passive = <120>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 1>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + gpu-alert: gpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_PASSIVE;
> + };
> + gpu-crit: gpu-crit {
> + temperature = <105000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_CRITICAL;
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> +};
> +
> +dsp-thermal: dsp-thermal {
> + polling-delay-passive = <50>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 2>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + dsp-alert: gpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_PASSIVE;
> + };
> + dsp-crit: gpu-crit {
> + temperature = <135000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = THERMAL_TRIP_CRITICAL;
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> +};
> +
> +In the example above there is one bandgap IC which has the capability to
> +monitor three sensors. The hardware has been designed so that sensors are
> +placed on different places in the DIE to monitor different temperature
> +hotspots: one for CPU thermal zone, one for GPU thermal zone and the
> +other to monitor a DSP thermal zone.
> +
> +Thus, there is a need to assign each sensor provided by the bandgap IC
> +to different thermal zones. This is achieved by means of using the
> +#thermal-sensor-cells property and using the first specifier as sensor ID.
> +In the example, then, bandgap.sensor0 is used to monitor CPU thermal zone,
The reference to bandgap.sensor0 is confusing. How about saying
<&bandgap 0> instead? It makes it far easier to see correspondence
between the text and the dt. Similarly for the other instances below.
> +bandgap.sensor1 is used to monitor GPU thermal zone and bandgap.sensor2
> +is used to monitor DSP thermal zone. Each zone may be uncorrelated,
> +having its own dT/dt requirements, trips and cooling maps.
> +
> +
> +(c) - Several sensors within one single thermal zone
> +
> +The example below illustrates how to use more than one sensor within
> +one thermal zone.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +&i2c1 {
> + ...
> + adc: sensor@0x49 {
> + ...
> + #thermal-sensor-cells = <0>;
> + };
> +};
> +
> +bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <0>;
> +};
> +
> +cpu-thermal: cpu-thermal {
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0>,
> + <&adc>;
> + thermal-sensors-names = "cpu", "pcb north";
> +
> + /* hotspot = 100 * bandgap - 120 * adc + 484 */
> + coefficients = <100 -120 484>;
> +
> + trips {
> + ...
> + };
> +
> + cooling-maps {
> + ...
> + };
> +};
> +
> +In some cases, there is a need to use more than one sensor to extrapolate
> +a thermal hotspot in the silicon. The above example illustrate this situation.
s/illustrate/illustrates/
> +For instance, it may be the case that a sensor external to CPU IP may be place
s/place/placed/
> +close to CPU hotspot and together with internal CPU sensor, it is used
> +to determine the hotspot. The hyppotetical extrapolation rule would be:
s/hyppotetical/hypothetical/
[...]
> +static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
> + unsigned long temp)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + /* thermal fw should take care of data->mask & (1 << trip) */
I mentioned this last time, and it's tripped me up again while reading:
It's rather too easy to read "fw" as "firmware" and get confused.
s/fw/framework/ please. :)
> + data->trips[trip].temperature = temp;
> +
> + return 0;
> +}
[...]
> +struct thermal_zone_device *
> +thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
> + void *data, int (*get_temp)(void *, long *),
> + int (*get_trend)(void *, long *))
> +{
> + struct device_node *np, *child, *sensor_np;
> +
> + np = of_find_node_by_name(NULL, "thermal-zones");
> + if (!np)
> + return ERR_PTR(-ENODEV);
> +
> + if (!dev || !dev->of_node)
> + return ERR_PTR(-EINVAL);
> +
> + sensor_np = dev->of_node;
> +
> + for_each_child_of_node(np, child) {
> + struct of_phandle_args sensor_specs;
> + int ret, id;
> +
> + /* For now, thermal framework supports only 1 sensor per zone */
> + ret = of_parse_phandle_with_args(child, "thermal-sensors",
> + "#thermal-sensor-cells",
> + 0, &sensor_specs);
> + if (ret)
> + continue;
> +
> + if (sensor_specs.args_count < 1)
> + id = 0;
> + else
> + id = sensor_specs.args[0];
> +
For the moment it might be worth printing a warning if args_count > 1,
as thermal management might not function correctly.
> + if (sensor_specs.np == sensor_np && id == sensor_id) {
> + of_node_put(np);
> + return thermal_zone_of_add_sensor(child, sensor_np,
> + data,
> + get_temp,
> + get_trend);
> + }
> + }
> + of_node_put(np);
> +
> + return ERR_PTR(-ENODEV);
> +}
> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
Cheers,
Mark.
[1] https://lkml.org/lkml/2013/9/24/501
^ permalink raw reply [flat|nested] 31+ messages in thread[parent not found: <1380251605-3804-4-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>]
* [PATCHv8 03/18] thermal: introduce device tree parser
[not found] ` <1380251605-3804-4-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
@ 2013-10-01 2:39 ` Eduardo Valentin
2013-10-07 20:51 ` Mark Rutland
0 siblings, 1 reply; 31+ messages in thread
From: Eduardo Valentin @ 2013-10-01 2:39 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin
This patch introduces a device tree bindings for
describing the hardware thermal behavior and limits.
Also a parser to read and interpret the data and feed
it in the thermal framework is presented.
This patch introduces a thermal data parser for device
tree. The parsed data is used to build thermal zones
and thermal binding parameters. The output data
can then be used to deploy thermal policies.
This patch adds also documentation regarding this
API and how to define tree nodes to use
this infrastructure.
Note that, in order to be able to have control
on the sensor registration on the DT thermal zone,
it was required to allow changing the thermal zone
.get_temp callback. For this reason, this patch
also removes the 'const' modifier from the .ops
field of thermal zone devices.
Cc: Zhang Rui <rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
Hello Mark, folks,
So, here is v8. Pretty small changes. Most are better
English phrasing in the binding document. It follows changelog:
- Several rephrasing in the binding document, including
spelling, grammar and better phrasing.
- Removed WiP warning from binding document.
- Several spacing and formatting changes in the binding document
- Used the '-specifier' nomenclature properly in the binding doc
- Removed the optional property 'thermal-sensors-names', because
it does not provide useful runtime information
- Fixed description of 'polling-delay-passive'
- Improved examples by adding comments and better explanation
- s/fw/framework/g
- Added a WARN when sensors specifiers are greater and 1.
All best,
Eduardo
---
.../devicetree/bindings/thermal/thermal.txt | 587 ++++++++++++++
drivers/thermal/Kconfig | 13 +
drivers/thermal/Makefile | 1 +
drivers/thermal/of-thermal.c | 849 +++++++++++++++++++++
drivers/thermal/thermal_core.c | 9 +-
drivers/thermal/thermal_core.h | 9 +
include/dt-bindings/thermal/thermal.h | 27 +
include/linux/thermal.h | 28 +-
8 files changed, 1520 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
create mode 100644 drivers/thermal/of-thermal.c
create mode 100644 include/dt-bindings/thermal/thermal.h
diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
new file mode 100644
index 0000000..ad06a8d
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/thermal.txt
@@ -0,0 +1,587 @@
+* Thermal Framework Device Tree descriptor
+
+This file describes a generic binding to provide a way of
+defining hardware thermal structure using device tree.
+A thermal structure includes thermal zones and their components,
+such as trip points, polling intervals, sensors and cooling devices
+binding descriptors.
+
+The target of device tree thermal descriptors is to describe only
+the hardware thermal aspects. The thermal device tree bindings are
+not about how the system must control or which algorithm or policy
+must be taken in place.
+
+There are five types of nodes involved to describe thermal bindings:
+- sensors: used to describe the device source of temperature sensing;
+- cooling devices: used to describe devices source of power dissipation control;
+- trip points: used to describe points in temperature domain defined to
+make the system aware of hardware limits;
+- cooling maps: used to describe links between trip points and cooling devices;
+- thermal zones: used to describe thermal data within the hardware;
+
+It follows a description of each type of these device tree nodes.
+
+* Thermal sensor devices
+
+Thermal sensor devices are nodes providing temperature sensing capabilities on
+thermal zones. Typical devices are I2C ADC converters and bandgaps. These are
+nodes providing temperature data to thermal zones. Thermal sensor devices may
+control one or more internal sensors.
+
+Required property:
+- #thermal-sensor-cells: Used to provide sensor device specific information
+ Type: unsigned while referring to it. Typically 0 on thermal sensor
+ Size: one cell nodes with only one sensor, and at least 1 on nodes
+ with several internal sensors, in order
+ to identify uniquely the sensor instances within
+ the IC. See thermal zone binding for more details
+ on how consumers refer to sensor devices.
+
+* Cooling device nodes
+
+Cooling devices are nodes providing control on power dissipation. There
+are essentially two ways to provide control on power dissipation. First
+is by means of regulating device performance, which is known as passive
+cooling. A typical passive cooling is a CPU that has dynamic voltage and
+frequency scaling (DVFS), and uses lower frequencies as cooling states.
+Second is by means of activating devices in order to remove
+the dissipated heat, which is known as active cooling, e.g. regulating
+fan speeds. In both cases, cooling devices shall have a way to determine
+the state of cooling in which the device is.
+
+Required properties:
+- cooling-min-state: An integer indicating the smallest
+ Type: unsigned cooling state accepted. Typically 0.
+ Size: one cell
+
+- cooling-max-state: An integer indicating the largest
+ Type: unsigned cooling state accepted.
+ Size: one cell
+
+- #cooling-cells: Used to provide cooling device specific information
+ Type: unsigned while referring to it. Must be at least 2, in order
+ Size: one cell to specify minimum and maximum cooling state used
+ in the reference. The first cell is the minimum
+ cooling state requested and the second cell is
+ the maximum cooling state requested in the reference.
+ See Cooling device maps section below for more details
+ on how consumers refer to cooling devices.
+
+* Trip points
+
+The trip node is a node to describe a point in the temperature domain
+in which the system takes an action. This node describes just the point,
+not the action.
+
+Required properties:
+- temperature: An integer indicating the trip temperature level,
+ Type: signed in millicelsius.
+ Size: one cell
+
+- hysteresis: a (low) hysteresis value on 'temperature'. This is a
+ Type: unsigned relative value, in millicelsius.
+ Size: one cell
+
+- type: a string containing the trip type. Supported values are:
+ "active": A trip point to enable active cooling
+ "passive": A trip point to enable passive cooling
+ "hot": A trip point to notify emergency
+ "critical": Hardware not reliable.
+ Type: string
+
+There are also string constants defined at
+include/dt-bindings/thermal/thermal.h.
+
+* Cooling device maps
+
+The cooling device maps node is a node to describe how cooling devices
+get assigned to trip points of the zone. The cooling devices are expected
+to be loaded in the target system.
+
+Required properties:
+- cooling-device: A phandle of a cooling device with its specifier,
+ Type: phandle of referring to which cooling device is used in this
+ cooling device binding. In the cooling specifier, the first cell
+ is the minimum cooling state and the second cell
+ is the maximum cooling state used in this map.
+- trip: A phandle of a trip point node within the same thermal
+ Type: phandle of zone.
+ trip point node
+
+Optional property:
+- contribution: The cooling contribution to the thermal zone of the
+ Type: unsigned referred cooling device at the referred trip point.
+ Size: one cell The contribution is a ratio of the sum
+ of all cooling contributions within a thermal zone.
+
+Note: Using the THERMAL_NO_LIMIT (-1UL) constant in the cooling-device phandle
+limit specifier means:
+(i) - minimum state allowed for minimum cooling state used in the reference.
+(ii) - maximum state allowed for maximum cooling state used in the reference.
+Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
+
+* Thermal zone nodes
+
+The thermal zone node is the node containing all the required info
+for describing a thermal zone, including its cooling device bindings. The
+thermal zone node must contain, apart from its own properties, one sub-node
+containing trip nodes and one sub-node containing all the zone cooling maps.
+
+Required properties:
+- polling-delay: The maximum number of milliseconds to wait between polls
+ Type: unsigned when checking this thermal zone.
+ Size: one cell
+
+- polling-delay-passive: The maximum number of milliseconds to wait
+ Type: unsigned between polls when performing passive cooling.
+ Size: one cell
+
+- thermal-sensors: A list of thermal sensor phandles and sensor specifier
+ Type: list of used while monitoring the thermal zone.
+ sensor phandles
+
+- trips: A sub-node which is a container of only trip point nodes
+ Type: sub-node required to describe the thermal zone.
+
+- cooling-maps: A sub-node which is a container of only cooling device
+ Type: sub-node map nodes, used to describe the relation between trips
+ and cooling devices.
+
+Optional property:
+- coefficients: An array of integers (one signed cell) containing
+ Type: array coefficients to compose a linear relation between
+ Elem size: one cell the sensors listed in the thermal-sensors property.
+ Elem type: signed Coefficients defaults to 1, in case this property
+ is not specified. A simple linear polynomial is used:
+ Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
+
+ The coefficients are ordered and they match with sensors
+ by means of sensor ID. Additional coefficients are
+ interpreted as constant offset.
+
+Note: The delay properties are bound to the maximum dT/dt (temperature
+derivative over time) in two situations for a thermal zone:
+(i) - when passive cooling is activated (polling-delay-passive); and
+(ii) - when the zone just needs to be monitored (polling-delay) or
+when active cooling is activated.
+
+The maximum dT/dt is highly bound to hardware power consumption and dissipation
+capability. The delays should be chosen to account for said max dT/dt,
+such that a device does not cross several trip boundaries unexpectedly
+between polls. Choosing the right polling delays shall avoid having the
+device in temperature ranges that may damage the silicon structures and
+reduce silicon lifetime.
+
+* The thermal-zones node
+
+The "thermal-zones" node is a container for all thermal zone nodes. It shall
+contain only sub-nodes describing thermal zones as in the section
+"Thermal zone nodes". The "thermal-zones" node appears under "/".
+
+* Examples
+
+Below are several examples on how to use thermal data descriptors
+using device tree bindings:
+
+(a) - CPU thermal zone
+
+The CPU thermal zone example below describes how to setup one thermal zone
+using one single sensor as temperature source and many cooling devices and
+power dissipation control sources.
+
+#include <dt-bindings/thermal/thermal.h>
+
+cpus {
+ /*
+ * Here is an example of describing a cooling device for a DVFS
+ * capable CPU. The CPU node describes its four OPPs.
+ * The cooling states possible are 0..3, and they are
+ * used as OPP indexes. The minimum cooling state is 0, which means
+ * all four OPPs can be available to the system. The maximum
+ * cooling state is 3, which means only the lowest OPPs (198MHz@0.85V)
+ * can be available in the system.
+ */
+ cpu0: cpu@0 {
+ ...
+ operating-points = <
+ /* kHz uV */
+ 970000 1200000
+ 792000 1100000
+ 396000 950000
+ 198000 850000
+ >;
+ cooling-min-state = <0>;
+ cooling-max-state = <3>;
+ #cooling-cells = <2>; /* min followed by max */
+ };
+ ...
+};
+
+&i2c1 {
+ ...
+ /*
+ * A simple fan controller which supports 10 speeds of operation
+ * (represented as 0-9).
+ */
+ fan0: fan@0x48 {
+ ...
+ cooling-min-state = <0>;
+ cooling-max-state = <9>;
+ #cooling-cells = <2>; /* min followed by max */
+ };
+};
+
+ocp {
+ ...
+ /*
+ * A simple IC with a single bandgap temperature sensor.
+ */
+ bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <0>;
+ };
+};
+
+thermal-zones {
+ cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ thermal-sensors = <&bandgap0>;
+
+ trips {
+ cpu-alert0: cpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "active";
+ };
+ cpu-alert1: cpu-alert {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ cpu-crit: cpu-crit {
+ temperature = <125000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&cpu-alert0>;
+ cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
+ };
+ map1 {
+ trip = <&cpu-alert1>;
+ cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
+ };
+ map2 {
+ trip = <&cpu-alert1>;
+ cooling-device =
+ <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
+ };
+ };
+ };
+};
+
+In the example above, the ADC sensor (bandgap0) at address 0x0000ED00 is
+used to monitor the zone 'cpu-thermal' using its sole sensor. A fan
+device (fan0) is controlled via I2C bus 1, at address 0x48, and has ten
+different cooling states 0-9. It is used to remove the heat out of
+the thermal zone 'cpu-thermal' using its cooling states
+from its minimum to 4, when it reaches trip point 'cpu-alert0'
+at 90C, as an example of active cooling. The same cooling device is used at
+'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
+linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
+using all its cooling states at trip point 'cpu-alert1',
+which is a trip point at 100C. On the thermal zone 'cpu-thermal', at the
+temperature of 125C, represented by the trip point 'cpu-crit', the silicon
+is not reliable anymore.
+
+(b) - IC with several internal sensors
+
+The example below describes how to deploy several thermal zones based off a
+single sensor IC, assuming it has several internal sensors. This is a common
+case on SoC designs with several internal IPs that may need different thermal
+requirements, and thus may have their own sensor to monitor or detect internal
+hotspots in their silicon.
+
+#include <dt-bindings/thermal/thermal.h>
+
+ocp {
+ ...
+ /*
+ * A simple IC with several bandgap temperature sensors.
+ */
+ bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <1>;
+ };
+};
+
+thermal-zones {
+ cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 0>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ cpu-alert: cpu-alert {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ cpu-crit: cpu-crit {
+ temperature = <125000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+ };
+
+ gpu-thermal: gpu-thermal {
+ polling-delay-passive = <120>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 1>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ gpu-alert: gpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ gpu-crit: gpu-crit {
+ temperature = <105000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+ };
+
+ dsp-thermal: dsp-thermal {
+ polling-delay-passive = <50>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap0 2>;
+
+ trips {
+ /* each zone within the SoC may have its own trips */
+ dsp-alert: gpu-alert {
+ temperature = <90000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ dsp-crit: gpu-crit {
+ temperature = <135000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ /* each zone within the SoC may have its own cooling */
+ ...
+ };
+ };
+};
+
+In the example above, there is one bandgap IC which has the capability to
+monitor three sensors. The hardware has been designed so that sensors are
+placed on different places in the DIE to monitor different temperature
+hotspots: one for CPU thermal zone, one for GPU thermal zone and the
+other to monitor a DSP thermal zone.
+
+Thus, there is a need to assign each sensor provided by the bandgap IC
+to different thermal zones. This is achieved by means of using the
+#thermal-sensor-cells property and using the first cell of the sensor
+specifier as sensor ID. In the example, then, <bandgap 0> is used to
+monitor CPU thermal zone, <bandgap 1> is used to monitor GPU thermal
+zone and <bandgap 2> is used to monitor DSP thermal zone. Each zone
+may be uncorrelated, having its own dT/dt requirements, trips
+and cooling maps.
+
+
+(c) - Several sensors within one single thermal zone
+
+The example below illustrates how to use more than one sensor within
+one thermal zone.
+
+#include <dt-bindings/thermal/thermal.h>
+
+&i2c1 {
+ ...
+ /*
+ * A simple IC with a single temperature sensor.
+ */
+ adc: sensor@0x49 {
+ ...
+ #thermal-sensor-cells = <0>;
+ };
+};
+
+ocp {
+ ...
+ /*
+ * A simple IC with a single bandgap temperature sensor.
+ */
+ bandgap0: bandgap@0x0000ED00 {
+ ...
+ #thermal-sensor-cells = <0>;
+ };
+};
+
+thermal-zones {
+ cpu-thermal: cpu-thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ thermal-sensors = <&bandgap0>, /* cpu */
+ <&adc>; /* pcb north */
+
+ /* hotspot = 100 * bandgap - 120 * adc + 484 */
+ coefficients = <100 -120 484>;
+
+ trips {
+ ...
+ };
+
+ cooling-maps {
+ ...
+ };
+ };
+};
+
+In some cases, there is a need to use more than one sensor to extrapolate
+a thermal hotspot in the silicon. The above example illustrates this situation.
+For instance, it may be the case that a sensor external to CPU IP may be placed
+close to CPU hotspot and together with internal CPU sensor, it is used
+to determine the hotspot. Assuming this is the case for the above example,
+the hypothetical extrapolation rule would be:
+ hotspot = 100 * bandgap - 120 * adc + 484
+
+In other context, the same idea can be used to add fixed offset. For instance,
+consider the hotspot extrapolation rule below:
+ hotspot = 1 * adc + 6000
+
+In the above equation, the hotspot is always 6C higher than what is read
+from the ADC sensor. The binding would be then:
+ thermal-sensors = <&adc>;
+
+ /* hotspot = 1 * adc + 6000 */
+ coefficients = <1 6000>;
+
+(d) - Board thermal
+
+The board thermal example below illustrates how to setup one thermal zone
+with many sensors and many cooling devices.
+
+#include <dt-bindings/thermal/thermal.h>
+
+&i2c1 {
+ ...
+ /*
+ * An IC with several temperature sensor.
+ */
+ adc-dummy: sensor@0x50 {
+ ...
+ #thermal-sensor-cells = <1>; /* sensor internal ID */
+ };
+};
+
+thermal-zones {
+ batt-thermal {
+ polling-delay-passive = <500>; /* milliseconds */
+ polling-delay = <2500>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&adc-dummy 4>;
+
+ trips {
+ ...
+ };
+
+ cooling-maps {
+ ...
+ };
+ };
+
+ board-thermal: board-thermal {
+ polling-delay-passive = <1000>; /* milliseconds */
+ polling-delay = <2500>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&adc-dummy 0>, /* pcb top edge */
+ <&adc-dummy 1>, /* lcd */
+ <&adc-dymmy 2>; /* back cover */
+ /*
+ * An array of coefficients describing the sensor
+ * linear relation. E.g.:
+ * z = c1*x1 + c2*x2 + c3*x3
+ */
+ coefficients = <1200 -345 890>;
+
+ trips {
+ /* Trips are based on resulting linear equation */
+ cpu-trip: cpu-trip {
+ temperature = <60000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ gpu-trip: gpu-trip {
+ temperature = <55000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ }
+ lcd-trip: lcp-trip {
+ temperature = <53000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "passive";
+ };
+ crit-trip: crit-trip {
+ temperature = <68000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&cpu-trip>;
+ cooling-device = <&cpu0 0 2>;
+ contribution = <55>;
+ };
+ map1 {
+ trip = <&gpu-trip>;
+ cooling-device = <&gpu0 0 2>;
+ contribution = <20>;
+ };
+ map2 {
+ trip = <&lcd-trip>;
+ cooling-device = <&lcd0 5 10>;
+ contribution = <15>;
+ };
+ };
+ };
+};
+
+The above example is a mix of previous examples, a sensor IP with several internal
+sensors used to monitor different zones, one of them is composed by several sensors and
+with different cooling devices.
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index dbfc390..dd81eb8 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -29,6 +29,19 @@ config THERMAL_HWMON
Say 'Y' here if you want all thermal sensors to
have hwmon sysfs interface too.
+config THERMAL_OF
+ bool
+ prompt "APIs to parse thermal data out of device tree"
+ depends on OF
+ default y
+ help
+ This options provides helpers to add the support to
+ read and parse thermal data definitions out of the
+ device tree blob.
+
+ Say 'Y' here if you need to build thermal infrastructure
+ based on device tree.
+
choice
prompt "Default Thermal governor"
default THERMAL_DEFAULT_GOV_STEP_WISE
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 584b363..4b03956 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -7,6 +7,7 @@ thermal_sys-y += thermal_core.o
# interface to/from other layers providing sensors
thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
+thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
# governors
thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
new file mode 100644
index 0000000..66f9eb2
--- /dev/null
+++ b/drivers/thermal/of-thermal.c
@@ -0,0 +1,849 @@
+/*
+ * of-thermal.c - Generic Thermal Management device tree support.
+ *
+ * Copyright (C) 2013 Texas Instruments
+ * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
+ *
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#include <linux/thermal.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/string.h>
+
+#include "thermal_core.h"
+
+/*** Private data structures to represent thermal device tree data ***/
+
+/**
+ * struct __thermal_trip - representation of a point in temperature domain
+ * @np: pointer to struct device_node that this trip point was created from
+ * @temperature: temperature value in miliCelsius
+ * @hysteresis: relative hysteresis in miliCelsius
+ * @type: trip point type
+ */
+
+struct __thermal_trip {
+ struct device_node *np;
+ unsigned long int temperature;
+ unsigned long int hysteresis;
+ enum thermal_trip_type type;
+};
+
+/**
+ * struct __thermal_bind_param - a match between trip and cooling device
+ * @cooling_device: a pointer to identify the referred cooling device
+ * @trip_id: the trip point index
+ * @usage: the percentage (from 0 to 100) of cooling contribution
+ * @min: minimum cooling state used at this trip point
+ * @max: maximum cooling state used at this trip point
+ */
+
+struct __thermal_bind_params {
+ struct device_node *cooling_device;
+ unsigned int trip_id;
+ unsigned int usage;
+ unsigned long min;
+ unsigned long max;
+};
+
+/**
+ * struct __thermal_zone - internal representation of a thermal zone
+ * @mode: current thermal zone device mode (enabled/disabled)
+ * @passive_delay: polling interval while passive cooling is activated
+ * @polling_delay: zone polling interval
+ * @ntrips: number of trip points
+ * @trips: an array of trip points (0..ntrips - 1)
+ * @num_tbps: number of thermal bind params
+ * @tbps: an array of thermal bind params (0..num_tbps - 1)
+ * @sensor_data: sensor private data used while reading temperature and trend
+ * @get_temp: sensor callback to read temperature
+ * @get_trend: sensor callback to read temperature trend
+ */
+
+struct __thermal_zone {
+ enum thermal_device_mode mode;
+ int passive_delay;
+ int polling_delay;
+
+ /* trip data */
+ int ntrips;
+ struct __thermal_trip *trips;
+
+ /* cooling binding data */
+ int num_tbps;
+ struct __thermal_bind_params *tbps;
+
+ /* sensor interface */
+ void *sensor_data;
+ int (*get_temp)(void *, long *);
+ int (*get_trend)(void *, long *);
+};
+
+/*** DT thermal zone device callbacks ***/
+
+static int of_thermal_get_temp(struct thermal_zone_device *tz,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (!data->get_temp)
+ return -EINVAL;
+
+ return data->get_temp(data->sensor_data, temp);
+}
+
+static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
+ enum thermal_trend *trend)
+{
+ struct __thermal_zone *data = tz->devdata;
+ long dev_trend;
+ int r;
+
+ if (!data->get_trend)
+ return -EINVAL;
+
+ r = data->get_trend(data->sensor_data, &dev_trend);
+ if (r)
+ return r;
+
+ /* TODO: These intervals might have some thresholds, but in core code */
+ if (dev_trend > 0)
+ *trend = THERMAL_TREND_RAISING;
+ else if (dev_trend < 0)
+ *trend = THERMAL_TREND_DROPPING;
+ else
+ *trend = THERMAL_TREND_STABLE;
+
+ return 0;
+}
+
+static int of_thermal_bind(struct thermal_zone_device *thermal,
+ struct thermal_cooling_device *cdev)
+{
+ struct __thermal_zone *data = thermal->devdata;
+ int i;
+
+ if (!data || IS_ERR(data))
+ return -ENODEV;
+
+ /* find where to bind */
+ for (i = 0; i < data->num_tbps; i++) {
+ struct __thermal_bind_params *tbp = data->tbps + i;
+
+ if (tbp->cooling_device == cdev->np) {
+ int ret;
+
+ ret = thermal_zone_bind_cooling_device(thermal,
+ tbp->trip_id, cdev,
+ tbp->min,
+ tbp->max);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int of_thermal_unbind(struct thermal_zone_device *thermal,
+ struct thermal_cooling_device *cdev)
+{
+ struct __thermal_zone *data = thermal->devdata;
+ int i;
+
+ if (!data || IS_ERR(data))
+ return -ENODEV;
+
+ /* find where to unbind */
+ for (i = 0; i < data->num_tbps; i++) {
+ struct __thermal_bind_params *tbp = data->tbps + i;
+
+ if (tbp->cooling_device == cdev->np) {
+ int ret;
+
+ ret = thermal_zone_unbind_cooling_device(thermal,
+ tbp->trip_id, cdev);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int of_thermal_get_mode(struct thermal_zone_device *tz,
+ enum thermal_device_mode *mode)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ *mode = data->mode;
+
+ return 0;
+}
+
+static int of_thermal_set_mode(struct thermal_zone_device *tz,
+ enum thermal_device_mode mode)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ mutex_lock(&tz->lock);
+
+ if (mode == THERMAL_DEVICE_ENABLED)
+ tz->polling_delay = data->polling_delay;
+ else
+ tz->polling_delay = 0;
+
+ mutex_unlock(&tz->lock);
+
+ data->mode = mode;
+ thermal_zone_device_update(tz);
+
+ return 0;
+}
+
+static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
+ enum thermal_trip_type *type)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *type = data->trips[trip].type;
+
+ return 0;
+}
+
+static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *temp = data->trips[trip].temperature;
+
+ return 0;
+}
+
+static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
+ unsigned long temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ /* thermal framework should take care of data->mask & (1 << trip) */
+ data->trips[trip].temperature = temp;
+
+ return 0;
+}
+
+static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
+ unsigned long *hyst)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ *hyst = data->trips[trip].hysteresis;
+
+ return 0;
+}
+
+static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
+ unsigned long hyst)
+{
+ struct __thermal_zone *data = tz->devdata;
+
+ if (trip >= data->ntrips || trip < 0)
+ return -EDOM;
+
+ /* thermal framework should take care of data->mask & (1 << trip) */
+ data->trips[trip].hysteresis = hyst;
+
+ return 0;
+}
+
+static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
+ unsigned long *temp)
+{
+ struct __thermal_zone *data = tz->devdata;
+ int i;
+
+ for (i = 0; i < data->ntrips; i++)
+ if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
+ *temp = data->trips[i].temperature;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static struct thermal_zone_device_ops of_thermal_ops = {
+ .get_mode = of_thermal_get_mode,
+ .set_mode = of_thermal_set_mode,
+
+ .get_trip_type = of_thermal_get_trip_type,
+ .get_trip_temp = of_thermal_get_trip_temp,
+ .set_trip_temp = of_thermal_set_trip_temp,
+ .get_trip_hyst = of_thermal_get_trip_hyst,
+ .set_trip_hyst = of_thermal_set_trip_hyst,
+ .get_crit_temp = of_thermal_get_crit_temp,
+
+ .bind = of_thermal_bind,
+ .unbind = of_thermal_unbind,
+};
+
+/*** sensor API ***/
+
+static struct thermal_zone_device *
+thermal_zone_of_add_sensor(struct device_node *zone,
+ struct device_node *sensor, void *data,
+ int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ struct thermal_zone_device *tzd;
+ struct __thermal_zone *tz;
+
+ tzd = thermal_zone_get_zone_by_name(zone->name);
+ if (IS_ERR(tzd))
+ return ERR_PTR(-EPROBE_DEFER);
+
+ tz = tzd->devdata;
+
+ mutex_lock(&tzd->lock);
+ tz->get_temp = get_temp;
+ tz->get_trend = get_trend;
+ tz->sensor_data = data;
+
+ tzd->ops->get_temp = of_thermal_get_temp;
+ tzd->ops->get_trend = of_thermal_get_trend;
+ mutex_unlock(&tzd->lock);
+
+ return tzd;
+}
+
+/**
+ * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
+ * @dev: a valid struct device pointer of a sensor device. Must contain
+ * a valid .of_node, for the sensor node.
+ * @sensor_id: a sensor identifier, in case the sensor IP has more
+ * than one sensors
+ * @data: a private pointer (owned by the caller) that will be passed
+ * back, when a temperature reading is needed.
+ * @get_temp: a pointer to a function that reads the sensor temperature.
+ * @get_trend: a pointer to a function that reads the sensor temperature trend.
+ *
+ * This function will search the list of thermal zones described in device
+ * tree and look for the zone that refer to the sensor device pointed by
+ * @dev->of_node as temperature providers. For the zone pointing to the
+ * sensor node, the sensor will be added to the DT thermal zone device.
+ *
+ * The thermal zone temperature is provided by the @get_temp function
+ * pointer. When called, it will have the private pointer @data back.
+ *
+ * The thermal zone temperature trend is provided by the @get_trend function
+ * pointer. When called, it will have the private pointer @data back.
+ *
+ * TODO:
+ * 01 - This function must enqueue the new sensor instead of using
+ * it as the only source of temperature values.
+ *
+ * 02 - There must be a way to match the sensor with all thermal zones
+ * that refer to it.
+ *
+ * Return: On success returns a valid struct thermal_zone_device,
+ * otherwise, it returns a corresponding ERR_PTR(). Caller must
+ * check the return value with help of IS_ERR() helper.
+ */
+struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ struct device_node *np, *child, *sensor_np;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np)
+ return ERR_PTR(-ENODEV);
+
+ if (!dev || !dev->of_node)
+ return ERR_PTR(-EINVAL);
+
+ sensor_np = dev->of_node;
+
+ for_each_child_of_node(np, child) {
+ struct of_phandle_args sensor_specs;
+ int ret, id;
+
+ /* For now, thermal framework supports only 1 sensor per zone */
+ ret = of_parse_phandle_with_args(child, "thermal-sensors",
+ "#thermal-sensor-cells",
+ 0, &sensor_specs);
+ if (ret)
+ continue;
+
+ if (sensor_specs.args_count >= 1) {
+ id = sensor_specs.args[0];
+ WARN(sensor_specs.args_count > 1,
+ "%s: too many cells in sensor specifier %d\n",
+ sensor_specs.np->name, sensor_specs.args_count);
+ } else {
+ id = 0;
+ }
+
+ if (sensor_specs.np == sensor_np && id == sensor_id) {
+ of_node_put(np);
+ return thermal_zone_of_add_sensor(child, sensor_np,
+ data,
+ get_temp,
+ get_trend);
+ }
+ }
+ of_node_put(np);
+
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
+
+/**
+ * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
+ * @dev: a valid struct device pointer of a sensor device. Must contain
+ * a valid .of_node, for the sensor node.
+ * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
+ *
+ * This function removes the sensor callbacks and private data from the
+ * thermal zone device registered with thermal_zone_of_sensor_register()
+ * API. It will also silent the zone by remove the .get_temp() and .get_trend()
+ * thermal zone device callbacks.
+ *
+ * TODO: When the support to several sensors per zone is added, this
+ * function must search the sensor list based on @dev parameter.
+ *
+ */
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tzd)
+{
+ struct __thermal_zone *tz;
+
+ if (!dev || !tzd || !tzd->devdata)
+ return;
+
+ tz = tzd->devdata;
+
+ /* no __thermal_zone, nothing to be done */
+ if (!tz)
+ return;
+
+ mutex_lock(&tzd->lock);
+ tzd->ops->get_temp = NULL;
+ tzd->ops->get_trend = NULL;
+
+ tz->get_temp = NULL;
+ tz->get_trend = NULL;
+ tz->sensor_data = NULL;
+ mutex_unlock(&tzd->lock);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
+
+/*** functions parsing device tree nodes ***/
+
+/**
+ * thermal_of_populate_bind_params - parse and fill cooling map data
+ * @np: DT node containing a cooling-map node
+ * @__tbp: data structure to be filled with cooling map info
+ * @trips: array of thermal zone trip points
+ * @ntrips: number of trip points inside trips.
+ *
+ * This function parses a cooling-map type of node represented by
+ * @np parameter and fills the read data into @__tbp data structure.
+ * It needs the already parsed array of trip points of the thermal zone
+ * in consideration.
+ *
+ * Return: 0 on success, proper error code otherwise
+ */
+static int thermal_of_populate_bind_params(struct device_node *np,
+ struct __thermal_bind_params *__tbp,
+ struct __thermal_trip *trips,
+ int ntrips)
+{
+ struct of_phandle_args cooling_spec;
+ struct device_node *trip;
+ int ret, i;
+ u32 prop;
+
+ /* Default weight. Usage is optional */
+ __tbp->usage = 0;
+ ret = of_property_read_u32(np, "contribution", &prop);
+ if (ret == 0)
+ __tbp->usage = prop;
+
+ trip = of_parse_phandle(np, "trip", 0);
+ if (!trip) {
+ pr_err("missing trip property\n");
+ return -ENODEV;
+ }
+
+ /* match using device_node */
+ for (i = 0; i < ntrips; i++)
+ if (trip == trips[i].np) {
+ __tbp->trip_id = i;
+ break;
+ }
+
+ if (i == ntrips) {
+ ret = -ENODEV;
+ goto end;
+ }
+
+ ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
+ 0, &cooling_spec);
+ if (ret < 0) {
+ pr_err("missing cooling_device property\n");
+ goto end;
+ }
+ __tbp->cooling_device = cooling_spec.np;
+ if (cooling_spec.args_count >= 2) { /* at least min and max */
+ __tbp->min = cooling_spec.args[0];
+ __tbp->max = cooling_spec.args[1];
+ } else {
+ pr_err("wrong reference to cooling device, missing limits\n");
+ }
+
+end:
+ of_node_put(trip);
+
+ return ret;
+}
+
+/**
+ * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
+ * into the device tree binding of 'trip', property type.
+ */
+static const char * const trip_types[] = {
+ [THERMAL_TRIP_ACTIVE] = "active",
+ [THERMAL_TRIP_PASSIVE] = "passive",
+ [THERMAL_TRIP_HOT] = "hot",
+ [THERMAL_TRIP_CRITICAL] = "critical",
+};
+
+/**
+ * thermal_of_get_trip_type - Get phy mode for given device_node
+ * @np: Pointer to the given device_node
+ * @type: Pointer to resulting trip type
+ *
+ * The function gets trip type string from property 'type',
+ * and store its index in trip_types table in @type,
+ *
+ * Return: 0 on success, or errno in error case.
+ */
+static int thermal_of_get_trip_type(struct device_node *np,
+ enum thermal_trip_type *type)
+{
+ const char *t;
+ int err, i;
+
+ err = of_property_read_string(np, "type", &t);
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < ARRAY_SIZE(trip_types); i++)
+ if (!strcasecmp(t, trip_types[i])) {
+ *type = i;
+ return 0;
+ }
+
+ return -ENODEV;
+}
+
+/**
+ * thermal_of_populate_trip - parse and fill one trip point data
+ * @np: DT node containing a trip point node
+ * @trip: trip point data structure to be filled up
+ *
+ * This function parses a trip point type of node represented by
+ * @np parameter and fills the read data into @trip data structure.
+ *
+ * Return: 0 on success, proper error code otherwise
+ */
+static int thermal_of_populate_trip(struct device_node *np,
+ struct __thermal_trip *trip)
+{
+ int prop;
+ int ret;
+
+ ret = of_property_read_u32(np, "temperature", &prop);
+ if (ret < 0) {
+ pr_err("missing temperature property\n");
+ return ret;
+ }
+ trip->temperature = prop;
+
+ ret = of_property_read_u32(np, "hysteresis", &prop);
+ if (ret < 0) {
+ pr_err("missing hysteresis property\n");
+ return ret;
+ }
+ trip->hysteresis = prop;
+
+ ret = thermal_of_get_trip_type(np, &trip->type);
+ if (ret < 0) {
+ pr_err("wrong trip type property\n");
+ return ret;
+ }
+
+ /* Required for cooling map matching */
+ trip->np = np;
+
+ return 0;
+}
+
+/**
+ * thermal_of_build_thermal_zone - parse and fill one thermal zone data
+ * @np: DT node containing a thermal zone node
+ *
+ * This function parses a thermal zone type of node represented by
+ * @np parameter and fills the read data into a __thermal_zone data structure
+ * and return this pointer.
+ *
+ * TODO: Missing properties to parse: thermal-sensor-names and coefficients
+ *
+ * Return: On success returns a valid struct __thermal_zone,
+ * otherwise, it returns a corresponding ERR_PTR(). Caller must
+ * check the return value with help of IS_ERR() helper.
+ */
+static struct __thermal_zone *
+thermal_of_build_thermal_zone(struct device_node *np)
+{
+ struct device_node *child = NULL, *gchild;
+ struct __thermal_zone *tz;
+ int ret, i;
+ u32 prop;
+
+ if (!np) {
+ pr_err("no thermal zone np\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ tz = kzalloc(sizeof(*tz), GFP_KERNEL);
+ if (!tz)
+ return ERR_PTR(-ENOMEM);
+
+ ret = of_property_read_u32(np, "polling-delay-passive", &prop);
+ if (ret < 0) {
+ pr_err("missing polling-delay-passive property\n");
+ goto free_tz;
+ }
+ tz->passive_delay = prop;
+
+ ret = of_property_read_u32(np, "polling-delay", &prop);
+ if (ret < 0) {
+ pr_err("missing polling-delay property\n");
+ goto free_tz;
+ }
+ tz->polling_delay = prop;
+
+ /* trips */
+ child = of_get_child_by_name(np, "trips");
+
+ /* No trips provided */
+ if (!child)
+ goto finish;
+
+ tz->ntrips = of_get_child_count(child);
+ if (tz->ntrips == 0) /* must have at least one child */
+ goto finish;
+
+ tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
+ if (!tz->trips) {
+ ret = -ENOMEM;
+ goto free_tz;
+ }
+
+ i = 0;
+ for_each_child_of_node(child, gchild) {
+ ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
+ if (ret)
+ goto free_trips;
+ }
+
+ of_node_put(child);
+
+ /* cooling-maps */
+ child = of_get_child_by_name(np, "cooling-maps");
+
+ /* cooling-maps not provided */
+ if (!child)
+ goto finish;
+
+ tz->num_tbps = of_get_child_count(child);
+ if (tz->num_tbps == 0)
+ goto finish;
+
+ tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
+ if (!tz->tbps) {
+ ret = -ENOMEM;
+ goto free_trips;
+ }
+
+ i = 0;
+ for_each_child_of_node(child, gchild)
+ ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
+ tz->trips, tz->ntrips);
+ if (ret)
+ goto free_tbps;
+
+finish:
+ of_node_put(child);
+ tz->mode = THERMAL_DEVICE_DISABLED;
+
+ return tz;
+
+free_tbps:
+ kfree(tz->tbps);
+free_trips:
+ kfree(tz->trips);
+free_tz:
+ kfree(tz);
+ of_node_put(child);
+
+ return ERR_PTR(ret);
+}
+
+static inline void of_thermal_free_zone(struct __thermal_zone *tz)
+{
+ kfree(tz->tbps);
+ kfree(tz->trips);
+ kfree(tz);
+}
+
+/**
+ * of_parse_thermal_zones - parse device tree thermal data
+ *
+ * Initialization function that can be called by machine initialization
+ * code to parse thermal data and populate the thermal framework
+ * with hardware thermal zones info. This function only parses thermal zones.
+ * Cooling devices and sensor devices nodes are supposed to be parsed
+ * by their respective drivers.
+ *
+ * Return: 0 on success, proper error code otherwise
+ *
+ */
+int __init of_parse_thermal_zones(void)
+{
+ struct device_node *np, *child;
+ struct __thermal_zone *tz;
+ struct thermal_zone_device_ops *ops;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np) {
+ pr_debug("unable to find thermal zones\n");
+ return 0; /* Run successfully on systems without thermal DT */
+ }
+
+ for_each_child_of_node(np, child) {
+ struct thermal_zone_device *zone;
+ struct thermal_zone_params *tzp;
+
+ tz = thermal_of_build_thermal_zone(child);
+ if (IS_ERR(tz)) {
+ pr_err("failed to build thermal zone %s: %ld\n",
+ child->name,
+ PTR_ERR(tz));
+ continue;
+ }
+
+ ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
+ if (!ops)
+ goto exit_free;
+
+ tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
+ if (!tzp) {
+ kfree(ops);
+ goto exit_free;
+ }
+
+ /* No hwmon because there might be hwmon drivers registering */
+ tzp->no_hwmon = true;
+
+ zone = thermal_zone_device_register(child->name, tz->ntrips,
+ 0, tz,
+ ops, tzp,
+ tz->passive_delay,
+ tz->polling_delay);
+ if (IS_ERR(zone)) {
+ pr_err("Failed to build %s zone %ld\n", child->name,
+ PTR_ERR(zone));
+ kfree(tzp);
+ kfree(ops);
+ of_thermal_free_zone(tz);
+ /* attempting to build remaining zones still */
+ }
+ }
+
+ return 0;
+
+exit_free:
+ of_thermal_free_zone(tz);
+
+ /* no memory available, so free what we have built */
+ of_thermal_destroy_zones();
+
+ return -ENOMEM;
+}
+
+/**
+ * of_thermal_destroy_zones - remove all zones parsed and allocated resources
+ *
+ * Finds all zones parsed and added to the thermal framework and remove them
+ * from the system, together with their resources.
+ *
+ */
+void __exit of_thermal_destroy_zones(void)
+{
+ struct device_node *np, *child;
+
+ np = of_find_node_by_name(NULL, "thermal-zones");
+ if (!np) {
+ pr_err("unable to find thermal zones\n");
+ return;
+ }
+
+ for_each_child_of_node(np, child) {
+ struct thermal_zone_device *zone;
+
+ zone = thermal_zone_get_zone_by_name(child->name);
+ if (IS_ERR(zone))
+ continue;
+
+ thermal_zone_device_unregister(zone);
+ kfree(zone->tzp);
+ kfree(zone->ops);
+ of_thermal_free_zone(zone->devdata);
+ }
+}
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index f7a9f4f..fec3351 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1371,7 +1371,7 @@ static void remove_trip_attrs(struct thermal_zone_device *tz)
*/
struct thermal_zone_device *thermal_zone_device_register(const char *type,
int trips, int mask, void *devdata,
- const struct thermal_zone_device_ops *ops,
+ struct thermal_zone_device_ops *ops,
const struct thermal_zone_params *tzp,
int passive_delay, int polling_delay)
{
@@ -1751,8 +1751,14 @@ static int __init thermal_init(void)
if (result)
goto unregister_class;
+ result = of_parse_thermal_zones();
+ if (result)
+ goto exit_netlink;
+
return 0;
+exit_netlink:
+ genetlink_exit();
unregister_governors:
thermal_unregister_governors();
unregister_class:
@@ -1768,6 +1774,7 @@ error:
static void __exit thermal_exit(void)
{
+ of_thermal_destroy_zones();
genetlink_exit();
class_unregister(&thermal_class);
thermal_unregister_governors();
diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
index 7cf2f66..3db339f 100644
--- a/drivers/thermal/thermal_core.h
+++ b/drivers/thermal/thermal_core.h
@@ -77,4 +77,13 @@ static inline int thermal_gov_user_space_register(void) { return 0; }
static inline void thermal_gov_user_space_unregister(void) {}
#endif /* CONFIG_THERMAL_GOV_USER_SPACE */
+/* device tree support */
+#ifdef CONFIG_THERMAL_OF
+int of_parse_thermal_zones(void);
+void of_thermal_destroy_zones(void);
+#else
+static inline int of_parse_thermal_zones(void) { return 0; }
+static inline void of_thermal_destroy_zones(void) { }
+#endif
+
#endif /* __THERMAL_CORE_H__ */
diff --git a/include/dt-bindings/thermal/thermal.h b/include/dt-bindings/thermal/thermal.h
new file mode 100644
index 0000000..59c4581
--- /dev/null
+++ b/include/dt-bindings/thermal/thermal.h
@@ -0,0 +1,27 @@
+/*
+ * This header provides constants for most thermal bindings.
+ *
+ * Copyright (C) 2013 Texas Instruments
+ * Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
+ *
+ * GPLv2 only
+ */
+
+#ifndef _DT_BINDINGS_THERMAL_THERMAL_H
+#define _DT_BINDINGS_THERMAL_THERMAL_H
+
+/*
+ * Here are the thermal trip types. This must
+ * match with enum thermal_trip_type at
+ * include/linux/thermal.h
+ */
+#define THERMAL_TRIP_ACTIVE "active"
+#define THERMAL_TRIP_PASSIVE "passive"
+#define THERMAL_TRIP_HOT "hot"
+#define THERMAL_TRIP_CRITICAL "critical"
+
+/* On cooling devices upper and lower limits */
+#define THERMAL_NO_LIMIT (-1UL)
+
+#endif
+
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index b268d3c..b780c5b 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -143,6 +143,7 @@ struct thermal_cooling_device {
int id;
char type[THERMAL_NAME_LENGTH];
struct device device;
+ struct device_node *np;
void *devdata;
const struct thermal_cooling_device_ops *ops;
bool updated; /* true if the cooling device does not need update */
@@ -172,7 +173,7 @@ struct thermal_zone_device {
int emul_temperature;
int passive;
unsigned int forced_passive;
- const struct thermal_zone_device_ops *ops;
+ struct thermal_zone_device_ops *ops;
const struct thermal_zone_params *tzp;
struct thermal_governor *governor;
struct list_head thermal_instances;
@@ -242,8 +243,31 @@ struct thermal_genl_event {
};
/* Function declarations */
+#ifdef CONFIG_THERMAL_OF
+struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *));
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tz);
+#else
+static inline struct thermal_zone_device *
+thermal_zone_of_sensor_register(struct device *dev, int id,
+ void *data, int (*get_temp)(void *, long *),
+ int (*get_trend)(void *, long *))
+{
+ return NULL;
+}
+
+static inline
+void thermal_zone_of_sensor_unregister(struct device *dev,
+ struct thermal_zone_device *tz)
+{
+}
+
+#endif
struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
- void *, const struct thermal_zone_device_ops *,
+ void *, struct thermal_zone_device_ops *,
const struct thermal_zone_params *, int, int);
void thermal_zone_device_unregister(struct thermal_zone_device *);
--
1.8.2.1.342.gfa7285d
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^ permalink raw reply related [flat|nested] 31+ messages in thread* Re: [PATCHv8 03/18] thermal: introduce device tree parser
2013-10-01 2:39 ` [PATCHv8 " Eduardo Valentin
@ 2013-10-07 20:51 ` Mark Rutland
2013-10-08 14:59 ` Eduardo Valentin
2013-11-05 18:08 ` Eduardo Valentin
0 siblings, 2 replies; 31+ messages in thread
From: Mark Rutland @ 2013-10-07 20:51 UTC (permalink / raw)
To: Eduardo Valentin, swarren@wwwdotorg.org, Pawel Moll,
ian.campbell@citrix.com, rob.herring@calxeda.com,
grant.likely@linaro.org
Cc: linux@roeck-us.net, rui.zhang@intel.com, wni@nvidia.com,
durgadoss.r@intel.com, linux-pm@vger.kernel.org,
devicetree@vger.kernel.org, lm-sensors@lm-sensors.org,
linux-kernel@vger.kernel.org
Hi all,
Given that this is a complex new class of binding, I'd appreciate if at least
one other device tree maintainer could also take a look over this and voice any
concerns or suggestions. I've left the entire patch context for this.
Apologies for the munged whitespace -- my mail server appears to have helpfully
and irreparably replaced all tabs with spaces.
On Tue, Oct 01, 2013 at 03:39:26AM +0100, Eduardo Valentin wrote:
> This patch introduces a device tree bindings for
> describing the hardware thermal behavior and limits.
> Also a parser to read and interpret the data and feed
> it in the thermal framework is presented.
>
> This patch introduces a thermal data parser for device
> tree. The parsed data is used to build thermal zones
> and thermal binding parameters. The output data
> can then be used to deploy thermal policies.
>
> This patch adds also documentation regarding this
> API and how to define tree nodes to use
> this infrastructure.
>
> Note that, in order to be able to have control
> on the sensor registration on the DT thermal zone,
> it was required to allow changing the thermal zone
> .get_temp callback. For this reason, this patch
> also removes the 'const' modifier from the .ops
> field of thermal zone devices.
>
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: linux-pm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
> ---
> Hello Mark, folks,
>
> So, here is v8. Pretty small changes. Most are better
> English phrasing in the binding document. It follows changelog:
> - Several rephrasing in the binding document, including
> spelling, grammar and better phrasing.
> - Removed WiP warning from binding document.
> - Several spacing and formatting changes in the binding document
> - Used the '-specifier' nomenclature properly in the binding doc
> - Removed the optional property 'thermal-sensors-names', because
> it does not provide useful runtime information
> - Fixed description of 'polling-delay-passive'
> - Improved examples by adding comments and better explanation
> - s/fw/framework/g
> - Added a WARN when sensors specifiers are greater and 1.
>
> All best,
>
> Eduardo
>
> ---
> .../devicetree/bindings/thermal/thermal.txt | 587 ++++++++++++++
> drivers/thermal/Kconfig | 13 +
> drivers/thermal/Makefile | 1 +
> drivers/thermal/of-thermal.c | 849 +++++++++++++++++++++
> drivers/thermal/thermal_core.c | 9 +-
> drivers/thermal/thermal_core.h | 9 +
> include/dt-bindings/thermal/thermal.h | 27 +
> include/linux/thermal.h | 28 +-
> 8 files changed, 1520 insertions(+), 3 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
> create mode 100644 drivers/thermal/of-thermal.c
> create mode 100644 include/dt-bindings/thermal/thermal.h
>
> diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
> new file mode 100644
> index 0000000..ad06a8d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/thermal.txt
> @@ -0,0 +1,587 @@
> +* Thermal Framework Device Tree descriptor
> +
> +This file describes a generic binding to provide a way of
> +defining hardware thermal structure using device tree.
s/defining/describing/
> +A thermal structure includes thermal zones and their components,
> +such as trip points, polling intervals, sensors and cooling devices
> +binding descriptors.
> +
> +The target of device tree thermal descriptors is to describe only
> +the hardware thermal aspects. The thermal device tree bindings are
> +not about how the system must control or which algorithm or policy
> +must be taken in place.
I'm not quite sure what this is saying -- it seems to contradict the
design of the binding where trip points get linked to cooling device
configuration, and thus we're defining a policy along the lines of "when
sensor $W hits temperature $X, configure cooling device $Y with value
$Z". I don't see how that can't be considered policy.
At best, we can say that policy is being defined because describing the
physical properties of a device and dealing with this at runtime is not
feasible.
> +
> +There are five types of nodes involved to describe thermal bindings:
> +- sensors: used to describe the device source of temperature sensing;
- thermal sensors: devices which may be used to take temperature
measurements.
> +- cooling devices: used to describe devices source of power dissipation control;
- cooling devices: devices which may be used to dissipate heat.
> +- trip points: used to describe points in temperature domain defined to
> +make the system aware of hardware limits;
- trip points: describe key temperatures at which cooling is recommended. The
set of points should be chosen based on hardware limits.
> +- cooling maps: used to describe links between trip points and cooling devices;
> +- thermal zones: used to describe thermal data within the hardware;
> +
> +It follows a description of each type of these device tree nodes.
How about:
The following is a description of each of these node types.
> +
> +* Thermal sensor devices
> +
> +Thermal sensor devices are nodes providing temperature sensing capabilities on
> +thermal zones. Typical devices are I2C ADC converters and bandgaps. These are
> +nodes providing temperature data to thermal zones. Thermal sensor devices may
> +control one or more internal sensors.
> +
> +Required property:
> +- #thermal-sensor-cells: Used to provide sensor device specific information
> + Type: unsigned while referring to it. Typically 0 on thermal sensor
> + Size: one cell nodes with only one sensor, and at least 1 on nodes
> + with several internal sensors, in order
> + to identify uniquely the sensor instances within
> + the IC. See thermal zone binding for more details
> + on how consumers refer to sensor devices.
> +
> +* Cooling device nodes
> +
> +Cooling devices are nodes providing control on power dissipation. There
> +are essentially two ways to provide control on power dissipation. First
> +is by means of regulating device performance, which is known as passive
> +cooling. A typical passive cooling is a CPU that has dynamic voltage and
> +frequency scaling (DVFS), and uses lower frequencies as cooling states.
> +Second is by means of activating devices in order to remove
> +the dissipated heat, which is known as active cooling, e.g. regulating
> +fan speeds. In both cases, cooling devices shall have a way to determine
> +the state of cooling in which the device is.
I'd probably say "heat dissipation" rather than "power dissipation", unless
this is a technical term I am not aware of?
Why is the determination of the state of the cooling device important?
> +
> +Required properties:
> +- cooling-min-state: An integer indicating the smallest
> + Type: unsigned cooling state accepted. Typically 0.
> + Size: one cell
> +
> +- cooling-max-state: An integer indicating the largest
> + Type: unsigned cooling state accepted.
> + Size: one cell
> +
> +- #cooling-cells: Used to provide cooling device specific information
> + Type: unsigned while referring to it. Must be at least 2, in order
> + Size: one cell to specify minimum and maximum cooling state used
> + in the reference. The first cell is the minimum
> + cooling state requested and the second cell is
> + the maximum cooling state requested in the reference.
> + See Cooling device maps section below for more details
> + on how consumers refer to cooling devices.
Is it assumed that all the values between min and max are valid, or might this
be a sparse set of cooling values?
> +
> +* Trip points
> +
> +The trip node is a node to describe a point in the temperature domain
> +in which the system takes an action. This node describes just the point,
> +not the action.
> +
> +Required properties:
> +- temperature: An integer indicating the trip temperature level,
> + Type: signed in millicelsius.
> + Size: one cell
> +
> +- hysteresis: a (low) hysteresis value on 'temperature'. This is a
> + Type: unsigned relative value, in millicelsius.
> + Size: one cell
What is it relative to?
Why is 'temperature' in quotes?
> +
> +- type: a string containing the trip type. Supported values are:
> + "active": A trip point to enable active cooling
> + "passive": A trip point to enable passive cooling
> + "hot": A trip point to notify emergency
> + "critical": Hardware not reliable.
> + Type: string
> +
> +There are also string constants defined at
> +include/dt-bindings/thermal/thermal.h.
Why?
> +
> +* Cooling device maps
> +
> +The cooling device maps node is a node to describe how cooling devices
> +get assigned to trip points of the zone. The cooling devices are expected
> +to be loaded in the target system.
> +
> +Required properties:
> +- cooling-device: A phandle of a cooling device with its specifier,
> + Type: phandle of referring to which cooling device is used in this
> + cooling device binding. In the cooling specifier, the first cell
> + is the minimum cooling state and the second cell
> + is the maximum cooling state used in this map.
The type is wrong here -- it's a phandle + cooling-cells, not just a phandle.
> +- trip: A phandle of a trip point node within the same thermal
> + Type: phandle of zone.
> + trip point node
> +
> +Optional property:
> +- contribution: The cooling contribution to the thermal zone of the
> + Type: unsigned referred cooling device at the referred trip point.
> + Size: one cell The contribution is a ratio of the sum
> + of all cooling contributions within a thermal zone.
> +
> +Note: Using the THERMAL_NO_LIMIT (-1UL) constant in the cooling-device phandle
> +limit specifier means:
> +(i) - minimum state allowed for minimum cooling state used in the reference.
> +(ii) - maximum state allowed for maximum cooling state used in the reference.
> +Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
> +
> +* Thermal zone nodes
> +
> +The thermal zone node is the node containing all the required info
> +for describing a thermal zone, including its cooling device bindings. The
> +thermal zone node must contain, apart from its own properties, one sub-node
> +containing trip nodes and one sub-node containing all the zone cooling maps.
> +
> +Required properties:
> +- polling-delay: The maximum number of milliseconds to wait between polls
> + Type: unsigned when checking this thermal zone.
> + Size: one cell
> +
> +- polling-delay-passive: The maximum number of milliseconds to wait
> + Type: unsigned between polls when performing passive cooling.
> + Size: one cell
> +
> +- thermal-sensors: A list of thermal sensor phandles and sensor specifier
> + Type: list of used while monitoring the thermal zone.
> + sensor phandles
The type is wrong here. A list of phandle + sensor specifiers.
> +
> +- trips: A sub-node which is a container of only trip point nodes
> + Type: sub-node required to describe the thermal zone.
> +
> +- cooling-maps: A sub-node which is a container of only cooling device
> + Type: sub-node map nodes, used to describe the relation between trips
> + and cooling devices.
> +
> +Optional property:
> +- coefficients: An array of integers (one signed cell) containing
> + Type: array coefficients to compose a linear relation between
> + Elem size: one cell the sensors listed in the thermal-sensors property.
> + Elem type: signed Coefficients defaults to 1, in case this property
> + is not specified. A simple linear polynomial is used:
> + Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
> +
> + The coefficients are ordered and they match with sensors
> + by means of sensor ID. Additional coefficients are
> + interpreted as constant offset.
> +
> +Note: The delay properties are bound to the maximum dT/dt (temperature
> +derivative over time) in two situations for a thermal zone:
> +(i) - when passive cooling is activated (polling-delay-passive); and
> +(ii) - when the zone just needs to be monitored (polling-delay) or
> +when active cooling is activated.
> +
> +The maximum dT/dt is highly bound to hardware power consumption and dissipation
> +capability. The delays should be chosen to account for said max dT/dt,
> +such that a device does not cross several trip boundaries unexpectedly
> +between polls. Choosing the right polling delays shall avoid having the
> +device in temperature ranges that may damage the silicon structures and
> +reduce silicon lifetime.
> +
> +* The thermal-zones node
> +
> +The "thermal-zones" node is a container for all thermal zone nodes. It shall
> +contain only sub-nodes describing thermal zones as in the section
> +"Thermal zone nodes". The "thermal-zones" node appears under "/".
> +
> +* Examples
> +
> +Below are several examples on how to use thermal data descriptors
> +using device tree bindings:
> +
> +(a) - CPU thermal zone
> +
> +The CPU thermal zone example below describes how to setup one thermal zone
> +using one single sensor as temperature source and many cooling devices and
> +power dissipation control sources.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +cpus {
> + /*
> + * Here is an example of describing a cooling device for a DVFS
> + * capable CPU. The CPU node describes its four OPPs.
> + * The cooling states possible are 0..3, and they are
> + * used as OPP indexes. The minimum cooling state is 0, which means
> + * all four OPPs can be available to the system. The maximum
> + * cooling state is 3, which means only the lowest OPPs (198MHz@0.85V)
> + * can be available in the system.
> + */
> + cpu0: cpu@0 {
> + ...
> + operating-points = <
> + /* kHz uV */
> + 970000 1200000
> + 792000 1100000
> + 396000 950000
> + 198000 850000
> + >;
> + cooling-min-state = <0>;
> + cooling-max-state = <3>;
> + #cooling-cells = <2>; /* min followed by max */
> + };
> + ...
> +};
> +
> +&i2c1 {
> + ...
> + /*
> + * A simple fan controller which supports 10 speeds of operation
> + * (represented as 0-9).
> + */
> + fan0: fan@0x48 {
> + ...
> + cooling-min-state = <0>;
> + cooling-max-state = <9>;
> + #cooling-cells = <2>; /* min followed by max */
> + };
> +};
> +
> +ocp {
> + ...
> + /*
> + * A simple IC with a single bandgap temperature sensor.
> + */
> + bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <0>;
> + };
> +};
> +
> +thermal-zones {
> + cpu-thermal: cpu-thermal {
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + thermal-sensors = <&bandgap0>;
> +
> + trips {
> + cpu-alert0: cpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "active";
> + };
> + cpu-alert1: cpu-alert {
> + temperature = <100000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + cpu-crit: cpu-crit {
> + temperature = <125000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "critical";
> + };
> + };
> +
> + cooling-maps {
> + map0 {
> + trip = <&cpu-alert0>;
> + cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
> + };
> + map1 {
> + trip = <&cpu-alert1>;
> + cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
> + };
> + map2 {
> + trip = <&cpu-alert1>;
> + cooling-device =
> + <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
> + };
> + };
> + };
> +};
> +
> +In the example above, the ADC sensor (bandgap0) at address 0x0000ED00 is
> +used to monitor the zone 'cpu-thermal' using its sole sensor. A fan
> +device (fan0) is controlled via I2C bus 1, at address 0x48, and has ten
> +different cooling states 0-9. It is used to remove the heat out of
> +the thermal zone 'cpu-thermal' using its cooling states
> +from its minimum to 4, when it reaches trip point 'cpu-alert0'
> +at 90C, as an example of active cooling. The same cooling device is used at
> +'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
> +linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
> +using all its cooling states at trip point 'cpu-alert1',
> +which is a trip point at 100C. On the thermal zone 'cpu-thermal', at the
> +temperature of 125C, represented by the trip point 'cpu-crit', the silicon
> +is not reliable anymore.
> +
> +(b) - IC with several internal sensors
> +
> +The example below describes how to deploy several thermal zones based off a
> +single sensor IC, assuming it has several internal sensors. This is a common
> +case on SoC designs with several internal IPs that may need different thermal
> +requirements, and thus may have their own sensor to monitor or detect internal
> +hotspots in their silicon.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +ocp {
> + ...
> + /*
> + * A simple IC with several bandgap temperature sensors.
> + */
> + bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <1>;
> + };
> +};
> +
> +thermal-zones {
> + cpu-thermal: cpu-thermal {
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 0>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + cpu-alert: cpu-alert {
> + temperature = <100000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + cpu-crit: cpu-crit {
> + temperature = <125000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "critical";
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> + };
> +
> + gpu-thermal: gpu-thermal {
> + polling-delay-passive = <120>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 1>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + gpu-alert: gpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + gpu-crit: gpu-crit {
> + temperature = <105000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "critical";
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> + };
> +
> + dsp-thermal: dsp-thermal {
> + polling-delay-passive = <50>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&bandgap0 2>;
> +
> + trips {
> + /* each zone within the SoC may have its own trips */
> + dsp-alert: gpu-alert {
> + temperature = <90000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + dsp-crit: gpu-crit {
> + temperature = <135000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "critical";
> + };
> + };
> +
> + cooling-maps {
> + /* each zone within the SoC may have its own cooling */
> + ...
> + };
> + };
> +};
> +
> +In the example above, there is one bandgap IC which has the capability to
> +monitor three sensors. The hardware has been designed so that sensors are
> +placed on different places in the DIE to monitor different temperature
> +hotspots: one for CPU thermal zone, one for GPU thermal zone and the
> +other to monitor a DSP thermal zone.
> +
> +Thus, there is a need to assign each sensor provided by the bandgap IC
> +to different thermal zones. This is achieved by means of using the
> +#thermal-sensor-cells property and using the first cell of the sensor
> +specifier as sensor ID. In the example, then, <bandgap 0> is used to
> +monitor CPU thermal zone, <bandgap 1> is used to monitor GPU thermal
> +zone and <bandgap 2> is used to monitor DSP thermal zone. Each zone
> +may be uncorrelated, having its own dT/dt requirements, trips
> +and cooling maps.
