From db91651311c8b89978b17d27634582c28c33363e Mon Sep 17 00:00:00 2001 From: Javi Merino Date: Wed, 18 Feb 2015 16:04:24 +0000 Subject: [PATCH] thermal: export weight to sysfs 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 Cc: Eduardo Valentin Signed-off-by: Javi Merino Signed-off-by: Eduardo Valentin --- 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(-) diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index 7ec632ed9769..3625453ceef6 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -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 diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c index a6cb9b78b629..605d6919c1b6 100644 --- a/drivers/thermal/thermal_core.c +++ b/drivers/thermal/thermal_core.c @@ -922,6 +922,34 @@ static const struct attribute_group *cooling_device_attr_groups[] = { NULL, }; +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 */ /** @@ -1016,6 +1044,16 @@ 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) @@ -1033,6 +1071,8 @@ 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); diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 7a465e9d456c..faebe881f062 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -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 */