[PATCH 1/2] dmaengine: Add flags parameter to dmaengine_prep_dma_cyclic()
From: Peter Ujfalusi <hidden>
Date: 2012-09-24 07:57:17
Also in:
alsa-devel, lkml
Subsystem:
dma generic offload engine subsystem, sound, sound - soc layer / dynamic audio power management (asoc), the rest · Maintainers:
Vinod Koul, Jaroslav Kysela, Takashi Iwai, Liam Girdwood, Mark Brown, Linus Torvalds
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 <redacted> CC: Lars-Peter Clausen <lars@metafoo.de> --- 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 09da4e5..d3201e4 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, flags, 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) + 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;
--
1.7.12