[alsa-devel] SALSA-Lib: snd_pcm_hw_params fails with MMAP

[Takashi Iwai]

At Mon, 02 Jul 2007 15:25:05 +0200,
I wrote:
> 
> At Sat, 30 Jun 2007 16:23:38 -0400,
> J. Scott Merritt wrote:
> > 
> > Dear List,
> > 
> > Using SALSA-Lib 0.0.5 ...
> > 
> > After calling snd_pcm_hw_params_set_access with an access mode of
> > SND_PCM_ACCESS_MMAP_INTERLEAVED, the subsequent call to snd_pcm_hw_params
> > returns a snd_strerror error code of "Invalid argument".
> > 
> > This same program operates properly in the target environment (ARM PXA270)
> > when compiled and linked with the standard ALSA LIB 1.0.13.
> 
> Don't use mmap mode.  It seems not supported well.

More words on MMAP:  The snd_pcm_mmap_read/write*() are unsupported
anyway, so it's no go if you used it.

Except for that, the _normal_ mmap using mmap-begin, commit,
avail_update should work.  The mmap-hw_params bug should have been
fixed in version 0.0.6 release.


Takashi