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dmaengine: Add flags parameter to dmaengine_prep_dma_cyclic() 

With this parameter added to dmaengine_prep_dma_cyclic() the API will be in
sync with other dmaengine_prep_*() functions.
The dmaengine_prep_dma_cyclic() function primarily used by audio for cyclic
transfer required by ALSA, we use the from audio to ask dma drivers to
suppress interrupts (if DMA_PREP_INTERRUPT is cleared) when it is supported
on the platform.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
CC: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Peter Ujfalusi 2012-09-24 10:58:04 +03:00 committed by Takashi Iwai
parent 9d069dc00b
commit e7736cdea2
2 changed files with 7 additions and 2 deletions
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3
include/linux/dmaengine.h
View File

@ -653,7 +653,8 @@ static inline struct dma_async_tx_descriptor *dmaengine_prep_rio_sg(
static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction dir)
size_t period_len, enum dma_transfer_direction dir,
unsigned long flags)
{
return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
period_len, dir, flags, NULL);

6
sound/soc/soc-dmaengine-pcm.c
View File

@ -140,14 +140,18 @@ static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
struct dma_chan *chan = prtd->dma_chan;
struct dma_async_tx_descriptor *desc;
enum dma_transfer_direction direction;
unsigned long flags = DMA_CTRL_ACK;
direction = snd_pcm_substream_to_dma_direction(substream);
if (!substream->runtime->no_period_wakeup)
flags |= DMA_PREP_INTERRUPT;
prtd->pos = 0;
desc = dmaengine_prep_dma_cyclic(chan,
substream->runtime->dma_addr,
snd_pcm_lib_buffer_bytes(substream),
snd_pcm_lib_period_bytes(substream), direction);
snd_pcm_lib_period_bytes(substream), direction, flags);
if (!desc)
return -ENOMEM;