[SRU][OEM-5.6][PATCH 0/1] The DP/HDMI audio via USB-C to DP dongle or Dell Zeus adapter can't work after suspend

[Hui Wang]

BugLink: https://bugs.launchpad.net/bugs/1893290

Since this patch is CCed to stable kernel, I just sent this patch
to oem-5.6 kernel, our oem project is waiting for this patch to
be landed to oem-5.6 kernel first.

[Impact]
On the Dell TGL laptop, if connecting a monitor via type-c to DP/HDMI
adapter, we will have an audio issue, that is playing the music and
suspend the system, after resuming back, the audio can't output from
DP/HDMI monitor anymore.

[Fix]
Cherry-pick a fix from upstream, this patch is verifying the needed
converter and pin to be in the D0 state.

[Test Case]
Connect a monitor with USB-C to DP/HDMI adapter, open the youtu.com
and playing sth, suspend the system and resume, check if the sound
could play the music, repeat 20 times, all work very well.

[Regression Risk]
If this patch could introduce regression, it should be the power
consumption regression on Intel HDMI audio, since it makes the
converter and pin to be D0 state earlier than before. But this
impact is very small. one converter and one pin consume very little
power.

Kai Vehmanen (1):
  ALSA: hda/hdmi: always check pin power status in i915 pin fixup

 sound/pci/hda/patch_hdmi.c | 1 +
 1 file changed, 1 insertion(+)

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2.17.1