ASoC: SOF: add elapse work for spcm to fix trigger stop ipc timeout

We do elapse in interrupt context at the moment, this will lead to ipc
timeout at trigger stop with some possibility, where the pcm elapse will
call trigger stop and the stop ipc will timeout as the ipc interrupt is
disabled at this context.
Here we introduce a work to do pcm period elapse, and the stress test
shows that it fixes this kind of ipc timeout issue.
Signed-off-by: Keyon Jie <yang.jie@linux.intel.com>

Author: keyonjie

sound/soc/sof/pcm.c

@@ -52,6 +52,39 @@ static int sof_pcm_dsp_params(struct snd_sof_pcm *spcm, struct snd_pcm_substream
 returnret;
 }
 
+/*
+ * sof pcm period elapse work
+ */
+staticvoidsof_elapsed_work(structwork_struct*work)
+{
+structsnd_sof_pcm_stream*sps=
+container_of(work, structsnd_sof_pcm_stream, elapse_work);
+
+snd_pcm_period_elapsed(sps->substream);
+}
+
+/*
+ * sof pcm period elapse, this might be called at irq context.
+ */
+voidsnd_sof_pcm_elapsed(structsnd_pcm_substream*substream)
+{
+structsnd_soc_pcm_runtime*rtd=substream->private_data;
+structsnd_soc_component*component=
+snd_soc_rtdcom_lookup(rtd, DRV_NAME);
+structsnd_sof_dev*sdev=snd_soc_component_get_drvdata(component);
+structsnd_sof_pcm*spcm;
+
+spcm=snd_sof_find_spcm_dai(sdev, rtd);
+if (!spcm) {
+dev_err(sdev->dev,
+"error: period elapsed for unknown stream!\n");
+return;
+	}
+
+schedule_work(&spcm->stream[substream->stream].elapse_work);
+}
+EXPORT_SYMBOL(snd_sof_pcm_elapsed);
+
 /* this may get called several times by oss emulation */
 staticintsof_pcm_hw_params(structsnd_pcm_substream*substream,
 structsnd_pcm_hw_params*params)
@@ -169,6 +202,9 @@ static int sof_pcm_hw_params(struct snd_pcm_substream *substream,
 /* save pcm hw_params */
 memcpy(&spcm->params[substream->stream], params, sizeof(*params));
 
+INIT_WORK(&spcm->stream[substream->stream].elapse_work,
+sof_elapsed_work);
+
 returnret;
 }
 
@@ -203,6 +239,9 @@ static int sof_pcm_hw_free(struct snd_pcm_substream *substream)
 sizeof(stream), &reply, sizeof(reply));
 
 snd_pcm_lib_free_pages(substream);
+
+cancel_work_sync(&spcm->stream[substream->stream].elapse_work);
+
 returnret;
 }
 

sound/soc/sof/sof-priv.h

@@ -274,6 +274,7 @@ struct snd_sof_pcm_stream {
 structsnd_dma_bufferpage_table;
 structsof_ipc_stream_posnposn;
 structsnd_pcm_substream*substream;
+structwork_structelapse_work;
 };
 
 /* ALSA SOF PCM device */
@@ -495,6 +496,7 @@ struct snd_sof_pcm *snd_sof_find_spcm_comp(struct snd_sof_dev *sdev,
 int*direction);
 structsnd_sof_pcm*snd_sof_find_spcm_pcm_id(structsnd_sof_dev*sdev,
 unsigned intpcm_id);
+voidsnd_sof_pcm_elapsed(structsnd_pcm_substream*substream);
 
 /*
  * Stream IPC