redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

ASoC: omap-mcbsp: Use sDMA packet mode instead of frame mode

Browse source 
When McBSP is configured in threshold mode we can use sDMA packet mode in
all cases.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Peter Ujfalusi 2012-09-14 15:05:49 +03:00 committed by Mark Brown
parent 2dde5b909e
commit dffb360e64
1 changed files with 16 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

45
sound/soc/omap/omap-mcbsp.c
View file

@ -81,9 +81,6 @@ static void omap_mcbsp_set_threshold(struct snd_pcm_substream *substream)
*/
if (dma_data->packet_size)
words = dma_data->packet_size;
else if (mcbsp->dma_op_mode == MCBSP_DMA_MODE_THRESHOLD)
words = snd_pcm_lib_period_bytes(substream) /
(mcbsp->wlen / 8);
else
words = 1;
@ -251,6 +248,7 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
dma_data->set_threshold = omap_mcbsp_set_threshold;
if (mcbsp->dma_op_mode == MCBSP_DMA_MODE_THRESHOLD) {
int period_words, max_thrsh;
int divider = 0;
period_words = params_period_bytes(params) / (wlen / 8);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
@ -258,34 +256,23 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
else
max_thrsh = mcbsp->max_rx_thres;
/*
* If the period contains less or equal number of words,
* we are using the original threshold mode setup:
* McBSP threshold = sDMA frame size = period_size
* Otherwise we switch to sDMA packet mode:
* McBSP threshold = sDMA packet size
* sDMA frame size = period size
* Use sDMA packet mode if McBSP is in threshold mode:
* If period words less than the FIFO size the packet
* size is set to the number of period words, otherwise
* Look for the biggest threshold value which divides
* the period size evenly.
*/
if (period_words > max_thrsh) {
int divider = 0;
divider = period_words / max_thrsh;
if (period_words % max_thrsh)
divider++;
while (period_words % divider &&
divider < period_words)
divider++;
if (divider == period_words)
return -EINVAL;
/*
* Look for the biggest threshold value, which
* divides the period size evenly.
*/
divider = period_words / max_thrsh;
if (period_words % max_thrsh)
divider++;
while (period_words % divider &&
divider < period_words)
divider++;
if (divider == period_words)
return -EINVAL;
pkt_size = period_words / divider;
sync_mode = OMAP_DMA_SYNC_PACKET;
} else {
sync_mode = OMAP_DMA_SYNC_FRAME;
}
pkt_size = period_words / divider;
sync_mode = OMAP_DMA_SYNC_PACKET;
} else if (channels > 1) {
/* Use packet mode for non mono streams */
pkt_size = channels;