> +
> +
> +(c) - Several sensors within one single thermal zone
> +
> +The example below illustrates how to use more than one sensor within
> +one thermal zone.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +&i2c1 {
> + ...
> + /*
> + * A simple IC with a single temperature sensor.
> + */
> + adc: sensor@0x49 {
> + ...
> + #thermal-sensor-cells = <0>;
> + };
> +};
> +
> +ocp {
> + ...
> + /*
> + * A simple IC with a single bandgap temperature sensor.
> + */
> + bandgap0: bandgap@0x0000ED00 {
> + ...
> + #thermal-sensor-cells = <0>;
> + };
> +};
> +
> +thermal-zones {
> + cpu-thermal: cpu-thermal {
> + polling-delay-passive = <250>; /* milliseconds */
> + polling-delay = <1000>; /* milliseconds */
> +
> + thermal-sensors = <&bandgap0>, /* cpu */
> + <&adc>; /* pcb north */
> +
> + /* hotspot = 100 * bandgap - 120 * adc + 484 */
> + coefficients = <100 -120 484>;
> +
> + trips {
> + ...
> + };
> +
> + cooling-maps {
> + ...
> + };
> + };
> +};
> +
> +In some cases, there is a need to use more than one sensor to extrapolate
> +a thermal hotspot in the silicon. The above example illustrates this situation.
> +For instance, it may be the case that a sensor external to CPU IP may be placed
> +close to CPU hotspot and together with internal CPU sensor, it is used
> +to determine the hotspot. Assuming this is the case for the above example,
> +the hypothetical extrapolation rule would be:
> + hotspot = 100 * bandgap - 120 * adc + 484
> +
> +In other context, the same idea can be used to add fixed offset. For instance,
> +consider the hotspot extrapolation rule below:
> + hotspot = 1 * adc + 6000
> +
> +In the above equation, the hotspot is always 6C higher than what is read
> +from the ADC sensor. The binding would be then:
> + thermal-sensors = <&adc>;
> +
> + /* hotspot = 1 * adc + 6000 */
> + coefficients = <1 6000>;
> +
> +(d) - Board thermal
> +
> +The board thermal example below illustrates how to setup one thermal zone
> +with many sensors and many cooling devices.
> +
> +#include <dt-bindings/thermal/thermal.h>
> +
> +&i2c1 {
> + ...
> + /*
> + * An IC with several temperature sensor.
> + */
> + adc-dummy: sensor@0x50 {
> + ...
> + #thermal-sensor-cells = <1>; /* sensor internal ID */
> + };
> +};
> +
> +thermal-zones {
> + batt-thermal {
> + polling-delay-passive = <500>; /* milliseconds */
> + polling-delay = <2500>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&adc-dummy 4>;
> +
> + trips {
> + ...
> + };
> +
> + cooling-maps {
> + ...
> + };
> + };
> +
> + board-thermal: board-thermal {
> + polling-delay-passive = <1000>; /* milliseconds */
> + polling-delay = <2500>; /* milliseconds */
> +
> + /* sensor ID */
> + thermal-sensors = <&adc-dummy 0>, /* pcb top edge */
> + <&adc-dummy 1>, /* lcd */
> + <&adc-dymmy 2>; /* back cover */
> + /*
> + * An array of coefficients describing the sensor
> + * linear relation. E.g.:
> + * z = c1*x1 + c2*x2 + c3*x3
> + */
> + coefficients = <1200 -345 890>;
> +
> + trips {
> + /* Trips are based on resulting linear equation */
> + cpu-trip: cpu-trip {
> + temperature = <60000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + gpu-trip: gpu-trip {
> + temperature = <55000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + }
> + lcd-trip: lcp-trip {
> + temperature = <53000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "passive";
> + };
> + crit-trip: crit-trip {
> + temperature = <68000>; /* millicelsius */
> + hysteresis = <2000>; /* millicelsius */
> + type = "critical";
> + };
> + };
> +
> + cooling-maps {
> + map0 {
> + trip = <&cpu-trip>;
> + cooling-device = <&cpu0 0 2>;
> + contribution = <55>;
> + };
> + map1 {
> + trip = <&gpu-trip>;
> + cooling-device = <&gpu0 0 2>;
> + contribution = <20>;
> + };
> + map2 {
> + trip = <&lcd-trip>;
> + cooling-device = <&lcd0 5 10>;
> + contribution = <15>;
> + };
> + };
> + };
> +};
> +
> +The above example is a mix of previous examples, a sensor IP with several internal
> +sensors used to monitor different zones, one of them is composed by several sensors and
> +with different cooling devices.
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index dbfc390..dd81eb8 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -29,6 +29,19 @@ config THERMAL_HWMON
> Say 'Y' here if you want all thermal sensors to
> have hwmon sysfs interface too.
>
> +config THERMAL_OF
> + bool
> + prompt "APIs to parse thermal data out of device tree"
> + depends on OF
> + default y
> + help
> + This options provides helpers to add the support to
> + read and parse thermal data definitions out of the
> + device tree blob.
> +
> + Say 'Y' here if you need to build thermal infrastructure
> + based on device tree.
> +
> choice
> prompt "Default Thermal governor"
> default THERMAL_DEFAULT_GOV_STEP_WISE
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 584b363..4b03956 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -7,6 +7,7 @@ thermal_sys-y += thermal_core.o
>
> # interface to/from other layers providing sensors
> thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
> +thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
>
> # governors
> thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
> diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
> new file mode 100644
> index 0000000..66f9eb2
> --- /dev/null
> +++ b/drivers/thermal/of-thermal.c
> @@ -0,0 +1,849 @@
> +/*
> + * of-thermal.c - Generic Thermal Management device tree support.
> + *
> + * Copyright (C) 2013 Texas Instruments
> + * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
> + *
> + *
> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
> + *
> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + */
> +#include <linux/thermal.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/err.h>
> +#include <linux/export.h>
> +#include <linux/string.h>
> +
> +#include "thermal_core.h"
> +
> +/*** Private data structures to represent thermal device tree data ***/
> +
> +/**
> + * struct __thermal_trip - representation of a point in temperature domain
> + * @np: pointer to struct device_node that this trip point was created from
> + * @temperature: temperature value in miliCelsius
> + * @hysteresis: relative hysteresis in miliCelsius
> + * @type: trip point type
> + */
> +
> +struct __thermal_trip {
> + struct device_node *np;
> + unsigned long int temperature;
> + unsigned long int hysteresis;
> + enum thermal_trip_type type;
> +};
> +
> +/**
> + * struct __thermal_bind_param - a match between trip and cooling device
> + * @cooling_device: a pointer to identify the referred cooling device
> + * @trip_id: the trip point index
> + * @usage: the percentage (from 0 to 100) of cooling contribution
> + * @min: minimum cooling state used at this trip point
> + * @max: maximum cooling state used at this trip point
> + */
> +
> +struct __thermal_bind_params {
> + struct device_node *cooling_device;
> + unsigned int trip_id;
> + unsigned int usage;
> + unsigned long min;
> + unsigned long max;
> +};
> +
> +/**
> + * struct __thermal_zone - internal representation of a thermal zone
> + * @mode: current thermal zone device mode (enabled/disabled)
> + * @passive_delay: polling interval while passive cooling is activated
> + * @polling_delay: zone polling interval
> + * @ntrips: number of trip points
> + * @trips: an array of trip points (0..ntrips - 1)
> + * @num_tbps: number of thermal bind params
> + * @tbps: an array of thermal bind params (0..num_tbps - 1)
> + * @sensor_data: sensor private data used while reading temperature and trend
> + * @get_temp: sensor callback to read temperature
> + * @get_trend: sensor callback to read temperature trend
> + */
> +
> +struct __thermal_zone {
> + enum thermal_device_mode mode;
> + int passive_delay;
> + int polling_delay;
> +
> + /* trip data */
> + int ntrips;
> + struct __thermal_trip *trips;
> +
> + /* cooling binding data */
> + int num_tbps;
> + struct __thermal_bind_params *tbps;
> +
> + /* sensor interface */
> + void *sensor_data;
> + int (*get_temp)(void *, long *);
> + int (*get_trend)(void *, long *);
> +};
> +
> +/*** DT thermal zone device callbacks ***/
> +
> +static int of_thermal_get_temp(struct thermal_zone_device *tz,
> + unsigned long *temp)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (!data->get_temp)
> + return -EINVAL;
> +
> + return data->get_temp(data->sensor_data, temp);
> +}
> +
> +static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
> + enum thermal_trend *trend)
> +{
> + struct __thermal_zone *data = tz->devdata;
> + long dev_trend;
> + int r;
> +
> + if (!data->get_trend)
> + return -EINVAL;
> +
> + r = data->get_trend(data->sensor_data, &dev_trend);
> + if (r)
> + return r;
> +
> + /* TODO: These intervals might have some thresholds, but in core code */
> + if (dev_trend > 0)
> + *trend = THERMAL_TREND_RAISING;
> + else if (dev_trend < 0)
> + *trend = THERMAL_TREND_DROPPING;
> + else
> + *trend = THERMAL_TREND_STABLE;
> +
> + return 0;
> +}
> +
> +static int of_thermal_bind(struct thermal_zone_device *thermal,
> + struct thermal_cooling_device *cdev)
> +{
> + struct __thermal_zone *data = thermal->devdata;
> + int i;
> +
> + if (!data || IS_ERR(data))
> + return -ENODEV;
> +
> + /* find where to bind */
> + for (i = 0; i < data->num_tbps; i++) {
> + struct __thermal_bind_params *tbp = data->tbps + i;
> +
> + if (tbp->cooling_device == cdev->np) {
> + int ret;
> +
> + ret = thermal_zone_bind_cooling_device(thermal,
> + tbp->trip_id, cdev,
> + tbp->min,
> + tbp->max);
> + if (ret)
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int of_thermal_unbind(struct thermal_zone_device *thermal,
> + struct thermal_cooling_device *cdev)
> +{
> + struct __thermal_zone *data = thermal->devdata;
> + int i;
> +
> + if (!data || IS_ERR(data))
> + return -ENODEV;
> +
> + /* find where to unbind */
> + for (i = 0; i < data->num_tbps; i++) {
> + struct __thermal_bind_params *tbp = data->tbps + i;
> +
> + if (tbp->cooling_device == cdev->np) {
> + int ret;
> +
> + ret = thermal_zone_unbind_cooling_device(thermal,
> + tbp->trip_id, cdev);
> + if (ret)
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int of_thermal_get_mode(struct thermal_zone_device *tz,
> + enum thermal_device_mode *mode)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + *mode = data->mode;
> +
> + return 0;
> +}
> +
> +static int of_thermal_set_mode(struct thermal_zone_device *tz,
> + enum thermal_device_mode mode)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + mutex_lock(&tz->lock);
> +
> + if (mode == THERMAL_DEVICE_ENABLED)
> + tz->polling_delay = data->polling_delay;
> + else
> + tz->polling_delay = 0;
> +
> + mutex_unlock(&tz->lock);
> +
> + data->mode = mode;
> + thermal_zone_device_update(tz);
> +
> + return 0;
> +}
> +
> +static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
> + enum thermal_trip_type *type)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + *type = data->trips[trip].type;
> +
> + return 0;
> +}
> +
> +static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
> + unsigned long *temp)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + *temp = data->trips[trip].temperature;
> +
> + return 0;
> +}
> +
> +static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
> + unsigned long temp)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + /* thermal framework should take care of data->mask & (1 << trip) */
> + data->trips[trip].temperature = temp;
> +
> + return 0;
> +}
> +
> +static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
> + unsigned long *hyst)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + *hyst = data->trips[trip].hysteresis;
> +
> + return 0;
> +}
> +
> +static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
> + unsigned long hyst)
> +{
> + struct __thermal_zone *data = tz->devdata;
> +
> + if (trip >= data->ntrips || trip < 0)
> + return -EDOM;
> +
> + /* thermal framework should take care of data->mask & (1 << trip) */
> + data->trips[trip].hysteresis = hyst;
> +
> + return 0;
> +}
> +
> +static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
> + unsigned long *temp)
> +{
> + struct __thermal_zone *data = tz->devdata;
> + int i;
> +
> + for (i = 0; i < data->ntrips; i++)
> + if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
> + *temp = data->trips[i].temperature;
> + return 0;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static struct thermal_zone_device_ops of_thermal_ops = {
> + .get_mode = of_thermal_get_mode,
> + .set_mode = of_thermal_set_mode,
> +
> + .get_trip_type = of_thermal_get_trip_type,
> + .get_trip_temp = of_thermal_get_trip_temp,
> + .set_trip_temp = of_thermal_set_trip_temp,
> + .get_trip_hyst = of_thermal_get_trip_hyst,
> + .set_trip_hyst = of_thermal_set_trip_hyst,
> + .get_crit_temp = of_thermal_get_crit_temp,
> +
> + .bind = of_thermal_bind,
> + .unbind = of_thermal_unbind,
> +};
> +
> +/*** sensor API ***/
> +
> +static struct thermal_zone_device *
> +thermal_zone_of_add_sensor(struct device_node *zone,
> + struct device_node *sensor, void *data,
> + int (*get_temp)(void *, long *),
> + int (*get_trend)(void *, long *))
> +{
> + struct thermal_zone_device *tzd;
> + struct __thermal_zone *tz;
> +
> + tzd = thermal_zone_get_zone_by_name(zone->name);
> + if (IS_ERR(tzd))
> + return ERR_PTR(-EPROBE_DEFER);
> +
> + tz = tzd->devdata;
> +
> + mutex_lock(&tzd->lock);
> + tz->get_temp = get_temp;
> + tz->get_trend = get_trend;
> + tz->sensor_data = data;
> +
> + tzd->ops->get_temp = of_thermal_get_temp;
> + tzd->ops->get_trend = of_thermal_get_trend;
> + mutex_unlock(&tzd->lock);
> +
> + return tzd;
> +}
> +
> +/**
> + * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
> + * @dev: a valid struct device pointer of a sensor device. Must contain
> + * a valid .of_node, for the sensor node.
> + * @sensor_id: a sensor identifier, in case the sensor IP has more
> + * than one sensors
> + * @data: a private pointer (owned by the caller) that will be passed
> + * back, when a temperature reading is needed.
> + * @get_temp: a pointer to a function that reads the sensor temperature.
> + * @get_trend: a pointer to a function that reads the sensor temperature trend.
> + *
> + * This function will search the list of thermal zones described in device
> + * tree and look for the zone that refer to the sensor device pointed by
> + * @dev->of_node as temperature providers. For the zone pointing to the
> + * sensor node, the sensor will be added to the DT thermal zone device.
> + *
> + * The thermal zone temperature is provided by the @get_temp function
> + * pointer. When called, it will have the private pointer @data back.
> + *
> + * The thermal zone temperature trend is provided by the @get_trend function
> + * pointer. When called, it will have the private pointer @data back.
> + *
> + * TODO:
> + * 01 - This function must enqueue the new sensor instead of using
> + * it as the only source of temperature values.
> + *
> + * 02 - There must be a way to match the sensor with all thermal zones
> + * that refer to it.
> + *
> + * Return: On success returns a valid struct thermal_zone_device,
> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
> + * check the return value with help of IS_ERR() helper.
> + */
> +struct thermal_zone_device *
> +thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
> + void *data, int (*get_temp)(void *, long *),
> + int (*get_trend)(void *, long *))
> +{
> + struct device_node *np, *child, *sensor_np;
> +
> + np = of_find_node_by_name(NULL, "thermal-zones");
> + if (!np)
> + return ERR_PTR(-ENODEV);
> +
> + if (!dev || !dev->of_node)
> + return ERR_PTR(-EINVAL);
> +
> + sensor_np = dev->of_node;
> +
> + for_each_child_of_node(np, child) {
> + struct of_phandle_args sensor_specs;
> + int ret, id;
> +
> + /* For now, thermal framework supports only 1 sensor per zone */
> + ret = of_parse_phandle_with_args(child, "thermal-sensors",
> + "#thermal-sensor-cells",
> + 0, &sensor_specs);
> + if (ret)
> + continue;
> +
> + if (sensor_specs.args_count >= 1) {
> + id = sensor_specs.args[0];
> + WARN(sensor_specs.args_count > 1,
> + "%s: too many cells in sensor specifier %d\n",
> + sensor_specs.np->name, sensor_specs.args_count);
> + } else {
> + id = 0;
> + }
> +
> + if (sensor_specs.np == sensor_np && id == sensor_id) {
> + of_node_put(np);
> + return thermal_zone_of_add_sensor(child, sensor_np,
> + data,
> + get_temp,
> + get_trend);
> + }
> + }
> + of_node_put(np);
> +
> + return ERR_PTR(-ENODEV);
> +}
> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
> +
> +/**
> + * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
> + * @dev: a valid struct device pointer of a sensor device. Must contain
> + * a valid .of_node, for the sensor node.
> + * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
> + *
> + * This function removes the sensor callbacks and private data from the
> + * thermal zone device registered with thermal_zone_of_sensor_register()
> + * API. It will also silent the zone by remove the .get_temp() and .get_trend()
> + * thermal zone device callbacks.
> + *
> + * TODO: When the support to several sensors per zone is added, this
> + * function must search the sensor list based on @dev parameter.
> + *
> + */
> +void thermal_zone_of_sensor_unregister(struct device *dev,
> + struct thermal_zone_device *tzd)
> +{
> + struct __thermal_zone *tz;
> +
> + if (!dev || !tzd || !tzd->devdata)
> + return;
> +
> + tz = tzd->devdata;
> +
> + /* no __thermal_zone, nothing to be done */
> + if (!tz)
> + return;
> +
> + mutex_lock(&tzd->lock);
> + tzd->ops->get_temp = NULL;
> + tzd->ops->get_trend = NULL;
> +
> + tz->get_temp = NULL;
> + tz->get_trend = NULL;
> + tz->sensor_data = NULL;
> + mutex_unlock(&tzd->lock);
> +}
> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
> +
> +/*** functions parsing device tree nodes ***/
> +
> +/**
> + * thermal_of_populate_bind_params - parse and fill cooling map data
> + * @np: DT node containing a cooling-map node
> + * @__tbp: data structure to be filled with cooling map info
> + * @trips: array of thermal zone trip points
> + * @ntrips: number of trip points inside trips.
> + *
> + * This function parses a cooling-map type of node represented by
> + * @np parameter and fills the read data into @__tbp data structure.
> + * It needs the already parsed array of trip points of the thermal zone
> + * in consideration.
> + *
> + * Return: 0 on success, proper error code otherwise
> + */
> +static int thermal_of_populate_bind_params(struct device_node *np,
> + struct __thermal_bind_params *__tbp,
> + struct __thermal_trip *trips,
> + int ntrips)
> +{
> + struct of_phandle_args cooling_spec;
> + struct device_node *trip;
> + int ret, i;
> + u32 prop;
> +
> + /* Default weight. Usage is optional */
> + __tbp->usage = 0;
> + ret = of_property_read_u32(np, "contribution", &prop);
> + if (ret == 0)
> + __tbp->usage = prop;
> +
> + trip = of_parse_phandle(np, "trip", 0);
> + if (!trip) {
> + pr_err("missing trip property\n");
> + return -ENODEV;
> + }
> +
> + /* match using device_node */
> + for (i = 0; i < ntrips; i++)
> + if (trip == trips[i].np) {
> + __tbp->trip_id = i;
> + break;
> + }
> +
> + if (i == ntrips) {
> + ret = -ENODEV;
> + goto end;
> + }
> +
> + ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
> + 0, &cooling_spec);
> + if (ret < 0) {
> + pr_err("missing cooling_device property\n");
> + goto end;
> + }
> + __tbp->cooling_device = cooling_spec.np;
> + if (cooling_spec.args_count >= 2) { /* at least min and max */
> + __tbp->min = cooling_spec.args[0];
> + __tbp->max = cooling_spec.args[1];
> + } else {
> + pr_err("wrong reference to cooling device, missing limits\n");
> + }
> +
> +end:
> + of_node_put(trip);
> +
> + return ret;
> +}
> +
> +/**
> + * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
> + * into the device tree binding of 'trip', property type.
> + */
> +static const char * const trip_types[] = {
> + [THERMAL_TRIP_ACTIVE] = "active",
> + [THERMAL_TRIP_PASSIVE] = "passive",
> + [THERMAL_TRIP_HOT] = "hot",
> + [THERMAL_TRIP_CRITICAL] = "critical",
> +};
> +
> +/**
> + * thermal_of_get_trip_type - Get phy mode for given device_node
> + * @np: Pointer to the given device_node
> + * @type: Pointer to resulting trip type
> + *
> + * The function gets trip type string from property 'type',
> + * and store its index in trip_types table in @type,
> + *
> + * Return: 0 on success, or errno in error case.
> + */
> +static int thermal_of_get_trip_type(struct device_node *np,
> + enum thermal_trip_type *type)
> +{
> + const char *t;
> + int err, i;
> +
> + err = of_property_read_string(np, "type", &t);
> + if (err < 0)
> + return err;
> +
> + for (i = 0; i < ARRAY_SIZE(trip_types); i++)
> + if (!strcasecmp(t, trip_types[i])) {
> + *type = i;
> + return 0;
> + }
> +
> + return -ENODEV;
> +}
> +
> +/**
> + * thermal_of_populate_trip - parse and fill one trip point data
> + * @np: DT node containing a trip point node
> + * @trip: trip point data structure to be filled up
> + *
> + * This function parses a trip point type of node represented by
> + * @np parameter and fills the read data into @trip data structure.
> + *
> + * Return: 0 on success, proper error code otherwise
> + */
> +static int thermal_of_populate_trip(struct device_node *np,
> + struct __thermal_trip *trip)
> +{
> + int prop;
> + int ret;
> +
> + ret = of_property_read_u32(np, "temperature", &prop);
> + if (ret < 0) {
> + pr_err("missing temperature property\n");
> + return ret;
> + }
> + trip->temperature = prop;
> +
> + ret = of_property_read_u32(np, "hysteresis", &prop);
> + if (ret < 0) {
> + pr_err("missing hysteresis property\n");
> + return ret;
> + }
> + trip->hysteresis = prop;
> +
> + ret = thermal_of_get_trip_type(np, &trip->type);
> + if (ret < 0) {
> + pr_err("wrong trip type property\n");
> + return ret;
> + }
> +
> + /* Required for cooling map matching */
> + trip->np = np;
> +
> + return 0;
> +}
> +
> +/**
> + * thermal_of_build_thermal_zone - parse and fill one thermal zone data
> + * @np: DT node containing a thermal zone node
> + *
> + * This function parses a thermal zone type of node represented by
> + * @np parameter and fills the read data into a __thermal_zone data structure
> + * and return this pointer.
> + *
> + * TODO: Missing properties to parse: thermal-sensor-names and coefficients
> + *
> + * Return: On success returns a valid struct __thermal_zone,
> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
> + * check the return value with help of IS_ERR() helper.
> + */
> +static struct __thermal_zone *
> +thermal_of_build_thermal_zone(struct device_node *np)
> +{
> + struct device_node *child = NULL, *gchild;
> + struct __thermal_zone *tz;
> + int ret, i;
> + u32 prop;
> +
> + if (!np) {
> + pr_err("no thermal zone np\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + tz = kzalloc(sizeof(*tz), GFP_KERNEL);
> + if (!tz)
> + return ERR_PTR(-ENOMEM);
> +
> + ret = of_property_read_u32(np, "polling-delay-passive", &prop);
> + if (ret < 0) {
> + pr_err("missing polling-delay-passive property\n");
> + goto free_tz;
> + }
> + tz->passive_delay = prop;
> +
> + ret = of_property_read_u32(np, "polling-delay", &prop);
> + if (ret < 0) {
> + pr_err("missing polling-delay property\n");
> + goto free_tz;
> + }
> + tz->polling_delay = prop;
> +
> + /* trips */
> + child = of_get_child_by_name(np, "trips");
> +
> + /* No trips provided */
> + if (!child)
> + goto finish;
> +
> + tz->ntrips = of_get_child_count(child);
> + if (tz->ntrips == 0) /* must have at least one child */
> + goto finish;
> +
> + tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
> + if (!tz->trips) {
> + ret = -ENOMEM;
> + goto free_tz;
> + }
> +
> + i = 0;
> + for_each_child_of_node(child, gchild) {
> + ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
> + if (ret)
> + goto free_trips;
> + }
> +
> + of_node_put(child);
> +
> + /* cooling-maps */
> + child = of_get_child_by_name(np, "cooling-maps");
> +
> + /* cooling-maps not provided */
> + if (!child)
> + goto finish;
> +
> + tz->num_tbps = of_get_child_count(child);
> + if (tz->num_tbps == 0)
> + goto finish;
> +
> + tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
> + if (!tz->tbps) {
> + ret = -ENOMEM;
> + goto free_trips;
> + }
> +
> + i = 0;
> + for_each_child_of_node(child, gchild)
> + ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
> + tz->trips, tz->ntrips);
> + if (ret)
> + goto free_tbps;
> +
> +finish:
> + of_node_put(child);
> + tz->mode = THERMAL_DEVICE_DISABLED;
> +
> + return tz;
> +
> +free_tbps:
> + kfree(tz->tbps);
> +free_trips:
> + kfree(tz->trips);
> +free_tz:
> + kfree(tz);
> + of_node_put(child);
> +
> + return ERR_PTR(ret);
> +}
> +
> +static inline void of_thermal_free_zone(struct __thermal_zone *tz)
> +{
> + kfree(tz->tbps);
> + kfree(tz->trips);
> + kfree(tz);
> +}
> +
> +/**
> + * of_parse_thermal_zones - parse device tree thermal data
> + *
> + * Initialization function that can be called by machine initialization
> + * code to parse thermal data and populate the thermal framework
> + * with hardware thermal zones info. This function only parses thermal zones.
> + * Cooling devices and sensor devices nodes are supposed to be parsed
> + * by their respective drivers.
> + *
> + * Return: 0 on success, proper error code otherwise
> + *
> + */
> +int __init of_parse_thermal_zones(void)
> +{
> + struct device_node *np, *child;
> + struct __thermal_zone *tz;
> + struct thermal_zone_device_ops *ops;
> +
> + np = of_find_node_by_name(NULL, "thermal-zones");
> + if (!np) {
> + pr_debug("unable to find thermal zones\n");
> + return 0; /* Run successfully on systems without thermal DT */
> + }
> +
> + for_each_child_of_node(np, child) {
> + struct thermal_zone_device *zone;
> + struct thermal_zone_params *tzp;
> +
> + tz = thermal_of_build_thermal_zone(child);
> + if (IS_ERR(tz)) {
> + pr_err("failed to build thermal zone %s: %ld\n",
> + child->name,
> + PTR_ERR(tz));
> + continue;
> + }
> +
> + ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
> + if (!ops)
> + goto exit_free;
> +
> + tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
> + if (!tzp) {
> + kfree(ops);
> + goto exit_free;
> + }
> +
> + /* No hwmon because there might be hwmon drivers registering */
> + tzp->no_hwmon = true;
> +
> + zone = thermal_zone_device_register(child->name, tz->ntrips,
> + 0, tz,
> + ops, tzp,
> + tz->passive_delay,
> + tz->polling_delay);
> + if (IS_ERR(zone)) {
> + pr_err("Failed to build %s zone %ld\n", child->name,
> + PTR_ERR(zone));
> + kfree(tzp);
> + kfree(ops);
> + of_thermal_free_zone(tz);
> + /* attempting to build remaining zones still */
> + }
> + }
> +
> + return 0;
> +
> +exit_free:
> + of_thermal_free_zone(tz);
> +
> + /* no memory available, so free what we have built */
> + of_thermal_destroy_zones();
> +
> + return -ENOMEM;
> +}
> +
> +/**
> + * of_thermal_destroy_zones - remove all zones parsed and allocated resources
> + *
> + * Finds all zones parsed and added to the thermal framework and remove them
> + * from the system, together with their resources.
> + *
> + */
> +void __exit of_thermal_destroy_zones(void)
> +{
> + struct device_node *np, *child;
> +
> + np = of_find_node_by_name(NULL, "thermal-zones");
> + if (!np) {
> + pr_err("unable to find thermal zones\n");
> + return;
> + }
> +
> + for_each_child_of_node(np, child) {
> + struct thermal_zone_device *zone;
> +
> + zone = thermal_zone_get_zone_by_name(child->name);
> + if (IS_ERR(zone))
> + continue;
> +
> + thermal_zone_device_unregister(zone);
> + kfree(zone->tzp);
> + kfree(zone->ops);
> + of_thermal_free_zone(zone->devdata);
> + }
> +}
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index f7a9f4f..fec3351 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -1371,7 +1371,7 @@ static void remove_trip_attrs(struct thermal_zone_device *tz)
> */
> struct thermal_zone_device *thermal_zone_device_register(const char *type,
> int trips, int mask, void *devdata,
> - const struct thermal_zone_device_ops *ops,
> + struct thermal_zone_device_ops *ops,
> const struct thermal_zone_params *tzp,
> int passive_delay, int polling_delay)
> {
> @@ -1751,8 +1751,14 @@ static int __init thermal_init(void)
> if (result)
> goto unregister_class;
>
> + result = of_parse_thermal_zones();
> + if (result)
> + goto exit_netlink;
> +
> return 0;
>
> +exit_netlink:
> + genetlink_exit();
> unregister_governors:
> thermal_unregister_governors();
> unregister_class:
> @@ -1768,6 +1774,7 @@ error:
>
> static void __exit thermal_exit(void)
> {
> + of_thermal_destroy_zones();
> genetlink_exit();
> class_unregister(&thermal_class);
> thermal_unregister_governors();
> diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
> index 7cf2f66..3db339f 100644
> --- a/drivers/thermal/thermal_core.h
> +++ b/drivers/thermal/thermal_core.h
> @@ -77,4 +77,13 @@ static inline int thermal_gov_user_space_register(void) { return 0; }
> static inline void thermal_gov_user_space_unregister(void) {}
> #endif /* CONFIG_THERMAL_GOV_USER_SPACE */
>
> +/* device tree support */
> +#ifdef CONFIG_THERMAL_OF
> +int of_parse_thermal_zones(void);
> +void of_thermal_destroy_zones(void);
> +#else
> +static inline int of_parse_thermal_zones(void) { return 0; }
> +static inline void of_thermal_destroy_zones(void) { }
> +#endif
> +
> #endif /* __THERMAL_CORE_H__ */
> diff --git a/include/dt-bindings/thermal/thermal.h b/include/dt-bindings/thermal/thermal.h
> new file mode 100644
> index 0000000..59c4581
> --- /dev/null
> +++ b/include/dt-bindings/thermal/thermal.h
> @@ -0,0 +1,27 @@
> +/*
> + * This header provides constants for most thermal bindings.
> + *
> + * Copyright (C) 2013 Texas Instruments
> + * Eduardo Valentin <eduardo.valentin@ti.com>
> + *
> + * GPLv2 only
> + */
> +
> +#ifndef _DT_BINDINGS_THERMAL_THERMAL_H
> +#define _DT_BINDINGS_THERMAL_THERMAL_H
> +
> +/*
> + * Here are the thermal trip types. This must
> + * match with enum thermal_trip_type at
> + * include/linux/thermal.h
> + */
> +#define THERMAL_TRIP_ACTIVE "active"
> +#define THERMAL_TRIP_PASSIVE "passive"
> +#define THERMAL_TRIP_HOT "hot"
> +#define THERMAL_TRIP_CRITICAL "critical"
I don't like this. If someone wants to include this in a C file they can't do so
at the same time as include/linux/thermal.h. The defined names are longer than
the actual string values, and the comment makes it sound like these could be
modified rather than being a fixed ABI.
I do not see the point of these constants.
Thanks,
Mark.
> +
> +/* On cooling devices upper and lower limits */
> +#define THERMAL_NO_LIMIT (-1UL)
> +
> +#endif
> +
> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
> index b268d3c..b780c5b 100644
> --- a/include/linux/thermal.h
> +++ b/include/linux/thermal.h
> @@ -143,6 +143,7 @@ struct thermal_cooling_device {
> int id;
> char type[THERMAL_NAME_LENGTH];
> struct device device;
> + struct device_node *np;
> void *devdata;
> const struct thermal_cooling_device_ops *ops;
> bool updated; /* true if the cooling device does not need update */
> @@ -172,7 +173,7 @@ struct thermal_zone_device {
> int emul_temperature;
> int passive;
> unsigned int forced_passive;
> - const struct thermal_zone_device_ops *ops;
> + struct thermal_zone_device_ops *ops;
> const struct thermal_zone_params *tzp;
> struct thermal_governor *governor;
> struct list_head thermal_instances;
> @@ -242,8 +243,31 @@ struct thermal_genl_event {
> };
>
> /* Function declarations */
> +#ifdef CONFIG_THERMAL_OF
> +struct thermal_zone_device *
> +thermal_zone_of_sensor_register(struct device *dev, int id,
> + void *data, int (*get_temp)(void *, long *),
> + int (*get_trend)(void *, long *));
> +void thermal_zone_of_sensor_unregister(struct device *dev,
> + struct thermal_zone_device *tz);
> +#else
> +static inline struct thermal_zone_device *
> +thermal_zone_of_sensor_register(struct device *dev, int id,
> + void *data, int (*get_temp)(void *, long *),
> + int (*get_trend)(void *, long *))
> +{
> + return NULL;
> +}
> +
> +static inline
> +void thermal_zone_of_sensor_unregister(struct device *dev,
> + struct thermal_zone_device *tz)
> +{
> +}
> +
> +#endif
> struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
> - void *, const struct thermal_zone_device_ops *,
> + void *, struct thermal_zone_device_ops *,
> const struct thermal_zone_params *, int, int);
> void thermal_zone_device_unregister(struct thermal_zone_device *);
>
> --
> 1.8.2.1.342.gfa7285d
>
>
^ permalink raw reply [flat|nested] 31+ messages in thread* Re: [PATCHv8 03/18] thermal: introduce device tree parser
2013-10-07 20:51 ` Mark Rutland
@ 2013-10-08 14:59 ` Eduardo Valentin
2013-11-05 18:08 ` Eduardo Valentin
1 sibling, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-10-08 14:59 UTC (permalink / raw)
To: Mark Rutland
Cc: Eduardo Valentin, swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org,
Pawel Moll, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org,
grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org,
linux-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org,
wni-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org,
linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
[-- Attachment #1: Type: text/plain, Size: 71829 bytes --]
On 07-10-2013 16:51, Mark Rutland wrote:
> Hi all,
>
> Given that this is a complex new class of binding, I'd appreciate if at least
> one other device tree maintainer could also take a look over this and voice any
> concerns or suggestions. I've left the entire patch context for this.
