[PATCH v3 1/6] thermal: Add a new trip type to use cooling device instance number

Amit Daniel Kachhap
2012-05-08T16:18:42Z

This patch adds a new trip type THERMAL_TRIP_STATE_INSTANCE. This
trip behaves same as THERMAL_TRIP_ACTIVE but also passes the cooling
device instance number. This helps the cooling device registered as
different instances to perform appropriate cooling action decision in
the set_cur_state call back function.

Also since the trip temperature's are in ascending order so some logic
is put in place to skip the un-necessary checks during thermal zone
update and return error when failing the ascending order trip point check
during thermal zone registration.

Signed-off-by: Amit Daniel Kachhap <amit.kachhap@linaro.org>
---
Documentation/thermal/sysfs-api.txt | 4 +-
drivers/thermal/thermal_sys.c | 62 +++++++++++++++++++++++++++++++++--
include/linux/thermal.h | 1 +
3 files changed, 62 insertions(+), 5 deletions(-)

diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index 1733ab9..9a7c69c 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -184,8 +184,8 @@ trip_point_[0-*]_temp

trip_point_[0-*]_type
Strings which indicate the type of the trip point.
- E.g. it can be one of critical, hot, passive, active[0-*] for ACPI
- thermal zone.
+ E.g. it can be one of critical, hot, passive, active[0-1],
+ state-instance[0-*] for ACPI thermal zone.
RO, Optional

cdev[0-*]
diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index 022bacb..4ae93fb 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -190,6 +190,8 @@ trip_point_type_show(struct device *dev, struct device_attribute *attr,
return sprintf(buf, "passive\n");
case THERMAL_TRIP_ACTIVE:
return sprintf(buf, "active\n");
+ case THERMAL_TRIP_STATE_INSTANCE:
+ return sprintf(buf, "state-instance\n");
default:
return sprintf(buf, "unknown\n");
}
@@ -1013,10 +1015,10 @@ EXPORT_SYMBOL(thermal_cooling_device_unregister);

void thermal_zone_device_update(struct thermal_zone_device *tz)
{
- int count, ret = 0;
- long temp, trip_temp;
+ int count, ret = 0, inst_id;
+ long temp, trip_temp, max_state, last_trip_change = 0;
enum thermal_trip_type trip_type;
- struct thermal_cooling_device_instance *instance;
+ struct thermal_cooling_device_instance *instance, *state_instance;
struct thermal_cooling_device *cdev;

mutex_lock(&tz->lock);
@@ -1063,6 +1065,43 @@ void thermal_zone_device_update(struct thermal_zone_device *tz)
cdev->ops->set_cur_state(cdev, 0);
}
break;
+ case THERMAL_TRIP_STATE_INSTANCE:
+ list_for_each_entry(instance, &tz->cooling_devices,
+ node) {
+ if (instance->trip != count)
+ continue;
+
+ if (temp <= last_trip_change)
+ continue;
+
+ inst_id = 0;
+ /*
+ *For this instance how many instance of same
+ *cooling device occured before
+ */
+
+ list_for_each_entry(state_instance,
+ &tz->cooling_devices, node) {
+ if (instance->cdev ==
+ state_instance->cdev)
+ inst_id++;
+ if (state_instance->trip == count)
+ break;
+ }
+
+ cdev = instance->cdev;
+ cdev->ops->get_max_state(cdev, &max_state);
+
+ if ((temp >= trip_temp) &&
+ (inst_id <= max_state))
+ cdev->ops->set_cur_state(cdev, inst_id);
+ else if ((temp < trip_temp) &&
+ (--inst_id <= max_state))
+ cdev->ops->set_cur_state(cdev, inst_id);
+
+ last_trip_change = trip_temp;
+ }
+ break;
case THERMAL_TRIP_PASSIVE:
if (temp >= trip_temp || tz->passive)
thermal_zone_device_passive(tz, temp,
@@ -1117,6 +1156,7 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
int result;
int count;
int passive = 0;
+ long first_trip_temp, trip_temp;

if (strlen(type) >= THERMAL_NAME_LENGTH)
return ERR_PTR(-EINVAL);
@@ -1175,6 +1215,7 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
goto unregister;
}

+ first_trip_temp = 0;
for (count = 0; count < trips; count++) {
result = device_create_file(&tz->device,
&trip_point_attrs[count * 2]);
@@ -1187,6 +1228,21 @@ struct thermal_zone_device *thermal_zone_device_register(char *type,
tz->ops->get_trip_type(tz, count, &trip_type);
if (trip_type == THERMAL_TRIP_PASSIVE)
passive = 1;
+ /*
+ * For THERMAL_TRIP_STATE_INSTANCE trips, thermal zone should
+ * be in ascending order.
+ */
+ if (trip_type == THERMAL_TRIP_STATE_INSTANCE) {
+ tz->ops->get_trip_temp(tz, count, &trip_temp);
+ if (first_trip_temp == 0)
+ first_trip_temp = trip_temp;
+ else if (first_trip_temp < trip_temp)
+ first_trip_temp = trip_temp;
+ else if (first_trip_temp > trip_temp) {
+ pr_warn("Zone trip points should be in ascending order\n");
+ goto unregister;
+ }
+ }
}

if (!passive)
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 796f1ff..583fbda 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -42,6 +42,7 @@ enum thermal_trip_type {
THERMAL_TRIP_PASSIVE,
THERMAL_TRIP_HOT,
THERMAL_TRIP_CRITICAL,
+ THERMAL_TRIP_STATE_INSTANCE,
};

struct thermal_zone_device_ops {
--
1.7.1