Thermal: do thermal zone update after a cooling device registered
When a new cooling device is registered, we need to update the
thermal zone to set the new registered cooling device to a proper
state.
This fixes a problem that the system is cool, while the fan devices
are left running on full speed after boot, if fan device is registered
after thermal zone device.
Here is the history of why current patch looks like this:
https://patchwork.kernel.org/patch/7273041/
CC: <stable@vger.kernel.org> #3.18+
Reference:https://bugzilla.kernel.org/show_bug.cgi?id=92431
Tested-by: Manuel Krause <manuelkrause@netscape.net>
Tested-by: szegad <szegadlo@poczta.onet.pl>
Tested-by: prash <prash.n.rao@gmail.com>
Tested-by: amish <ammdispose-arch@yahoo.com>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 9aae767..ba08b55 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1341,6 +1341,7 @@
if (!result) {
list_add_tail(&dev->tz_node, &tz->thermal_instances);
list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
+ atomic_set(&tz->need_update, 1);
}
mutex_unlock(&cdev->lock);
mutex_unlock(&tz->lock);
@@ -1450,6 +1451,7 @@
const struct thermal_cooling_device_ops *ops)
{
struct thermal_cooling_device *cdev;
+ struct thermal_zone_device *pos = NULL;
int result;
if (type && strlen(type) >= THERMAL_NAME_LENGTH)
@@ -1494,6 +1496,12 @@
/* Update binding information for 'this' new cdev */
bind_cdev(cdev);
+ mutex_lock(&thermal_list_lock);
+ list_for_each_entry(pos, &thermal_tz_list, node)
+ if (atomic_cmpxchg(&pos->need_update, 1, 0))
+ thermal_zone_device_update(pos);
+ mutex_unlock(&thermal_list_lock);
+
return cdev;
}
@@ -1826,6 +1834,8 @@
tz->trips = trips;
tz->passive_delay = passive_delay;
tz->polling_delay = polling_delay;
+ /* A new thermal zone needs to be updated anyway. */
+ atomic_set(&tz->need_update, 1);
dev_set_name(&tz->device, "thermal_zone%d", tz->id);
result = device_register(&tz->device);
@@ -1921,7 +1931,9 @@
INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
thermal_zone_device_reset(tz);
- thermal_zone_device_update(tz);
+ /* Update the new thermal zone and mark it as already updated. */
+ if (atomic_cmpxchg(&tz->need_update, 1, 0))
+ thermal_zone_device_update(tz);
return tz;