[alsa-devel] [PATCH 2/2] [RFC] ALSA: hda: hdmi - preserve non-MST PCM routing for Intel platforms

[Takashi Iwai]

On Fri, 29 Nov 2019 15:37:56 +0100,
Kai Vehmanen wrote:
> 
> Commit 5398e94fb753 ("ALSA: hda - Add DP-MST support for NVIDIA codecs")
> introduced a slight change of behaviour how non-MST monitors are
> assigned to PCMs on Intel platforms.
> 
> In the drm_audio_component.h interface, the third parameter
> to pin_eld_notify() is pipe number. On Intel platforms, this value
> is -1 for MST. On other platforms, a non-zero pipe id is used to
> signal MST use.
> 
> This difference leads to some subtle differences in hdmi_find_pcm_slot()
> with regards to how non-MST monitors are assigned to PCMs.
> This patch restores the original behaviour on Intel platforms while
> keeping the new allocation policy on other platforms.
> 
> Signed-off-by: Kai Vehmanen <kai.vehmanen at linux.intel.com>

I believe this is the right fix.  I thought of a similar possibility,
but didn't take it seriously whether it really matters.

So applied it now for the next 5.5-rc1 pull request.


thanks,

Takashi