On Wed, Apr 17, 2013 at 04:43:06PM +0800, Shawn Guo wrote:
> 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.
For purpose of debugging, the mxs audio can just work as before with the
changes below.
Shawn
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index ae0c37e..7d41fdd 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -148,6 +148,9 @@ static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
if (!substream)
continue;
+ if (i == SNDRV_PCM_STREAM_CAPTURE)
+ pcm->chan[i] = pcm->chan[SNDRV_PCM_STREAM_PLAYBACK];
+
if (!pcm->chan[i] && pcm->compat) {
pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
substream);