Re: [RFC PATCH] ARM ASoC: add sound driver for imx27pdk using mc13783 codec

["Lambrecht Jürgen" <J.Lambrecht@TELEVIC.com>]

On 07/08/2011 04:11 PM, Philippe Rétornaz wrote:
>
> Le vendredi 8 juillet 2011 15:24:51, Jürgen Lambrecht a écrit :
> > - Started from sound/soc/imx/phycore-mc13783.c
> > - Renamed to general "imx" because also valid for imx27pdk (3ds) and 
> other
> > 3ds platforms. Or should there be a file per platform?
>
> It's also valid on the mx31moboard platforms. So I guess it make sens 
> to have
> a general name.
>
ok
>
> > - Fixed some issues (add names, add read/write functions, changed
> > late_initcall to module_init, configure clock input pin) - Add debug
> > printing and comments.
> > - Result:
> >   * soundcard detection;
> >   * after creating /dev entries, aplay runs;
> >   * both 'aplay song.wav' and 'madplay song.mp3' give the same error:
> >     a time-out waiting for DMA (ALSA pcm_lib.c:1802: playback write 
> error
> > (DMA or IRQ trouble?)) * this driver uses the DMA method; the FIQ method
> > gives the same error
>
> Does it mean this doesn't work at all to play sound ? IIRC Sascha 
> driver used
> to work with the non-dmaengine implementation on 2.6.34.
>
indeed, doesn't work at all. I know it used to work on 2.6.34.
We also have a fsl linux 2.6.22 were it works.
I must say: when i use aplay to play a mono file, then there is no 
error, it just never ends, and no sound also.
For a stereo file, it gives the error.
Mark also that when I use madplay (v0.15.2) (or mp3play) to play a mono 
or stereo mp3, it allocates 3 DMA channels, but only frees one after the 
error.

Jürgen
>
>
> Thanks,
>
> Philippe
>


-- 
Jürgen Lambrecht
R&D Associate
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