ASoC: SOF: fix uninitialised "work" with VirtIO

In the VirtIO case the sof_pcm_open() function isn't called on the
host during guest streaming, which then leaves "work" structures
uninitialised. However it is then used to handle position update
messages from the DSP. Move their initialisation to immediately after
allocation of the containing structure.
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20200325211233.27394-4-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/pcm.c

@@ -57,7 +57,7 @@ static int sof_pcm_dsp_params(struct snd_sof_pcm *spcm, struct snd_pcm_substream
 /*
  * sof pcm period elapse work
  */
-static void sof_pcm_period_elapsed_work(struct work_struct *work)
+void snd_sof_pcm_period_elapsed_work(struct work_struct *work)
 {
 	struct snd_sof_pcm_stream *sps =
 		container_of(work, struct snd_sof_pcm_stream,
@@ -475,8 +475,6 @@ static int sof_pcm_open(struct snd_soc_component *component,
 	dev_dbg(component->dev, "pcm: open stream %d dir %d\n",
 		spcm->pcm.pcm_id, substream->stream);
 
-	INIT_WORK(&spcm->stream[substream->stream].period_elapsed_work,
-		  sof_pcm_period_elapsed_work);
 
 	caps = &spcm->pcm.caps[substream->stream];
 

sound/soc/sof/sof-audio.h

@@ -11,6 +11,8 @@
 #ifndef __SOUND_SOC_SOF_AUDIO_H
 #define __SOUND_SOC_SOF_AUDIO_H
 
+#include <linux/workqueue.h>
+
 #include <sound/soc.h>
 #include <sound/control.h>
 #include <sound/sof/stream.h> /* needs to be included before control.h */
@@ -189,6 +191,7 @@ struct snd_sof_pcm *snd_sof_find_spcm_comp(struct snd_soc_component *scomp,
 struct snd_sof_pcm *snd_sof_find_spcm_pcm_id(struct snd_soc_component *scomp,
 					     unsigned int pcm_id);
 void snd_sof_pcm_period_elapsed(struct snd_pcm_substream *substream);
+void snd_sof_pcm_period_elapsed_work(struct work_struct *work);
 
 /*
  * Mixer IPC

sound/soc/sof/topology.c

@@ -9,6 +9,7 @@
 //
 
 #include <linux/firmware.h>
+#include <linux/workqueue.h>
 #include <sound/tlv.h>
 #include <sound/pcm_params.h>
 #include <uapi/sound/sof/tokens.h>
@@ -2461,8 +2462,11 @@ static int sof_dai_load(struct snd_soc_component *scomp, int index,
 
 	spcm->scomp = scomp;
 
-	for_each_pcm_streams(stream)
+	for_each_pcm_streams(stream) {
 		spcm->stream[stream].comp_id = COMP_ID_UNASSIGNED;
+		INIT_WORK(&spcm->stream[stream].period_elapsed_work,
+			  snd_sof_pcm_period_elapsed_work);
+	}
 
 	spcm->pcm = *pcm;
 	dev_dbg(scomp->dev, "tplg: load pcm %s\n", pcm->dai_name);