From cb1e6d59e89ce272a67e6dc22e9ec72df622fb1b Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 17 Aug 2020 23:29:14 +0800 Subject: 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 Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20200817152923.3259-4-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul --- drivers/soundwire/intel.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/soundwire/intel.c') diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 0e21bae3cd19..00c5de1250ec 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -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; } -- cgit v1.2.3