* [PATCH v4 RESEND 1/2] dt-bindings: Add DT bindings for the DT-based virtual sensor driver
2022-01-11 10:33 [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor Alexandre Bailon
@ 2022-01-11 10:33 ` Alexandre Bailon
2022-02-04 8:08 ` Daniel Lezcano
2022-01-11 10:33 ` [PATCH v4 RESEND 2/2] thermal: add a virtual sensor to aggregate temperatures Alexandre Bailon
2022-01-24 16:58 ` [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor Kevin Hilman
2 siblings, 1 reply; 9+ messages in thread
From: Alexandre Bailon @ 2022-01-11 10:33 UTC (permalink / raw)
To: rafael, rui.zhang, daniel.lezcano, amitk
Cc: linux-pm, linux-kernel, ben.tseng, khilman, mka, Alexandre Bailon
This adds the DT bindings for the DT-based virtual sensor driver.
This driver provides a way, using DT, to aggregate the temperature
of multiple thermal zones and get some useful data from it.
Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
---
.../thermal/virtual,thermal-sensor.yaml | 86 +++++++++++++++++++
include/dt-bindings/thermal/virtual-sensor.h | 15 ++++
2 files changed, 101 insertions(+)
create mode 100644 Documentation/devicetree/bindings/thermal/virtual,thermal-sensor.yaml
create mode 100644 include/dt-bindings/thermal/virtual-sensor.h
diff --git a/Documentation/devicetree/bindings/thermal/virtual,thermal-sensor.yaml b/Documentation/devicetree/bindings/thermal/virtual,thermal-sensor.yaml
new file mode 100644
index 000000000000..b404fd4b2b38
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/virtual,thermal-sensor.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright 2021 BayLibre
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/thermal/virtual,thermal-sensor.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Virtual thermal sensor binding
+
+maintainers:
+ - Alexandre Bailon <abailon@baylibre.com>
+
+description: |
+ The virtual thermal sensor device provides a way to aggregate the temperature
+ from multiple thermal zones. Basically, this could be used to get the
+ maximum, minimum or average temperature.
+
+allOf:
+ - $ref: thermal-sensor.yaml#
+
+properties:
+ compatible:
+ const: virtual,thermal-sensor
+
+ aggregation-function:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Used to select the operations to perform on the sensors to get the virtual
+ sensor temperature.
+ enum:
+ - VIRTUAL_THERMAL_SENSOR_MIN_VAL
+ - VIRTUAL_THERMAL_SENSOR_MAX_VAL
+ - VIRTUAL_THERMAL_SENSOR_AVG_VAL
+
+ thermal-sensors:
+ $ref: /schemas/types.yaml#/definitions/string-array
+ description:
+ The names of the thermal zone to aggregate.
+
+required:
+ - aggregation-function
+ - thermal-sensors
+
+additionalProperties: true
+
+examples:
+ - |
+ #include <dt-bindings/thermal/thermal.h>
+ #include <dt-bindings/thermal/virtual-sensor.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/clock/mt8192-clk.h>
+
+ lvts: lvts@1100b000 {
+ compatible = "mediatek,mt6873-lvts";
+ reg = <0x1100b000 0x1000>;
+ clocks = <&infracfg CLK_INFRA_THERM>;
+ clock-names = "lvts_clk";
+ #thermal-sensor-cells = <1>;
+ interrupts = <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>;
+ };
+
+ cpu_max_sensor: cpu_max_sensor {
+ compatible = "virtual,thermal-sensor";
+ #thermal-sensor-cells = <1>;
+ aggregation-function = <VIRTUAL_THERMAL_SENSOR_MAX_VAL>;
+ thermal-sensors = "cpu1", "cpu2";
+ };
+
+ thermal_zones: thermal-zones {
+ cpu1 {
+ polling-delay = <0>; /* milliseconds */
+ polling-delay-passive = <0>; /* milliseconds */
+ thermal-sensors = <&lvts 0>;
+ };
+ cpu2 {
+ polling-delay = <0>; /* milliseconds */
+ polling-delay-passive = <0>; /* milliseconds */
+ thermal-sensors = <&lvts 1>;
+ };
+ cpu_max {
+ polling-delay = <0>; /* milliseconds */
+ polling-delay-passive = <0>; /* milliseconds */
+ thermal-sensors = <&cpu_max_sensor 0>;
+ };
+ };
+...