>
I agree with you. Did I miss someone in my To/Cc list? I got a couple of
review iterations by Stephen and Pawel (so, they are Copied) in the very
early stages of this work.
> Apologies for the munged whitespace -- my mail server appears to have helpfully
> and irreparably replaced all tabs with spaces.
I
>
> On Tue, Oct 01, 2013 at 03:39:26AM +0100, Eduardo Valentin wrote:
>> This patch introduces a device tree bindings for
>> describing the hardware thermal behavior and limits.
>> Also a parser to read and interpret the data and feed
>> it in the thermal framework is presented.
>>
>> This patch introduces a thermal data parser for device
>> tree. The parsed data is used to build thermal zones
>> and thermal binding parameters. The output data
>> can then be used to deploy thermal policies.
>>
>> This patch adds also documentation regarding this
>> API and how to define tree nodes to use
>> this infrastructure.
>>
>> Note that, in order to be able to have control
>> on the sensor registration on the DT thermal zone,
>> it was required to allow changing the thermal zone
>> .get_temp callback. For this reason, this patch
>> also removes the 'const' modifier from the .ops
>> field of thermal zone devices.
>>
>> Cc: Zhang Rui <rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>> Cc: linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>> Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>> Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
>> ---
>> Hello Mark, folks,
>>
>> So, here is v8. Pretty small changes. Most are better
>> English phrasing in the binding document. It follows changelog:
>> - Several rephrasing in the binding document, including
>> spelling, grammar and better phrasing.
>> - Removed WiP warning from binding document.
>> - Several spacing and formatting changes in the binding document
>> - Used the '-specifier' nomenclature properly in the binding doc
>> - Removed the optional property 'thermal-sensors-names', because
>> it does not provide useful runtime information
>> - Fixed description of 'polling-delay-passive'
>> - Improved examples by adding comments and better explanation
>> - s/fw/framework/g
>> - Added a WARN when sensors specifiers are greater and 1.
>>
>> All best,
>>
>> Eduardo
>>
>> ---
>> .../devicetree/bindings/thermal/thermal.txt | 587 ++++++++++++++
>> drivers/thermal/Kconfig | 13 +
>> drivers/thermal/Makefile | 1 +
>> drivers/thermal/of-thermal.c | 849 +++++++++++++++++++++
>> drivers/thermal/thermal_core.c | 9 +-
>> drivers/thermal/thermal_core.h | 9 +
>> include/dt-bindings/thermal/thermal.h | 27 +
>> include/linux/thermal.h | 28 +-
>> 8 files changed, 1520 insertions(+), 3 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
>> create mode 100644 drivers/thermal/of-thermal.c
>> create mode 100644 include/dt-bindings/thermal/thermal.h
>>
>> diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
>> new file mode 100644
>> index 0000000..ad06a8d
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/thermal/thermal.txt
>> @@ -0,0 +1,587 @@
>> +* Thermal Framework Device Tree descriptor
>> +
>> +This file describes a generic binding to provide a way of
>> +defining hardware thermal structure using device tree.
>
> s/defining/describing/
Well, I just want to avoid being prolix, and I dont really think we
loose context or meaning by using defining here.
>
>> +A thermal structure includes thermal zones and their components,
>> +such as trip points, polling intervals, sensors and cooling devices
>> +binding descriptors.
>> +
>> +The target of device tree thermal descriptors is to describe only
>> +the hardware thermal aspects. The thermal device tree bindings are
>> +not about how the system must control or which algorithm or policy
>> +must be taken in place.
>
> I'm not quite sure what this is saying -- it seems to contradict the
> design of the binding where trip points get linked to cooling device
> configuration, and thus we're defining a policy along the lines of "when
> sensor $W hits temperature $X, configure cooling device $Y with value
> $Z". I don't see how that can't be considered policy.
It is saying that describing these entities does not necessarily means
we are imposing policies, but that we are only describing the hardware
proprieties and knobs so that policies may be built on top of them.
There are plenty of algorithm to implement a control system, with
thermal is not different. We are not describing algorithms / policies,
but only focusing on hardware information and limits that we can extract
and use them to control the system.
For instance, there is no obligation to implement a closed loop
proportional-integral-derivative controller. Nor there is a strong
implication to implement a simple stepping control algorithm. But with
the hardware description flexibility we are providing with this binding,
for sure it is possible to choose one of the referred policies. We are
describing data points, so that the logic to use them can be picked out
of OS design decision.
I don't thing that matching cooling devices with trip points of sensors
on a thermal zone is defining thermal policy. This matching, to me at
least, it is a direct outcome of describing your hardware and its
limits. There are a couple of steps ahead of it to have a finalized
thermal policy.
>
> At best, we can say that policy is being defined because describing the
> physical properties of a device and dealing with this at runtime is not
> feasible.
OK. I see it slightly different, as I mentioned above. We are describing
physical properties and letting OSes to deal with them the way they choose.
>
>> +
>> +There are five types of nodes involved to describe thermal bindings:
>> +- sensors: used to describe the device source of temperature sensing;
>
> - thermal sensors: devices which may be used to take temperature
> measurements.
>
>> +- cooling devices: used to describe devices source of power dissipation control;
>
> - cooling devices: devices which may be used to dissipate heat.
>
>> +- trip points: used to describe points in temperature domain defined to
>> +make the system aware of hardware limits;
>
> - trip points: describe key temperatures at which cooling is recommended. The
> set of points should be chosen based on hardware limits.
>
>> +- cooling maps: used to describe links between trip points and cooling devices;
>> +- thermal zones: used to describe thermal data within the hardware;
>> +
>> +It follows a description of each type of these device tree nodes.
>
> How about:
>
> The following is a description of each of these node types.
OK, for the above suggestions.
>
>> +
>> +* Thermal sensor devices
>> +
>> +Thermal sensor devices are nodes providing temperature sensing capabilities on
>> +thermal zones. Typical devices are I2C ADC converters and bandgaps. These are
>> +nodes providing temperature data to thermal zones. Thermal sensor devices may
>> +control one or more internal sensors.
>> +
>> +Required property:
>> +- #thermal-sensor-cells: Used to provide sensor device specific information
>> + Type: unsigned while referring to it. Typically 0 on thermal sensor
>> + Size: one cell nodes with only one sensor, and at least 1 on nodes
>> + with several internal sensors, in order
>> + to identify uniquely the sensor instances within
>> + the IC. See thermal zone binding for more details
>> + on how consumers refer to sensor devices.
>> +
>> +* Cooling device nodes
>> +
>> +Cooling devices are nodes providing control on power dissipation. There
>> +are essentially two ways to provide control on power dissipation. First
>> +is by means of regulating device performance, which is known as passive
>> +cooling. A typical passive cooling is a CPU that has dynamic voltage and
>> +frequency scaling (DVFS), and uses lower frequencies as cooling states.
>> +Second is by means of activating devices in order to remove
>> +the dissipated heat, which is known as active cooling, e.g. regulating
>> +fan speeds. In both cases, cooling devices shall have a way to determine
>> +the state of cooling in which the device is.
>
> I'd probably say "heat dissipation" rather than "power dissipation", unless
> this is a technical term I am not aware of?
>
> Why is the determination of the state of the cooling device important?
>
>> +
>> +Required properties:
>> +- cooling-min-state: An integer indicating the smallest
>> + Type: unsigned cooling state accepted. Typically 0.
>> + Size: one cell
>> +
>> +- cooling-max-state: An integer indicating the largest
>> + Type: unsigned cooling state accepted.
>> + Size: one cell
>> +
>> +- #cooling-cells: Used to provide cooling device specific information
>> + Type: unsigned while referring to it. Must be at least 2, in order
>> + Size: one cell to specify minimum and maximum cooling state used
>> + in the reference. The first cell is the minimum
>> + cooling state requested and the second cell is
>> + the maximum cooling state requested in the reference.
>> + See Cooling device maps section below for more details
>> + on how consumers refer to cooling devices.
>
> Is it assumed that all the values between min and max are valid, or might this
> be a sparse set of cooling values?
I am assuming they are valid states.
>
>> +
>> +* Trip points
>> +
>> +The trip node is a node to describe a point in the temperature domain
>> +in which the system takes an action. This node describes just the point,
>> +not the action.
>> +
>> +Required properties:
>> +- temperature: An integer indicating the trip temperature level,
>> + Type: signed in millicelsius.
>> + Size: one cell
>> +
>> +- hysteresis: a (low) hysteresis value on 'temperature'. This is a
>> + Type: unsigned relative value, in millicelsius.
>> + Size: one cell
>
> What is it relative to?
>
> Why is 'temperature' in quotes?
They relative to the temperature property, describe above. I am
rephrasing this to avoid misunderstanding.
a (low) hysteresis value on temperature property (above).
>
>> +
>> +- type: a string containing the trip type. Supported values are:
>> + "active": A trip point to enable active cooling
>> + "passive": A trip point to enable passive cooling
>> + "hot": A trip point to notify emergency
>> + "critical": Hardware not reliable.
>> + Type: string
>> +
>> +There are also string constants defined at
>> +include/dt-bindings/thermal/thermal.h.
>
> Why?
That was originally suggested by swarren, but I was using integer
constants. I kept the his suggestion though, despite the type.
>
>> +
>> +* Cooling device maps
>> +
>> +The cooling device maps node is a node to describe how cooling devices
>> +get assigned to trip points of the zone. The cooling devices are expected
>> +to be loaded in the target system.
>> +
>> +Required properties:
>> +- cooling-device: A phandle of a cooling device with its specifier,
>> + Type: phandle of referring to which cooling device is used in this
>> + cooling device binding. In the cooling specifier, the first cell
>> + is the minimum cooling state and the second cell
>> + is the maximum cooling state used in this map.
>
> The type is wrong here -- it's a phandle + cooling-cells, not just a phandle.
I suppose you meant phandle + cooling specifier.
And yes, I am fixing that.
>
>> +- trip: A phandle of a trip point node within the same thermal
>> + Type: phandle of zone.
>> + trip point node
>> +
>> +Optional property:
>> +- contribution: The cooling contribution to the thermal zone of the
>> + Type: unsigned referred cooling device at the referred trip point.
>> + Size: one cell The contribution is a ratio of the sum
>> + of all cooling contributions within a thermal zone.
>> +
>> +Note: Using the THERMAL_NO_LIMIT (-1UL) constant in the cooling-device phandle
>> +limit specifier means:
>> +(i) - minimum state allowed for minimum cooling state used in the reference.
>> +(ii) - maximum state allowed for maximum cooling state used in the reference.
>> +Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
>> +
>> +* Thermal zone nodes
>> +
>> +The thermal zone node is the node containing all the required info
>> +for describing a thermal zone, including its cooling device bindings. The
>> +thermal zone node must contain, apart from its own properties, one sub-node
>> +containing trip nodes and one sub-node containing all the zone cooling maps.
>> +
>> +Required properties:
>> +- polling-delay: The maximum number of milliseconds to wait between polls
>> + Type: unsigned when checking this thermal zone.
>> + Size: one cell
>> +
>> +- polling-delay-passive: The maximum number of milliseconds to wait
>> + Type: unsigned between polls when performing passive cooling.
>> + Size: one cell
>> +
>> +- thermal-sensors: A list of thermal sensor phandles and sensor specifier
>> + Type: list of used while monitoring the thermal zone.
>> + sensor phandles
>
> The type is wrong here. A list of phandle + sensor specifiers.
OK.
>
>> +
>> +- trips: A sub-node which is a container of only trip point nodes
>> + Type: sub-node required to describe the thermal zone.
>> +
>> +- cooling-maps: A sub-node which is a container of only cooling device
>> + Type: sub-node map nodes, used to describe the relation between trips
>> + and cooling devices.
>> +
>> +Optional property:
>> +- coefficients: An array of integers (one signed cell) containing
>> + Type: array coefficients to compose a linear relation between
>> + Elem size: one cell the sensors listed in the thermal-sensors property.
>> + Elem type: signed Coefficients defaults to 1, in case this property
>> + is not specified. A simple linear polynomial is used:
>> + Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
>> +
>> + The coefficients are ordered and they match with sensors
>> + by means of sensor ID. Additional coefficients are
>> + interpreted as constant offset.
>> +
>> +Note: The delay properties are bound to the maximum dT/dt (temperature
>> +derivative over time) in two situations for a thermal zone:
>> +(i) - when passive cooling is activated (polling-delay-passive); and
>> +(ii) - when the zone just needs to be monitored (polling-delay) or
>> +when active cooling is activated.
>> +
>> +The maximum dT/dt is highly bound to hardware power consumption and dissipation
>> +capability. The delays should be chosen to account for said max dT/dt,
>> +such that a device does not cross several trip boundaries unexpectedly
>> +between polls. Choosing the right polling delays shall avoid having the
>> +device in temperature ranges that may damage the silicon structures and
>> +reduce silicon lifetime.
>> +
>> +* The thermal-zones node
>> +
>> +The "thermal-zones" node is a container for all thermal zone nodes. It shall
>> +contain only sub-nodes describing thermal zones as in the section
>> +"Thermal zone nodes". The "thermal-zones" node appears under "/".
>> +
>> +* Examples
>> +
>> +Below are several examples on how to use thermal data descriptors
>> +using device tree bindings:
>> +
>> +(a) - CPU thermal zone
>> +
>> +The CPU thermal zone example below describes how to setup one thermal zone
>> +using one single sensor as temperature source and many cooling devices and
>> +power dissipation control sources.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +cpus {
>> + /*
>> + * Here is an example of describing a cooling device for a DVFS
>> + * capable CPU. The CPU node describes its four OPPs.
>> + * The cooling states possible are 0..3, and they are
>> + * used as OPP indexes. The minimum cooling state is 0, which means
>> + * all four OPPs can be available to the system. The maximum
>> + * cooling state is 3, which means only the lowest OPPs (198MHz@0.85V)
>> + * can be available in the system.
>> + */
>> + cpu0: cpu@0 {
>> + ...
>> + operating-points = <
>> + /* kHz uV */
>> + 970000 1200000
>> + 792000 1100000
>> + 396000 950000
>> + 198000 850000
>> + >;
>> + cooling-min-state = <0>;
>> + cooling-max-state = <3>;
>> + #cooling-cells = <2>; /* min followed by max */
>> + };
>> + ...
>> +};
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * A simple fan controller which supports 10 speeds of operation
>> + * (represented as 0-9).
>> + */
>> + fan0: fan@0x48 {
>> + ...
>> + cooling-min-state = <0>;
>> + cooling-max-state = <9>;
>> + #cooling-cells = <2>; /* min followed by max */
>> + };
>> +};
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with a single bandgap temperature sensor.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + thermal-sensors = <&bandgap0>;
>> +
>> + trips {
>> + cpu-alert0: cpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "active";
>> + };
>> + cpu-alert1: cpu-alert {
>> + temperature = <100000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + cpu-crit: cpu-crit {
>> + temperature = <125000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + map0 {
>> + trip = <&cpu-alert0>;
>> + cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
>> + };
>> + map1 {
>> + trip = <&cpu-alert1>;
>> + cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
>> + };
>> + map2 {
>> + trip = <&cpu-alert1>;
>> + cooling-device =
>> + <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
>> + };
>> + };
>> + };
>> +};
>> +
>> +In the example above, the ADC sensor (bandgap0) at address 0x0000ED00 is
>> +used to monitor the zone 'cpu-thermal' using its sole sensor. A fan
>> +device (fan0) is controlled via I2C bus 1, at address 0x48, and has ten
>> +different cooling states 0-9. It is used to remove the heat out of
>> +the thermal zone 'cpu-thermal' using its cooling states
>> +from its minimum to 4, when it reaches trip point 'cpu-alert0'
>> +at 90C, as an example of active cooling. The same cooling device is used at
>> +'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
>> +linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
>> +using all its cooling states at trip point 'cpu-alert1',
>> +which is a trip point at 100C. On the thermal zone 'cpu-thermal', at the
>> +temperature of 125C, represented by the trip point 'cpu-crit', the silicon
>> +is not reliable anymore.
>> +
>> +(b) - IC with several internal sensors
>> +
>> +The example below describes how to deploy several thermal zones based off a
>> +single sensor IC, assuming it has several internal sensors. This is a common
>> +case on SoC designs with several internal IPs that may need different thermal
>> +requirements, and thus may have their own sensor to monitor or detect internal
>> +hotspots in their silicon.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with several bandgap temperature sensors.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <1>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 0>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + cpu-alert: cpu-alert {
>> + temperature = <100000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + cpu-crit: cpu-crit {
>> + temperature = <125000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +
>> + gpu-thermal: gpu-thermal {
>> + polling-delay-passive = <120>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 1>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + gpu-alert: gpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + gpu-crit: gpu-crit {
>> + temperature = <105000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +
>> + dsp-thermal: dsp-thermal {
>> + polling-delay-passive = <50>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 2>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + dsp-alert: gpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + dsp-crit: gpu-crit {
>> + temperature = <135000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +};
>> +
>> +In the example above, there is one bandgap IC which has the capability to
>> +monitor three sensors. The hardware has been designed so that sensors are
>> +placed on different places in the DIE to monitor different temperature
>> +hotspots: one for CPU thermal zone, one for GPU thermal zone and the
>> +other to monitor a DSP thermal zone.
>> +
>> +Thus, there is a need to assign each sensor provided by the bandgap IC
>> +to different thermal zones. This is achieved by means of using the
>> +#thermal-sensor-cells property and using the first cell of the sensor
>> +specifier as sensor ID. In the example, then, <bandgap 0> is used to
>> +monitor CPU thermal zone, <bandgap 1> is used to monitor GPU thermal
>> +zone and <bandgap 2> is used to monitor DSP thermal zone. Each zone
>> +may be uncorrelated, having its own dT/dt requirements, trips
>> +and cooling maps.
>> +
>> +
>> +(c) - Several sensors within one single thermal zone
>> +
>> +The example below illustrates how to use more than one sensor within
>> +one thermal zone.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * A simple IC with a single temperature sensor.
>> + */
>> + adc: sensor@0x49 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with a single bandgap temperature sensor.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + thermal-sensors = <&bandgap0>, /* cpu */
>> + <&adc>; /* pcb north */
>> +
>> + /* hotspot = 100 * bandgap - 120 * adc + 484 */
>> + coefficients = <100 -120 484>;
>> +
>> + trips {
>> + ...
>> + };
>> +
>> + cooling-maps {
>> + ...
>> + };
>> + };
>> +};
>> +
>> +In some cases, there is a need to use more than one sensor to extrapolate
>> +a thermal hotspot in the silicon. The above example illustrates this situation.
>> +For instance, it may be the case that a sensor external to CPU IP may be placed
>> +close to CPU hotspot and together with internal CPU sensor, it is used
>> +to determine the hotspot. Assuming this is the case for the above example,
>> +the hypothetical extrapolation rule would be:
>> + hotspot = 100 * bandgap - 120 * adc + 484
>> +
>> +In other context, the same idea can be used to add fixed offset. For instance,
>> +consider the hotspot extrapolation rule below:
>> + hotspot = 1 * adc + 6000
>> +
>> +In the above equation, the hotspot is always 6C higher than what is read
>> +from the ADC sensor. The binding would be then:
>> + thermal-sensors = <&adc>;
>> +
>> + /* hotspot = 1 * adc + 6000 */
>> + coefficients = <1 6000>;
>> +
>> +(d) - Board thermal
>> +
>> +The board thermal example below illustrates how to setup one thermal zone
>> +with many sensors and many cooling devices.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * An IC with several temperature sensor.
>> + */
>> + adc-dummy: sensor@0x50 {
>> + ...
>> + #thermal-sensor-cells = <1>; /* sensor internal ID */
>> + };
>> +};
>> +
>> +thermal-zones {
>> + batt-thermal {
>> + polling-delay-passive = <500>; /* milliseconds */
>> + polling-delay = <2500>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&adc-dummy 4>;
>> +
>> + trips {
>> + ...
>> + };
>> +
>> + cooling-maps {
>> + ...
>> + };
>> + };
>> +
>> + board-thermal: board-thermal {
>> + polling-delay-passive = <1000>; /* milliseconds */
>> + polling-delay = <2500>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&adc-dummy 0>, /* pcb top edge */
>> + <&adc-dummy 1>, /* lcd */
>> + <&adc-dymmy 2>; /* back cover */
>> + /*
>> + * An array of coefficients describing the sensor
>> + * linear relation. E.g.:
>> + * z = c1*x1 + c2*x2 + c3*x3
>> + */
>> + coefficients = <1200 -345 890>;
>> +
>> + trips {
>> + /* Trips are based on resulting linear equation */
>> + cpu-trip: cpu-trip {
>> + temperature = <60000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + gpu-trip: gpu-trip {
>> + temperature = <55000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + }
>> + lcd-trip: lcp-trip {
>> + temperature = <53000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + crit-trip: crit-trip {
>> + temperature = <68000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + map0 {
>> + trip = <&cpu-trip>;
>> + cooling-device = <&cpu0 0 2>;
>> + contribution = <55>;
>> + };
>> + map1 {
>> + trip = <&gpu-trip>;
>> + cooling-device = <&gpu0 0 2>;
>> + contribution = <20>;
>> + };
>> + map2 {
>> + trip = <&lcd-trip>;
>> + cooling-device = <&lcd0 5 10>;
>> + contribution = <15>;
>> + };
>> + };
>> + };
>> +};
>> +
>> +The above example is a mix of previous examples, a sensor IP with several internal
>> +sensors used to monitor different zones, one of them is composed by several sensors and
>> +with different cooling devices.
>> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
>> index dbfc390..dd81eb8 100644
>> --- a/drivers/thermal/Kconfig
>> +++ b/drivers/thermal/Kconfig
>> @@ -29,6 +29,19 @@ config THERMAL_HWMON
>> Say 'Y' here if you want all thermal sensors to
>> have hwmon sysfs interface too.
>>
>> +config THERMAL_OF
>> + bool
>> + prompt "APIs to parse thermal data out of device tree"
>> + depends on OF
>> + default y
>> + help
>> + This options provides helpers to add the support to
>> + read and parse thermal data definitions out of the
>> + device tree blob.
>> +
>> + Say 'Y' here if you need to build thermal infrastructure
>> + based on device tree.
>> +
>> choice
>> prompt "Default Thermal governor"
>> default THERMAL_DEFAULT_GOV_STEP_WISE
>> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
>> index 584b363..4b03956 100644
>> --- a/drivers/thermal/Makefile
>> +++ b/drivers/thermal/Makefile
>> @@ -7,6 +7,7 @@ thermal_sys-y += thermal_core.o
>>
>> # interface to/from other layers providing sensors
>> thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
>> +thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
>>
>> # governors
>> thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
>> diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
>> new file mode 100644
>> index 0000000..66f9eb2
>> --- /dev/null
>> +++ b/drivers/thermal/of-thermal.c
>> @@ -0,0 +1,849 @@
>> +/*
>> + * of-thermal.c - Generic Thermal Management device tree support.
>> + *
>> + * Copyright (C) 2013 Texas Instruments
>> + * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
>> + *
>> + *
>> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; version 2 of the License.
>> + *
>> + * This program is distributed in the hope that it will be useful, but
>> + * WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> + * General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along
>> + * with this program; if not, write to the Free Software Foundation, Inc.,
>> + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
>> + *
>> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> + */
>> +#include <linux/thermal.h>
>> +#include <linux/slab.h>
>> +#include <linux/types.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/err.h>
>> +#include <linux/export.h>
>> +#include <linux/string.h>
>> +
>> +#include "thermal_core.h"
>> +
>> +/*** Private data structures to represent thermal device tree data ***/
>> +
>> +/**
>> + * struct __thermal_trip - representation of a point in temperature domain
>> + * @np: pointer to struct device_node that this trip point was created from
>> + * @temperature: temperature value in miliCelsius
>> + * @hysteresis: relative hysteresis in miliCelsius
>> + * @type: trip point type
>> + */
>> +
>> +struct __thermal_trip {
>> + struct device_node *np;
>> + unsigned long int temperature;
>> + unsigned long int hysteresis;
>> + enum thermal_trip_type type;
>> +};
>> +
>> +/**
>> + * struct __thermal_bind_param - a match between trip and cooling device
>> + * @cooling_device: a pointer to identify the referred cooling device
>> + * @trip_id: the trip point index
>> + * @usage: the percentage (from 0 to 100) of cooling contribution
>> + * @min: minimum cooling state used at this trip point
>> + * @max: maximum cooling state used at this trip point
>> + */
>> +
>> +struct __thermal_bind_params {
>> + struct device_node *cooling_device;
>> + unsigned int trip_id;
>> + unsigned int usage;
>> + unsigned long min;
>> + unsigned long max;
>> +};
>> +
>> +/**
>> + * struct __thermal_zone - internal representation of a thermal zone
>> + * @mode: current thermal zone device mode (enabled/disabled)
>> + * @passive_delay: polling interval while passive cooling is activated
>> + * @polling_delay: zone polling interval
>> + * @ntrips: number of trip points
>> + * @trips: an array of trip points (0..ntrips - 1)
>> + * @num_tbps: number of thermal bind params
>> + * @tbps: an array of thermal bind params (0..num_tbps - 1)
>> + * @sensor_data: sensor private data used while reading temperature and trend
>> + * @get_temp: sensor callback to read temperature
>> + * @get_trend: sensor callback to read temperature trend
>> + */
>> +
>> +struct __thermal_zone {
>> + enum thermal_device_mode mode;
>> + int passive_delay;
>> + int polling_delay;
>> +
>> + /* trip data */
>> + int ntrips;
>> + struct __thermal_trip *trips;
>> +
>> + /* cooling binding data */
>> + int num_tbps;
>> + struct __thermal_bind_params *tbps;
>> +
>> + /* sensor interface */
>> + void *sensor_data;
>> + int (*get_temp)(void *, long *);
>> + int (*get_trend)(void *, long *);
>> +};
>> +
>> +/*** DT thermal zone device callbacks ***/
>> +
>> +static int of_thermal_get_temp(struct thermal_zone_device *tz,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (!data->get_temp)
>> + return -EINVAL;
>> +
>> + return data->get_temp(data->sensor_data, temp);
>> +}
>> +
>> +static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
>> + enum thermal_trend *trend)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> + long dev_trend;
>> + int r;
>> +
>> + if (!data->get_trend)
>> + return -EINVAL;
>> +
>> + r = data->get_trend(data->sensor_data, &dev_trend);
>> + if (r)
>> + return r;
>> +
>> + /* TODO: These intervals might have some thresholds, but in core code */
>> + if (dev_trend > 0)
>> + *trend = THERMAL_TREND_RAISING;
>> + else if (dev_trend < 0)
>> + *trend = THERMAL_TREND_DROPPING;
>> + else
>> + *trend = THERMAL_TREND_STABLE;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_bind(struct thermal_zone_device *thermal,
>> + struct thermal_cooling_device *cdev)
>> +{
>> + struct __thermal_zone *data = thermal->devdata;
>> + int i;
>> +
>> + if (!data || IS_ERR(data))
>> + return -ENODEV;
>> +
>> + /* find where to bind */
>> + for (i = 0; i < data->num_tbps; i++) {
>> + struct __thermal_bind_params *tbp = data->tbps + i;
>> +
>> + if (tbp->cooling_device == cdev->np) {
>> + int ret;
>> +
>> + ret = thermal_zone_bind_cooling_device(thermal,
>> + tbp->trip_id, cdev,
>> + tbp->min,
>> + tbp->max);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_unbind(struct thermal_zone_device *thermal,
>> + struct thermal_cooling_device *cdev)
>> +{
>> + struct __thermal_zone *data = thermal->devdata;
>> + int i;
>> +
>> + if (!data || IS_ERR(data))
>> + return -ENODEV;
>> +
>> + /* find where to unbind */
>> + for (i = 0; i < data->num_tbps; i++) {
>> + struct __thermal_bind_params *tbp = data->tbps + i;
>> +
>> + if (tbp->cooling_device == cdev->np) {
>> + int ret;
>> +
>> + ret = thermal_zone_unbind_cooling_device(thermal,
>> + tbp->trip_id, cdev);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_mode(struct thermal_zone_device *tz,
>> + enum thermal_device_mode *mode)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + *mode = data->mode;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_mode(struct thermal_zone_device *tz,
>> + enum thermal_device_mode mode)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + mutex_lock(&tz->lock);
>> +
>> + if (mode == THERMAL_DEVICE_ENABLED)
>> + tz->polling_delay = data->polling_delay;
>> + else
>> + tz->polling_delay = 0;
>> +
>> + mutex_unlock(&tz->lock);
>> +
>> + data->mode = mode;
>> + thermal_zone_device_update(tz);
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
>> + enum thermal_trip_type *type)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *type = data->trips[trip].type;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *temp = data->trips[trip].temperature;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
>> + unsigned long temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + /* thermal framework should take care of data->mask & (1 << trip) */
>> + data->trips[trip].temperature = temp;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
>> + unsigned long *hyst)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *hyst = data->trips[trip].hysteresis;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
>> + unsigned long hyst)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + /* thermal framework should take care of data->mask & (1 << trip) */
>> + data->trips[trip].hysteresis = hyst;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> + int i;
>> +
>> + for (i = 0; i < data->ntrips; i++)
>> + if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
>> + *temp = data->trips[i].temperature;
>> + return 0;
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static struct thermal_zone_device_ops of_thermal_ops = {
>> + .get_mode = of_thermal_get_mode,
>> + .set_mode = of_thermal_set_mode,
>> +
>> + .get_trip_type = of_thermal_get_trip_type,
>> + .get_trip_temp = of_thermal_get_trip_temp,
>> + .set_trip_temp = of_thermal_set_trip_temp,
>> + .get_trip_hyst = of_thermal_get_trip_hyst,
>> + .set_trip_hyst = of_thermal_set_trip_hyst,
>> + .get_crit_temp = of_thermal_get_crit_temp,
>> +
>> + .bind = of_thermal_bind,
>> + .unbind = of_thermal_unbind,
>> +};
>> +
>> +/*** sensor API ***/
>> +
>> +static struct thermal_zone_device *
>> +thermal_zone_of_add_sensor(struct device_node *zone,
>> + struct device_node *sensor, void *data,
>> + int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + struct thermal_zone_device *tzd;
>> + struct __thermal_zone *tz;
>> +
>> + tzd = thermal_zone_get_zone_by_name(zone->name);
>> + if (IS_ERR(tzd))
>> + return ERR_PTR(-EPROBE_DEFER);
>> +
>> + tz = tzd->devdata;
>> +
>> + mutex_lock(&tzd->lock);
>> + tz->get_temp = get_temp;
>> + tz->get_trend = get_trend;
>> + tz->sensor_data = data;
>> +
>> + tzd->ops->get_temp = of_thermal_get_temp;
>> + tzd->ops->get_trend = of_thermal_get_trend;
>> + mutex_unlock(&tzd->lock);
>> +
>> + return tzd;
>> +}
>> +
>> +/**
>> + * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
>> + * @dev: a valid struct device pointer of a sensor device. Must contain
>> + * a valid .of_node, for the sensor node.
>> + * @sensor_id: a sensor identifier, in case the sensor IP has more
>> + * than one sensors
>> + * @data: a private pointer (owned by the caller) that will be passed
>> + * back, when a temperature reading is needed.
>> + * @get_temp: a pointer to a function that reads the sensor temperature.
>> + * @get_trend: a pointer to a function that reads the sensor temperature trend.
>> + *
>> + * This function will search the list of thermal zones described in device
>> + * tree and look for the zone that refer to the sensor device pointed by
>> + * @dev->of_node as temperature providers. For the zone pointing to the
>> + * sensor node, the sensor will be added to the DT thermal zone device.
>> + *
>> + * The thermal zone temperature is provided by the @get_temp function
>> + * pointer. When called, it will have the private pointer @data back.
