[alsa-devel] MCP7A HDMI passthrough audio Linux/ALSA
tiwai at suse.de
Wed Jul 1 08:18:22 CEST 2009
At Tue, 30 Jun 2009 22:51:03 +0200,
Stephane BERTHELOT wrote:
> Takashi Iwai a écrit :
> At Tue, 30 Jun 2009 15:04:05 +0200,
> Stéphane BERTHELOT wrote:
> Hi Takashi,
> Thanks for you answer.
> I have the exact same problem and configuration than reported here
> apart :
> - I'm using a ION platform (Acer Revo R3600 but still MCP7A : 0x10de0007)
> - I never get the Dolby Digital or DTS indicator illuminated on my Amp.
> - My TV is a Sharp LC-52X20E
> I thought this was a known problem and than someone at Nvidia could
> provide the missing HDA Verbs, if you prefer I can post to the
> alsa-devel mailing list to investigate further.
> I can get a alsa-info output tonight, though it's very very similar to
> the one in the bug report. (and Raymond was saying that we should get
> "PCM AC3" on digital outputs)
> Try ac3dec for a primary testing instead of mplayer. It's included in
> % ac3dec -C -H foo.ac3
> Use the latest one so that it accespt -H option.
> Thank you Takashi for taking time to review my problem. I cc'ed alsa-devel
> since I have more info now and maybe some other people have the same problem
> or already a workaround.
> I'm attaching the output of alsa-info.sh with my mixer settings and after
> having run ac3dec -H -C file.ac3
> It works with -R instead of -C but does not work with -C or with -P (consumer
> or pro)
> I also tried modifying settings using iecset (audio off / audio on and
> consumer/pro) and no combination seems to work.
> When I play stereo LPCM my TV set plays sound and so does my Amp in PCM mode.
> When I try to play in AC3 mode (-C) my TV set says "incompatible format
> received" and both the TV and Amp stay silent.
Hm, so apparently your TV doesn't accept non-audio format?
But TV accepted the ac3dec output with -R option, right?
(Make sure this -- otherwise ac3dec might have decoded by itself.)
Basically, -R means to send the encoded an AC3 stream (packed in the
SPDIF format) without setting non-audio bit. Whether non-audio bit is
1 or 0 is the only difference between -C and -R. So, if -R really
works but not -C, it means that the non-audio bit must be off no
matter what you send. Weird.
> I may try again on XP/Vista tomorrow to be really sure it works on them.
> When changing play mode AES0 changes from 0x00 to 0x02 and AES1 to AES3 stay
> the same (0x82,0x00,0x02 if I remember well)
Note that the setup you made before ac3dec will be overridden anyway.
And during ac3dec playback, the status bits are locked and can't be
changed by others.
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