[pulseaudio-discuss] PA UCM support (Volume and Jack)

[Felipe Tonello]

Hi Arun,

On Tue, Aug 6, 2013 at 11:11 AM, Arun Raghavan
<arun.raghavan at collabora.co.uk> wrote:
> On Tue, 2013-08-06 at 11:00 -0700, Felipe Tonello wrote:
>> Hi Arun,
>>
>> On Mon, Aug 5, 2013 at 8:43 PM, Arun Raghavan
>> <arun.raghavan at collabora.co.uk> wrote:
>> > On Mon, 2013-08-05 at 11:43 -0700, Felipe Tonello wrote:
>> >> Hi all,
>> >>
>> >> I'm using UCM configurations to handle multiple devices and
>> >> playback/capture mixer controls. It seems that PA UCM implementation
>> >> just store the PlaybackVolume PlaybackSwitch properties but doesn't
>> >> make any usage of it.
>> >>
>> >> What I want to do is basically to be able to change hardware volume
>> >> instead of just software volume. When I plug a Headphone, for
>> >> instance, I want PA to change the volume of the alsa control that I
>> >> specified by PlaybackVolume in the UCM file not just the sink volume.
>> >>
>> >> Is that possible to do? Does it require a patch or some work?
>> >
>> > It is possible of course, but hasn't been implemented (yet).
>>
>> I will probably need this use case. I hope to send a patch in a few
>> weeks to come.
>
> Excellent!
>
>> >
>> >> Also, jack support for UCM seems to have a bug. For when using UCM
>> >> support, when I start PA or change a card profile with a jack
>> >> previously plugged, it doesn't recognizes that unless I unplug and
>> >> plug again.
>> >
>> > David was looking into hooking up jack detection with UCM, so might have
>> > some more useful information for you.
>>
>> Actually I realized was probably a problem in my UCM configuration.
>> Now it seems to be ok.
>>
>> >
>> >> Any comments on that as well?
>> >>
>> >> OBS: I'm using PA 3.0.
>> >
>> > You'd also mentioned the problem with modem PCMs on IRC. I think we
>> > really don't have much choice here but to go with the
>> > PA_SINK_ALWAYS_RUNNING flag that I'd posted earlier, coupled with adding
>> > a field in the UCM to signal that this needs to be set.
>>
>> I saw your patch. It was not upstreamed right? Also, how would you set
>> that flag in run-time?
>
> Correct about the former (though I'll likely rebase and resubmit it at
> some point soon). As for applying it at run time, we could add a value
> known to PA in the UCM 'Value' section, and then have our UCM processing
> set the flag based on that.

Yes, that will be great. what I'm doing now, which is a terrible
workaround but I now is a temporary fix, is to don't stop writing to
the sink until the call is over. :)

Felipe Tonello