[alsa-devel] [PATCH 10/17] ASoC: mxs: Use generic dmaengine PCM

[Shawn Guo]

On Mon, Apr 15, 2013 at 07:19:57PM +0200, Lars-Peter Clausen wrote:
> Use the generic dmaengine PCM driver instead of a custom implementation.
> 
> Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
> ---
>  sound/soc/mxs/Kconfig   |   2 +-
>  sound/soc/mxs/mxs-pcm.c | 135 ++++--------------------------------------------
>  2 files changed, 11 insertions(+), 126 deletions(-)

After applying the patch, mxs audio is broken as below.

[    2.003200] mxs-saif 80042000.saif: Missing dma channel for stream: 1
[    2.010220] mmc0: new high speed SDHC card at address e624
[    2.016453] mxs-saif 80042000.saif: ASoC: pcm constructor failed: -22
[    2.022964] mxs-sgtl5000 sound.12: ASoC: can't create pcm HiFi Playback :-22
[    2.030310] mxs-sgtl5000 sound.12: ASoC: failed to instantiate card -22

It's caused by that dmaengine_pcm_new() will call
dmaengine_pcm_compat_request_channel() twice to request the same mxs-dma
channel, and the second call will fail.

Shawn