[alsa-devel] Problem opening default device in haswell system using aplay
stefano.panella at citrix.com
Tue May 28 11:26:09 CEST 2013
On 05/27/2013 08:07 AM, Takashi Iwai wrote:
> At Wed, 22 May 2013 16:48:58 +0100,
> Stefano Panella wrote:
>> Hi everyone,
>> sorry if this email has been sent twice... ( I sent it once before subscribing)
>> I am working on some haswell systems running Ubuntu 12.04 and I have a problem if I run aplay -D sysdefault.
>> when I do:
>> cat /proc/asound/pcm
>> I get:
>> 00-03: HDMI 0 : HDMI 0 : playback 1
>> 00-07: HDMI 1 : HDMI 1 : playback 1
>> 00-08: HDMI 2 : HDMI 2 : playback 1
>> 01-00: ALC662 rev3 Analog : ALC662 rev3 Analog : playback 1 : capture 1
>> 01-02: ALC662 rev3 Analog : ALC662 rev3 Analog : capture 1
>> If I do:
>> aplay -L | grep sysdefault
>> I get:
>> where PCH is card number 1 (id = 1)
>> on most of my systems (non haswell laptops) the default card is number 0
>> If I run
>> aplay -D sysdefault
>> I get:
>> ALSA lib pcm_dmix.c:1018:(snd_pcm_dmix_open) unable to open slave
>> aplay: main:682: audio open error: No such file or directory
> It's because the card 0 contains only HDMI. The sysdefault in
> HDA-Intel.conf is configured for the analog I/O.
Thanks for answering, what I do not get is what the default
configuration is on a freshly installed system (no custom configurations):
- for example, can I assume hw:0,0 is always there and is the default?
(apparently not on these haswell machine)
- if I run aplay -D sysdefault is it expected to work?
- is there any ALSA_CARD variable configured somewhere or is it just
supposed to be 0?
- how do I know what is it the default card/pcm?
The reasons I am asking these questions is I need to write some SW which
will be able to open the default analog playback device and on haswell
system I did not find any way to do that apart from using:
aplay -L | grep sysdefault
which will return <CARD> = PCH or Intel or MID etc.. and than I open
hw:<CARD>,0 from the C code.
I would like to understand if I can poerform some more tests to
understand if this is a genuine problem on haswell systems or if I am
just making some wrong assumptions or incorrect use of the cmd_line/API.
Thanks again for helping me on this.
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