| Message ID | 20230803065220.3823269-1-yung-chuan.liao@linux.intel.com |
|---|---|
| Headers | show |
| Series | soundwire: improve pm_runtime handling | expand |
On Thu, Aug 03, 2023 at 02:52:19PM +0800, Bard Liao wrote: > From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > > As soon as the bus starts, physical peripheral devices may report as > ATTACHED and set their status with pm_runtime_set_active() in their > update_status()/io_init(). > > This is problematic with the existing code, since the parent > pm_runtime status is changed to "active" after starting the bus. This > creates a time window where the pm_runtime framework can report an > issue, e.g. > > "rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device > sdw:0:025d:0711:00 but parent (sdw-master-0) is not active" > > This patch enables runtime_pm earlier to make sure the auxiliary > device is pm_runtime active after powering-up, but before starting the > bus. > > This problem was exposed by recent changes in the timing of the bus > reset, but was present in this driver since we introduced pm_runtime > support. > > Closes: https://github.com/thesofproject/linux/issues/4328 > 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> > --- Doesn't seem to cause any problems on my SoundWire devices, so very loosely: Tested-by: Charles Keepax <ckeepax@opensource.cirrus.com> Thanks, Charles
This patchset improves the pm_runtime behavior in rare corner cases identified by the Intel CI in the last 6 months. a) in stress-tests, it's not uncommon to see the following type of warnings when the codec reports as ATTACHED "rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active" This warning was not correlated with any functional issue, but it exposed a design issue on when to enable pm_runtime. The recommended practice in the pm_runtime documentation is to keep the devices in 'suspended' mode and mark them as 'active' when they are really functional. Pierre-Louis Bossart (2): soundwire: intel_auxdevice: enable pm_runtime earlier on startup soundWire: intel_auxdevice: resume 'sdw-master' on startup and system resume drivers/soundwire/intel_auxdevice.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-)