>> + *
>> + * The thermal zone temperature trend is provided by the @get_trend function
>> + * pointer. When called, it will have the private pointer @data back.
>> + *
>> + * TODO:
>> + * 01 - This function must enqueue the new sensor instead of using
>> + * it as the only source of temperature values.
>> + *
>> + * 02 - There must be a way to match the sensor with all thermal zones
>> + * that refer to it.
>> + *
>> + * Return: On success returns a valid struct thermal_zone_device,
>> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
>> + * check the return value with help of IS_ERR() helper.
>> + */
>> +struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + struct device_node *np, *child, *sensor_np;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np)
>> + return ERR_PTR(-ENODEV);
>> +
>> + if (!dev || !dev->of_node)
>> + return ERR_PTR(-EINVAL);
>> +
>> + sensor_np = dev->of_node;
>> +
>> + for_each_child_of_node(np, child) {
>> + struct of_phandle_args sensor_specs;
>> + int ret, id;
>> +
>> + /* For now, thermal framework supports only 1 sensor per zone */
>> + ret = of_parse_phandle_with_args(child, "thermal-sensors",
>> + "#thermal-sensor-cells",
>> + 0, &sensor_specs);
>> + if (ret)
>> + continue;
>> +
>> + if (sensor_specs.args_count >= 1) {
>> + id = sensor_specs.args[0];
>> + WARN(sensor_specs.args_count > 1,
>> + "%s: too many cells in sensor specifier %d\n",
>> + sensor_specs.np->name, sensor_specs.args_count);
>> + } else {
>> + id = 0;
>> + }
>> +
>> + if (sensor_specs.np == sensor_np && id == sensor_id) {
>> + of_node_put(np);
>> + return thermal_zone_of_add_sensor(child, sensor_np,
>> + data,
>> + get_temp,
>> + get_trend);
>> + }
>> + }
>> + of_node_put(np);
>> +
>> + return ERR_PTR(-ENODEV);
>> +}
>> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
>> +
>> +/**
>> + * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
>> + * @dev: a valid struct device pointer of a sensor device. Must contain
>> + * a valid .of_node, for the sensor node.
>> + * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
>> + *
>> + * This function removes the sensor callbacks and private data from the
>> + * thermal zone device registered with thermal_zone_of_sensor_register()
>> + * API. It will also silent the zone by remove the .get_temp() and .get_trend()
>> + * thermal zone device callbacks.
>> + *
>> + * TODO: When the support to several sensors per zone is added, this
>> + * function must search the sensor list based on @dev parameter.
>> + *
>> + */
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tzd)
>> +{
>> + struct __thermal_zone *tz;
>> +
>> + if (!dev || !tzd || !tzd->devdata)
>> + return;
>> +
>> + tz = tzd->devdata;
>> +
>> + /* no __thermal_zone, nothing to be done */
>> + if (!tz)
>> + return;
>> +
>> + mutex_lock(&tzd->lock);
>> + tzd->ops->get_temp = NULL;
>> + tzd->ops->get_trend = NULL;
>> +
>> + tz->get_temp = NULL;
>> + tz->get_trend = NULL;
>> + tz->sensor_data = NULL;
>> + mutex_unlock(&tzd->lock);
>> +}
>> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
>> +
>> +/*** functions parsing device tree nodes ***/
>> +
>> +/**
>> + * thermal_of_populate_bind_params - parse and fill cooling map data
>> + * @np: DT node containing a cooling-map node
>> + * @__tbp: data structure to be filled with cooling map info
>> + * @trips: array of thermal zone trip points
>> + * @ntrips: number of trip points inside trips.
>> + *
>> + * This function parses a cooling-map type of node represented by
>> + * @np parameter and fills the read data into @__tbp data structure.
>> + * It needs the already parsed array of trip points of the thermal zone
>> + * in consideration.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + */
>> +static int thermal_of_populate_bind_params(struct device_node *np,
>> + struct __thermal_bind_params *__tbp,
>> + struct __thermal_trip *trips,
>> + int ntrips)
>> +{
>> + struct of_phandle_args cooling_spec;
>> + struct device_node *trip;
>> + int ret, i;
>> + u32 prop;
>> +
>> + /* Default weight. Usage is optional */
>> + __tbp->usage = 0;
>> + ret = of_property_read_u32(np, "contribution", &prop);
>> + if (ret == 0)
>> + __tbp->usage = prop;
>> +
>> + trip = of_parse_phandle(np, "trip", 0);
>> + if (!trip) {
>> + pr_err("missing trip property\n");
>> + return -ENODEV;
>> + }
>> +
>> + /* match using device_node */
>> + for (i = 0; i < ntrips; i++)
>> + if (trip == trips[i].np) {
>> + __tbp->trip_id = i;
>> + break;
>> + }
>> +
>> + if (i == ntrips) {
>> + ret = -ENODEV;
>> + goto end;
>> + }
>> +
>> + ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
>> + 0, &cooling_spec);
>> + if (ret < 0) {
>> + pr_err("missing cooling_device property\n");
>> + goto end;
>> + }
>> + __tbp->cooling_device = cooling_spec.np;
>> + if (cooling_spec.args_count >= 2) { /* at least min and max */
>> + __tbp->min = cooling_spec.args[0];
>> + __tbp->max = cooling_spec.args[1];
>> + } else {
>> + pr_err("wrong reference to cooling device, missing limits\n");
>> + }
>> +
>> +end:
>> + of_node_put(trip);
>> +
>> + return ret;
>> +}
>> +
>> +/**
>> + * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
>> + * into the device tree binding of 'trip', property type.
>> + */
>> +static const char * const trip_types[] = {
>> + [THERMAL_TRIP_ACTIVE] = "active",
>> + [THERMAL_TRIP_PASSIVE] = "passive",
>> + [THERMAL_TRIP_HOT] = "hot",
>> + [THERMAL_TRIP_CRITICAL] = "critical",
>> +};
>> +
>> +/**
>> + * thermal_of_get_trip_type - Get phy mode for given device_node
>> + * @np: Pointer to the given device_node
>> + * @type: Pointer to resulting trip type
>> + *
>> + * The function gets trip type string from property 'type',
>> + * and store its index in trip_types table in @type,
>> + *
>> + * Return: 0 on success, or errno in error case.
>> + */
>> +static int thermal_of_get_trip_type(struct device_node *np,
>> + enum thermal_trip_type *type)
>> +{
>> + const char *t;
>> + int err, i;
>> +
>> + err = of_property_read_string(np, "type", &t);
>> + if (err < 0)
>> + return err;
>> +
>> + for (i = 0; i < ARRAY_SIZE(trip_types); i++)
>> + if (!strcasecmp(t, trip_types[i])) {
>> + *type = i;
>> + return 0;
>> + }
>> +
>> + return -ENODEV;
>> +}
>> +
>> +/**
>> + * thermal_of_populate_trip - parse and fill one trip point data
>> + * @np: DT node containing a trip point node
>> + * @trip: trip point data structure to be filled up
>> + *
>> + * This function parses a trip point type of node represented by
>> + * @np parameter and fills the read data into @trip data structure.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + */
>> +static int thermal_of_populate_trip(struct device_node *np,
>> + struct __thermal_trip *trip)
>> +{
>> + int prop;
>> + int ret;
>> +
>> + ret = of_property_read_u32(np, "temperature", &prop);
>> + if (ret < 0) {
>> + pr_err("missing temperature property\n");
>> + return ret;
>> + }
>> + trip->temperature = prop;
>> +
>> + ret = of_property_read_u32(np, "hysteresis", &prop);
>> + if (ret < 0) {
>> + pr_err("missing hysteresis property\n");
>> + return ret;
>> + }
>> + trip->hysteresis = prop;
>> +
>> + ret = thermal_of_get_trip_type(np, &trip->type);
>> + if (ret < 0) {
>> + pr_err("wrong trip type property\n");
>> + return ret;
>> + }
>> +
>> + /* Required for cooling map matching */
>> + trip->np = np;
>> +
>> + return 0;
>> +}
>> +
>> +/**
>> + * thermal_of_build_thermal_zone - parse and fill one thermal zone data
>> + * @np: DT node containing a thermal zone node
>> + *
>> + * This function parses a thermal zone type of node represented by
>> + * @np parameter and fills the read data into a __thermal_zone data structure
>> + * and return this pointer.
>> + *
>> + * TODO: Missing properties to parse: thermal-sensor-names and coefficients
>> + *
>> + * Return: On success returns a valid struct __thermal_zone,
>> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
>> + * check the return value with help of IS_ERR() helper.
>> + */
>> +static struct __thermal_zone *
>> +thermal_of_build_thermal_zone(struct device_node *np)
>> +{
>> + struct device_node *child = NULL, *gchild;
>> + struct __thermal_zone *tz;
>> + int ret, i;
>> + u32 prop;
>> +
>> + if (!np) {
>> + pr_err("no thermal zone np\n");
>> + return ERR_PTR(-EINVAL);
>> + }
>> +
>> + tz = kzalloc(sizeof(*tz), GFP_KERNEL);
>> + if (!tz)
>> + return ERR_PTR(-ENOMEM);
>> +
>> + ret = of_property_read_u32(np, "polling-delay-passive", &prop);
>> + if (ret < 0) {
>> + pr_err("missing polling-delay-passive property\n");
>> + goto free_tz;
>> + }
>> + tz->passive_delay = prop;
>> +
>> + ret = of_property_read_u32(np, "polling-delay", &prop);
>> + if (ret < 0) {
>> + pr_err("missing polling-delay property\n");
>> + goto free_tz;
>> + }
>> + tz->polling_delay = prop;
>> +
>> + /* trips */
>> + child = of_get_child_by_name(np, "trips");
>> +
>> + /* No trips provided */
>> + if (!child)
>> + goto finish;
>> +
>> + tz->ntrips = of_get_child_count(child);
>> + if (tz->ntrips == 0) /* must have at least one child */
>> + goto finish;
>> +
>> + tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
>> + if (!tz->trips) {
>> + ret = -ENOMEM;
>> + goto free_tz;
>> + }
>> +
>> + i = 0;
>> + for_each_child_of_node(child, gchild) {
>> + ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
>> + if (ret)
>> + goto free_trips;
>> + }
>> +
>> + of_node_put(child);
>> +
>> + /* cooling-maps */
>> + child = of_get_child_by_name(np, "cooling-maps");
>> +
>> + /* cooling-maps not provided */
>> + if (!child)
>> + goto finish;
>> +
>> + tz->num_tbps = of_get_child_count(child);
>> + if (tz->num_tbps == 0)
>> + goto finish;
>> +
>> + tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
>> + if (!tz->tbps) {
>> + ret = -ENOMEM;
>> + goto free_trips;
>> + }
>> +
>> + i = 0;
>> + for_each_child_of_node(child, gchild)
>> + ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
>> + tz->trips, tz->ntrips);
>> + if (ret)
>> + goto free_tbps;
>> +
>> +finish:
>> + of_node_put(child);
>> + tz->mode = THERMAL_DEVICE_DISABLED;
>> +
>> + return tz;
>> +
>> +free_tbps:
>> + kfree(tz->tbps);
>> +free_trips:
>> + kfree(tz->trips);
>> +free_tz:
>> + kfree(tz);
>> + of_node_put(child);
>> +
>> + return ERR_PTR(ret);
>> +}
>> +
>> +static inline void of_thermal_free_zone(struct __thermal_zone *tz)
>> +{
>> + kfree(tz->tbps);
>> + kfree(tz->trips);
>> + kfree(tz);
>> +}
>> +
>> +/**
>> + * of_parse_thermal_zones - parse device tree thermal data
>> + *
>> + * Initialization function that can be called by machine initialization
>> + * code to parse thermal data and populate the thermal framework
>> + * with hardware thermal zones info. This function only parses thermal zones.
>> + * Cooling devices and sensor devices nodes are supposed to be parsed
>> + * by their respective drivers.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + *
>> + */
>> +int __init of_parse_thermal_zones(void)
>> +{
>> + struct device_node *np, *child;
>> + struct __thermal_zone *tz;
>> + struct thermal_zone_device_ops *ops;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np) {
>> + pr_debug("unable to find thermal zones\n");
>> + return 0; /* Run successfully on systems without thermal DT */
>> + }
>> +
>> + for_each_child_of_node(np, child) {
>> + struct thermal_zone_device *zone;
>> + struct thermal_zone_params *tzp;
>> +
>> + tz = thermal_of_build_thermal_zone(child);
>> + if (IS_ERR(tz)) {
>> + pr_err("failed to build thermal zone %s: %ld\n",
>> + child->name,
>> + PTR_ERR(tz));
>> + continue;
>> + }
>> +
>> + ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
>> + if (!ops)
>> + goto exit_free;
>> +
>> + tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
>> + if (!tzp) {
>> + kfree(ops);
>> + goto exit_free;
>> + }
>> +
>> + /* No hwmon because there might be hwmon drivers registering */
>> + tzp->no_hwmon = true;
>> +
>> + zone = thermal_zone_device_register(child->name, tz->ntrips,
>> + 0, tz,
>> + ops, tzp,
>> + tz->passive_delay,
>> + tz->polling_delay);
>> + if (IS_ERR(zone)) {
>> + pr_err("Failed to build %s zone %ld\n", child->name,
>> + PTR_ERR(zone));
>> + kfree(tzp);
>> + kfree(ops);
>> + of_thermal_free_zone(tz);
>> + /* attempting to build remaining zones still */
>> + }
>> + }
>> +
>> + return 0;
>> +
>> +exit_free:
>> + of_thermal_free_zone(tz);
>> +
>> + /* no memory available, so free what we have built */
>> + of_thermal_destroy_zones();
>> +
>> + return -ENOMEM;
>> +}
>> +
>> +/**
>> + * of_thermal_destroy_zones - remove all zones parsed and allocated resources
>> + *
>> + * Finds all zones parsed and added to the thermal framework and remove them
>> + * from the system, together with their resources.
>> + *
>> + */
>> +void __exit of_thermal_destroy_zones(void)
>> +{
>> + struct device_node *np, *child;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np) {
>> + pr_err("unable to find thermal zones\n");
>> + return;
>> + }
>> +
>> + for_each_child_of_node(np, child) {
>> + struct thermal_zone_device *zone;
>> +
>> + zone = thermal_zone_get_zone_by_name(child->name);
>> + if (IS_ERR(zone))
>> + continue;
>> +
>> + thermal_zone_device_unregister(zone);
>> + kfree(zone->tzp);
>> + kfree(zone->ops);
>> + of_thermal_free_zone(zone->devdata);
>> + }
>> +}
>> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
>> index f7a9f4f..fec3351 100644
>> --- a/drivers/thermal/thermal_core.c
>> +++ b/drivers/thermal/thermal_core.c
>> @@ -1371,7 +1371,7 @@ static void remove_trip_attrs(struct thermal_zone_device *tz)
>> */
>> struct thermal_zone_device *thermal_zone_device_register(const char *type,
>> int trips, int mask, void *devdata,
>> - const struct thermal_zone_device_ops *ops,
>> + struct thermal_zone_device_ops *ops,
>> const struct thermal_zone_params *tzp,
>> int passive_delay, int polling_delay)
>> {
>> @@ -1751,8 +1751,14 @@ static int __init thermal_init(void)
>> if (result)
>> goto unregister_class;
>>
>> + result = of_parse_thermal_zones();
>> + if (result)
>> + goto exit_netlink;
>> +
>> return 0;
>>
>> +exit_netlink:
>> + genetlink_exit();
>> unregister_governors:
>> thermal_unregister_governors();
>> unregister_class:
>> @@ -1768,6 +1774,7 @@ error:
>>
>> static void __exit thermal_exit(void)
>> {
>> + of_thermal_destroy_zones();
>> genetlink_exit();
>> class_unregister(&thermal_class);
>> thermal_unregister_governors();
>> diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
>> index 7cf2f66..3db339f 100644
>> --- a/drivers/thermal/thermal_core.h
>> +++ b/drivers/thermal/thermal_core.h
>> @@ -77,4 +77,13 @@ static inline int thermal_gov_user_space_register(void) { return 0; }
>> static inline void thermal_gov_user_space_unregister(void) {}
>> #endif /* CONFIG_THERMAL_GOV_USER_SPACE */
>>
>> +/* device tree support */
>> +#ifdef CONFIG_THERMAL_OF
>> +int of_parse_thermal_zones(void);
>> +void of_thermal_destroy_zones(void);
>> +#else
>> +static inline int of_parse_thermal_zones(void) { return 0; }
>> +static inline void of_thermal_destroy_zones(void) { }
>> +#endif
>> +
>> #endif /* __THERMAL_CORE_H__ */
>> diff --git a/include/dt-bindings/thermal/thermal.h b/include/dt-bindings/thermal/thermal.h
>> new file mode 100644
>> index 0000000..59c4581
>> --- /dev/null
>> +++ b/include/dt-bindings/thermal/thermal.h
>> @@ -0,0 +1,27 @@
>> +/*
>> + * This header provides constants for most thermal bindings.
>> + *
>> + * Copyright (C) 2013 Texas Instruments
>> + * Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
>> + *
>> + * GPLv2 only
>> + */
>> +
>> +#ifndef _DT_BINDINGS_THERMAL_THERMAL_H
>> +#define _DT_BINDINGS_THERMAL_THERMAL_H
>> +
>> +/*
>> + * Here are the thermal trip types. This must
>> + * match with enum thermal_trip_type at
>> + * include/linux/thermal.h
>> + */
>> +#define THERMAL_TRIP_ACTIVE "active"
>> +#define THERMAL_TRIP_PASSIVE "passive"
>> +#define THERMAL_TRIP_HOT "hot"
>> +#define THERMAL_TRIP_CRITICAL "critical"
>
> I don't like this. If someone wants to include this in a C file they can't do so
> at the same time as include/linux/thermal.h. The defined names are longer than
> the actual string values, and the comment makes it sound like these could be
> modified rather than being a fixed ABI.
>
> I do not see the point of these constants.
>
> Thanks,
> Mark.
>
>> +
>> +/* On cooling devices upper and lower limits */
>> +#define THERMAL_NO_LIMIT (-1UL)
>> +
>> +#endif
>> +
>> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
>> index b268d3c..b780c5b 100644
>> --- a/include/linux/thermal.h
>> +++ b/include/linux/thermal.h
>> @@ -143,6 +143,7 @@ struct thermal_cooling_device {
>> int id;
>> char type[THERMAL_NAME_LENGTH];
>> struct device device;
>> + struct device_node *np;
>> void *devdata;
>> const struct thermal_cooling_device_ops *ops;
>> bool updated; /* true if the cooling device does not need update */
>> @@ -172,7 +173,7 @@ struct thermal_zone_device {
>> int emul_temperature;
>> int passive;
>> unsigned int forced_passive;
>> - const struct thermal_zone_device_ops *ops;
>> + struct thermal_zone_device_ops *ops;
>> const struct thermal_zone_params *tzp;
>> struct thermal_governor *governor;
>> struct list_head thermal_instances;
>> @@ -242,8 +243,31 @@ struct thermal_genl_event {
>> };
>>
>> /* Function declarations */
>> +#ifdef CONFIG_THERMAL_OF
>> +struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *));
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tz);
>> +#else
>> +static inline struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + return NULL;
>> +}
>> +
>> +static inline
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tz)
>> +{
>> +}
>> +
>> +#endif
>> struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
>> - void *, const struct thermal_zone_device_ops *,
>> + void *, struct thermal_zone_device_ops *,
>> const struct thermal_zone_params *, int, int);
>> void thermal_zone_device_unregister(struct thermal_zone_device *);
>>
>> --
>> 1.8.2.1.342.gfa7285d
>>
>>
>
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
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^ permalink raw reply [flat|nested] 31+ messages in thread* Re: [PATCHv8 03/18] thermal: introduce device tree parser
2013-10-07 20:51 ` Mark Rutland
2013-10-08 14:59 ` Eduardo Valentin
@ 2013-11-05 18:08 ` Eduardo Valentin
1 sibling, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-11-05 18:08 UTC (permalink / raw)
To: Mark Rutland
Cc: Eduardo Valentin, swarren@wwwdotorg.org, Pawel Moll,
ian.campbell@citrix.com, rob.herring@calxeda.com,
grant.likely@linaro.org, linux@roeck-us.net, rui.zhang@intel.com,
wni@nvidia.com, durgadoss.r@intel.com, linux-pm@vger.kernel.org,
devicetree@vger.kernel.org, lm-sensors@lm-sensors.org,
linux-kernel@vger.kernel.org
[-- Attachment #1: Type: text/plain, Size: 69857 bytes --]
Hello device tree maintainers,
On 07-10-2013 16:51, Mark Rutland wrote:
> Hi all,
>
> Given that this is a complex new class of binding, I'd appreciate if at least
> one other device tree maintainer could also take a look over this and voice any
> concerns or suggestions. I've left the entire patch context for this.
Here is just a gentle reminder. Looks like no one else has had the time
to provide us a third opinion on this work. Shall we continue
progressing here? Its been about four weeks the series is waiting on
extra feedback.
I was on paternity leave :-) So, getting back to get this one rolling.
>
> Apologies for the munged whitespace -- my mail server appears to have helpfully
> and irreparably replaced all tabs with spaces.
>
> On Tue, Oct 01, 2013 at 03:39:26AM +0100, Eduardo Valentin wrote:
>> This patch introduces a device tree bindings for
>> describing the hardware thermal behavior and limits.
>> Also a parser to read and interpret the data and feed
>> it in the thermal framework is presented.
>>
>> This patch introduces a thermal data parser for device
>> tree. The parsed data is used to build thermal zones
>> and thermal binding parameters. The output data
>> can then be used to deploy thermal policies.
>>
>> This patch adds also documentation regarding this
>> API and how to define tree nodes to use
>> this infrastructure.
>>
>> Note that, in order to be able to have control
>> on the sensor registration on the DT thermal zone,
>> it was required to allow changing the thermal zone
>> .get_temp callback. For this reason, this patch
>> also removes the 'const' modifier from the .ops
>> field of thermal zone devices.
>>
>> Cc: Zhang Rui <rui.zhang@intel.com>
>> Cc: linux-pm@vger.kernel.org
>> Cc: linux-kernel@vger.kernel.org
>> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
>> ---
>> Hello Mark, folks,
>>
>> So, here is v8. Pretty small changes. Most are better
>> English phrasing in the binding document. It follows changelog:
>> - Several rephrasing in the binding document, including
>> spelling, grammar and better phrasing.
>> - Removed WiP warning from binding document.
>> - Several spacing and formatting changes in the binding document
>> - Used the '-specifier' nomenclature properly in the binding doc
>> - Removed the optional property 'thermal-sensors-names', because
>> it does not provide useful runtime information
>> - Fixed description of 'polling-delay-passive'
>> - Improved examples by adding comments and better explanation
>> - s/fw/framework/g
>> - Added a WARN when sensors specifiers are greater and 1.
>>
>> All best,
>>
>> Eduardo
>>
>> ---
>> .../devicetree/bindings/thermal/thermal.txt | 587 ++++++++++++++
>> drivers/thermal/Kconfig | 13 +
>> drivers/thermal/Makefile | 1 +
>> drivers/thermal/of-thermal.c | 849 +++++++++++++++++++++
>> drivers/thermal/thermal_core.c | 9 +-
>> drivers/thermal/thermal_core.h | 9 +
>> include/dt-bindings/thermal/thermal.h | 27 +
>> include/linux/thermal.h | 28 +-
>> 8 files changed, 1520 insertions(+), 3 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
>> create mode 100644 drivers/thermal/of-thermal.c
>> create mode 100644 include/dt-bindings/thermal/thermal.h
>>
>> diff --git a/Documentation/devicetree/bindings/thermal/thermal.txt b/Documentation/devicetree/bindings/thermal/thermal.txt
>> new file mode 100644
>> index 0000000..ad06a8d
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/thermal/thermal.txt
>> @@ -0,0 +1,587 @@
>> +* Thermal Framework Device Tree descriptor
>> +
>> +This file describes a generic binding to provide a way of
>> +defining hardware thermal structure using device tree.
>
> s/defining/describing/
>
>> +A thermal structure includes thermal zones and their components,
>> +such as trip points, polling intervals, sensors and cooling devices
>> +binding descriptors.
>> +
>> +The target of device tree thermal descriptors is to describe only
>> +the hardware thermal aspects. The thermal device tree bindings are
>> +not about how the system must control or which algorithm or policy
>> +must be taken in place.
>
> I'm not quite sure what this is saying -- it seems to contradict the
> design of the binding where trip points get linked to cooling device
> configuration, and thus we're defining a policy along the lines of "when
> sensor $W hits temperature $X, configure cooling device $Y with value
> $Z". I don't see how that can't be considered policy.
>
> At best, we can say that policy is being defined because describing the
> physical properties of a device and dealing with this at runtime is not
> feasible.
>
>> +
>> +There are five types of nodes involved to describe thermal bindings:
>> +- sensors: used to describe the device source of temperature sensing;
>
> - thermal sensors: devices which may be used to take temperature
> measurements.
>
>> +- cooling devices: used to describe devices source of power dissipation control;
>
> - cooling devices: devices which may be used to dissipate heat.
>
>> +- trip points: used to describe points in temperature domain defined to
>> +make the system aware of hardware limits;
>
> - trip points: describe key temperatures at which cooling is recommended. The
> set of points should be chosen based on hardware limits.
>
>> +- cooling maps: used to describe links between trip points and cooling devices;
>> +- thermal zones: used to describe thermal data within the hardware;
>> +
>> +It follows a description of each type of these device tree nodes.
>
> How about:
>
> The following is a description of each of these node types.
>
>> +
>> +* Thermal sensor devices
>> +
>> +Thermal sensor devices are nodes providing temperature sensing capabilities on
>> +thermal zones. Typical devices are I2C ADC converters and bandgaps. These are
>> +nodes providing temperature data to thermal zones. Thermal sensor devices may
>> +control one or more internal sensors.
>> +
>> +Required property:
>> +- #thermal-sensor-cells: Used to provide sensor device specific information
>> + Type: unsigned while referring to it. Typically 0 on thermal sensor
>> + Size: one cell nodes with only one sensor, and at least 1 on nodes
>> + with several internal sensors, in order
>> + to identify uniquely the sensor instances within
>> + the IC. See thermal zone binding for more details
>> + on how consumers refer to sensor devices.
>> +
>> +* Cooling device nodes
>> +
>> +Cooling devices are nodes providing control on power dissipation. There
>> +are essentially two ways to provide control on power dissipation. First
>> +is by means of regulating device performance, which is known as passive
>> +cooling. A typical passive cooling is a CPU that has dynamic voltage and
>> +frequency scaling (DVFS), and uses lower frequencies as cooling states.
>> +Second is by means of activating devices in order to remove
>> +the dissipated heat, which is known as active cooling, e.g. regulating
>> +fan speeds. In both cases, cooling devices shall have a way to determine
>> +the state of cooling in which the device is.
>
> I'd probably say "heat dissipation" rather than "power dissipation", unless
> this is a technical term I am not aware of?
>
> Why is the determination of the state of the cooling device important?
>
>> +
>> +Required properties:
>> +- cooling-min-state: An integer indicating the smallest
>> + Type: unsigned cooling state accepted. Typically 0.
>> + Size: one cell
>> +
>> +- cooling-max-state: An integer indicating the largest
>> + Type: unsigned cooling state accepted.
>> + Size: one cell
>> +
>> +- #cooling-cells: Used to provide cooling device specific information
>> + Type: unsigned while referring to it. Must be at least 2, in order
>> + Size: one cell to specify minimum and maximum cooling state used
>> + in the reference. The first cell is the minimum
>> + cooling state requested and the second cell is
>> + the maximum cooling state requested in the reference.
>> + See Cooling device maps section below for more details
>> + on how consumers refer to cooling devices.
>
> Is it assumed that all the values between min and max are valid, or might this
> be a sparse set of cooling values?
>
>> +
>> +* Trip points
>> +
>> +The trip node is a node to describe a point in the temperature domain
>> +in which the system takes an action. This node describes just the point,
>> +not the action.
>> +
>> +Required properties:
>> +- temperature: An integer indicating the trip temperature level,
>> + Type: signed in millicelsius.
>> + Size: one cell
>> +
>> +- hysteresis: a (low) hysteresis value on 'temperature'. This is a
>> + Type: unsigned relative value, in millicelsius.
>> + Size: one cell
>
> What is it relative to?
>
> Why is 'temperature' in quotes?
>
>> +
>> +- type: a string containing the trip type. Supported values are:
>> + "active": A trip point to enable active cooling
>> + "passive": A trip point to enable passive cooling
>> + "hot": A trip point to notify emergency
>> + "critical": Hardware not reliable.
>> + Type: string
>> +
>> +There are also string constants defined at
>> +include/dt-bindings/thermal/thermal.h.
>
> Why?
>
>> +
>> +* Cooling device maps
>> +
>> +The cooling device maps node is a node to describe how cooling devices
>> +get assigned to trip points of the zone. The cooling devices are expected
>> +to be loaded in the target system.
>> +
>> +Required properties:
>> +- cooling-device: A phandle of a cooling device with its specifier,
>> + Type: phandle of referring to which cooling device is used in this
>> + cooling device binding. In the cooling specifier, the first cell
>> + is the minimum cooling state and the second cell
>> + is the maximum cooling state used in this map.
>
> The type is wrong here -- it's a phandle + cooling-cells, not just a phandle.
>
>> +- trip: A phandle of a trip point node within the same thermal
>> + Type: phandle of zone.
>> + trip point node
>> +
>> +Optional property:
>> +- contribution: The cooling contribution to the thermal zone of the
>> + Type: unsigned referred cooling device at the referred trip point.
>> + Size: one cell The contribution is a ratio of the sum
>> + of all cooling contributions within a thermal zone.
>> +
>> +Note: Using the THERMAL_NO_LIMIT (-1UL) constant in the cooling-device phandle
>> +limit specifier means:
>> +(i) - minimum state allowed for minimum cooling state used in the reference.
>> +(ii) - maximum state allowed for maximum cooling state used in the reference.
>> +Refer to include/dt-bindings/thermal/thermal.h for definition of this constant.
>> +
>> +* Thermal zone nodes
>> +
>> +The thermal zone node is the node containing all the required info
>> +for describing a thermal zone, including its cooling device bindings. The
>> +thermal zone node must contain, apart from its own properties, one sub-node
>> +containing trip nodes and one sub-node containing all the zone cooling maps.
>> +
>> +Required properties:
>> +- polling-delay: The maximum number of milliseconds to wait between polls
>> + Type: unsigned when checking this thermal zone.
>> + Size: one cell
>> +
>> +- polling-delay-passive: The maximum number of milliseconds to wait
>> + Type: unsigned between polls when performing passive cooling.
>> + Size: one cell
>> +
>> +- thermal-sensors: A list of thermal sensor phandles and sensor specifier
>> + Type: list of used while monitoring the thermal zone.
>> + sensor phandles
>
> The type is wrong here. A list of phandle + sensor specifiers.
>
>> +
>> +- trips: A sub-node which is a container of only trip point nodes
>> + Type: sub-node required to describe the thermal zone.
>> +
>> +- cooling-maps: A sub-node which is a container of only cooling device
>> + Type: sub-node map nodes, used to describe the relation between trips
>> + and cooling devices.
>> +
>> +Optional property:
>> +- coefficients: An array of integers (one signed cell) containing
>> + Type: array coefficients to compose a linear relation between
>> + Elem size: one cell the sensors listed in the thermal-sensors property.
>> + Elem type: signed Coefficients defaults to 1, in case this property
>> + is not specified. A simple linear polynomial is used:
>> + Z = c0 * x0 + c1 + x1 + ... + c(n-1) * x(n-1) + cn.
>> +
>> + The coefficients are ordered and they match with sensors
>> + by means of sensor ID. Additional coefficients are
>> + interpreted as constant offset.
>> +
>> +Note: The delay properties are bound to the maximum dT/dt (temperature
>> +derivative over time) in two situations for a thermal zone:
>> +(i) - when passive cooling is activated (polling-delay-passive); and
>> +(ii) - when the zone just needs to be monitored (polling-delay) or
>> +when active cooling is activated.
>> +
>> +The maximum dT/dt is highly bound to hardware power consumption and dissipation
>> +capability. The delays should be chosen to account for said max dT/dt,
>> +such that a device does not cross several trip boundaries unexpectedly
>> +between polls. Choosing the right polling delays shall avoid having the
>> +device in temperature ranges that may damage the silicon structures and
>> +reduce silicon lifetime.
>> +
>> +* The thermal-zones node
>> +
>> +The "thermal-zones" node is a container for all thermal zone nodes. It shall
>> +contain only sub-nodes describing thermal zones as in the section
>> +"Thermal zone nodes". The "thermal-zones" node appears under "/".
>> +
>> +* Examples
>> +
>> +Below are several examples on how to use thermal data descriptors
>> +using device tree bindings:
>> +
>> +(a) - CPU thermal zone
>> +
>> +The CPU thermal zone example below describes how to setup one thermal zone
>> +using one single sensor as temperature source and many cooling devices and
>> +power dissipation control sources.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +cpus {
>> + /*
>> + * Here is an example of describing a cooling device for a DVFS
>> + * capable CPU. The CPU node describes its four OPPs.
