Commit cb1e6d59 authored Aug 17, 2020 by Pierre-Louis Bossart Committed by Vinod Koul Aug 18, 2020

soundwire: intel: fix race condition on system resume

Previous patches took care of the case where the master device is
pm_runtime 'suspended' when a system suspend occurs.

In the case where the master device was not suspended, e.g. if suspend
occurred while streaming audio, Intel validation noticed a race
condition: the pm_runtime suspend may conflict with the enumeration
started by the system resume.

This can be simply fixed by updating the status before exiting system
resume.

GitHub issue: https://github.com/thesofproject/linux/issues/1482


Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200817152923.3259-4-yung-chuan.liao@linux.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>

parent b61b8b37

drivers/soundwire/intel.c

+12 −0

Original line number	Diff line number	Diff line
		@@ -1528,6 +1528,18 @@ static int intel_resume(struct device *dev)
		return ret;
		}

		/*
		* after system resume, the pm_runtime suspend() may kick in
		* during the enumeration, before any children device force the
		* master device to remain active. Using pm_runtime_get()
		* routines is not really possible, since it'd prevent the
		* master from suspending.
		* A reasonable compromise is to update the pm_runtime
		* counters and delay the pm_runtime suspend by several
		* seconds, by when all enumeration should be complete.
		*/
		pm_runtime_mark_last_busy(dev);

		return ret;
		}

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