From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
commit e38f9ff63e6d ("ACPI: scan: Do not add device IDs from _CID if _HID is not valid") exposes a race condition on a TGL RVP device leading to a timeout.
The detailed analysis shows the RT711 codec driver scheduling a jack detection workqueue while attaching during a spurious pm_runtime resume, and the work function happens to be scheduled after the manager device is suspended.
The direct link between this ACPI patch and a spurious pm_runtime resume is not obvious; the most likely explanation is that a change in the ACPI device linked list management modifies the order in which the pm_runtime device status is checked and exposes a race condition that was probably present for a very long time, but was not identified.
We already have a check in the .prepare stage, where we will resume to full power from specific clock-stop modes. In all other cases, we don't need to resume to full power by default. Adding the SMART_SUSPEND flag prevents the spurious resume from happening.
BugLink: https://github.com/thesofproject/linux/issues/3459 Fixes: 029bfd1cd53cd ("soundwire: intel: conditionally exit clock stop mode on system suspend") Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 63101f1ba271..32e5fdb823c4 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1293,6 +1293,9 @@ static int intel_link_probe(struct auxiliary_device *auxdev, /* use generic bandwidth allocation algorithm */ sdw->cdns.bus.compute_params = sdw_compute_params;
+ /* avoid resuming from pm_runtime suspend if it's not required */ + dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND); + ret = sdw_bus_master_add(bus, dev, dev->fwnode); if (ret) { dev_err(dev, "sdw_bus_master_add fail: %d\n", ret);