Re: [LAU] Error enabling dmix with ALSA

Hi,
Thanks for the quick response.

I had come across that thread when I goggled for a solution. As you have
suggested I have subscribed and posted this issue to alsa-devel mailing
list.

In the meanwhile, I would like to figure out the exact cause/source of the
error so that I can isolate this issue. Does this error occur due to some
invalid configuration file or setup with ALSA? or Is it a
hardware/driver/kernel specific issue?

Also, could someone point me to some documentation which explains the timer
setup and its usage in ALSA.

Thanks and Regards,

Ruchi.

On Sat, Aug 15, 2009 at 7:31 PM, Patrick Shirkey <pshirkey@email-addr-hidden
> wrote:

>
> On 08/15/2009 11:06 PM, ruchi sirauthiya wrote:
>
> 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
>
>
> According to this thread the drivers can't open a second timer on your
> device.
>
> http://osdir.com/ml/linux.distributions.crux.general/2005-11/msg00134.html
>
>
> Probably best to contact alsa-dev directly on this one.
>
>
> Warmest regards.
>
> Patrick Shirkey
> Boost Hardware Ltd
>
>
>
>
>
>
> 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:
> http://amarok.kde.org/wiki/Setting_up_Dmix_for_ALSA
>
> # 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@email-addr-hidden tests]# cat /proc/asound/version
> Advanced Linux Sound Architecture Driver Version 1.0.19
>
>
> [root@email-addr-hidden tests]# cat /proc/asound/cards
> 0 [omap3evm ]: twl4030 - omap3evm
> omap3evm (twl4030)
>
> [root@email-addr-hidden tests]# omap-dss: Could not find exact pixel clock. Requested
> 25188 kHz, got 25187 kHz
>
> [root@email-addr-hidden tests]# cat /proc/asound/devices
> 2: : timer
> 3: [ 0- 0]: digital audio playback
> 4: [ 0- 0]: digital audio capture
> 5: [ 0] : control
>
> [root@email-addr-hidden 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@email-addr-hidden tests]# cat /proc/asound/pcm
> 00-00: TWL4030 twl4030-0 : : playback 1 : capture 1
>
> [root@email-addr-hidden tests]# cat /proc/asound/devices
> 2: : timer
> 3: [ 0- 0]: digital audio playback
> 4: [ 0- 0]: digital audio capture
> 5: [ 0] : control
>
> [root@email-addr-hidden tests]# cat /proc/asound/pcm
> 00-00: TWL4030 twl4030-0 : : playback 1 : capture 1
>
> [root@email-addr-hidden tests]# cat /proc/asound/oss/devices
> 3: [0- 0]: digital audio
> 4: [0- 0]: digital audio
>
> [root@email-addr-hidden 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@email-addr-hidden 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@email-addr-hidden tests]# cat /proc/asound/devices
> 2: : timer
> 3: [ 0- 0]: digital audio playback
> 4: [ 0- 0]: digital audio capture
> 5: [ 0] : control
>
> [root@email-addr-hidden tests]# cat /proc/asound/pcm
> 00-00: OMAP PCM : omap alsa pcm : playback 1 : capture 1
>
> [root@email-addr-hidden 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@email-addr-hidden 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@email-addr-hidden 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.
>
> ------------------------------
>
> _______________________________________________
> Linux-audio-user mailing listLinux-audio-user@email-addr-hidden://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
>
>

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Received on Sun Aug 16 20:15:03 2009