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PM / runtime: Drop usage count for suppliers at device link removal

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In the case consumer device is runtime resumed, while the link to the
supplier is removed, the earlier call to pm_runtime_get_sync() made from
rpm_get_suppliers() does not get properly balanced with a corresponding
call to pm_runtime_put(). This leads to that suppliers remains to be
runtime resumed forever, while they don't need to.

Let's fix the behaviour by calling rpm_put_suppliers() when dropping a
device link. Not that, since rpm_put_suppliers() checks the
link->rpm_active flag, we can correctly avoid to call pm_runtime_put() in
cases when we shouldn't.

Reported-by: Todor Tomov <todor.tomov@linaro.org>
Fixes: 21d5c57b37 (PM / runtime: Use device links)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Ulf Hansson 2018-05-24 10:33:36 +02:00 committed by Rafael J. Wysocki
parent 1e83786198
commit a0504aecba
1 changed files with 2 additions and 0 deletions
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2
drivers/base/power/runtime.c
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@ -1586,6 +1586,8 @@ void pm_runtime_new_link(struct device *dev)
void pm_runtime_drop_link(struct device *dev)
{
rpm_put_suppliers(dev);
spin_lock_irq(&dev->power.lock);
WARN_ON(dev->power.links_count == 0);
dev->power.links_count--;