From: Lukasz Luba <lukasz.luba@xxxxxxx>
Make it possible to bind from userspace a cooling device to an existing
thermal zone. It adds more flexibility in addition to static device tree
definitions. There is also a code for changing trip point connected to
cooling device instance in the thermal zone.
In order to bind a device to a zone, first the proper thermal zone name
must be checked from file:
cat /sys/class/thermal/thermal_zoneX/type
Then that name must be set into cooling device 'bind_tz' file:
echo 'gpu-thermal' > /sys/class/thermal/cooling_deviceY/bind_tz
Next a proper trip point must be chosen for this cooling device:
echo 2 > /sys/class/thermal/thermal_zoneX/cdev_Z_trip_point
To unbind, first set -1 to connected trip point:
echo -1 > /sys/class/thermal/thermal_zoneX/cdev_Z_trip_point
Then unbind the thermal zone from the cooling device:
echo 'gpu-thermal' > /sys/class/thermal/cooling_deviceY/unbind_tz
Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>
---
drivers/thermal/thermal_sysfs.c | 57 +++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index 80c8bae6dd1c..473449b41d55 100644
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -722,15 +722,72 @@ cur_state_store(struct device *dev, struct device_attribute *attr,
return result ? result : count;
}
+static ssize_t
+bind_tz_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct thermal_zone_device *tz;
+ char *orig, *name;
+ int res = 0;
+
+ orig = kstrndup(buf, count, GFP_KERNEL);
+ if (!orig)
+ return -ENOMEM;
+
+ name = strstrip(orig);
+
+ tz = thermal_zone_get_zone_by_name(name);
+ if (IS_ERR_OR_NULL(tz))
+ return -EINVAL;
+
+ res = thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
+ THERMAL_NO_LIMIT,
+ THERMAL_NO_LIMIT,
+ THERMAL_WEIGHT_DEFAULT);
+
+ kfree(orig);
+ return res ? res : count;
+}
+
+static ssize_t
+unbind_tz_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct thermal_cooling_device *cdev = to_cooling_device(dev);
+ struct thermal_zone_device *tz;
+ char *name, *orig;
+ int res = 0;
+
+ orig = kstrndup(buf, count, GFP_KERNEL);
+ if (!orig)
+ return -ENOMEM;
+
+ name = strstrip(orig);
+
+ tz = thermal_zone_get_zone_by_name(name);
+ if (IS_ERR_OR_NULL(tz))
+ return -EINVAL;
+
+ res = thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev);
+
+ kfree(orig);
+ return res ? res : count;
+}
+
static struct device_attribute
dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
static DEVICE_ATTR_RO(max_state);
static DEVICE_ATTR_RW(cur_state);
+static DEVICE_ATTR_WO(bind_tz);
+static DEVICE_ATTR_WO(unbind_tz);
static struct attribute *cooling_device_attrs[] = {
&dev_attr_cdev_type.attr,
&dev_attr_max_state.attr,
&dev_attr_cur_state.attr,
+ &dev_attr_bind_tz.attr,
+ &dev_attr_unbind_tz.attr,
NULL,
};
--
2.17.1