>> + * The cooling states possible are 0..3, and they are
>> + * used as OPP indexes. The minimum cooling state is 0, which means
>> + * all four OPPs can be available to the system. The maximum
>> + * cooling state is 3, which means only the lowest OPPs (198MHz@0.85V)
>> + * can be available in the system.
>> + */
>> + cpu0: cpu@0 {
>> + ...
>> + operating-points = <
>> + /* kHz uV */
>> + 970000 1200000
>> + 792000 1100000
>> + 396000 950000
>> + 198000 850000
>> + >;
>> + cooling-min-state = <0>;
>> + cooling-max-state = <3>;
>> + #cooling-cells = <2>; /* min followed by max */
>> + };
>> + ...
>> +};
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * A simple fan controller which supports 10 speeds of operation
>> + * (represented as 0-9).
>> + */
>> + fan0: fan@0x48 {
>> + ...
>> + cooling-min-state = <0>;
>> + cooling-max-state = <9>;
>> + #cooling-cells = <2>; /* min followed by max */
>> + };
>> +};
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with a single bandgap temperature sensor.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + thermal-sensors = <&bandgap0>;
>> +
>> + trips {
>> + cpu-alert0: cpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "active";
>> + };
>> + cpu-alert1: cpu-alert {
>> + temperature = <100000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + cpu-crit: cpu-crit {
>> + temperature = <125000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + map0 {
>> + trip = <&cpu-alert0>;
>> + cooling-device = <&fan0 THERMAL_NO_LIMITS 4>;
>> + };
>> + map1 {
>> + trip = <&cpu-alert1>;
>> + cooling-device = <&fan0 5 THERMAL_NO_LIMITS>;
>> + };
>> + map2 {
>> + trip = <&cpu-alert1>;
>> + cooling-device =
>> + <&cpu0 THERMAL_NO_LIMITS THERMAL_NO_LIMITS>;
>> + };
>> + };
>> + };
>> +};
>> +
>> +In the example above, the ADC sensor (bandgap0) at address 0x0000ED00 is
>> +used to monitor the zone 'cpu-thermal' using its sole sensor. A fan
>> +device (fan0) is controlled via I2C bus 1, at address 0x48, and has ten
>> +different cooling states 0-9. It is used to remove the heat out of
>> +the thermal zone 'cpu-thermal' using its cooling states
>> +from its minimum to 4, when it reaches trip point 'cpu-alert0'
>> +at 90C, as an example of active cooling. The same cooling device is used at
>> +'cpu-alert1', but from 5 to its maximum state. The cpu@0 device is also
>> +linked to the same thermal zone, 'cpu-thermal', as a passive cooling device,
>> +using all its cooling states at trip point 'cpu-alert1',
>> +which is a trip point at 100C. On the thermal zone 'cpu-thermal', at the
>> +temperature of 125C, represented by the trip point 'cpu-crit', the silicon
>> +is not reliable anymore.
>> +
>> +(b) - IC with several internal sensors
>> +
>> +The example below describes how to deploy several thermal zones based off a
>> +single sensor IC, assuming it has several internal sensors. This is a common
>> +case on SoC designs with several internal IPs that may need different thermal
>> +requirements, and thus may have their own sensor to monitor or detect internal
>> +hotspots in their silicon.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with several bandgap temperature sensors.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <1>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 0>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + cpu-alert: cpu-alert {
>> + temperature = <100000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + cpu-crit: cpu-crit {
>> + temperature = <125000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +
>> + gpu-thermal: gpu-thermal {
>> + polling-delay-passive = <120>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 1>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + gpu-alert: gpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + gpu-crit: gpu-crit {
>> + temperature = <105000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +
>> + dsp-thermal: dsp-thermal {
>> + polling-delay-passive = <50>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&bandgap0 2>;
>> +
>> + trips {
>> + /* each zone within the SoC may have its own trips */
>> + dsp-alert: gpu-alert {
>> + temperature = <90000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + dsp-crit: gpu-crit {
>> + temperature = <135000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + /* each zone within the SoC may have its own cooling */
>> + ...
>> + };
>> + };
>> +};
>> +
>> +In the example above, there is one bandgap IC which has the capability to
>> +monitor three sensors. The hardware has been designed so that sensors are
>> +placed on different places in the DIE to monitor different temperature
>> +hotspots: one for CPU thermal zone, one for GPU thermal zone and the
>> +other to monitor a DSP thermal zone.
>> +
>> +Thus, there is a need to assign each sensor provided by the bandgap IC
>> +to different thermal zones. This is achieved by means of using the
>> +#thermal-sensor-cells property and using the first cell of the sensor
>> +specifier as sensor ID. In the example, then, <bandgap 0> is used to
>> +monitor CPU thermal zone, <bandgap 1> is used to monitor GPU thermal
>> +zone and <bandgap 2> is used to monitor DSP thermal zone. Each zone
>> +may be uncorrelated, having its own dT/dt requirements, trips
>> +and cooling maps.
>> +
>> +
>> +(c) - Several sensors within one single thermal zone
>> +
>> +The example below illustrates how to use more than one sensor within
>> +one thermal zone.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * A simple IC with a single temperature sensor.
>> + */
>> + adc: sensor@0x49 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +ocp {
>> + ...
>> + /*
>> + * A simple IC with a single bandgap temperature sensor.
>> + */
>> + bandgap0: bandgap@0x0000ED00 {
>> + ...
>> + #thermal-sensor-cells = <0>;
>> + };
>> +};
>> +
>> +thermal-zones {
>> + cpu-thermal: cpu-thermal {
>> + polling-delay-passive = <250>; /* milliseconds */
>> + polling-delay = <1000>; /* milliseconds */
>> +
>> + thermal-sensors = <&bandgap0>, /* cpu */
>> + <&adc>; /* pcb north */
>> +
>> + /* hotspot = 100 * bandgap - 120 * adc + 484 */
>> + coefficients = <100 -120 484>;
>> +
>> + trips {
>> + ...
>> + };
>> +
>> + cooling-maps {
>> + ...
>> + };
>> + };
>> +};
>> +
>> +In some cases, there is a need to use more than one sensor to extrapolate
>> +a thermal hotspot in the silicon. The above example illustrates this situation.
>> +For instance, it may be the case that a sensor external to CPU IP may be placed
>> +close to CPU hotspot and together with internal CPU sensor, it is used
>> +to determine the hotspot. Assuming this is the case for the above example,
>> +the hypothetical extrapolation rule would be:
>> + hotspot = 100 * bandgap - 120 * adc + 484
>> +
>> +In other context, the same idea can be used to add fixed offset. For instance,
>> +consider the hotspot extrapolation rule below:
>> + hotspot = 1 * adc + 6000
>> +
>> +In the above equation, the hotspot is always 6C higher than what is read
>> +from the ADC sensor. The binding would be then:
>> + thermal-sensors = <&adc>;
>> +
>> + /* hotspot = 1 * adc + 6000 */
>> + coefficients = <1 6000>;
>> +
>> +(d) - Board thermal
>> +
>> +The board thermal example below illustrates how to setup one thermal zone
>> +with many sensors and many cooling devices.
>> +
>> +#include <dt-bindings/thermal/thermal.h>
>> +
>> +&i2c1 {
>> + ...
>> + /*
>> + * An IC with several temperature sensor.
>> + */
>> + adc-dummy: sensor@0x50 {
>> + ...
>> + #thermal-sensor-cells = <1>; /* sensor internal ID */
>> + };
>> +};
>> +
>> +thermal-zones {
>> + batt-thermal {
>> + polling-delay-passive = <500>; /* milliseconds */
>> + polling-delay = <2500>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&adc-dummy 4>;
>> +
>> + trips {
>> + ...
>> + };
>> +
>> + cooling-maps {
>> + ...
>> + };
>> + };
>> +
>> + board-thermal: board-thermal {
>> + polling-delay-passive = <1000>; /* milliseconds */
>> + polling-delay = <2500>; /* milliseconds */
>> +
>> + /* sensor ID */
>> + thermal-sensors = <&adc-dummy 0>, /* pcb top edge */
>> + <&adc-dummy 1>, /* lcd */
>> + <&adc-dymmy 2>; /* back cover */
>> + /*
>> + * An array of coefficients describing the sensor
>> + * linear relation. E.g.:
>> + * z = c1*x1 + c2*x2 + c3*x3
>> + */
>> + coefficients = <1200 -345 890>;
>> +
>> + trips {
>> + /* Trips are based on resulting linear equation */
>> + cpu-trip: cpu-trip {
>> + temperature = <60000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + gpu-trip: gpu-trip {
>> + temperature = <55000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + }
>> + lcd-trip: lcp-trip {
>> + temperature = <53000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "passive";
>> + };
>> + crit-trip: crit-trip {
>> + temperature = <68000>; /* millicelsius */
>> + hysteresis = <2000>; /* millicelsius */
>> + type = "critical";
>> + };
>> + };
>> +
>> + cooling-maps {
>> + map0 {
>> + trip = <&cpu-trip>;
>> + cooling-device = <&cpu0 0 2>;
>> + contribution = <55>;
>> + };
>> + map1 {
>> + trip = <&gpu-trip>;
>> + cooling-device = <&gpu0 0 2>;
>> + contribution = <20>;
>> + };
>> + map2 {
>> + trip = <&lcd-trip>;
>> + cooling-device = <&lcd0 5 10>;
>> + contribution = <15>;
>> + };
>> + };
>> + };
>> +};
>> +
>> +The above example is a mix of previous examples, a sensor IP with several internal
>> +sensors used to monitor different zones, one of them is composed by several sensors and
>> +with different cooling devices.
>> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
>> index dbfc390..dd81eb8 100644
>> --- a/drivers/thermal/Kconfig
>> +++ b/drivers/thermal/Kconfig
>> @@ -29,6 +29,19 @@ config THERMAL_HWMON
>> Say 'Y' here if you want all thermal sensors to
>> have hwmon sysfs interface too.
>>
>> +config THERMAL_OF
>> + bool
>> + prompt "APIs to parse thermal data out of device tree"
>> + depends on OF
>> + default y
>> + help
>> + This options provides helpers to add the support to
>> + read and parse thermal data definitions out of the
>> + device tree blob.
>> +
>> + Say 'Y' here if you need to build thermal infrastructure
>> + based on device tree.
>> +
>> choice
>> prompt "Default Thermal governor"
>> default THERMAL_DEFAULT_GOV_STEP_WISE
>> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
>> index 584b363..4b03956 100644
>> --- a/drivers/thermal/Makefile
>> +++ b/drivers/thermal/Makefile
>> @@ -7,6 +7,7 @@ thermal_sys-y += thermal_core.o
>>
>> # interface to/from other layers providing sensors
>> thermal_sys-$(CONFIG_THERMAL_HWMON) += thermal_hwmon.o
>> +thermal_sys-$(CONFIG_THERMAL_OF) += of-thermal.o
>>
>> # governors
>> thermal_sys-$(CONFIG_THERMAL_GOV_FAIR_SHARE) += fair_share.o
>> diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
>> new file mode 100644
>> index 0000000..66f9eb2
>> --- /dev/null
>> +++ b/drivers/thermal/of-thermal.c
>> @@ -0,0 +1,849 @@
>> +/*
>> + * of-thermal.c - Generic Thermal Management device tree support.
>> + *
>> + * Copyright (C) 2013 Texas Instruments
>> + * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
>> + *
>> + *
>> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; version 2 of the License.
>> + *
>> + * This program is distributed in the hope that it will be useful, but
>> + * WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> + * General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License along
>> + * with this program; if not, write to the Free Software Foundation, Inc.,
>> + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
>> + *
>> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> + */
>> +#include <linux/thermal.h>
>> +#include <linux/slab.h>
>> +#include <linux/types.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/err.h>
>> +#include <linux/export.h>
>> +#include <linux/string.h>
>> +
>> +#include "thermal_core.h"
>> +
>> +/*** Private data structures to represent thermal device tree data ***/
>> +
>> +/**
>> + * struct __thermal_trip - representation of a point in temperature domain
>> + * @np: pointer to struct device_node that this trip point was created from
>> + * @temperature: temperature value in miliCelsius
>> + * @hysteresis: relative hysteresis in miliCelsius
>> + * @type: trip point type
>> + */
>> +
>> +struct __thermal_trip {
>> + struct device_node *np;
>> + unsigned long int temperature;
>> + unsigned long int hysteresis;
>> + enum thermal_trip_type type;
>> +};
>> +
>> +/**
>> + * struct __thermal_bind_param - a match between trip and cooling device
>> + * @cooling_device: a pointer to identify the referred cooling device
>> + * @trip_id: the trip point index
>> + * @usage: the percentage (from 0 to 100) of cooling contribution
>> + * @min: minimum cooling state used at this trip point
>> + * @max: maximum cooling state used at this trip point
>> + */
>> +
>> +struct __thermal_bind_params {
>> + struct device_node *cooling_device;
>> + unsigned int trip_id;
>> + unsigned int usage;
>> + unsigned long min;
>> + unsigned long max;
>> +};
>> +
>> +/**
>> + * struct __thermal_zone - internal representation of a thermal zone
>> + * @mode: current thermal zone device mode (enabled/disabled)
>> + * @passive_delay: polling interval while passive cooling is activated
>> + * @polling_delay: zone polling interval
>> + * @ntrips: number of trip points
>> + * @trips: an array of trip points (0..ntrips - 1)
>> + * @num_tbps: number of thermal bind params
>> + * @tbps: an array of thermal bind params (0..num_tbps - 1)
>> + * @sensor_data: sensor private data used while reading temperature and trend
>> + * @get_temp: sensor callback to read temperature
>> + * @get_trend: sensor callback to read temperature trend
>> + */
>> +
>> +struct __thermal_zone {
>> + enum thermal_device_mode mode;
>> + int passive_delay;
>> + int polling_delay;
>> +
>> + /* trip data */
>> + int ntrips;
>> + struct __thermal_trip *trips;
>> +
>> + /* cooling binding data */
>> + int num_tbps;
>> + struct __thermal_bind_params *tbps;
>> +
>> + /* sensor interface */
>> + void *sensor_data;
>> + int (*get_temp)(void *, long *);
>> + int (*get_trend)(void *, long *);
>> +};
>> +
>> +/*** DT thermal zone device callbacks ***/
>> +
>> +static int of_thermal_get_temp(struct thermal_zone_device *tz,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (!data->get_temp)
>> + return -EINVAL;
>> +
>> + return data->get_temp(data->sensor_data, temp);
>> +}
>> +
>> +static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
>> + enum thermal_trend *trend)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> + long dev_trend;
>> + int r;
>> +
>> + if (!data->get_trend)
>> + return -EINVAL;
>> +
>> + r = data->get_trend(data->sensor_data, &dev_trend);
>> + if (r)
>> + return r;
>> +
>> + /* TODO: These intervals might have some thresholds, but in core code */
>> + if (dev_trend > 0)
>> + *trend = THERMAL_TREND_RAISING;
>> + else if (dev_trend < 0)
>> + *trend = THERMAL_TREND_DROPPING;
>> + else
>> + *trend = THERMAL_TREND_STABLE;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_bind(struct thermal_zone_device *thermal,
>> + struct thermal_cooling_device *cdev)
>> +{
>> + struct __thermal_zone *data = thermal->devdata;
>> + int i;
>> +
>> + if (!data || IS_ERR(data))
>> + return -ENODEV;
>> +
>> + /* find where to bind */
>> + for (i = 0; i < data->num_tbps; i++) {
>> + struct __thermal_bind_params *tbp = data->tbps + i;
>> +
>> + if (tbp->cooling_device == cdev->np) {
>> + int ret;
>> +
>> + ret = thermal_zone_bind_cooling_device(thermal,
>> + tbp->trip_id, cdev,
>> + tbp->min,
>> + tbp->max);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_unbind(struct thermal_zone_device *thermal,
>> + struct thermal_cooling_device *cdev)
>> +{
>> + struct __thermal_zone *data = thermal->devdata;
>> + int i;
>> +
>> + if (!data || IS_ERR(data))
>> + return -ENODEV;
>> +
>> + /* find where to unbind */
>> + for (i = 0; i < data->num_tbps; i++) {
>> + struct __thermal_bind_params *tbp = data->tbps + i;
>> +
>> + if (tbp->cooling_device == cdev->np) {
>> + int ret;
>> +
>> + ret = thermal_zone_unbind_cooling_device(thermal,
>> + tbp->trip_id, cdev);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_mode(struct thermal_zone_device *tz,
>> + enum thermal_device_mode *mode)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + *mode = data->mode;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_mode(struct thermal_zone_device *tz,
>> + enum thermal_device_mode mode)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + mutex_lock(&tz->lock);
>> +
>> + if (mode == THERMAL_DEVICE_ENABLED)
>> + tz->polling_delay = data->polling_delay;
>> + else
>> + tz->polling_delay = 0;
>> +
>> + mutex_unlock(&tz->lock);
>> +
>> + data->mode = mode;
>> + thermal_zone_device_update(tz);
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
>> + enum thermal_trip_type *type)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *type = data->trips[trip].type;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *temp = data->trips[trip].temperature;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
>> + unsigned long temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + /* thermal framework should take care of data->mask & (1 << trip) */
>> + data->trips[trip].temperature = temp;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
>> + unsigned long *hyst)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + *hyst = data->trips[trip].hysteresis;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
>> + unsigned long hyst)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> +
>> + if (trip >= data->ntrips || trip < 0)
>> + return -EDOM;
>> +
>> + /* thermal framework should take care of data->mask & (1 << trip) */
>> + data->trips[trip].hysteresis = hyst;
>> +
>> + return 0;
>> +}
>> +
>> +static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
>> + unsigned long *temp)
>> +{
>> + struct __thermal_zone *data = tz->devdata;
>> + int i;
>> +
>> + for (i = 0; i < data->ntrips; i++)
>> + if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
>> + *temp = data->trips[i].temperature;
>> + return 0;
>> + }
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static struct thermal_zone_device_ops of_thermal_ops = {
>> + .get_mode = of_thermal_get_mode,
>> + .set_mode = of_thermal_set_mode,
>> +
>> + .get_trip_type = of_thermal_get_trip_type,
>> + .get_trip_temp = of_thermal_get_trip_temp,
>> + .set_trip_temp = of_thermal_set_trip_temp,
>> + .get_trip_hyst = of_thermal_get_trip_hyst,
>> + .set_trip_hyst = of_thermal_set_trip_hyst,
>> + .get_crit_temp = of_thermal_get_crit_temp,
>> +
>> + .bind = of_thermal_bind,
>> + .unbind = of_thermal_unbind,
>> +};
>> +
>> +/*** sensor API ***/
>> +
>> +static struct thermal_zone_device *
>> +thermal_zone_of_add_sensor(struct device_node *zone,
>> + struct device_node *sensor, void *data,
>> + int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + struct thermal_zone_device *tzd;
>> + struct __thermal_zone *tz;
>> +
>> + tzd = thermal_zone_get_zone_by_name(zone->name);
>> + if (IS_ERR(tzd))
>> + return ERR_PTR(-EPROBE_DEFER);
>> +
>> + tz = tzd->devdata;
>> +
>> + mutex_lock(&tzd->lock);
>> + tz->get_temp = get_temp;
>> + tz->get_trend = get_trend;
>> + tz->sensor_data = data;
>> +
>> + tzd->ops->get_temp = of_thermal_get_temp;
>> + tzd->ops->get_trend = of_thermal_get_trend;
>> + mutex_unlock(&tzd->lock);
>> +
>> + return tzd;
>> +}
>> +
>> +/**
>> + * thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
>> + * @dev: a valid struct device pointer of a sensor device. Must contain
>> + * a valid .of_node, for the sensor node.
>> + * @sensor_id: a sensor identifier, in case the sensor IP has more
>> + * than one sensors
>> + * @data: a private pointer (owned by the caller) that will be passed
>> + * back, when a temperature reading is needed.
>> + * @get_temp: a pointer to a function that reads the sensor temperature.
>> + * @get_trend: a pointer to a function that reads the sensor temperature trend.
>> + *
>> + * This function will search the list of thermal zones described in device
>> + * tree and look for the zone that refer to the sensor device pointed by
>> + * @dev->of_node as temperature providers. For the zone pointing to the
>> + * sensor node, the sensor will be added to the DT thermal zone device.
>> + *
>> + * The thermal zone temperature is provided by the @get_temp function
>> + * pointer. When called, it will have the private pointer @data back.
>> + *
>> + * The thermal zone temperature trend is provided by the @get_trend function
>> + * pointer. When called, it will have the private pointer @data back.
>> + *
>> + * TODO:
>> + * 01 - This function must enqueue the new sensor instead of using
>> + * it as the only source of temperature values.
>> + *
>> + * 02 - There must be a way to match the sensor with all thermal zones
>> + * that refer to it.
>> + *
>> + * Return: On success returns a valid struct thermal_zone_device,
>> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
>> + * check the return value with help of IS_ERR() helper.
>> + */
>> +struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int sensor_id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + struct device_node *np, *child, *sensor_np;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np)
>> + return ERR_PTR(-ENODEV);
>> +
>> + if (!dev || !dev->of_node)
>> + return ERR_PTR(-EINVAL);
>> +
>> + sensor_np = dev->of_node;
>> +
>> + for_each_child_of_node(np, child) {
>> + struct of_phandle_args sensor_specs;
>> + int ret, id;
>> +
>> + /* For now, thermal framework supports only 1 sensor per zone */
>> + ret = of_parse_phandle_with_args(child, "thermal-sensors",
>> + "#thermal-sensor-cells",
>> + 0, &sensor_specs);
>> + if (ret)
>> + continue;
>> +
>> + if (sensor_specs.args_count >= 1) {
>> + id = sensor_specs.args[0];
>> + WARN(sensor_specs.args_count > 1,
>> + "%s: too many cells in sensor specifier %d\n",
>> + sensor_specs.np->name, sensor_specs.args_count);
>> + } else {
>> + id = 0;
>> + }
>> +
>> + if (sensor_specs.np == sensor_np && id == sensor_id) {
>> + of_node_put(np);
>> + return thermal_zone_of_add_sensor(child, sensor_np,
>> + data,
>> + get_temp,
>> + get_trend);
>> + }
>> + }
>> + of_node_put(np);
>> +
>> + return ERR_PTR(-ENODEV);
>> +}
>> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
>> +
>> +/**
>> + * thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
>> + * @dev: a valid struct device pointer of a sensor device. Must contain
>> + * a valid .of_node, for the sensor node.
>> + * @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
>> + *
>> + * This function removes the sensor callbacks and private data from the
>> + * thermal zone device registered with thermal_zone_of_sensor_register()
>> + * API. It will also silent the zone by remove the .get_temp() and .get_trend()
>> + * thermal zone device callbacks.
>> + *
>> + * TODO: When the support to several sensors per zone is added, this
>> + * function must search the sensor list based on @dev parameter.
>> + *
>> + */
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tzd)
>> +{
>> + struct __thermal_zone *tz;
>> +
>> + if (!dev || !tzd || !tzd->devdata)
>> + return;
>> +
>> + tz = tzd->devdata;
>> +
>> + /* no __thermal_zone, nothing to be done */
>> + if (!tz)
>> + return;
>> +
>> + mutex_lock(&tzd->lock);
>> + tzd->ops->get_temp = NULL;
>> + tzd->ops->get_trend = NULL;
>> +
>> + tz->get_temp = NULL;
>> + tz->get_trend = NULL;
>> + tz->sensor_data = NULL;
>> + mutex_unlock(&tzd->lock);
>> +}
>> +EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
>> +
>> +/*** functions parsing device tree nodes ***/
>> +
>> +/**
>> + * thermal_of_populate_bind_params - parse and fill cooling map data
>> + * @np: DT node containing a cooling-map node
>> + * @__tbp: data structure to be filled with cooling map info
>> + * @trips: array of thermal zone trip points
>> + * @ntrips: number of trip points inside trips.
>> + *
>> + * This function parses a cooling-map type of node represented by
>> + * @np parameter and fills the read data into @__tbp data structure.
>> + * It needs the already parsed array of trip points of the thermal zone
>> + * in consideration.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + */
>> +static int thermal_of_populate_bind_params(struct device_node *np,
>> + struct __thermal_bind_params *__tbp,
>> + struct __thermal_trip *trips,
>> + int ntrips)
>> +{
>> + struct of_phandle_args cooling_spec;
>> + struct device_node *trip;
>> + int ret, i;
>> + u32 prop;
>> +
>> + /* Default weight. Usage is optional */
>> + __tbp->usage = 0;
>> + ret = of_property_read_u32(np, "contribution", &prop);
>> + if (ret == 0)
>> + __tbp->usage = prop;
>> +
>> + trip = of_parse_phandle(np, "trip", 0);
>> + if (!trip) {
>> + pr_err("missing trip property\n");
>> + return -ENODEV;
>> + }
>> +
>> + /* match using device_node */
>> + for (i = 0; i < ntrips; i++)
>> + if (trip == trips[i].np) {
>> + __tbp->trip_id = i;
>> + break;
>> + }
>> +
>> + if (i == ntrips) {
>> + ret = -ENODEV;
>> + goto end;
>> + }
>> +
>> + ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
>> + 0, &cooling_spec);
>> + if (ret < 0) {
>> + pr_err("missing cooling_device property\n");
>> + goto end;
>> + }
>> + __tbp->cooling_device = cooling_spec.np;
>> + if (cooling_spec.args_count >= 2) { /* at least min and max */
>> + __tbp->min = cooling_spec.args[0];
>> + __tbp->max = cooling_spec.args[1];
>> + } else {
>> + pr_err("wrong reference to cooling device, missing limits\n");
>> + }
>> +
>> +end:
>> + of_node_put(trip);
>> +
>> + return ret;
>> +}
>> +
>> +/**
>> + * It maps 'enum thermal_trip_type' found in include/linux/thermal.h
>> + * into the device tree binding of 'trip', property type.
>> + */
>> +static const char * const trip_types[] = {
>> + [THERMAL_TRIP_ACTIVE] = "active",
>> + [THERMAL_TRIP_PASSIVE] = "passive",
>> + [THERMAL_TRIP_HOT] = "hot",
>> + [THERMAL_TRIP_CRITICAL] = "critical",
>> +};
>> +
>> +/**
>> + * thermal_of_get_trip_type - Get phy mode for given device_node
>> + * @np: Pointer to the given device_node
>> + * @type: Pointer to resulting trip type
>> + *
>> + * The function gets trip type string from property 'type',
>> + * and store its index in trip_types table in @type,
>> + *
>> + * Return: 0 on success, or errno in error case.
>> + */
>> +static int thermal_of_get_trip_type(struct device_node *np,
>> + enum thermal_trip_type *type)
>> +{
>> + const char *t;
>> + int err, i;
>> +
>> + err = of_property_read_string(np, "type", &t);
>> + if (err < 0)
>> + return err;
>> +
>> + for (i = 0; i < ARRAY_SIZE(trip_types); i++)
>> + if (!strcasecmp(t, trip_types[i])) {
>> + *type = i;
>> + return 0;
>> + }
>> +
>> + return -ENODEV;
>> +}
>> +
>> +/**
>> + * thermal_of_populate_trip - parse and fill one trip point data
>> + * @np: DT node containing a trip point node
>> + * @trip: trip point data structure to be filled up
>> + *
>> + * This function parses a trip point type of node represented by
>> + * @np parameter and fills the read data into @trip data structure.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + */
>> +static int thermal_of_populate_trip(struct device_node *np,
>> + struct __thermal_trip *trip)
>> +{
>> + int prop;
>> + int ret;
>> +
>> + ret = of_property_read_u32(np, "temperature", &prop);
>> + if (ret < 0) {
>> + pr_err("missing temperature property\n");
>> + return ret;
>> + }
>> + trip->temperature = prop;
>> +
>> + ret = of_property_read_u32(np, "hysteresis", &prop);
>> + if (ret < 0) {
>> + pr_err("missing hysteresis property\n");
>> + return ret;
>> + }
>> + trip->hysteresis = prop;
>> +
>> + ret = thermal_of_get_trip_type(np, &trip->type);
>> + if (ret < 0) {
>> + pr_err("wrong trip type property\n");
>> + return ret;
>> + }
>> +
>> + /* Required for cooling map matching */
>> + trip->np = np;
>> +
>> + return 0;
>> +}
>> +
>> +/**
>> + * thermal_of_build_thermal_zone - parse and fill one thermal zone data
>> + * @np: DT node containing a thermal zone node
>> + *
>> + * This function parses a thermal zone type of node represented by
>> + * @np parameter and fills the read data into a __thermal_zone data structure
>> + * and return this pointer.
>> + *
>> + * TODO: Missing properties to parse: thermal-sensor-names and coefficients
>> + *
>> + * Return: On success returns a valid struct __thermal_zone,
>> + * otherwise, it returns a corresponding ERR_PTR(). Caller must
>> + * check the return value with help of IS_ERR() helper.
>> + */
>> +static struct __thermal_zone *
>> +thermal_of_build_thermal_zone(struct device_node *np)
>> +{
>> + struct device_node *child = NULL, *gchild;
>> + struct __thermal_zone *tz;
>> + int ret, i;
>> + u32 prop;
>> +
>> + if (!np) {
>> + pr_err("no thermal zone np\n");
>> + return ERR_PTR(-EINVAL);
>> + }
>> +
>> + tz = kzalloc(sizeof(*tz), GFP_KERNEL);
>> + if (!tz)
>> + return ERR_PTR(-ENOMEM);
>> +
>> + ret = of_property_read_u32(np, "polling-delay-passive", &prop);
>> + if (ret < 0) {
>> + pr_err("missing polling-delay-passive property\n");
>> + goto free_tz;
>> + }
>> + tz->passive_delay = prop;
>> +
>> + ret = of_property_read_u32(np, "polling-delay", &prop);
>> + if (ret < 0) {
>> + pr_err("missing polling-delay property\n");
>> + goto free_tz;
>> + }
>> + tz->polling_delay = prop;
>> +
>> + /* trips */
>> + child = of_get_child_by_name(np, "trips");
>> +
>> + /* No trips provided */
>> + if (!child)
>> + goto finish;
>> +
>> + tz->ntrips = of_get_child_count(child);
>> + if (tz->ntrips == 0) /* must have at least one child */
>> + goto finish;
>> +
>> + tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
>> + if (!tz->trips) {
>> + ret = -ENOMEM;
>> + goto free_tz;
>> + }
>> +
>> + i = 0;
>> + for_each_child_of_node(child, gchild) {
>> + ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
>> + if (ret)
>> + goto free_trips;
>> + }
>> +
>> + of_node_put(child);
>> +
>> + /* cooling-maps */
>> + child = of_get_child_by_name(np, "cooling-maps");
>> +
>> + /* cooling-maps not provided */
>> + if (!child)
>> + goto finish;
>> +
>> + tz->num_tbps = of_get_child_count(child);
>> + if (tz->num_tbps == 0)
>> + goto finish;
>> +
>> + tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
>> + if (!tz->tbps) {
>> + ret = -ENOMEM;
>> + goto free_trips;
>> + }
>> +
>> + i = 0;
>> + for_each_child_of_node(child, gchild)
>> + ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
>> + tz->trips, tz->ntrips);
>> + if (ret)
>> + goto free_tbps;
>> +
>> +finish:
>> + of_node_put(child);
>> + tz->mode = THERMAL_DEVICE_DISABLED;
>> +
>> + return tz;
>> +
>> +free_tbps:
>> + kfree(tz->tbps);
>> +free_trips:
>> + kfree(tz->trips);
>> +free_tz:
>> + kfree(tz);
>> + of_node_put(child);
>> +
>> + return ERR_PTR(ret);
>> +}
>> +
>> +static inline void of_thermal_free_zone(struct __thermal_zone *tz)
>> +{
>> + kfree(tz->tbps);
>> + kfree(tz->trips);
>> + kfree(tz);
>> +}
>> +
>> +/**
>> + * of_parse_thermal_zones - parse device tree thermal data
>> + *
>> + * Initialization function that can be called by machine initialization
>> + * code to parse thermal data and populate the thermal framework
>> + * with hardware thermal zones info. This function only parses thermal zones.
>> + * Cooling devices and sensor devices nodes are supposed to be parsed
>> + * by their respective drivers.
