[pulseaudio-discuss] 0.9.8 - Invalid value for card

[Jim Duda]

Lennart,

aplay -c 6 -f S16_LE -r 44100 -v -D a52encode < /dev/urandom

works great, I get noise out of all 6 speakers via spdif and my AC3/DTS 
audio decoder.  Also, in this case, I didn't have to throw any switches 
in alsamixer to get the sound out.

It would be wonderful if I could get pulseaudio attached to a52encode.
This way, I wouldn't need ac3 passthrough, I would just convert ac3 to 6 
channel through pulse and route back through a52 to my external decoder.

However, device=a52encode in default.pa results in:

lroom# pulseaudio --system -v
I: core-util.c: Successfully gained nice level -11.
I: main.c: Found user 'pulse' (UID 499) and group 'pulse' (GID 499).
I: main.c: Successfully dropped root privileges.
W: main.c: setrlimit(RLIMIT_NICE, (31, 31)) failed: Operation not permitted
W: main.c: setrlimit(RLIMIT_RTPRIO, (9, 9)) failed: Operation not permitted
I: main.c: Page size is 4096 bytes
I: main.c: Dude, your kernel stinks! The chef's recommendation today is 
Linux with high-resolution timers enabled!
ALSA lib conf.c:3949:(snd_config_expand) Unknown parameters {AES0 0x6 
AES1 0x82 AES2 0x0 AES3 0x2 }
ALSA lib pcm.c:2145:(snd_pcm_open_noupdate) Unknown PCM iec958:{AES0 0x6 
AES1 0x82 AES2 0x0 AES3 0x2 }
E: alsa-util.c: Error opening PCM device a52encode: Invalid argument
E: module.c: Failed to load  module "module-alsa-sink" (argument: 
"device=a52encode"): initialization failed.
E: main.c: Module load failed.
E: main.c: failed to initialize daemon.
I: main.c: Daemon terminated.

I upgraded to 0.9.8 via an upgrade to fedora 8.  WHich uses alsa-lib 1.0.15

alsa-lib.i386                            1.0.15-1.fc8 
installed
alsa-lib-devel.i386                      1.0.15-1.fc8 
installed
alsa-oss.i386                            1.0.14-3.fc8 
installed
alsa-oss-devel.i386                      1.0.14-3.fc8 
installed
alsa-oss-libs.i386                       1.0.14-3.fc8 
installed
alsa-plugins-jack.i386                   1.0.15-2.fc8 
installed
alsa-plugins-oss.i386                    1.0.15-2.fc8 
installed
alsa-plugins-pulseaudio.i386             1.0.15-2.fc8 
installed
alsa-plugins-samplerate.i386             1.0.15-2.fc8 
installed
alsa-plugins-upmix.i386                  1.0.15-2.fc8 
installed
alsa-plugins-vdownmix.i386               1.0.15-2.fc8 
installed
alsa-tools.i386                          1.0.12-4.fc7 
installed
alsa-utils.i386                          1.0.15-1.fc8 
installed
a


Jim

Lennart Poettering wrote:
> On Thu, 27.03.08 13:27, Jim Duda (jim at duda.tzo.com) wrote:
> 
>> Yes, I do understand that I can only get PCM stereo through the spdif using pulseaudio at this time (no AC3/DTS).
>>
>> My understanding (from reading all the posts) is that it's really a flaw with ALSA, which pulseaudio doesn't have a 
>> means to resolve (poor API with alsa spdif support).
>>
>> I really would love pulseaudio with AC3/DTS passthrough, but I understand we don't have it yet.
>>
>> I'm really just playing with stereo support through spdif at this time.
>>
>> What might be a useful interim solution is to use the alsa a52 encoder.
>>
>>
>> The alsa a52 encoder will take a 6 channel "analog" audio source and encode it to a52 digital and then route out the 
>> spdif port.  It has worked very well for me to upmix 2 channel stereo to 6 channel a52.
>>
>> In .asoundrc, I have:
>>
>> pcm.a52encode {
>>     type a52
>> }
> 
> My recommendation: first try to get alsa to work, than make PA work on
> top of it. Try testing your a52 device with aplay first:
> 
>   aplay -c 6 -f S16_LE -r 44100 -v -D a52encode < /dev/urandom
> 
> If this doesn't work, then please contact the ALSA guys. 
> 
> Lennart
>