[PATCH 2/2] drm/amd/display: Add drm_audio_component support to amdgpu_dm

[Takashi Iwai]

On Wed, 10 Jul 2019 16:36:19 +0200,
Takashi Iwai wrote:
> 
> On Wed, 10 Jul 2019 16:31:40 +0200,
> Kazlauskas, Nicholas wrote:
> > 
> > On 7/10/19 9:48 AM, Takashi Iwai wrote:
> > > On Tue, 09 Jul 2019 18:30:19 +0200,
> > > Nicholas Kazlauskas wrote:
> > >>
> > >> [Why]
> > >> The drm_audio_component can be used to give pin ELD notifications
> > >> directly to the sound driver. This fixes audio endpoints disappearing
> > >> due to missing unsolicited notifications.
> > >>
> > >> [How]
> > >> Send the notification via the audio component whenever we enable or
> > >> disable audio state on a stream. This matches what i915 does with
> > >> their drm_audio_component and what Takashi Iwai's proposed hack for
> > >> radeon/amdpgu did.
> > >>
> > >> This is a bit delayed in when the notification actually occurs, however.
> > >> We wait until after all the programming is complete rather than sending
> > >> the notification mid sequence.
> > >>
> > >> Particular care is needed for the get ELD callback since it can happen
> > >> outside the locking and fencing DRM does for atomic commits.
> > >>
> > >> Cc: Takashi Iwai <tiwai at suse.de>
> > >> Cc: Leo Li <sunpeng.li at amd.com>
> > >> Cc: Harry Wentland <harry.wentland at amd.com>
> > >> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
> > > 
> > > Thanks for the patch, this has been a long-standing TODO for me, too!
> > > 
> > > Do you have the patch for HD-audio part as well?  Or you tested with
> > > my old patch?  Then I'll resurrect my patch set as well.
> > 
> > I've tested this series with and without that patch. The notifications 
> > work and the driver will query back with get_eld as expected.
> 
> OK, then I'm going to prepare a branch including that patch.

FWIW, my latest patches are found in topic/hda-acomp branch on sound
git tree:
  git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git topic/hda-acomp

There have been a slight refactoring in HD-audio side, and now it
supports both AMD and Nvidia audio component support.  The branch
contains the patches for radeon and nouveau support.

Note that the branch isn't permanent one, it'll be rebased later.
Once after I submit and get the review for the HD-audio patches, I'll
create an immutable branch based on 5.3-rc1 containing those HD-audio
patches (but not DRM ones), so that you can pull into your drm tree
for the completeness.


thanks,

Takashi