diff --git a/include/dt-bindings/thermal/virtual-sensor.h b/include/dt-bindings/thermal/virtual-sensor.h
new file mode 100644
index 000000000000..6254b2aa8f5c
--- /dev/null
+++ b/include/dt-bindings/thermal/virtual-sensor.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This header provides constants for virtual thermal sensor bindings.
+ *
+ * Copyright (C) 2021 BayLibre
+ */
+
+#ifndef _DT_BINDINGS_THERMAL_VIRTUAL_SENSOR_H
+#define _DT_BINDINGS_THERMAL_VIRTUAL_SENSOR_H
+
+#define VIRTUAL_THERMAL_SENSOR_MIN_VAL 0
+#define VIRTUAL_THERMAL_SENSOR_MAX_VAL 1
+#define VIRTUAL_THERMAL_SENSOR_AVG_VAL 2
+
+#endif /* _DT_BINDINGS_THERMAL_VIRTUAL_SENSOR_H */
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v4 RESEND 2/2] thermal: add a virtual sensor to aggregate temperatures
2022-01-11 10:33 [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor Alexandre Bailon
2022-01-11 10:33 ` [PATCH v4 RESEND 1/2] dt-bindings: Add DT bindings for the DT-based virtual sensor driver Alexandre Bailon
@ 2022-01-11 10:33 ` Alexandre Bailon
2022-01-24 16:58 ` [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor Kevin Hilman
2 siblings, 0 replies; 9+ messages in thread
From: Alexandre Bailon @ 2022-01-11 10:33 UTC (permalink / raw)
To: rafael, rui.zhang, daniel.lezcano, amitk
Cc: linux-pm, linux-kernel, ben.tseng, khilman, mka, Alexandre Bailon
This adds a virtual thermal sensor driver that reads temperature from
multiple hardware sensors and returns an aggregated temperature.
Currently, this supports three aggregations:
the minimum, maximum and average temperature.
Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
---
drivers/thermal/Kconfig | 8 +
drivers/thermal/Makefile | 1 +
drivers/thermal/virtual_thermal_sensor.c | 218 +++++++++++++++++++++++
3 files changed, 227 insertions(+)
create mode 100644 drivers/thermal/virtual_thermal_sensor.c
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index d7f44deab5b1..b326fae5ad1d 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -228,6 +228,14 @@ config THERMAL_MMIO
register or shared memory, is a potential candidate to work with this
driver.
+config VIRTUAL_THERMAL
+ tristate "DT-based virtual thermal sensor driver"
+ depends on THERMAL_OF || COMPILE_TEST
+ help
+ This option enables the generic DT-based thermal sensor aggregator.
+ This driver creates a thermal sensor that reads multiple hardware
+ sensors and aggregates their output.
+
config HISI_THERMAL
tristate "Hisilicon thermal driver"
depends on ARCH_HISI || COMPILE_TEST
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 82fc3e616e54..8bf55973059c 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -60,3 +60,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o
obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o
obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o
obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o
+obj-$(CONFIG_VIRTUAL_THERMAL) += virtual_thermal_sensor.o
diff --git a/drivers/thermal/virtual_thermal_sensor.c b/drivers/thermal/virtual_thermal_sensor.c
new file mode 100644
index 000000000000..9f38af925fd1
--- /dev/null
+++ b/drivers/thermal/virtual_thermal_sensor.c
@@ -0,0 +1,218 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * virtual_thermal_sensor.c - DT-based virtual thermal sensor driver.
