Re: [Qemu-devel] [PATCH v2 4/4] audio: paaudio: ability to specify stream name

[Maxim Levitsky <mlevitsk@redhat.com>]

On Wed, 2019-08-28 at 09:33 +0200, Gerd Hoffmann wrote:
> > > Hmm, can we create an useful name automatically, without yet another
> > > config option?
> > > 
> > > Useful choices could be the device name (usb-audio, ...) or the device
> > > id (whatever -device id=xxx was specified on the command line).
> > 
> > I'm afraid this is not going to work with the current architecture: due
> > to mixeng even if you have multiple devices, they'll be mixed to a
> > single stream and the audio backend will only see this one mixed stream.
> >  As a workaround we could do something like concat all device names or
> > ids, but I don't like that idea.
> > 
> > Alternatively we could use the id of the audiodev instead, and no more
> > problems with mixeng.  However, with mixeng off (implemented in my next
> > patch series) suddenly soundcards will have suddenly end up as different
> > streams.  (This can be worked around by creating multiple audiodevs,
> > like what you have to use now to get multiple streams from pa, so this
> > is probably a smaller problem.)
> > 
> > Currently I'm leaning for the audiodev's id option, unless someone
> > proposes something better.
> 
> Hmm, maybe just wait and see if we really need that?
> 
> If we use the vm name for the pa connection I suspect most use cases are
> covered ...

My personal opinion would be, to use vm name for the connection (will cover
use case of distinguishing between VMs)
and using audiodev derived name for stream names, which will at least
partially cover the use case of having more that one guestn's soundcard,
and assigning each to different host sound card dynamically,
that is  using pavucontrol, which is what I wanted to do in first place.
This is also should be the easiest to do probably.

Best regards,
	Maxim Levitsky