[alsa-devel] ALSA : Can't open capture device
cladisch at fastmail.net
Fri Jan 11 14:16:54 CET 2008
Alexandre BOUIN wrote:
> I'm working on an intern project, using an AT91SAM9260EK-based board,
> embedded system.
> Our kernel contains a full ALSA 1.14 with ASoC layer.
> Our ASoC driver works well in capture and playback, if we are using OSS
> layer or directly /dev/dsp.
> So I need some tips on ALSA layer side :
> here you can see that my device is created :
> ll /dev/snd/
> crwxrwxrwx 1 root root 116, 0 Dec 26 2007 controlC0
> crwxrwxrwx 1 root root 116, 4 Dec 26 2007 hwC0D0
> crwxrwxrwx 1 root root 116, 14 Dec 26 2007 pcmC0D0c
> crwxrwxrwx 1 root root 116, 16 Dec 26 2007 pcmC0D0p
> ll /dev/dsp
> crwxrwxrwx 1 root root 14, 3 Dec 26 2007 /dev/dsp
> A cat on playback device works (I added some traces in kernel) :
> cat < /dev/snd/pcmC0D0p
> snd_pcm_open : enter
> snd_pcm_open_file : before snd_pcm_open_substream
> snd_pcm_open_file : after snd_pcm_open_substream
> cat: read error: Invalid argument
> But a cat on capture device does not work :
> cat < /dev/snd/pcmC0D0c
> -sh: cannot open /dev/snd/pcmC0D0c: No such device
Does the capture device appear in /proc/asound/devices or in the output
of "arecord -l"?
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