[PATCH 0/1][SRU][[B][OEM-B] No audio output from Dell WD19 HDMI/DP after resumed from S3 or s2idle

[AceLan Kao]

BugLink: https://bugs.launchpad.net/bugs/1869642

[Impact]
Plug-in HDMI/DP cable onto docking station after system resumed from
S3/s2idle, there is no audio output from HDMI/DP even if you select the
HDMI/DP audio output manually from sound settings.
It shows this in dmesg when try testing speakers from sound settings
[ 2052.030247] snd_hda_codec_hdmi hdaudioC0D2: Unable to sync register 0x2f0d00. -5

[Fix]
This issue has been fixed in 4.16-rc1 by below commit
4918e1f87c5f PM / runtime: Rework pm_runtime_force_suspend/resume()

[Test]
Verified on Dell Latitude 3310 + Dell WD19 docking station

[Regression Potential]
Low, it fixes the device usage counter, and should also fix some other
runpm issues.

Rafael J. Wysocki (1):
  PM / runtime: Rework pm_runtime_force_suspend/resume()

 drivers/base/power/runtime.c | 74 +++++++++++++++++-------------------
 1 file changed, 34 insertions(+), 40 deletions(-)

-- 
2.17.1