[PATCH 1/7] drm/vc4: hdmi: Check that the monitor supports HDMI audio

[Stefan Wahren]

> Eric Anholt <eric at anholt.net> hat am 4. März 2019 um 19:28 geschrieben:
> 
> 
> Stefan Wahren <stefan.wahren at i2se.com> writes:
> 
> > Hi Maxime,
> >
> > Am 04.03.2019 um 15:52 schrieb Maxime Ripard:
> >> The current code assumes as soon as the device is an HDMI one that it
> >> supports an audio sink. However, strictly speaking, this is exposed as a
> >> separate part of EDID.
> >>
> >> This can be checked through the drm_detect_monitor_audio function, so let's
> >> use it and make sure that we can use the HDMI monitor as an output before
> >> sending sound.
> >
> > does the audio output work in the following setup after applying this patch?
> >
> > VC4 --- HDMI Audio extractor --- Non audio capable monitor
> 
> A 1-minute google of audio extractors says they manage the EDID.  Do you
> have some reason to think this wouldn't work?

My only concern is the existence of some audio extractors which doesn't care about EDID. I that case we need to provide some kind of force switch.