From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: Looking for help with dmix plug-in on ARM Date: Fri, 09 Feb 2007 13:06:39 +0100 Message-ID: References: <15711510.1170960250793.JavaMail.root@fed1wml07.mgt.cox.net> Mime-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <15711510.1170960250793.JavaMail.root@fed1wml07.mgt.cox.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@lists.sourceforge.net Errors-To: alsa-devel-bounces@lists.sourceforge.net To: daniel.car@cox.net Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Thu, 8 Feb 2007 10:44:10 -0800, wrote: > > Hi, > > I'm working on an unannounced SOC audio driver on an ARM system. I have a problem were audio works fine with out dmix, but when I try to use dmix no audio data gets to the driver. The dmix plug-in does work when attaching external usb audio device. Trying to use dmix so that more then one application can generate audio simultaneously. > > If I try with version 1.0.11 of ALSA the audio driver doesn't receive any data after the snd_pcm_period_elapsed() function call. If I try with version 1.0.13 of ALSA, aplay returns an error saying: > # aplay -D hw:0,0 pcm48khz_2ch_stereo.wav open_stream success > Playing WAVE 'pcm48khz_2ch_stereo.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Stereo > aplay: set_params:882: Broken configuration for this PCM: no configurations available > > I'm planning on building a debug version of 1.0.14rc2 and tracing thru the code to see why aplay fails. Is there a better way to debug this? Are there any tricks for building ALSA with debug info? So, actually it's a problem of driver / alsa-lib hw layer rather than dmix? You can get more verbose messages by setting LIBASOUND_DEBUG variable. See alsa-lib/NOTES for details. > Here is how the driver is set up: > static snd_pcm_hardware_t snd_oloriver_playback_hw = { > .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | > SNDRV_PCM_INFO_MMAP_VALID), > .formats = SNDRV_PCM_FMTBIT_S16_LE, > .rates = SNDRV_PCM_RATE_48000, > .rate_min = 48000, > .rate_max = 48000, > .channels_min = 2, > .channels_max = 2, > .buffer_bytes_max = 65536, > .period_bytes_min = 32768, > .period_bytes_max = 32768, > .periods_min = 2, > .periods_max = 2, My rough guess is that the buffer and period size constraints are too restrictive. You can try to pass the exact period/buffer sizes to aplay via --period-size=8192 --buffer-size=16384 options. Takashi ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier. Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642