[PATCH v3 03/15] dmaengine: Add flags parameter to dmaengine_prep_dma_cyclic()

From: Peter Ujfalusi
Date: Fri Sep 14 2012 - 08:05:48 EST

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@xxxxxx>
CC: Lars-Peter Clausen <lars@xxxxxxxxxx>
include/linux/dmaengine.h | 3 ++-
sound/soc/soc-dmaengine-pcm.c | 6 +++++-
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 9c02a45..2abcac5 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -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, NULL);
diff --git a/sound/soc/soc-dmaengine-pcm.c b/sound/soc/soc-dmaengine-pcm.c
index 5df529e..bbc1257 100644
--- a/sound/soc/soc-dmaengine-pcm.c
+++ b/sound/soc/soc-dmaengine-pcm.c
@@ -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)
prtd->pos = 0;
desc = dmaengine_prep_dma_cyclic(chan,
- snd_pcm_lib_period_bytes(substream), direction);
+ snd_pcm_lib_period_bytes(substream), direction, flags);

if (!desc)
return -ENOMEM;

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