soundwire: intel: prevent pm_runtime resume prior to system suspend

[ Upstream commit 6d9f2dadba698114fed97b224578c5338a36b0d9 ]

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>
Link: https://lore.kernel.org/r/20220420023241.14335-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index f72d36654ac2a9c6a9aa9681a2b5d3135d8869dd..38e7f1a2bb97d7c3acd2725ddc99621f2721412f 100644 (file)
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -1298,6 +1298,9 @@ 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);