[pulseaudio-discuss] Emulate Alsa A52 plugin in pulseaudio ?

[Jim Duda]

Tanu,

Aha, I'm getting closer.  I realized that I cannot open the hardware twice.

If I do this:

load-module module-alsa-sink sink_name=ac3_raw device=spdif:0
load-module module-alsa-sink sink_name=ac3_encode device=a52encode

I get an error on the second alsa-sink for a52encode, since ac3_raw already has the device.

If I do this:

#load-module module-alsa-sink sink_name=ac3_raw device=spdif:0
load-module module-alsa-sink sink_name=ac3_encode device=a52encode

The a52encode appears to start:

*** Module #0 ***
Name: module-alsa-sink
Argument: sink_name=ac3_encode device=a52encode
Usage counter: n/a
Auto unload: no

Unfortunately, pulseaudio crashes after pactl list :-(

I am having fun though :-)

Jim




"Jim Duda" <jim at duda.tzo.com> wrote in message news:fq9b8k$s4r$1 at ger.gmane.org...
>I think I've learned that in order for a52encode to possibly work, I need to have /var/run/pulse/.asoundrc defined.
>
> /var/run/pulse/.asoundrc:
>
> pcm.a52encode {
>     type a52
> }
>
> Yields:
>
> lroom# /usr/bin/pulseaudio --system
> E: module-alsa-sink.c: Error opening PCM device a52encode: Device or resource busy
> E: module.c: Failed to load  module "module-alsa-sink" (argument: "sink_name=ac3_encode device=a52encode rate=48000 
> channels=6"): initialization failed.
> E: main.c: Module load failed.
> E: main.c: failed to initialize daemon.
>
> If I change a52encode to something else in the .asoundrc, I get:
>
> E: module-alsa-sink.c: Error opening PCM device a52encode: No such file or directory
> E: module.c: Failed to load  module "module-alsa-sink" (argument: "sink_name=ac3_encode device=a52encode rate=48000 
> channels=6"): initialization failed.
> E: main.c: Module load failed.
> E: main.c: failed to initialize daemon.
>
> So, apparently the .asoundrc in /var/run/pulse is recognized.
>
> Using a52encode:0 results in:
>
> lroom# /usr/bin/pulseaudio --system
> ALSA lib conf.c:3949:(snd_config_expand) Unknown parameters 0
> ALSA lib pcm.c:2144:(snd_pcm_open_noupdate) Unknown PCM a52encode:0
> E: module-alsa-sink.c: Error opening PCM device a52encode:0: Invalid argument
> E: module.c: Failed to load  module "module-alsa-sink" (argument: "sink_name=ac3_encode device=a52encode:0 rate=48000 
> channels=6"): initialization failed.
> E: main.c: Module load failed.
> E: main.c: failed to initialize daemon.
>
> Some permission problem maybe ....
>
> Thanks for listening :-)
>
> Jim
>
>
> "Tanu Kaskinen" <tanuk at iki.fi> wrote in message news:20080229054425.GB12761 at a9a.mannikko1.tontut.fi...
>> On Thu, Feb 28, 2008 at 09:36:20PM -0500, Jim Duda wrote:
>>> Unfortunately, using a52encode as a device doesn't seem to work.  I
>>> tried by a52encode and a52.
>>>
>>> lroom# /usr/bin/pulseaudio --system
>>> ALSA lib control.c:909:(snd_ctl_open_noupdate) Invalid CTL surround51:0
>>> W: alsa-util.c: Unable to attach to mixer surround51:0: No such file or
>>> directory
>>> ALSA lib pcm.c:2144:(snd_pcm_open_noupdate) Unknown PCM a52encode
>>> E: module-alsa-sink.c: Error opening PCM device a52encode: No such file
>>> or directory
>>
>> Which file doesn't exist?
>> "strace -f pulseaudio --system > strace.out 2>&1" should
>> give the answer. Before running that I'd check if changing
>> a52encode:0 to just a52encode would help. The :0 part
>> identifies the card and I think a52encode isn't associated
>> with any specific card.
>>
>> Since I don't know much about the a52 plugin, I really am
>> not sure that pulseaudio can use it at all.
>>
>> -- 
>> Tanu Kaskinen