PM / runtime: Use pm_runtime_put_sync() in __device_release_driver()

Commit fa180eb448fa (PM / Runtime: Idle devices asynchronously after
probe|release) modified __device_release_driver() to call
pm_runtime_put(dev) instead of pm_runtime_put_sync(dev) before
detaching the driver from the device.  However, that was a mistake,
because pm_runtime_put(dev) causes rpm_idle() to be queued up and
the driver may be gone already when that function is executed.
That breaks the assumptions the drivers have the right to make
about the core's behavior on the basis of the existing documentation
and actually causes problems to happen, so revert that part of
commit fa180eb448fa and restore the previous behavior of
__device_release_driver().

Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Fixes: fa180eb448fa (PM / Runtime: Idle devices asynchronously after probe|release)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+

diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 35fa368989162fcadc0d6ee7b025c9f323fc9128..06051767393f7638d4ea02a14bfc5a8a689a0305 100644 (file)
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -499,7 +499,7 @@ static void __device_release_driver(struct device *dev)
                                                     BUS_NOTIFY_UNBIND_DRIVER,
                                                     dev);
 
-               pm_runtime_put(dev);
+               pm_runtime_put_sync(dev);
 
                if (dev->bus && dev->bus->remove)
                        dev->bus->remove(dev);