[alsa-devel] [PATCH v3 14/15] ASoC: hdac_hdmi: Add jack reporting for user space

[Takashi Iwai]

On Tue, 08 Dec 2015 11:42:57 +0100,
Vinod Koul wrote:
> 
> On Tue, Dec 08, 2015 at 11:28:16AM +0100, Takashi Iwai wrote:
> > > Yes that was my thinking based on discussion and patches posted by Libin.
> > > But one more question who does PCM assignment, looking at patches it seems
> > > driver and no way to change that..
> > > 
> > > For example I have 10 devices connected  and we have 5 PCMs.
> > > I would like to route to 7th device, how would that be done?
> > 
> > Manage xrandr to enable the target monitor.  Then one PCM stream will
> > be switched to the corresponding audio, and it'll be notified to
> > user-space.
> 
> Thanks, that helps..
> 
> Looking at RFC patches I do not see that implemented, so maybe Libin
> and you will add that eventually
> 
> The question here is how will the switch be handled, can you please
> elaborate on that. From xrandr selection how will audio driver be
> notified and how will change be done?

The switch itself has to be done voluntarily by user-space,
unfortunately, as in the current form.  We thought of the preemptive
disconnection.  It works for aplay, but screws up PulseAudio, so
no-go.


Takashi