+ *
+ * Copyright (c) 2021 BayLibre
+ */
+
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+#include <linux/types.h>
+#include <linux/string.h>
+
+#include <dt-bindings/thermal/virtual-sensor.h>
+
+struct virtual_thermal_zone_device {
+ struct thermal_zone_device *zone;
+ struct module *owner;
+};
+
+struct virtual_thermal_sensor {
+ int count;
+ struct virtual_thermal_zone_device *zones;
+ struct thermal_zone_device *tzd;
+ int (*aggr_temp)(int temp1, int temp2);
+
+ struct list_head node;
+};
+
+static int max_temp(int temp1, int temp2)
+{
+ return max(temp1, temp2);
+}
+
+static int min_temp(int temp1, int temp2)
+{
+ return min(temp1, temp2);
+}
+
+static int avg_temp(int temp1, int temp2)
+{
+ return (temp1 + temp2) / 2;
+}
+
+static int virtual_thermal_sensor_get_temp(void *data, int *temperature)
+{
+ struct virtual_thermal_sensor *sensor = data;
+ int max_temp = INT_MIN;
+ int temp;
+ int i;
+
+ for (i = 0; i < sensor->count; i++) {
+ struct thermal_zone_device *zone;
+
+ zone = sensor->zones[i].zone;
+ zone->ops->get_temp(zone, &temp);
+ max_temp = sensor->aggr_temp(max_temp, temp);
+ }
+
+ *temperature = max_temp;
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops virtual_thermal_sensor_ops = {
+ .get_temp = virtual_thermal_sensor_get_temp,
+};
+
+static int virtual_thermal_sensor_get_module(struct virtual_thermal_zone_device *zone,
+ const char *name)
+{
+ struct platform_device *sensor_pdev;
+ struct device_node *node;
+
+ node = of_find_node_by_name(NULL, name);
+ if (!node)
+ return -ENODEV;
+
+ node = of_parse_phandle(node, "thermal-sensors", 0);
+ if (!node)
+ return -ENODEV;
+
+ sensor_pdev = of_find_device_by_node(node);
+ if (!sensor_pdev)
+ return -ENODEV;
+
+ if (!sensor_pdev->dev.driver)
+ return -EPROBE_DEFER;
+
+ if (!try_module_get(sensor_pdev->dev.driver->owner))
+ return -ENODEV;
+
+ zone->owner = sensor_pdev->dev.driver->owner;
+
+ return 0;
+}
+
+static void virtual_thermal_sensor_put_modules(struct virtual_thermal_sensor *sensor)
+{
+ int i;
+
+ for (i = 0; i < sensor->count; i++) {
+ if (sensor->zones[i].zone)
+ module_put(sensor->zones[i].owner);
+ }
+}
+
+static int virtual_thermal_sensor_probe(struct platform_device *pdev)
+{
+ struct virtual_thermal_sensor *sensor;
+ struct device *dev = &pdev->dev;
+ struct property *prop;
+ const char *name;
+ u32 type;
+ int ret;
+ int i = 0;
+
+ sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL);
+ if (!sensor)
+ return -ENOMEM;
+ sensor->count = of_property_count_strings(dev->of_node, "thermal-sensors");
+ if (sensor->count <= 0)
+ return -EINVAL;
+
+ sensor->zones = devm_kmalloc_array(dev, sensor->count,
+ sizeof(*sensor->zones),
+ GFP_KERNEL);
+ if (!sensor->zones)
+ return -ENOMEM;
+
+ of_property_for_each_string(dev->of_node, "thermal-sensors", prop, name) {
+ struct virtual_thermal_zone_device *virtual_zone;
+ struct thermal_zone_device *zone;
+
+ virtual_zone = &sensor->zones[i++];
+
+ zone = thermal_zone_get_zone_by_name(name);
+ if (IS_ERR(zone))
+ return PTR_ERR(zone);
+
+ ret = virtual_thermal_sensor_get_module(virtual_zone, name);
+ if (ret)
+ goto err;
+
+ virtual_zone->zone = zone;
+ }
+
