ASoC: dmaengine-pcm: Make requesting the DMA channel at PCM open optional

Refactor the dmaengine PCM library to allow the DMA channel to be requested
before opening a PCM substream. snd_dmaengine_pcm_open() now expects a DMA
channel instead of a filter function and filter parameter as its parameters.
snd_dmaengine_pcm_close() is updated to not release the DMA channel. This allows
a dmaengine based PCM driver to request its channels before the substream is
opened.

The patch also introduces two new functions, snd_dmaengine_pcm_open_request_chan()
and snd_dmaengine_pcm_close_release_chan(), which have the same signature and
behaviour of the old snd_dmaengine_pcm_{open,close}() and internally use the new
variants of these functions. All users of snd_dmaengine_pcm_{open,close}() are
updated to use snd_dmaengine_pcm_open_request_chan() and
snd_dmaengine_pcm_close_release_chan().

Signed-off-by: Lars-Peter Clausen <[email protected]>
Tested-by: Stephen Warren <[email protected]>
Tested-by: Shawn Guo <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
This commit is contained in:
Lars-Peter Clausen 2013-04-15 19:19:48 +02:00 • committed by Mark Brown
commit 7c1c1d4a7b
11 changed files with 78 additions and 44 deletions

View file

@ -39,9 +39,13 @@ snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);
int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
dma_filter_fn filter_fn, void *filter_data);
struct dma_chan *chan);
int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
dma_filter_fn filter_fn, void *filter_data);
int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
/**