@@ -194,6 +194,8 @@ thermal_zone_bind_cooling_device/thermal_zone_unbind_cooling_device.
/sys/class/thermal/thermal_zone[0-*]:
|---cdev[0-*]: [0-*]th cooling device in current thermal zone
|---cdev[0-*]_trip_point: Trip point that cdev[0-*] is associated with
+ |---cdev[0-*]_weight: Influence of the cooling device in
+ this thermal zone
Besides the thermal zone device sysfs I/F and cooling device sysfs I/F,
the generic thermal driver also creates a hwmon sysfs I/F for each _type_
@@ -267,6 +269,14 @@ cdev[0-*]_trip_point
point.
RO, Optional
+cdev[0-*]_weight
+ The influence of cdev[0-*] in this thermal zone. This value
+ is relative to the rest of cooling devices in the thermal
+ zone. For example, if a cooling device has a weight double
+ than that of other, it's twice as effective in cooling the
+ thermal zone.
+ RW, Optional
+
passive
Attribute is only present for zones in which the passive cooling
policy is not supported by native thermal driver. Default is zero
@@ -320,7 +330,8 @@ passive, active. If an ACPI thermal zone supports critical, passive,
active[0] and active[1] at the same time, it may register itself as a
thermal_zone_device (thermal_zone1) with 4 trip points in all.
It has one processor and one fan, which are both registered as
-thermal_cooling_device.
+thermal_cooling_device. Both are considered to have the same
+effectiveness in cooling the thermal zone.
If the processor is listed in _PSL method, and the fan is listed in _AL0
method, the sys I/F structure will be built like this:
@@ -342,8 +353,10 @@ method, the sys I/F structure will be built like this:
|---trip_point_3_type: active1
|---cdev0: --->/sys/class/thermal/cooling_device0
|---cdev0_trip_point: 1 /* cdev0 can be used for passive */
+ |---cdev0_weight: 1024
|---cdev1: --->/sys/class/thermal/cooling_device3
|---cdev1_trip_point: 2 /* cdev1 can be used for active[0]*/
+ |---cdev1_weight: 1024
|cooling_device0:
|---type: Processor
@@ -904,6 +904,34 @@ thermal_cooling_device_trip_point_show(struct device *dev,
return sprintf(buf, "%d\n", instance->trip);
}
+static ssize_t
+thermal_cooling_device_weight_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct thermal_instance *instance;
+
+ instance = container_of(attr, struct thermal_instance, weight_attr);
+
+ return sprintf(buf, "%d\n", instance->weight);
+}
+
+static ssize_t
+thermal_cooling_device_weight_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct thermal_instance *instance;
+ int ret, weight;
+
+ ret = kstrtoint(buf, 0, &weight);
+ if (ret)
+ return ret;
+
+ instance = container_of(attr, struct thermal_instance, weight_attr);
+ instance->weight = weight;
+
+ return count;
+}
/* Device management */
/**
@@ -998,6 +1026,16 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
if (result)
goto remove_symbol_link;
+ sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
+ sysfs_attr_init(&dev->weight_attr.attr);
+ dev->weight_attr.attr.name = dev->weight_attr_name;
+ dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
+ dev->weight_attr.show = thermal_cooling_device_weight_show;
+ dev->weight_attr.store = thermal_cooling_device_weight_store;
+ result = device_create_file(&tz->device, &dev->weight_attr);
+ if (result)
+ goto remove_trip_file;
+
mutex_lock(&tz->lock);
mutex_lock(&cdev->lock);
list_for_each_entry(pos, &tz->thermal_instances, tz_node)
@@ -1015,6 +1053,8 @@ int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
if (!result)
return 0;
+ device_remove_file(&tz->device, &dev->weight_attr);
+remove_trip_file:
device_remove_file(&tz->device, &dev->attr);
remove_symbol_link:
sysfs_remove_link(&tz->device.kobj, dev->name);
@@ -46,6 +46,8 @@ struct thermal_instance {
unsigned long target; /* expected cooling state */
char attr_name[THERMAL_NAME_LENGTH];
struct device_attribute attr;
+ char weight_attr_name[THERMAL_NAME_LENGTH];
+ struct device_attribute weight_attr;
struct list_head tz_node; /* node in tz->thermal_instances */
struct list_head cdev_node; /* node in cdev->thermal_instances */
unsigned int weight; /* The weight of the cooling device */
It's useful to have access to the weights for the cooling devices for thermal zones and change them if needed. Export them to sysfs. Cc: Zhang Rui <rui.zhang@intel.com> Cc: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Javi Merino <javi.merino@arm.com> --- Documentation/thermal/sysfs-api.txt | 15 +++++++++++++- drivers/thermal/thermal_core.c | 40 +++++++++++++++++++++++++++++++++++++ drivers/thermal/thermal_core.h | 2 ++ 3 files changed, 56 insertions(+), 1 deletion(-)