Hello

I am working towards using ALSA for playback and capture on an embedded 
platform running Linux. The kernel uses ALSA driver version 1.0.10rc1. I had 
manually built and installed ALSA library (v1.0.10) and ALSA utilities 
(v1.0.10) for the target platform filesystem. I have a USB audio device 
(C-Media) connected to the USB port of the board and it seems to be 
successfully successfully detected by the driver.

~ # ls /dev/snd -l
crw-rw----    1 root     root     220,   0 Jan  1 00:00 controlC0
crw-rw----    1 root     root     220,  24 Jan  1 00:00 pcmC0D0c
crw-rw----    1 root     root     220,  16 Jan  1 00:00 pcmC0D0p
crw-rw----    1 root     root     220,   1 Jan  1 00:00 seq
crw-rw----    1 root     root     220,  33 Jan  1 00:00 timer


~ # cat /proc/asound/cards
0 [default        ]: USB-Audio - C-Media USB Audio Device
                     C-Media USB Audio Device    at usb-asic-ehci-1.4, full 
speed

~ # cat /proc/asound/devices
  1:       : sequencer
 16: [0- 0]: digital audio playback
 24: [0- 0]: digital audio capture
  0: [0- 0]: ctl
 33:       : timer

~ # cat /proc/asound/card0/stream0
C-Media USB Audio Device    at usb-asic-ehci-1.4, full speed : USB Audio

Playback:
  Status: Stop
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 48000, 44100

Capture:
  Status: Stop
  Interface 2
    Altset 1
    Format: S16_LE
    Channels: 1
    Endpoint: 2 IN (ASYNC)
    Rates: 48000, 44100


However, when I run ALSA utilities like aplay, arecord or speaker-test, I 
observe errors opening the hardware device which may be related to the 
configuration on the filesystem.

~ # aplay -l
**** List of PLAYBACK Hardware Devices ****
ALSA lib control.c:817:(snd_ctl_open_noupdate) Invalid CTL hw:0
aplay: device_list:230: control open (0): No such file or directory
aplay: conf.c:3109: snd_config_update_free: Assertion `update->count > 0 && 
update->finfo' failed.
Aborted (core dumped)
~ #

/home/saurav # aplay -D plughw:0,0 winxp.wav
ALSA lib pcm.c:2099:(snd_pcm_open_noupdate) Unknown PCM plughw:0,0
aplay: main:544: audio open error: No such file or directory
/home/saurav #
/home/saurav #
/home/saurav # speaker-test

speaker-test 0.0.8

Playback device is plughw:0,0
Stream parameters are 48000Hz, S16_BE, 1 channels
Using 16 octaves of pink noise
ALSA lib pcm.c:2099:(snd_pcm_open_noupdate) Unknown PCM plughw:0,0
Playback open error: -2,No such file or directory
speaker-test: conf.c:3109: snd_config_update_free: Assertion `update->count > 0 
&& update->finfo' failed.
Aborted (core dumped)
/home/saurav #

Are these errors from ALSA utility/library due to the detection of hardware, 
ALSA configuration files or something else related to my target device 
filesystem?

Thanks in advance for any help. Do let me know if you need any more details.

Best Regards
Saurav
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Alsa-user mailing list
Alsa-user@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/alsa-user

Reply via email to