[alsa-devel] OSS app works but aplay does not with SNDRV_PCM_FMTBIT_U32_LE
cladisch at fastmail.net
Fri Sep 21 08:43:25 CEST 2007
Steve Strobel wrote:
> At 10:03 AM 9/19/2007, Clemens Ladisch wrote:
> >Steve Strobel wrote:
> > > At 12:46 AM 9/19/2007, Clemens Ladisch wrote:
> > > > or did you create a card-specific .conf file for your controller?
> > >
> > > Not intentionally, but there might be one left over from the AD1836
> > > driver I started with (I have just been modifying that driver,
> > > planning to rename it after I get it working). Where would I look
> > > for such a file?
> >In /usr/share/alsa/cards/, with the driver name.
> I don't have a file there; that directory doesn't even exist:
> Should I have a configuration file in one of those places? If I
> don't, where do the default values come from?
Well, there is an alsa.conf somewhere, otherwise the utils wouldn't run.
> >Does it work when running aplay with the parameter "-D plughw"?
> No. It searches through more rules, but still says, "Sample format
> non available". I put a log of the console output with and without
> "-D plughw" at <http://link-comm.com/temp/aplay-log.txt> to save
Now it says that access RW_INTERLEAVED doesn't work.
I'd really like to see the source code of the driver, especially the
> One thing I hadn't noticed before is the message:
> ALSA lib ../../../src/pcm/pcm_params.c:2152:(snd_pcm_hw_refine_slave) Slave PCM not usable
> refine done - result = -22
> Does a result code of -22 mean anything significant?
Nothing that hasn't been already been told in the error message.
-EINVAL is expected in this case.
> You wrote in an earlier message:> > snd_pcm_hw_refine()
> > > ACCESS = 00000000ffffffffffffffff -> 0000000000000008
> > > FORMAT = 0000000000000400 -> 0000000000000000
> > aplay tries to set S32_LE, but the driver doesn't accept it.
> I think I understand how the driver uses the snd_pcm_hardware_t
> structure to tell ALSA what it supports, but I don't understand how
> ALSA tries to set things in return. I am surprised that it would try
> to set it to a data type that the driver never said it could
A configuration file can force a specific sample format. Usually, only
dmix does that.
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