>> + *
>> + * Return: 0 on success, proper error code otherwise
>> + *
>> + */
>> +int __init of_parse_thermal_zones(void)
>> +{
>> + struct device_node *np, *child;
>> + struct __thermal_zone *tz;
>> + struct thermal_zone_device_ops *ops;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np) {
>> + pr_debug("unable to find thermal zones\n");
>> + return 0; /* Run successfully on systems without thermal DT */
>> + }
>> +
>> + for_each_child_of_node(np, child) {
>> + struct thermal_zone_device *zone;
>> + struct thermal_zone_params *tzp;
>> +
>> + tz = thermal_of_build_thermal_zone(child);
>> + if (IS_ERR(tz)) {
>> + pr_err("failed to build thermal zone %s: %ld\n",
>> + child->name,
>> + PTR_ERR(tz));
>> + continue;
>> + }
>> +
>> + ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
>> + if (!ops)
>> + goto exit_free;
>> +
>> + tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
>> + if (!tzp) {
>> + kfree(ops);
>> + goto exit_free;
>> + }
>> +
>> + /* No hwmon because there might be hwmon drivers registering */
>> + tzp->no_hwmon = true;
>> +
>> + zone = thermal_zone_device_register(child->name, tz->ntrips,
>> + 0, tz,
>> + ops, tzp,
>> + tz->passive_delay,
>> + tz->polling_delay);
>> + if (IS_ERR(zone)) {
>> + pr_err("Failed to build %s zone %ld\n", child->name,
>> + PTR_ERR(zone));
>> + kfree(tzp);
>> + kfree(ops);
>> + of_thermal_free_zone(tz);
>> + /* attempting to build remaining zones still */
>> + }
>> + }
>> +
>> + return 0;
>> +
>> +exit_free:
>> + of_thermal_free_zone(tz);
>> +
>> + /* no memory available, so free what we have built */
>> + of_thermal_destroy_zones();
>> +
>> + return -ENOMEM;
>> +}
>> +
>> +/**
>> + * of_thermal_destroy_zones - remove all zones parsed and allocated resources
>> + *
>> + * Finds all zones parsed and added to the thermal framework and remove them
>> + * from the system, together with their resources.
>> + *
>> + */
>> +void __exit of_thermal_destroy_zones(void)
>> +{
>> + struct device_node *np, *child;
>> +
>> + np = of_find_node_by_name(NULL, "thermal-zones");
>> + if (!np) {
>> + pr_err("unable to find thermal zones\n");
>> + return;
>> + }
>> +
>> + for_each_child_of_node(np, child) {
>> + struct thermal_zone_device *zone;
>> +
>> + zone = thermal_zone_get_zone_by_name(child->name);
>> + if (IS_ERR(zone))
>> + continue;
>> +
>> + thermal_zone_device_unregister(zone);
>> + kfree(zone->tzp);
>> + kfree(zone->ops);
>> + of_thermal_free_zone(zone->devdata);
>> + }
>> +}
>> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
>> index f7a9f4f..fec3351 100644
>> --- a/drivers/thermal/thermal_core.c
>> +++ b/drivers/thermal/thermal_core.c
>> @@ -1371,7 +1371,7 @@ static void remove_trip_attrs(struct thermal_zone_device *tz)
>> */
>> struct thermal_zone_device *thermal_zone_device_register(const char *type,
>> int trips, int mask, void *devdata,
>> - const struct thermal_zone_device_ops *ops,
>> + struct thermal_zone_device_ops *ops,
>> const struct thermal_zone_params *tzp,
>> int passive_delay, int polling_delay)
>> {
>> @@ -1751,8 +1751,14 @@ static int __init thermal_init(void)
>> if (result)
>> goto unregister_class;
>>
>> + result = of_parse_thermal_zones();
>> + if (result)
>> + goto exit_netlink;
>> +
>> return 0;
>>
>> +exit_netlink:
>> + genetlink_exit();
>> unregister_governors:
>> thermal_unregister_governors();
>> unregister_class:
>> @@ -1768,6 +1774,7 @@ error:
>>
>> static void __exit thermal_exit(void)
>> {
>> + of_thermal_destroy_zones();
>> genetlink_exit();
>> class_unregister(&thermal_class);
>> thermal_unregister_governors();
>> diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
>> index 7cf2f66..3db339f 100644
>> --- a/drivers/thermal/thermal_core.h
>> +++ b/drivers/thermal/thermal_core.h
>> @@ -77,4 +77,13 @@ static inline int thermal_gov_user_space_register(void) { return 0; }
>> static inline void thermal_gov_user_space_unregister(void) {}
>> #endif /* CONFIG_THERMAL_GOV_USER_SPACE */
>>
>> +/* device tree support */
>> +#ifdef CONFIG_THERMAL_OF
>> +int of_parse_thermal_zones(void);
>> +void of_thermal_destroy_zones(void);
>> +#else
>> +static inline int of_parse_thermal_zones(void) { return 0; }
>> +static inline void of_thermal_destroy_zones(void) { }
>> +#endif
>> +
>> #endif /* __THERMAL_CORE_H__ */
>> diff --git a/include/dt-bindings/thermal/thermal.h b/include/dt-bindings/thermal/thermal.h
>> new file mode 100644
>> index 0000000..59c4581
>> --- /dev/null
>> +++ b/include/dt-bindings/thermal/thermal.h
>> @@ -0,0 +1,27 @@
>> +/*
>> + * This header provides constants for most thermal bindings.
>> + *
>> + * Copyright (C) 2013 Texas Instruments
>> + * Eduardo Valentin <eduardo.valentin@ti.com>
>> + *
>> + * GPLv2 only
>> + */
>> +
>> +#ifndef _DT_BINDINGS_THERMAL_THERMAL_H
>> +#define _DT_BINDINGS_THERMAL_THERMAL_H
>> +
>> +/*
>> + * Here are the thermal trip types. This must
>> + * match with enum thermal_trip_type at
>> + * include/linux/thermal.h
>> + */
>> +#define THERMAL_TRIP_ACTIVE "active"
>> +#define THERMAL_TRIP_PASSIVE "passive"
>> +#define THERMAL_TRIP_HOT "hot"
>> +#define THERMAL_TRIP_CRITICAL "critical"
>
> I don't like this. If someone wants to include this in a C file they can't do so
> at the same time as include/linux/thermal.h. The defined names are longer than
> the actual string values, and the comment makes it sound like these could be
> modified rather than being a fixed ABI.
>
> I do not see the point of these constants.
>
> Thanks,
> Mark.
>
>> +
>> +/* On cooling devices upper and lower limits */
>> +#define THERMAL_NO_LIMIT (-1UL)
>> +
>> +#endif
>> +
>> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
>> index b268d3c..b780c5b 100644
>> --- a/include/linux/thermal.h
>> +++ b/include/linux/thermal.h
>> @@ -143,6 +143,7 @@ struct thermal_cooling_device {
>> int id;
>> char type[THERMAL_NAME_LENGTH];
>> struct device device;
>> + struct device_node *np;
>> void *devdata;
>> const struct thermal_cooling_device_ops *ops;
>> bool updated; /* true if the cooling device does not need update */
>> @@ -172,7 +173,7 @@ struct thermal_zone_device {
>> int emul_temperature;
>> int passive;
>> unsigned int forced_passive;
>> - const struct thermal_zone_device_ops *ops;
>> + struct thermal_zone_device_ops *ops;
>> const struct thermal_zone_params *tzp;
>> struct thermal_governor *governor;
>> struct list_head thermal_instances;
>> @@ -242,8 +243,31 @@ struct thermal_genl_event {
>> };
>>
>> /* Function declarations */
>> +#ifdef CONFIG_THERMAL_OF
>> +struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *));
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tz);
>> +#else
>> +static inline struct thermal_zone_device *
>> +thermal_zone_of_sensor_register(struct device *dev, int id,
>> + void *data, int (*get_temp)(void *, long *),
>> + int (*get_trend)(void *, long *))
>> +{
>> + return NULL;
>> +}
>> +
>> +static inline
>> +void thermal_zone_of_sensor_unregister(struct device *dev,
>> + struct thermal_zone_device *tz)
>> +{
>> +}
>> +
>> +#endif
>> struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
>> - void *, const struct thermal_zone_device_ops *,
>> + void *, struct thermal_zone_device_ops *,
>> const struct thermal_zone_params *, int, int);
>> void thermal_zone_device_unregister(struct thermal_zone_device *);
>>
>> --
>> 1.8.2.1.342.gfa7285d
>>
>>
>
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 295 bytes --]
^ permalink raw reply [flat|nested] 31+ messages in thread
* [PATCHv4 05/18] thermal: cpu_cooling: introduce of_cpufreq_cooling_register
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (2 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv7 03/18] thermal: introduce device tree parser Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 06/18] cpufreq: cpufreq-cpu0: add dt node parsing for cooling device properties Eduardo Valentin
` (10 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin
This patch introduces an API to register cpufreq cooling device
based on device tree node.
The registration via device tree node differs from normal
registration due to the fact that it is needed to fill
the device_node structure in order to be able to match
the cooling devices with trip points.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
drivers/thermal/Kconfig | 1 +
drivers/thermal/cpu_cooling.c | 56 ++++++++++++++++++++++++++++++++++++++-----
include/linux/cpu_cooling.h | 25 +++++++++++++++++++
3 files changed, 76 insertions(+), 6 deletions(-)
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index dd81eb8..9e7cc3f 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -91,6 +91,7 @@ config THERMAL_GOV_USER_SPACE
config CPU_THERMAL
bool "generic cpu cooling support"
depends on CPU_FREQ
+ depends on THERMAL_OF
select CPU_FREQ_TABLE
help
This implements the generic cpu cooling mechanism through frequency
diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index d179028..b7db93a 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -417,18 +417,21 @@ static struct notifier_block thermal_cpufreq_notifier_block = {
};
/**
- * cpufreq_cooling_register - function to create cpufreq cooling device.
+ * __cpufreq_cooling_register - helper function to create cpufreq cooling device
+ * @np: a valid struct device_node to the cooling device device tree node
* @clip_cpus: cpumask of cpus where the frequency constraints will happen.
*
* This interface function registers the cpufreq cooling device with the name
* "thermal-cpufreq-%x". This api can support multiple instances of cpufreq
- * cooling devices.
+ * cooling devices. It also gives the opportunity to link the cooling device
+ * with a device tree node, in order to bind it via the thermal DT code.
*
* Return: a valid struct thermal_cooling_device pointer on success,
* on failure, it returns a corresponding ERR_PTR().
*/
-struct thermal_cooling_device *
-cpufreq_cooling_register(const struct cpumask *clip_cpus)
+static struct thermal_cooling_device *
+__cpufreq_cooling_register(struct device_node *np,
+ const struct cpumask *clip_cpus)
{
struct thermal_cooling_device *cool_dev;
struct cpufreq_cooling_device *cpufreq_dev = NULL;
@@ -467,8 +470,8 @@ cpufreq_cooling_register(const struct cpumask *clip_cpus)
snprintf(dev_name, sizeof(dev_name), "thermal-cpufreq-%d",
cpufreq_dev->id);
- cool_dev = thermal_cooling_device_register(dev_name, cpufreq_dev,
- &cpufreq_cooling_ops);
+ cool_dev = thermal_of_cooling_device_register(np, dev_name, cpufreq_dev,
+ &cpufreq_cooling_ops);
if (!cool_dev) {
release_idr(&cpufreq_idr, cpufreq_dev->id);
kfree(cpufreq_dev);
@@ -488,9 +491,50 @@ cpufreq_cooling_register(const struct cpumask *clip_cpus)
return cool_dev;
}
+
+/**
+ * cpufreq_cooling_register - function to create cpufreq cooling device.
+ * @clip_cpus: cpumask of cpus where the frequency constraints will happen.
+ *
+ * This interface function registers the cpufreq cooling device with the name
+ * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq
+ * cooling devices.
+ *
+ * Return: a valid struct thermal_cooling_device pointer on success,
+ * on failure, it returns a corresponding ERR_PTR().
+ */
+struct thermal_cooling_device *
+cpufreq_cooling_register(const struct cpumask *clip_cpus)
+{
+ return __cpufreq_cooling_register(NULL, clip_cpus);
+}
EXPORT_SYMBOL_GPL(cpufreq_cooling_register);
/**
+ * of_cpufreq_cooling_register - function to create cpufreq cooling device.
+ * @np: a valid struct device_node to the cooling device device tree node
+ * @clip_cpus: cpumask of cpus where the frequency constraints will happen.
+ *
+ * This interface function registers the cpufreq cooling device with the name
+ * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq
+ * cooling devices. Using this API, the cpufreq cooling device will be
+ * linked to the device tree node provided.
+ *
+ * Return: a valid struct thermal_cooling_device pointer on success,
+ * on failure, it returns a corresponding ERR_PTR().
+ */
+struct thermal_cooling_device *
+of_cpufreq_cooling_register(struct device_node *np,
+ const struct cpumask *clip_cpus)
+{
+ if (!np)
+ return ERR_PTR(-EINVAL);
+
+ return __cpufreq_cooling_register(np, clip_cpus);
+}
+EXPORT_SYMBOL_GPL(of_cpufreq_cooling_register);
+
+/**
* cpufreq_cooling_unregister - function to remove cpufreq cooling device.
* @cdev: thermal cooling device pointer.
*
diff --git a/include/linux/cpu_cooling.h b/include/linux/cpu_cooling.h
index a5d52ee..c303d38 100644
--- a/include/linux/cpu_cooling.h
+++ b/include/linux/cpu_cooling.h
@@ -24,6 +24,7 @@
#ifndef __CPU_COOLING_H__
#define __CPU_COOLING_H__
+#include <linux/of.h>
#include <linux/thermal.h>
#include <linux/cpumask.h>
@@ -36,6 +37,24 @@ struct thermal_cooling_device *
cpufreq_cooling_register(const struct cpumask *clip_cpus);
/**
+ * of_cpufreq_cooling_register - create cpufreq cooling device based on DT.
+ * @np: a valid struct device_node to the cooling device device tree node.
+ * @clip_cpus: cpumask of cpus where the frequency constraints will happen
+ */
+#ifdef CONFIG_THERMAL_OF
+struct thermal_cooling_device *
+of_cpufreq_cooling_register(struct device_node *np,
+ const struct cpumask *clip_cpus);
+#else
+static inline struct thermal_cooling_device *
+of_cpufreq_cooling_register(struct device_node *np,
+ const struct cpumask *clip_cpus)
+{
+ return NULL;
+}
+#endif
+
+/**
* cpufreq_cooling_unregister - function to remove cpufreq cooling device.
* @cdev: thermal cooling device pointer.
*/
@@ -48,6 +67,12 @@ cpufreq_cooling_register(const struct cpumask *clip_cpus)
{
return NULL;
}
+static inline struct thermal_cooling_device *
+of_cpufreq_cooling_register(struct device_node *np,
+ const struct cpumask *clip_cpus)
+{
+ return NULL;
+}
static inline
void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
{
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 06/18] cpufreq: cpufreq-cpu0: add dt node parsing for cooling device properties
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (3 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 05/18] thermal: cpu_cooling: introduce of_cpufreq_cooling_register Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 07/18] hwmon: lm75: expose to thermal fw via DT nodes Eduardo Valentin
` (9 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Rafael J. Wysocki, Viresh Kumar,
cpufreq, devicetree-discuss
This patch changes the cpufreq-cpu0 driver to consider if
a cpu needs cooling (with cpufreq). In case the cooling is needed,
the cpu0 device tree node needs to be properly configured
with cooling device properties.
In case these properties are present,, the driver will
load a cpufreq cooling device in the system. The cpufreq-cpu0
driver is not interested in determining how the system should
be using the cooling device. The driver is responsible
only of loading the cooling device.
Describing how the cooling device will be used can be
accomplished by setting up a thermal zone that references
and is composed by the cpufreq cooling device.
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: cpufreq@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
.../devicetree/bindings/cpufreq/cpufreq-cpu0.txt | 7 +++++++
drivers/cpufreq/Kconfig | 2 +-
drivers/cpufreq/cpufreq-cpu0.c | 16 ++++++++++++++++
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
index 051f764..f055515 100644
--- a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
@@ -15,6 +15,10 @@ Optional properties:
- clock-latency: Specify the possible maximum transition latency for clock,
in unit of nanoseconds.
- voltage-tolerance: Specify the CPU voltage tolerance in percentage.
+- #cooling-cells:
+- cooling-min-level:
+- cooling-max-level:
+ Please refer to Documentation/devicetree/bindings/thermal/thermal.txt.
Examples:
@@ -33,6 +37,9 @@ cpus {
198000 850000
>;
clock-latency = <61036>; /* two CLK32 periods */
+ #cooling-cells = <2>;
+ cooling-min-level = <0>;
+ cooling-max-level = <2>;
};
cpu@1 {
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index 534fcb8..fc1e9a5 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -186,7 +186,7 @@ config CPU_FREQ_GOV_CONSERVATIVE
config GENERIC_CPUFREQ_CPU0
tristate "Generic CPU0 cpufreq driver"
- depends on HAVE_CLK && REGULATOR && PM_OPP && OF
+ depends on HAVE_CLK && REGULATOR && PM_OPP && OF && THERMAL && CPU_THERMAL
select CPU_FREQ_TABLE
help
This adds a generic cpufreq driver for CPU0 frequency management.
diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index 78c49d8..fd707b8 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -13,7 +13,9 @@
#include <linux/clk.h>
#include <linux/cpu.h>
+#include <linux/cpu_cooling.h>
#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -21,6 +23,7 @@
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
+#include <linux/thermal.h>
static unsigned int transition_latency;
static unsigned int voltage_tolerance; /* in percentage */
@@ -29,6 +32,7 @@ static struct device *cpu_dev;
static struct clk *cpu_clk;
static struct regulator *cpu_reg;
static struct cpufreq_frequency_table *freq_table;
+static struct thermal_cooling_device *cdev;
static int cpu0_verify_speed(struct cpufreq_policy *policy)
{
@@ -260,6 +264,17 @@ static int cpu0_cpufreq_probe(struct platform_device *pdev)
goto out_free_table;
}
+ /*
+ * For now, just loading the cooling device;
+ * thermal DT code takes care of matching them.
+ */
+ if (of_find_property(np, "#cooling-cells", NULL)) {
+ cdev = of_cpufreq_cooling_register(np, cpu_present_mask);
+ if (IS_ERR(cdev))
+ pr_err("running cpufreq without cooling device: %ld\n",
+ PTR_ERR(cdev));
+ }
+
of_node_put(np);
return 0;
@@ -272,6 +287,7 @@ out_put_node:
static int cpu0_cpufreq_remove(struct platform_device *pdev)
{
+ cpufreq_cooling_unregister(cdev);
cpufreq_unregister_driver(&cpu0_cpufreq_driver);
opp_free_cpufreq_table(cpu_dev, &freq_table);
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 07/18] hwmon: lm75: expose to thermal fw via DT nodes
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (4 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 06/18] cpufreq: cpufreq-cpu0: add dt node parsing for cooling device properties Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 09/18] thermal: ti-soc-thermal: use thermal DT infrastructure Eduardo Valentin
` (8 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Jean Delvare
This patch adds to lm75 temperature sensor the possibility
to expose itself as thermal zone device, registered on the
thermal framework.
The thermal zone is built only if a device tree node
describing a thermal zone for this sensor is present
inside the lm75 DT node. Otherwise, the driver behavior
will be the same.
Cc: Jean Delvare <khali@linux-fr.org>
Cc: lm-sensors@lm-sensors.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
drivers/hwmon/lm75.c | 35 ++++++++++++++++++++++++++++++-----
1 file changed, 30 insertions(+), 5 deletions(-)
diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index c03b490..1d3600a 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -27,6 +27,8 @@
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/thermal.h>
#include "lm75.h"
@@ -70,6 +72,7 @@ static const u8 LM75_REG_TEMP[3] = {
/* Each client has this additional data */
struct lm75_data {
struct device *hwmon_dev;
+ struct thermal_zone_device *tz;
struct mutex update_lock;
u8 orig_conf;
u8 resolution; /* In bits, between 9 and 12 */
@@ -90,22 +93,36 @@ static struct lm75_data *lm75_update_device(struct device *dev);
/*-----------------------------------------------------------------------*/
+static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
+{
+ return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
+}
+
/* sysfs attributes for hwmon */
+static int lm75_read_temp(void *dev, long *temp)
+{
+ struct lm75_data *data = lm75_update_device(dev);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ *temp = lm75_reg_to_mc(data->temp[0], data->resolution);
+
+ return 0;
+}
+
static ssize_t show_temp(struct device *dev, struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct lm75_data *data = lm75_update_device(dev);
- long temp;
if (IS_ERR(data))
return PTR_ERR(data);
- temp = ((data->temp[attr->index] >> (16 - data->resolution)) * 1000)
- >> (data->resolution - 8);
-
- return sprintf(buf, "%ld\n", temp);
+ return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index],
+ data->resolution));
}
static ssize_t set_temp(struct device *dev, struct device_attribute *da,
@@ -271,6 +288,13 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
goto exit_remove;
}
+ data->tz = thermal_zone_of_sensor_register(&client->dev,
+ 0,
+ &client->dev,
+ lm75_read_temp, NULL);
+ if (IS_ERR(data->tz))
+ data->tz = NULL;
+
dev_info(&client->dev, "%s: sensor '%s'\n",
dev_name(data->hwmon_dev), client->name);
@@ -285,6 +309,7 @@ static int lm75_remove(struct i2c_client *client)
{
struct lm75_data *data = i2c_get_clientdata(client);
+ thermal_zone_of_sensor_unregister(&client->dev, data->tz);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &lm75_group);
lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 09/18] thermal: ti-soc-thermal: use thermal DT infrastructure
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (5 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 07/18] hwmon: lm75: expose to thermal fw via DT nodes Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 10/18] arm: dts: add omap4 CPU thermal data Eduardo Valentin
` (7 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin
This patch improves the ti-soc-thermal driver by adding the
support to build the thermal zones based on DT nodes.
The driver will have two options now to build the thermal
zones. The first option is the zones originally coded
in this driver. So, the driver behavior will be same
if there is no DT node describing the zones. The second
option, when it is found a DT node with thermal data,
will used the common infrastructure to build the thermal
zone and bind its cooling devices.
In case the driver loads thermal data using the legacy
mode, this driver still adds to the system
a cpufreq cooling device. Loading the thermal data from
DT, the driver assumes someone else will add the cpufreq
cooling device, like the cpufreq driver.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 77 +++++++++++++++++-----
1 file changed, 62 insertions(+), 15 deletions(-)
diff --git a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
index 4f8b9af..b80b5b8 100644
--- a/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
+++ b/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
@@ -31,6 +31,7 @@
#include <linux/cpufreq.h>
#include <linux/cpumask.h>
#include <linux/cpu_cooling.h>
+#include <linux/of.h>
#include "ti-thermal.h"
#include "ti-bandgap.h"
@@ -44,6 +45,7 @@ struct ti_thermal_data {
enum thermal_device_mode mode;
struct work_struct thermal_wq;
int sensor_id;
+ bool our_zone;
};
static void ti_thermal_work(struct work_struct *work)
@@ -75,11 +77,10 @@ static inline int ti_thermal_hotspot_temperature(int t, int s, int c)
/* thermal zone ops */
/* Get temperature callback function for thermal zone*/
-static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
- unsigned long *temp)
+static inline int __ti_thermal_get_temp(void *devdata, long *temp)
{
struct thermal_zone_device *pcb_tz = NULL;
- struct ti_thermal_data *data = thermal->devdata;
+ struct ti_thermal_data *data = devdata;
struct ti_bandgap *bgp;
const struct ti_temp_sensor *s;
int ret, tmp, slope, constant;
@@ -117,6 +118,14 @@ static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
return ret;
}
+static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
+ unsigned long *temp)
+{
+ struct ti_thermal_data *data = thermal->devdata;
+
+ return __ti_thermal_get_temp(data, temp);
+}
+
/* Bind callback functions for thermal zone */
static int ti_thermal_bind(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev)
@@ -229,11 +238,9 @@ static int ti_thermal_get_trip_temp(struct thermal_zone_device *thermal,
return 0;
}
-/* Get the temperature trend callback functions for thermal zone */
-static int ti_thermal_get_trend(struct thermal_zone_device *thermal,
- int trip, enum thermal_trend *trend)
+static int __ti_thermal_get_trend(void *p, long *trend)
{
- struct ti_thermal_data *data = thermal->devdata;
+ struct ti_thermal_data *data = p;
struct ti_bandgap *bgp;
int id, tr, ret = 0;
@@ -244,6 +251,22 @@ static int ti_thermal_get_trend(struct thermal_zone_device *thermal,
if (ret)
return ret;
+ *trend = tr;
+
+ return 0;
+}
+
+/* Get the temperature trend callback functions for thermal zone */
+static int ti_thermal_get_trend(struct thermal_zone_device *thermal,
+ int trip, enum thermal_trend *trend)
+{
+ int ret;
+ long tr;
+
+ ret = __ti_thermal_get_trend(thermal->devdata, &tr);
+ if (ret)
+ return ret;
+
if (tr > 0)
*trend = THERMAL_TREND_RAISING;
else if (tr < 0)
@@ -307,16 +330,23 @@ int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id,
if (!data)
return -EINVAL;
- /* Create thermal zone */
- data->ti_thermal = thermal_zone_device_register(domain,
+ /* in case this is specified by DT */
+ data->ti_thermal = thermal_zone_of_sensor_register(bgp->dev, id,
+ data, __ti_thermal_get_temp,
+ __ti_thermal_get_trend);
+ if (IS_ERR(data->ti_thermal)) {
+ /* Create thermal zone */
+ data->ti_thermal = thermal_zone_device_register(domain,
OMAP_TRIP_NUMBER, 0, data, &ti_thermal_ops,
NULL, FAST_TEMP_MONITORING_RATE,
FAST_TEMP_MONITORING_RATE);
- if (IS_ERR(data->ti_thermal)) {
- dev_err(bgp->dev, "thermal zone device is NULL\n");
- return PTR_ERR(data->ti_thermal);
+ if (IS_ERR(data->ti_thermal)) {
+ dev_err(bgp->dev, "thermal zone device is NULL\n");
+ return PTR_ERR(data->ti_thermal);
+ }
+ data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE;
+ data->our_zone = true;
}
- data->ti_thermal->polling_delay = FAST_TEMP_MONITORING_RATE;
ti_bandgap_set_sensor_data(bgp, id, data);
ti_bandgap_write_update_interval(bgp, data->sensor_id,
data->ti_thermal->polling_delay);
@@ -330,7 +360,13 @@ int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id)
data = ti_bandgap_get_sensor_data(bgp, id);
- thermal_zone_device_unregister(data->ti_thermal);
+ if (data && data->ti_thermal) {
+ if (data->our_zone)
+ thermal_zone_device_unregister(data->ti_thermal);
+ else
+ thermal_zone_of_sensor_unregister(bgp->dev,
+ data->ti_thermal);
+ }
return 0;
}
@@ -349,6 +385,15 @@ int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id)
int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id)
{
struct ti_thermal_data *data;
+ struct device_node *np = bgp->dev->of_node;
+
+ /*
+ * We are assuming here that if one deploys the zone
+ * using DT, then it must be aware that the cooling device
+ * loading has to happen via cpufreq driver.
+ */
+ if (of_find_property(np, "#thermal-sensor-cells", NULL))
+ return 0;
data = ti_bandgap_get_sensor_data(bgp, id);
if (!data || IS_ERR(data))
@@ -379,7 +424,9 @@ int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id)
struct ti_thermal_data *data;
data = ti_bandgap_get_sensor_data(bgp, id);
- cpufreq_cooling_unregister(data->cool_dev);
+
+ if (data && data->cool_dev)
+ cpufreq_cooling_unregister(data->cool_dev);
return 0;
}
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 10/18] arm: dts: add omap4 CPU thermal data
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (6 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 09/18] thermal: ti-soc-thermal: use thermal DT infrastructure Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 11/18] arm: dts: add omap4430 " Eduardo Valentin
` (6 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: devicetree, durgadoss.r, linux-pm, Tony Lindgren, linux-kernel,
lm-sensors, Eduardo Valentin, Benoît Cousson, grant.likely,
Russell King, linux-omap, linux-arm-kernel
This patch changes a dtsi file to contain the thermal data
for MPU domain on OMAP4 and later SoCs. This data will
enable the passive cooling with CPUfreq cooling device
at 100C and the system will do a thermal shutdown at 125C.
This thermal data can be reused across TI SoC devices.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap4-cpu-thermal.dtsi | 41 ++++++++++++++++++++++++++++++++
1 file changed, 41 insertions(+)
create mode 100644 arch/arm/boot/dts/omap4-cpu-thermal.dtsi
diff --git a/arch/arm/boot/dts/omap4-cpu-thermal.dtsi b/arch/arm/boot/dts/omap4-cpu-thermal.dtsi
new file mode 100644
index 0000000..65a6deb
--- /dev/null
+++ b/arch/arm/boot/dts/omap4-cpu-thermal.dtsi
@@ -0,0 +1,41 @@
+/*
+ * Device Tree Source for OMAP4/5 SoC CPU thermal
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
+ * Contact: Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <dt-bindings/thermal/thermal.h>
+
+cpu_thermal: cpu_thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap 0>;
+
+ trips {
+ cpu_alert0: cpu_alert {
+ temperature = <100000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_PASSIVE;
+ };
+ cpu_crit: cpu_crit {
+ temperature = <125000>; /* millicelsius */
+ hysteresis = <2000>; /* millicelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&cpu_alert0>;
+ cooling-device =
+ <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+ };
+ };
+};
--
1.8.2.1.342.gfa7285d
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 11/18] arm: dts: add omap4430 thermal data
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (7 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 10/18] arm: dts: add omap4 CPU thermal data Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 12:24 ` Nishanth Menon
2013-09-27 3:13 ` [PATCHv4 12/18] arm: dts: add omap4460 " Eduardo Valentin
` (5 subsequent siblings)
14 siblings, 1 reply; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: devicetree, durgadoss.r, linux-pm, Tony Lindgren,
devicetree-discuss, linux-kernel, lm-sensors, Eduardo Valentin,
Benoît Cousson, grant.likely, Russell King, linux-omap,
linux-arm-kernel
This patch changes the dtsi entry on omap4430 to contain
the thermal data. This data will enable the passive
cooling with CPUfreq cooling device at 100C and the
system will do a thermal shutdown at 125C.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap443x.dtsi | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
index bcf455e..e9c97d6 100644
--- a/arch/arm/boot/dts/omap443x.dtsi
+++ b/arch/arm/boot/dts/omap443x.dtsi
@@ -12,7 +12,7 @@
/ {
cpus {
- cpu@0 {
+ cpu0: cpu@0 {
/* OMAP443x variants OPP50-OPPNT */
operating-points = <
/* kHz uV */
@@ -25,9 +25,15 @@
};
};
- bandgap {
+ thermal-zones{
+ #include "omap4-cpu-thermal.dtsi"
+ };
+
+ bandgap: bandgap {
reg = <0x4a002260 0x4
0x4a00232C 0x4>;
compatible = "ti,omap4430-bandgap";
+
+ #thermal-sensor-cells = <0>;
};
};
--
1.8.2.1.342.gfa7285d
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 31+ messages in thread* Re: [PATCHv4 11/18] arm: dts: add omap4430 thermal data
2013-09-27 3:13 ` [PATCHv4 11/18] arm: dts: add omap4430 " Eduardo Valentin
@ 2013-09-27 12:24 ` Nishanth Menon
2013-09-27 13:20 ` Eduardo Valentin
0 siblings, 1 reply; 31+ messages in thread
From: Nishanth Menon @ 2013-09-27 12:24 UTC (permalink / raw)
To: Eduardo Valentin
Cc: mark.rutland, devicetree, wni, durgadoss.r, ian.campbell,
pawel.moll, swarren, Tony Lindgren, devicetree-discuss, linux-pm,
linux-kernel, rob.herring, lm-sensors, linux-arm-kernel,
Benoît Cousson, grant.likely, Russell King, rui.zhang,
linux-omap, linux
On 23:13-20130926, Eduardo Valentin wrote:
> This patch changes the dtsi entry on omap4430 to contain
> the thermal data. This data will enable the passive
> cooling with CPUfreq cooling device at 100C and the
> system will do a thermal shutdown at 125C.
>
> Cc: "Benoît Cousson" <bcousson@baylibre.com>
> Cc: Tony Lindgren <tony@atomide.com>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: linux-omap@vger.kernel.org
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
> ---
> arch/arm/boot/dts/omap443x.dtsi | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
> index bcf455e..e9c97d6 100644
> --- a/arch/arm/boot/dts/omap443x.dtsi
> +++ b/arch/arm/boot/dts/omap443x.dtsi
> @@ -12,7 +12,7 @@
>
> / {
> cpus {
> - cpu@0 {
> + cpu0: cpu@0 {
> /* OMAP443x variants OPP50-OPPNT */
> operating-points = <
> /* kHz uV */
> @@ -25,9 +25,15 @@
> };
> };
>
> - bandgap {
> + thermal-zones{
> + #include "omap4-cpu-thermal.dtsi"
> + };
> +
> + bandgap: bandgap {
> reg = <0x4a002260 0x4
> 0x4a00232C 0x4>;
> compatible = "ti,omap4430-bandgap";
> +
> + #thermal-sensor-cells = <0>;
2 cents:
we might want to move bandgap under ocp?
> };
> };
> --
> 1.8.2.1.342.gfa7285d
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
--
Regards,
Nishanth Menon
^ permalink raw reply [flat|nested] 31+ messages in thread* Re: [PATCHv4 11/18] arm: dts: add omap4430 thermal data
2013-09-27 12:24 ` Nishanth Menon
@ 2013-09-27 13:20 ` Eduardo Valentin
2013-09-27 13:26 ` Nishanth Menon
0 siblings, 1 reply; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 13:20 UTC (permalink / raw)
To: Nishanth Menon
Cc: mark.rutland, devicetree, wni, durgadoss.r, ian.campbell,
pawel.moll, swarren, Tony Lindgren, devicetree-discuss, linux-pm,
linux-kernel, rob.herring, lm-sensors, Eduardo Valentin,
linux-arm-kernel, Benoît Cousson, grant.likely, Russell King,
rui.zhang, linux-omap, linux
[-- Attachment #1.1: Type: text/plain, Size: 2008 bytes --]
On 27-09-2013 08:24, Nishanth Menon wrote:
> On 23:13-20130926, Eduardo Valentin wrote:
>> This patch changes the dtsi entry on omap4430 to contain
>> the thermal data. This data will enable the passive
>> cooling with CPUfreq cooling device at 100C and the
>> system will do a thermal shutdown at 125C.
