[PATCH AUTOSEL 5.4 10/11] ALSA: dmaengine_pcm: terminate dmaengine before synchronize

From: Sasha Levin
Date: Tue Jul 09 2024 - 12:57:49 EST


From: Shengjiu Wang <shengjiu.wang@xxxxxxx>

[ Upstream commit 6a7db25aad8ce6512b366d2ce1d0e60bac00a09d ]

When dmaengine supports pause function, in suspend state,
dmaengine_pause() is called instead of dmaengine_terminate_async(),

In end of playback stream, the runtime->state will go to
SNDRV_PCM_STATE_DRAINING, if system suspend & resume happen
at this time, application will not resume playback stream, the
stream will be closed directly, the dmaengine_terminate_async()
will not be called before the dmaengine_synchronize(), which
violates the call sequence for dmaengine_synchronize().

This behavior also happens for capture streams, but there is no
SNDRV_PCM_STATE_DRAINING state for capture. So use
dmaengine_tx_status() to check the DMA status if the status is
DMA_PAUSED, then call dmaengine_terminate_async() to terminate
dmaengine before dmaengine_synchronize().

Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
Link: https://patch.msgid.link/1718851218-27803-1-git-send-email-shengjiu.wang@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
sound/core/pcm_dmaengine.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/sound/core/pcm_dmaengine.c b/sound/core/pcm_dmaengine.c
index 5d9a24ca6f3ec..6c0d0a43baa11 100644
--- a/sound/core/pcm_dmaengine.c
+++ b/sound/core/pcm_dmaengine.c
@@ -345,6 +345,12 @@ EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
{
struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ struct dma_tx_state state;
+ enum dma_status status;
+
+ status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
+ if (status == DMA_PAUSED)
+ dmaengine_terminate_async(prtd->dma_chan);

dmaengine_synchronize(prtd->dma_chan);
kfree(prtd);
@@ -362,6 +368,12 @@ EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
{
struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ struct dma_tx_state state;
+ enum dma_status status;
+
+ status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
+ if (status == DMA_PAUSED)
+ dmaengine_terminate_async(prtd->dma_chan);

dmaengine_synchronize(prtd->dma_chan);
dma_release_channel(prtd->dma_chan);
--
2.43.0