+ ret = of_property_read_u32(dev->of_node, "aggregation-function", &type);
+ if (ret)
+ return ret;
+
+ switch (type) {
+ case VIRTUAL_THERMAL_SENSOR_MAX_VAL:
+ sensor->aggr_temp = max_temp;
+ break;
+ case VIRTUAL_THERMAL_SENSOR_MIN_VAL:
+ sensor->aggr_temp = min_temp;
+ break;
+ case VIRTUAL_THERMAL_SENSOR_AVG_VAL:
+ sensor->aggr_temp = avg_temp;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ sensor->tzd = devm_thermal_zone_of_sensor_register(dev, 0, sensor,
+ &virtual_thermal_sensor_ops);
+ if (IS_ERR(sensor->tzd))
+ return PTR_ERR(sensor->tzd);
+
+ platform_set_drvdata(pdev, sensor);
+
+ return 0;
+
+err:
+ virtual_thermal_sensor_put_modules(sensor);
+
+ return ret;
+}
+
+static int virtual_thermal_sensor_remove(struct platform_device *pdev)
+{
+ struct virtual_thermal_sensor *sensor;
+
+ sensor = platform_get_drvdata(pdev);
+ list_del(&sensor->node);
+
+ virtual_thermal_sensor_put_modules(sensor);
+
+ return 0;
+}
+
+static const struct of_device_id virtual_thermal_sensor_of_match[] = {
+ {
+ .compatible = "virtual,thermal-sensor",
+ },
+ {
+ },
+};
+MODULE_DEVICE_TABLE(of, virtual_thermal_sensor_of_match);
+
+static struct platform_driver virtual_thermal_sensor = {
+ .probe = virtual_thermal_sensor_probe,
+ .remove = virtual_thermal_sensor_remove,
+ .driver = {
+ .name = "virtual-thermal-sensor",
+ .of_match_table = virtual_thermal_sensor_of_match,
+ },
+};
+
+module_platform_driver(virtual_thermal_sensor);
+MODULE_AUTHOR("Alexandre Bailon <abailon@baylibre.com>");
+MODULE_DESCRIPTION("Virtual thermal sensor");
+MODULE_LICENSE("GPL v2");
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor
2022-01-11 10:33 [PATCH v4 RESEND 0/2] Add a generic virtual thermal sensor Alexandre Bailon
2022-01-11 10:33 ` [PATCH v4 RESEND 1/2] dt-bindings: Add DT bindings for the DT-based virtual sensor driver Alexandre Bailon
2022-01-11 10:33 ` [PATCH v4 RESEND 2/2] thermal: add a virtual sensor to aggregate temperatures Alexandre Bailon
@ 2022-01-24 16:58 ` Kevin Hilman
2022-01-24 18:52 ` Rafael J. Wysocki
2 siblings, 1 reply; 9+ messages in thread
From: Kevin Hilman @ 2022-01-24 16:58 UTC (permalink / raw)
To: daniel.lezcano, amitk
Cc: linux-pm, linux-kernel, ben.tseng, mka, Alexandre Bailon,
Alexandre Bailon, rafael, rui.zhang
Daniel, Amit,
Alexandre Bailon <abailon@baylibre.com> writes:
> This series add a virtual thermal sensor.
> It could be used to get a temperature using some thermal sensors.
> Currently, the supported operations are max, min and avg.
> The virtual sensor could be easily extended to support others operations.
>
> Changes in v2:
> - Fix some warnings / errors reported by kernel test robot
> - rename some struct and functions with a more accurate name
> - update the dt bindings: rename type attribute to aggregation-function
> - factorize a little bit the aggregation functions
> Changes in v3:
> - Aggregate thermal zone instead of thermal sensors
> - Use try_get_module / put_module to prevent thermal providers to be removed
> - Update the bindings, to be more accurate
> Changes in v4:
> - Fix two warnings reported by kernel test robot
Any more feedback on this series?
Thanks,
Kevin
^ permalink raw reply [flat|nested] 9+ messages in thread