>>
>> Cc: "Benoît Cousson" <bcousson@baylibre.com>
>> Cc: Tony Lindgren <tony@atomide.com>
>> Cc: Russell King <linux@arm.linux.org.uk>
>> Cc: linux-omap@vger.kernel.org
>> Cc: devicetree-discuss@lists.ozlabs.org
>> Cc: linux-arm-kernel@lists.infradead.org
>> Cc: linux-kernel@vger.kernel.org
>> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
>> ---
>> arch/arm/boot/dts/omap443x.dtsi | 10 ++++++++--
>> 1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
>> index bcf455e..e9c97d6 100644
>> --- a/arch/arm/boot/dts/omap443x.dtsi
>> +++ b/arch/arm/boot/dts/omap443x.dtsi
>> @@ -12,7 +12,7 @@
>>
>> / {
>> cpus {
>> - cpu@0 {
>> + cpu0: cpu@0 {
>> /* OMAP443x variants OPP50-OPPNT */
>> operating-points = <
>> /* kHz uV */
>> @@ -25,9 +25,15 @@
>> };
>> };
>>
>> - bandgap {
>> + thermal-zones{
>> + #include "omap4-cpu-thermal.dtsi"
>> + };
>> +
>> + bandgap: bandgap {
>> reg = <0x4a002260 0x4
>> 0x4a00232C 0x4>;
>> compatible = "ti,omap4430-bandgap";
>> +
>> + #thermal-sensor-cells = <0>;
> 2 cents:
> we might want to move bandgap under ocp?
>
Yes, agreed. But I don't think this change is related to this patch or
to this series.
Tks Nishanth
>> };
>> };
>> --
>> 1.8.2.1.342.gfa7285d
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
[-- Attachment #1.2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 295 bytes --]
[-- Attachment #2: Type: text/plain, Size: 176 bytes --]
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 31+ messages in thread* Re: [PATCHv4 11/18] arm: dts: add omap4430 thermal data
2013-09-27 13:20 ` Eduardo Valentin
@ 2013-09-27 13:26 ` Nishanth Menon
2013-09-27 13:42 ` Eduardo Valentin
0 siblings, 1 reply; 31+ messages in thread
From: Nishanth Menon @ 2013-09-27 13:26 UTC (permalink / raw)
To: Eduardo Valentin
Cc: Mark Rutland, dt list, wni, durgadoss.r, Ian Campbell, Pawel Moll,
Stephen Warren, Tony Lindgren, devicetree-discuss, linux-pm, lkml,
Rob Herring, lm-sensors, linux-arm-kernel@lists.infradead.org,
Benoît Cousson, Grant Likely, Russell King, rui.zhang,
linux-omap, linux
On Fri, Sep 27, 2013 at 8:20 AM, Eduardo Valentin
<eduardo.valentin@ti.com> wrote:
> On 27-09-2013 08:24, Nishanth Menon wrote:
>> On 23:13-20130926, Eduardo Valentin wrote:
>>> This patch changes the dtsi entry on omap4430 to contain
>>> the thermal data. This data will enable the passive
>>> cooling with CPUfreq cooling device at 100C and the
>>> system will do a thermal shutdown at 125C.
>>>
>>> Cc: "Benoît Cousson" <bcousson@baylibre.com>
>>> Cc: Tony Lindgren <tony@atomide.com>
>>> Cc: Russell King <linux@arm.linux.org.uk>
>>> Cc: linux-omap@vger.kernel.org
>>> Cc: devicetree-discuss@lists.ozlabs.org
>>> Cc: linux-arm-kernel@lists.infradead.org
>>> Cc: linux-kernel@vger.kernel.org
>>> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
>>> ---
>>> arch/arm/boot/dts/omap443x.dtsi | 10 ++++++++--
>>> 1 file changed, 8 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
>>> index bcf455e..e9c97d6 100644
>>> --- a/arch/arm/boot/dts/omap443x.dtsi
>>> +++ b/arch/arm/boot/dts/omap443x.dtsi
>>> @@ -12,7 +12,7 @@
>>>
>>> / {
>>> cpus {
>>> - cpu@0 {
>>> + cpu0: cpu@0 {
>>> /* OMAP443x variants OPP50-OPPNT */
>>> operating-points = <
>>> /* kHz uV */
>>> @@ -25,9 +25,15 @@
>>> };
>>> };
>>>
>>> - bandgap {
>>> + thermal-zones{
>>> + #include "omap4-cpu-thermal.dtsi"
>>> + };
>>> +
>>> + bandgap: bandgap {
>>> reg = <0x4a002260 0x4
>>> 0x4a00232C 0x4>;
>>> compatible = "ti,omap4430-bandgap";
>>> +
>>> + #thermal-sensor-cells = <0>;
>> 2 cents:
>> we might want to move bandgap under ocp?
>>
>
> Yes, agreed. But I don't think this change is related to this patch or
> to this series.
Correct - this comment is not related to the current patch, hence my 2
cents ;) - will be nice to have it cleaned up though..
Regards,
Nishanth Menon
^ permalink raw reply [flat|nested] 31+ messages in thread* Re: [PATCHv4 11/18] arm: dts: add omap4430 thermal data
2013-09-27 13:26 ` Nishanth Menon
@ 2013-09-27 13:42 ` Eduardo Valentin
0 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 13:42 UTC (permalink / raw)
To: Nishanth Menon
Cc: Mark Rutland, dt list, wni, durgadoss.r, Ian Campbell, Pawel Moll,
Stephen Warren, Tony Lindgren, devicetree-discuss, linux-pm, lkml,
Rob Herring, lm-sensors, Eduardo Valentin, linux,
Benoît Cousson, Grant Likely, Russell King, rui.zhang,
linux-omap, linux-arm-kernel@lists.infradead.org
[-- Attachment #1.1: Type: text/plain, Size: 2346 bytes --]
On 27-09-2013 09:26, Nishanth Menon wrote:
> On Fri, Sep 27, 2013 at 8:20 AM, Eduardo Valentin
> <eduardo.valentin@ti.com> wrote:
>> On 27-09-2013 08:24, Nishanth Menon wrote:
>>> On 23:13-20130926, Eduardo Valentin wrote:
>>>> This patch changes the dtsi entry on omap4430 to contain
>>>> the thermal data. This data will enable the passive
>>>> cooling with CPUfreq cooling device at 100C and the
>>>> system will do a thermal shutdown at 125C.
>>>>
>>>> Cc: "Benoît Cousson" <bcousson@baylibre.com>
>>>> Cc: Tony Lindgren <tony@atomide.com>
>>>> Cc: Russell King <linux@arm.linux.org.uk>
>>>> Cc: linux-omap@vger.kernel.org
>>>> Cc: devicetree-discuss@lists.ozlabs.org
>>>> Cc: linux-arm-kernel@lists.infradead.org
>>>> Cc: linux-kernel@vger.kernel.org
>>>> Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
>>>> ---
>>>> arch/arm/boot/dts/omap443x.dtsi | 10 ++++++++--
>>>> 1 file changed, 8 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
>>>> index bcf455e..e9c97d6 100644
>>>> --- a/arch/arm/boot/dts/omap443x.dtsi
>>>> +++ b/arch/arm/boot/dts/omap443x.dtsi
>>>> @@ -12,7 +12,7 @@
>>>>
>>>> / {
>>>> cpus {
>>>> - cpu@0 {
>>>> + cpu0: cpu@0 {
>>>> /* OMAP443x variants OPP50-OPPNT */
>>>> operating-points = <
>>>> /* kHz uV */
>>>> @@ -25,9 +25,15 @@
>>>> };
>>>> };
>>>>
>>>> - bandgap {
>>>> + thermal-zones{
>>>> + #include "omap4-cpu-thermal.dtsi"
>>>> + };
>>>> +
>>>> + bandgap: bandgap {
>>>> reg = <0x4a002260 0x4
>>>> 0x4a00232C 0x4>;
>>>> compatible = "ti,omap4430-bandgap";
>>>> +
>>>> + #thermal-sensor-cells = <0>;
>>> 2 cents:
>>> we might want to move bandgap under ocp?
>>>
>>
>> Yes, agreed. But I don't think this change is related to this patch or
>> to this series.
>
> Correct - this comment is not related to the current patch, hence my 2
> cents ;) - will be nice to have it cleaned up though..
Yes, it will be cleaned. ;-) Tks.
>
> Regards,
> Nishanth Menon
>
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
[-- Attachment #1.2: OpenPGP digital signature --]
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[-- Attachment #2: Type: text/plain, Size: 176 bytes --]
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 31+ messages in thread
* [PATCHv4 12/18] arm: dts: add omap4460 thermal data
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (8 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 11/18] arm: dts: add omap4430 " Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 14/18] arm: dts: add cooling properties on omap4460 cpu node Eduardo Valentin
` (4 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Benoît Cousson,
Tony Lindgren, Russell King, linux-omap, linux-arm-kernel
This patch changes the dtsi entry on omap4460 to contain
the thermal data. This data will enable the passive
cooling with CPUfreq cooling device at 100C and the
system will do a thermal shutdown at 125C.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap4460.dtsi | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/omap4460.dtsi b/arch/arm/boot/dts/omap4460.dtsi
index c2f0f39..4d93aba 100644
--- a/arch/arm/boot/dts/omap4460.dtsi
+++ b/arch/arm/boot/dts/omap4460.dtsi
@@ -12,7 +12,7 @@
/ {
cpus {
/* OMAP446x 'standard device' variants OPP50 to OPPTurbo */
- cpu@0 {
+ cpu0: cpu@0 {
operating-points = <
/* kHz uV */
350000 1025000
@@ -30,12 +30,18 @@
ti,hwmods = "debugss";
};
- bandgap {
+ thermal-zones{
+ #include "omap4-cpu-thermal.dtsi"
+ };
+
+ bandgap: bandgap {
reg = <0x4a002260 0x4
0x4a00232C 0x4
0x4a002378 0x18>;
compatible = "ti,omap4460-bandgap";
interrupts = <0 126 IRQ_TYPE_LEVEL_HIGH>; /* talert */
gpios = <&gpio3 22 0>; /* tshut */
+
+ #thermal-sensor-cells = <0>;
};
};
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 14/18] arm: dts: add cooling properties on omap4460 cpu node
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (9 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 12/18] arm: dts: add omap4460 " Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 15/18] arm: dts: add omap5 GPU thermal data Eduardo Valentin
` (3 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Benoît Cousson,
Tony Lindgren, Russell King, linux-omap, linux-arm-kernel
OMAP4460 devices can reach high temperatures and thus
needs to have cpufreq-cooling on systems running on it.
This patch adds the required cooling device properties
so that cpufreq-cpu0 driver loads the cooling device.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap4460.dtsi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/omap4460.dtsi b/arch/arm/boot/dts/omap4460.dtsi
index 4d93aba..dc22719 100644
--- a/arch/arm/boot/dts/omap4460.dtsi
+++ b/arch/arm/boot/dts/omap4460.dtsi
@@ -20,6 +20,11 @@
920000 1313000
>;
clock-latency = <300000>; /* From legacy driver */
+
+ /* cooling options */
+ cooling-min-level = <0>;
+ cooling-max-level = <2>;
+ #cooling-cells = <2>; /* min followed by max */
};
};
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 15/18] arm: dts: add omap5 GPU thermal data
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (10 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 14/18] arm: dts: add cooling properties on omap4460 cpu node Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 16/18] arm: dts: add omap5 CORE " Eduardo Valentin
` (2 subsequent siblings)
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Benoît Cousson,
Tony Lindgren, Russell King, linux-omap, linux-arm-kernel
This patch changes a dtsi file to contain the thermal data
for GPU domain on OMAP5 and later SoCs. This data will
enable a thermal shutdown at 125C.
This thermal data can be reused across TI SoC devices.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap5-gpu-thermal.dtsi | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
create mode 100644 arch/arm/boot/dts/omap5-gpu-thermal.dtsi
diff --git a/arch/arm/boot/dts/omap5-gpu-thermal.dtsi b/arch/arm/boot/dts/omap5-gpu-thermal.dtsi
new file mode 100644
index 0000000..8941c8e
--- /dev/null
+++ b/arch/arm/boot/dts/omap5-gpu-thermal.dtsi
@@ -0,0 +1,28 @@
+/*
+ * Device Tree Source for OMAP543x SoC GPU thermal
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
+ * Contact: Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <dt-bindings/thermal/thermal.h>
+
+gpu_thermal: gpu_thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap 1>;
+
+ trips {
+ gpu_crit: gpu_crit {
+ temperature = <125000>; /* milliCelsius */
+ hysteresis = <2000>; /* milliCelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+};
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 16/18] arm: dts: add omap5 CORE thermal data
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (11 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 15/18] arm: dts: add omap5 GPU thermal data Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
2013-09-27 3:15 ` [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni
Cc: grant.likely, durgadoss.r, linux-pm, devicetree, lm-sensors,
linux-kernel, Eduardo Valentin, Benoît Cousson,
Tony Lindgren, Russell King, linux-omap, linux-arm-kernel
This patch changes a dtsi file to contain the thermal data
for CORE domain on OMAP5 and later SoCs. This data will
enable a thermal shutdown at 125C.
This thermal data can be reused across TI SoC devices.
Cc: "Benoît Cousson" <bcousson@baylibre.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-omap@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
---
arch/arm/boot/dts/omap5-core-thermal.dtsi | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
create mode 100644 arch/arm/boot/dts/omap5-core-thermal.dtsi
diff --git a/arch/arm/boot/dts/omap5-core-thermal.dtsi b/arch/arm/boot/dts/omap5-core-thermal.dtsi
new file mode 100644
index 0000000..3e9dc00
--- /dev/null
+++ b/arch/arm/boot/dts/omap5-core-thermal.dtsi
@@ -0,0 +1,28 @@
+/*
+ * Device Tree Source for OMAP543x SoC CORE thermal
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
+ * Contact: Eduardo Valentin <eduardo.valentin@ti.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <dt-bindings/thermal/thermal.h>
+
+core_thermal: core_thermal {
+ polling-delay-passive = <250>; /* milliseconds */
+ polling-delay = <1000>; /* milliseconds */
+
+ /* sensor ID */
+ thermal-sensors = <&bandgap 2>;
+
+ trips {
+ core_crit: core_crit {
+ temperature = <125000>; /* milliCelsius */
+ hysteresis = <2000>; /* milliCelsius */
+ type = THERMAL_TRIP_CRITICAL;
+ };
+ };
+};
--
1.8.2.1.342.gfa7285d
^ permalink raw reply related [flat|nested] 31+ messages in thread[parent not found: <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>]
* [PATCHv4 04/18] thermal: core: introduce thermal_of_cooling_device_register
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 08/18] hwmon: tmp102: expose to thermal fw via DT nodes Eduardo Valentin
` (3 subsequent siblings)
4 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin
This patch adds a new API to allow registering cooling devices
in the thermal framework derived from device tree nodes.
This API links the cooling device with the device tree node
so that binding with thermal zones is possible, given
that thermal zones are pointing to cooling device
device tree nodes.
Cc: Zhang Rui <rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
drivers/thermal/thermal_core.c | 58 +++++++++++++++++++++++++++++++++++++++---
include/linux/thermal.h | 4 +++
2 files changed, 58 insertions(+), 4 deletions(-)
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index fec3351..5325fee 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -34,6 +34,7 @@
#include <linux/thermal.h>
#include <linux/reboot.h>
#include <linux/string.h>
+#include <linux/of.h>
#include <net/netlink.h>
#include <net/genetlink.h>
@@ -1053,7 +1054,8 @@ static struct class thermal_class = {
};
/**
- * thermal_cooling_device_register() - register a new thermal cooling device
+ * __thermal_cooling_device_register() - register a new thermal cooling device
+ * @np: a pointer to a device tree node.
* @type: the thermal cooling device type.
* @devdata: device private data.
* @ops: standard thermal cooling devices callbacks.
@@ -1061,13 +1063,16 @@ static struct class thermal_class = {
* This interface function adds a new thermal cooling device (fan/processor/...)
* to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
* to all the thermal zone devices registered at the same time.
+ * It also gives the opportunity to link the cooling device to a device tree
+ * node, so that it can be bound to a thermal zone created out of device tree.
*
* Return: a pointer to the created struct thermal_cooling_device or an
* ERR_PTR. Caller must check return value with IS_ERR*() helpers.
*/
-struct thermal_cooling_device *
-thermal_cooling_device_register(char *type, void *devdata,
- const struct thermal_cooling_device_ops *ops)
+static struct thermal_cooling_device *
+__thermal_cooling_device_register(struct device_node *np,
+ char *type, void *devdata,
+ const struct thermal_cooling_device_ops *ops)
{
struct thermal_cooling_device *cdev;
int result;
@@ -1092,6 +1097,7 @@ thermal_cooling_device_register(char *type, void *devdata,
strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
mutex_init(&cdev->lock);
INIT_LIST_HEAD(&cdev->thermal_instances);
+ cdev->np = np;
cdev->ops = ops;
cdev->updated = true;
cdev->device.class = &thermal_class;
@@ -1134,9 +1140,53 @@ unregister:
device_unregister(&cdev->device);
return ERR_PTR(result);
}
+
+/**
+ * thermal_cooling_device_register() - register a new thermal cooling device
+ * @type: the thermal cooling device type.
+ * @devdata: device private data.
+ * @ops: standard thermal cooling devices callbacks.
+ *
+ * This interface function adds a new thermal cooling device (fan/processor/...)
+ * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
+ * to all the thermal zone devices registered at the same time.
+ *
+ * Return: a pointer to the created struct thermal_cooling_device or an
+ * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
+ */
+struct thermal_cooling_device *
+thermal_cooling_device_register(char *type, void *devdata,
+ const struct thermal_cooling_device_ops *ops)
+{
+ return __thermal_cooling_device_register(NULL, type, devdata, ops);
+}
EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
/**
+ * thermal_of_cooling_device_register() - register an OF thermal cooling device
+ * @np: a pointer to a device tree node.
+ * @type: the thermal cooling device type.
+ * @devdata: device private data.
+ * @ops: standard thermal cooling devices callbacks.
+ *
+ * This function will register a cooling device with device tree node reference.
+ * This interface function adds a new thermal cooling device (fan/processor/...)
+ * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
+ * to all the thermal zone devices registered at the same time.
+ *
+ * Return: a pointer to the created struct thermal_cooling_device or an
+ * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
+ */
+struct thermal_cooling_device *
+thermal_of_cooling_device_register(struct device_node *np,
+ char *type, void *devdata,
+ const struct thermal_cooling_device_ops *ops)
+{
+ return __thermal_cooling_device_register(np, type, devdata, ops);
+}
+EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
+
+/**
* thermal_cooling_device_unregister - removes the registered thermal cooling device
* @cdev: the thermal cooling device to remove.
*
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index b780c5b..f7e11c7 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -25,6 +25,7 @@
#ifndef __THERMAL_H__
#define __THERMAL_H__
+#include <linux/of.h>
#include <linux/idr.h>
#include <linux/device.h>
#include <linux/workqueue.h>
@@ -280,6 +281,9 @@ void thermal_zone_device_update(struct thermal_zone_device *);
struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
const struct thermal_cooling_device_ops *);
+struct thermal_cooling_device *
+thermal_of_cooling_device_register(struct device_node *np, char *, void *,
+ const struct thermal_cooling_device_ops *);
void thermal_cooling_device_unregister(struct thermal_cooling_device *);
struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp);
--
1.8.2.1.342.gfa7285d
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^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 08/18] hwmon: tmp102: expose to thermal fw via DT nodes
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
2013-09-27 3:13 ` [PATCHv4 04/18] thermal: core: introduce thermal_of_cooling_device_register Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 13/18] arm: dts: add cooling properties on omap4430 cpu node Eduardo Valentin
` (2 subsequent siblings)
4 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin,
Jean Delvare
This patch adds to tmp102 temperature sensor the possibility
to expose itself as thermal zone device, registered on the
thermal framework.
The thermal zone is built only if a device tree node
describing a thermal zone for this sensor is present
inside the tmp102 DT node. Otherwise, the driver behavior
will be the same.
Cc: Jean Delvare <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
Cc: lm-sensors-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Acked-by: Guenter Roeck <linux-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
drivers/hwmon/tmp102.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c
index d7b47ab..6748b45 100644
--- a/drivers/hwmon/tmp102.c
+++ b/drivers/hwmon/tmp102.c
@@ -27,6 +27,8 @@
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/jiffies.h>
+#include <linux/thermal.h>
+#include <linux/of.h>
#define DRIVER_NAME "tmp102"
@@ -50,6 +52,7 @@
struct tmp102 {
struct device *hwmon_dev;
+ struct thermal_zone_device *tz;
struct mutex lock;
u16 config_orig;
unsigned long last_update;
@@ -93,6 +96,15 @@ static struct tmp102 *tmp102_update_device(struct i2c_client *client)
return tmp102;
}
+static int tmp102_read_temp(void *dev, long *temp)
+{
+ struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
+
+ *temp = tmp102->temp[0];
+
+ return 0;
+}
+
static ssize_t tmp102_show_temp(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -204,6 +216,12 @@ static int tmp102_probe(struct i2c_client *client,
goto fail_remove_sysfs;
}
+ tmp102->tz = thermal_zone_of_sensor_register(&client->dev, 0,
+ &client->dev,
+ tmp102_read_temp, NULL);
+ if (IS_ERR(tmp102->tz))
+ tmp102->tz = NULL;
+
dev_info(&client->dev, "initialized\n");
return 0;
@@ -220,6 +238,7 @@ static int tmp102_remove(struct i2c_client *client)
{
struct tmp102 *tmp102 = i2c_get_clientdata(client);
+ thermal_zone_of_sensor_unregister(&client->dev, tmp102->tz);
hwmon_device_unregister(tmp102->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
--
1.8.2.1.342.gfa7285d
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^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 13/18] arm: dts: add cooling properties on omap4430 cpu node
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
2013-09-27 3:13 ` [PATCHv4 04/18] thermal: core: introduce thermal_of_cooling_device_register Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 08/18] hwmon: tmp102: expose to thermal fw via DT nodes Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 17/18] arm: dts: add omap5 thermal data Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 18/18] arm: dts: add cooling properties on omap5 cpu node Eduardo Valentin
4 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin,
Benoît Cousson, Tony Lindgren, Russell King,
linux-omap-u79uwXL29TY76Z2rM5mHXA,
devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
OMAP4430 devices can reach high temperatures and thus
needs to have cpufreq-cooling on systems running on it.
This patch adds the required cooling device properties
so that cpufreq-cpu0 driver loads the cooling device.
Cc: "Benoît Cousson" <bcousson-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>
Cc: Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org
Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
arch/arm/boot/dts/omap443x.dtsi | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/omap443x.dtsi b/arch/arm/boot/dts/omap443x.dtsi
index e9c97d6..930ab47 100644
--- a/arch/arm/boot/dts/omap443x.dtsi
+++ b/arch/arm/boot/dts/omap443x.dtsi
@@ -22,6 +22,11 @@
1008000 1375000
>;
clock-latency = <300000>; /* From legacy driver */
+
+ /* cooling options */
+ cooling-min-level = <0>;
+ cooling-max-level = <3>;
+ #cooling-cells = <2>; /* min followed by max */
};
};
--
1.8.2.1.342.gfa7285d
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^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 17/18] arm: dts: add omap5 thermal data
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
` (2 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 13/18] arm: dts: add cooling properties on omap4430 cpu node Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
2013-09-27 3:13 ` [PATCHv4 18/18] arm: dts: add cooling properties on omap5 cpu node Eduardo Valentin
4 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin,
Benoît Cousson, Tony Lindgren, Russell King,
linux-omap-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
This patch changes the dtsi entry on omap5 to contain
the thermal data. This data will enable the passive
cooling with CPUfreq cooling device at 100C. The
system will do a thermal shutdown at 125C whenever
any of its sensors sees this level.
Cc: "Benoît Cousson" <bcousson-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>
Cc: Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>
Cc: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
Cc: Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>
Cc: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
Cc: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
Cc: Ian Campbell <ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
arch/arm/boot/dts/omap5.dtsi | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/arch/arm/boot/dts/omap5.dtsi b/arch/arm/boot/dts/omap5.dtsi
index 7cdea1b..187cb71 100644
--- a/arch/arm/boot/dts/omap5.dtsi
+++ b/arch/arm/boot/dts/omap5.dtsi
@@ -33,7 +33,7 @@
#address-cells = <1>;
#size-cells = <0>;
- cpu@0 {
+ cpu0: cpu@0 {
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x0>;
@@ -45,6 +45,12 @@
};
};
+ thermal-zones {
+ #include "omap4-cpu-thermal.dtsi"
+ #include "omap5-gpu-thermal.dtsi"
+ #include "omap5-core-thermal.dtsi"
+ };
+
timer {
compatible = "arm,armv7-timer";
/* PPI secure/nonsecure IRQ */
@@ -705,13 +711,15 @@
};
};
- bandgap@4a0021e0 {
+ bandgap: bandgap@4a0021e0 {
reg = <0x4a0021e0 0xc
0x4a00232c 0xc
0x4a002380 0x2c
0x4a0023C0 0x3c>;
interrupts = <GIC_SPI 126 IRQ_TYPE_LEVEL_HIGH>;
compatible = "ti,omap5430-bandgap";
+
+ #thermal-sensor-cells = <1>;
};
};
};
--
1.8.2.1.342.gfa7285d
--
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^ permalink raw reply related [flat|nested] 31+ messages in thread* [PATCHv4 18/18] arm: dts: add cooling properties on omap5 cpu node
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
` (3 preceding siblings ...)
2013-09-27 3:13 ` [PATCHv4 17/18] arm: dts: add omap5 thermal data Eduardo Valentin
@ 2013-09-27 3:13 ` Eduardo Valentin
4 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:13 UTC (permalink / raw)
To: swarren-3lzwWm7+Weoh9ZMKESR00Q, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA,
rob.herring-bsGFqQB8/DxBDgjK7y7TUQ, linux-0h96xk9xTtrk1uMJSBkQmQ,
rui.zhang-ral2JQCrhuEAvxtiuMwx3w, wni-DDmLM1+adcrQT0dZR+AlfA
Cc: grant.likely-QSEj5FYQhm4dnm+yROfE0A,
durgadoss.r-ral2JQCrhuEAvxtiuMwx3w,
linux-pm-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
lm-sensors-GZX6beZjE8VD60Wz+7aTrA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Eduardo Valentin,
Benoît Cousson, Tony Lindgren, Russell King,
linux-omap-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
OMAP5 devices can reach high temperatures and thus
needs to have cpufreq-cooling on systems running on it.
This patch adds the required cooling device properties
so that cpufreq-cpu0 driver loads the cooling device.
Cc: "Benoît Cousson" <bcousson-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>
Cc: Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>
Cc: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
Cc: Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>
Cc: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
Cc: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
Cc: Ian Campbell <ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org>
Cc: Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>
Cc: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Signed-off-by: Eduardo Valentin <eduardo.valentin-l0cyMroinI0@public.gmane.org>
---
arch/arm/boot/dts/omap5.dtsi | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/arm/boot/dts/omap5.dtsi b/arch/arm/boot/dts/omap5.dtsi
index 187cb71..a35cd61 100644
--- a/arch/arm/boot/dts/omap5.dtsi
+++ b/arch/arm/boot/dts/omap5.dtsi
@@ -37,6 +37,9 @@
device_type = "cpu";
compatible = "arm,cortex-a15";
reg = <0x0>;
+
+ /* cooling options */
+ #cooling-cells = <2>; /* min followed by max */
};
cpu@1 {
device_type = "cpu";
--
1.8.2.1.342.gfa7285d
--
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^ permalink raw reply related [flat|nested] 31+ messages in thread
* Re: [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4)
2013-09-27 3:13 [PATCHv4 00/18] device thermal limits represented in device tree nodes (v4) Eduardo Valentin
` (13 preceding siblings ...)
[not found] ` <1380251605-3804-1-git-send-email-eduardo.valentin-l0cyMroinI0@public.gmane.org>
@ 2013-09-27 3:15 ` Eduardo Valentin
14 siblings, 0 replies; 31+ messages in thread
From: Eduardo Valentin @ 2013-09-27 3:15 UTC (permalink / raw)
To: Eduardo Valentin
Cc: swarren, pawel.moll, mark.rutland, ian.campbell, rob.herring,
linux, rui.zhang, wni, grant.likely, durgadoss.r, linux-pm,
devicetree, lm-sensors, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 4305 bytes --]
On 26-09-2013 23:13, Eduardo Valentin wrote:
> Hello all,
>
> Here is the continuation of work of representing hardware thermal properties
> in device tree infrastructure. The present patch series is the fourth version
> of this work. Previous versions were sent as RFCs and can be found here:
> V3:
Too fast, hit send too early. For those interested, here is the link to V3:
https://lkml.org/lkml/2013/9/15/122
> RFCv2: http://lkml.org/lkml/2013/8/23/594
> RFCv1: http://lkml.org/lkml/2013/7/22/319
>
> Major difference from V3 is on the parser itself. I have updated the binding
> documentation and improved the code accordingly to previous comments mainly
> from Mark R. and Joe P.
>
> The changes on hwmon drivers have been accepted by Guenter, and in this
> series I am including his Acked-by, as I didn't change anything on that side.
>
> I also found a bug while using all involved code built as modules, thus
> I have reworked a bit the cooling device registration part. This is why
> there are two new patches in this series (patches 02 and 04).
>
> Tests were done, just like in V3, on TI OMAP4430, OMAP4460, OMAP5430 and DRA7,
> although this series is not including the DRA7 part (I will be sending separately).
>
> Thanks all who have been contributing reviewing this code.
>
> All best,
>
> Eduardo Valentin (18):
> thermal: allow registering without .get_temp
> thermal: core: allow binding via .bind when tzp is present
> thermal: introduce device tree parser
> thermal: core: introduce thermal_of_cooling_device_register
> thermal: cpu_cooling: introduce of_cpufreq_cooling_register
> cpufreq: cpufreq-cpu0: add dt node parsing for cooling device
> properties
> hwmon: lm75: expose to thermal fw via DT nodes
> hwmon: tmp102: expose to thermal fw via DT nodes
> thermal: ti-soc-thermal: use thermal DT infrastructure
> arm: dts: add omap4 CPU thermal data
> arm: dts: add omap4430 thermal data
> arm: dts: add omap4460 thermal data
> arm: dts: add cooling properties on omap4430 cpu node
> arm: dts: add cooling properties on omap4460 cpu node
> arm: dts: add omap5 GPU thermal data
> arm: dts: add omap5 CORE thermal data
> arm: dts: add omap5 thermal data
> arm: dts: add cooling properties on omap5 cpu node
>
> .../devicetree/bindings/cpufreq/cpufreq-cpu0.txt | 7 +
> .../devicetree/bindings/thermal/thermal.txt | 537 +++++++++++++
> arch/arm/boot/dts/omap4-cpu-thermal.dtsi | 41 +
> arch/arm/boot/dts/omap443x.dtsi | 15 +-
> arch/arm/boot/dts/omap4460.dtsi | 15 +-
> arch/arm/boot/dts/omap5-core-thermal.dtsi | 28 +
> arch/arm/boot/dts/omap5-gpu-thermal.dtsi | 28 +
> arch/arm/boot/dts/omap5.dtsi | 15 +-
> drivers/cpufreq/Kconfig | 2 +-
> drivers/cpufreq/cpufreq-cpu0.c | 16 +
> drivers/hwmon/lm75.c | 35 +-
> drivers/hwmon/tmp102.c | 19 +
> drivers/thermal/Kconfig | 14 +
> drivers/thermal/Makefile | 1 +
> drivers/thermal/cpu_cooling.c | 56 +-
> drivers/thermal/of-thermal.c | 845 +++++++++++++++++++++
> drivers/thermal/thermal_core.c | 79 +-
> drivers/thermal/thermal_core.h | 9 +
> drivers/thermal/ti-soc-thermal/ti-thermal-common.c | 77 +-
> include/dt-bindings/thermal/thermal.h | 27 +
> include/linux/cpu_cooling.h | 25 +
> include/linux/thermal.h | 32 +-
> 22 files changed, 1880 insertions(+), 43 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/thermal/thermal.txt
> create mode 100644 arch/arm/boot/dts/omap4-cpu-thermal.dtsi
> create mode 100644 arch/arm/boot/dts/omap5-core-thermal.dtsi
> create mode 100644 arch/arm/boot/dts/omap5-gpu-thermal.dtsi
> create mode 100644 drivers/thermal/of-thermal.c
> create mode 100644 include/dt-bindings/thermal/thermal.h
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 295 bytes --]
^ permalink raw reply [flat|nested] 31+ messages in thread