diff options
author | Michal Bachraty <michal.bachraty@streamunlimited.com> | 2013-02-28 16:07:08 +0100 |
---|---|---|
committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2013-03-04 11:09:13 +0800 |
commit | 2952b27e2e463b28d5c0f04000f96b968137ca42 (patch) | |
tree | 4bbc01aefee1411cb3334e56d9d4bd82bc19af93 /sound/soc/davinci/davinci-pcm.c | |
parent | 6dbe51c251a327e012439c4772097a13df43c5b8 (diff) |
ASoC: davinci-mcasp: Add support for multichannel playback
Davinci McASP has support for I2S multichannel playback.
For I2S playback/receive, each serializer is capable to play 2 channels
(L/R) audio data.Serializer function (Playback-receive-none) is configured
in DT, depending on hardware specification. It is possible to play less
channels than configured in DT. For that purpose,only specific number of
active serializers are enabled. McASP FIFO need to have DMA transfer Bcnt
set to number of enabled serializers, otherwise no data are transfered to
McASP and Alsa generates "DMA/IRQ playback write error (DMA or IRQ trouble?)"
error. For TDM mode, McASP is capable to play or receive 32 channels for one
serializer. McAsp has support for max 16 serializer, therefore max channels
is 32 * 8.
Signed-off-by: Michal Bachraty <michal.bachraty@streamunlimited.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Diffstat (limited to 'sound/soc/davinci/davinci-pcm.c')
-rw-r--r-- | sound/soc/davinci/davinci-pcm.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/sound/soc/davinci/davinci-pcm.c b/sound/soc/davinci/davinci-pcm.c index afab81f844ae..078031d61167 100644 --- a/sound/soc/davinci/davinci-pcm.c +++ b/sound/soc/davinci/davinci-pcm.c @@ -181,6 +181,7 @@ static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream) unsigned short acnt; unsigned int count; unsigned int fifo_level; + unsigned char serializers = prtd->params->active_serializers; period_size = snd_pcm_lib_period_bytes(substream); dma_offset = prtd->period * period_size; @@ -194,14 +195,14 @@ static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream) data_type = prtd->params->data_type; count = period_size / data_type; if (fifo_level) - count /= fifo_level; + count /= fifo_level * serializers; if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { src = dma_pos; dst = prtd->params->dma_addr; src_bidx = data_type; - dst_bidx = 0; - src_cidx = data_type * fifo_level; + dst_bidx = 4; + src_cidx = data_type * fifo_level * serializers; dst_cidx = 0; } else { src = prtd->params->dma_addr; @@ -209,7 +210,7 @@ static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream) src_bidx = 0; dst_bidx = data_type; src_cidx = 0; - dst_cidx = data_type * fifo_level; + dst_cidx = data_type * fifo_level * serializers; } acnt = prtd->params->acnt; @@ -223,9 +224,10 @@ static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream) edma_set_transfer_params(prtd->asp_link[0], acnt, count, 1, 0, ASYNC); else - edma_set_transfer_params(prtd->asp_link[0], acnt, fifo_level, - count, fifo_level, - ABSYNC); + edma_set_transfer_params(prtd->asp_link[0], acnt, + fifo_level * serializers, + count, fifo_level * serializers, + ABSYNC); } static void davinci_pcm_dma_irq(unsigned link, u16 ch_status, void *data) |