Hi,
I am trying to enable a software mixer (using ALSA and dmix) on an OMAP3 based embedded target board using the twl4030 codec.
When I try to play audio using the command,
# aplay -D playback rec.wav
I am getting the following error:
ALSA lib pcm_direct.c:1098:(snd_pcm_direct_initialize_poll_fd) unable to
open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:943:(snd_pcm_dmix_open) unable to initialize poll_fd
aplay: main:546: audio open error: No such file or directory
The contents of my /etc/asound.conf is given below.
pcm.playback {
type dmix
ipc_key 2048
ipc_key_add_uid true
ipc_gid 1
slave {
rate 44100
pcm hw:0
}
}
I have tested it on two kernel versions, 2.6.22 and 2.6.29, but it fails on both.
Playback and recording works fine if -D option is not provided.
I also tried configuring ALSA (dmix) with a different configuration file which is given in the following link:
# aplay -D plug:ossmix /mnt/Audio1_1.wav
ALSA lib pcm_direct.c:1098:(snd_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:943:(snd_pcm_dmix_open) unable to initialize poll_fd
aplay: main:546: audio open error: No such file or directory
But as you can see the same error turns up again.
What could be the cause of this error?
Is the above error related to ALSA configuration (for dmix)?
Do I need to patch the kernel or ALSA for using dmix?
Please help me resolve this issue. Let me know if any more setup info is required.
Thanks and Regards,
Ruchi Sirauthiya.
Some information I obtained from the proc filesystem is given below for your reference.
-----------------------
For Linux kernel 2.6.29
-----------------------
[root@OMAP3 tests]# cat /proc/asound/version
Advanced Linux Sound Architecture Driver Version 1.0.19
[root@OMAP3 tests]# cat /proc/asound/cards
0 [omap3evm ]: twl4030 - omap3evm
omap3evm (twl4030)
[root@OMAP3 tests]# omap-dss: Could not find exact pixel clock. Requested 25188 kHz, got 25187 kHz
[root@OMAP3 tests]# cat /proc/asound/devices
2: : timer
3: [ 0- 0]: digital audio playback
4: [ 0- 0]: digital audio capture
5: [ 0] : control
[root@OMAP3 tests]# cat /proc/asound/timers
G0: system timer : 7812.500us (10000000 ticks)
P0-0-0: PCM playback 0-0-0 : SLAVE
P0-0-1: PCM capture 0-0-1 : SLAVE
[root@OMAP3 tests]# cat /proc/asound/pcm
00-00: TWL4030 twl4030-0 : : playback 1 : capture 1
[root@OMAP3 tests]# cat /proc/asound/devices
2: : timer
3: [ 0- 0]: digital audio playback
4: [ 0- 0]: digital audio capture
5: [ 0] : control
[root@OMAP3 tests]# cat /proc/asound/pcm
00-00: TWL4030 twl4030-0 : : playback 1 : capture 1
[root@OMAP3 tests]# cat /proc/asound/oss/devices
3: [0- 0]: digital audio
4: [0- 0]: digital audio
[root@OMAP3 tests]# cat /proc/asound/oss/sndstat
Sound Driver:3.8.1a-980706 (ALSA v1.0.19 emulation code)
Kernel: Linux OMAP3 2.6.29-rc3-omap1 #1 Fri Jul 24 14:45:37 IST 2009 armv7l
Config options: 0
Installed drivers:
Type 10: ALSA emulation
Card config:
omap3evm (twl4030)
Audio devices:
0: (DUPLEX)
Synth devices: NOT ENABLED IN CONFIG
Midi devices: NOT ENABLED IN CONFIG
Timers:
31: system timer
Mixers: NOT ENABLED IN CONFIG
[root@OMAP3 tests]# aplay -D playback /mnt/Audio1_1.wav
ALSA lib pcm_direct.c:1098:(snd_pcm_direct_initialize_poll_fd) unable to open timer 'hw:CLASS=3,SCLASS=0,CARD=0,DEV=0,SUBDEV=0'
ALSA lib pcm_dmix.c:943:(snd_pcm_dmix_open) unable to initialize poll_fd
aplay: main:546: audio open error: No such file or directory
-----------------------
For Linux kernel 2.6.22
-----------------------
[root@OMAP3 tests]# cat /proc/asound/devices
2: : timer
3: [ 0- 0]: digital audio playback
4: [ 0- 0]: digital audio capture
5: [ 0] : control
[root@OMAP3 tests]# cat /proc/asound/pcm
00-00: OMAP PCM : omap alsa pcm : playback 1 : capture 1
[root@OMAP3 tests]# cat /proc/asound/timers
G0: system timer : 7812.500us (10000000 ticks)
P0-0-0: PCM playback 0-0-0 : SLAVE
P0-0-1: PCM capture 0-0-1 : SLAVE
[root@OMAP3 tests]# cat /proc/asound/
/proc/asound/TWL4030/ /proc/asound/devices /proc/asound/timers
/proc/asound/card0/ /proc/asound/hwdep /proc/asound/version
/proc/asound/cards /proc/asound/pcm
[root@OMAP3 tests]# cat /proc/asound/cards
0 [TWL4030 ]: OMAP_ALSA - TWL4030
TWL4030
/proc/asound/oss was not found in the proc file system when booted with kernel 2.6.22.