[pulseaudio-discuss] [RFC] Alsa UCM integration.

[Liam Girdwood]

On Fri, 2011-02-25 at 10:10 -0600, pl bossart wrote:
> > Modifiers can be used in the following situations:-
> >
> > 1) Music is being played. Pulseaudio has configured the Music use case
> > verb via UCM. The system wants to play a tone, this could be a beep or
> > even a ring tone for an incoming call. Pulseaudio would then check for a
> > UCM "play tone" modifier for the current verb and then enable the
> > modifier if it exists. This "play tone" modifier would setup the
> > hardware to play both Music (i.e the verb) and additionally tones (the
> > modifier). The modifier may use a different ALSA pcm and hardware volume
> > controls to that of the main verb.
> >
> > If no "play tone" modifier exists then Pulsewould mix the tone into the
> > music being played in software as it does atm.
> >
> > 2) Phone call is in progress. Pulseaudio has enabled the phone call UCM
> > verb. The user wants to play music on the phone call. The modifier would
> > be "Music" so Pulseaudio will check that a modifier exist for this when
> > the phone call verb is active and enable this modifier.
> >
> > If no music modifier is available in the phone call verb configuration
> > then pulseaudio would mix the music and voice in software.
> 
> Make sense.
> But I am not sure the profiles as defined today in PulseAudio can work
> with modifiers. What we discussed yesterday is that when a profile is
> selected then you would set the UCM verb and know about all possible
> sinks. We would need additional logic to have profile modifiers, or we
> would need extra profiles to represent all possible combinations
> (speech, speech+tone, speech+music, etc).

Yeah, I'm thinking it may be easier to add the extra profiles here. We
could match a profile and it's UCM verb+modifier at init time.

Liam