PM: Allow pm_runtime_suspend() to succeed during system suspend
commite8665002477f0278f84f898145b1f141ba26ee26
authorRafael J. Wysocki <rjw@sisk.pl>
Sat, 12 Feb 2011 00:42:41 +0000 (12 01:42 +0100)
committerRafael J. Wysocki <rjw@sisk.pl>
Mon, 14 Mar 2011 23:43:16 +0000 (15 00:43 +0100)
treef22348cc3c0cf341216d422e01d2ac033973a0a5
parent88a6f33e4d7143f94f8e787fa4065ac873507984
PM: Allow pm_runtime_suspend() to succeed during system suspend

The dpm_prepare() function increments the runtime PM reference
counters of all devices to prevent pm_runtime_suspend() from
executing subsystem-level callbacks.  However, this was supposed to
guard against a specific race condition that cannot happen, because
the power management workqueue is freezable, so pm_runtime_suspend()
can only be called synchronously during system suspend and we can
rely on subsystems and device drivers to avoid doing that
unnecessarily.

Make dpm_prepare() drop the runtime PM reference to each device
after making sure that runtime resume is not pending for it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Kevin Hilman <khilman@ti.com>
drivers/base/power/main.c