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ASoC: OMAP: Use McBSP threshold to playback and capture

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This patch changes the way DMA is done in omap-pcm.c
in order to reduce power consumption. There is no need
to have so much SW control in order to have DMA in idle
state during audio streaming. Configuring McBSP threshold value
and DMA to FRAME_SYNC are sufficient.

Signed-off-by: Eduardo Valentin <eduardo.valentin@nokia.com>
Acked-by: Jarkko Nikula <jhnikula@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Eduardo Valentin
2009-08-20 16:18:25 +03:00
committed by Mark Brown
parent ca6e2ce086
commit caebc0cb3b
3 changed files with 50 additions and 8 deletions
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7
sound/soc/omap/omap-pcm.c
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@@ -162,7 +162,7 @@ static int omap_pcm_prepare(struct snd_pcm_substream *substream)
*/
dma_params.data_type = OMAP_DMA_DATA_TYPE_S16;
dma_params.trigger = dma_data->dma_req;
dma_params.sync_mode = OMAP_DMA_SYNC_ELEMENT;
dma_params.sync_mode = dma_data->sync_mode;
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
dma_params.src_amode = OMAP_DMA_AMODE_POST_INC;
dma_params.dst_amode = OMAP_DMA_AMODE_CONSTANT;
@@ -205,6 +205,7 @@ static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_pcm_runtime *runtime = substream->runtime;
struct omap_runtime_data *prtd = runtime->private_data;
struct omap_pcm_dma_data *dma_data = prtd->dma_data;
unsigned long flags;
int ret = 0;
@@ -214,6 +215,10 @@ static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
prtd->period_index = 0;
/* Configure McBSP internal buffer usage */
if (dma_data->set_threshold)
dma_data->set_threshold(substream);
omap_start_dma(prtd->dma_ch);
break;