ASoC: soc-compress: Initialise delayed work to power down audio

Delayed work was scheduled but not initialised, this patch adds the
actual work and initialises it.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Tested-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/soc-compress.c

@@ -75,6 +75,34 @@ static int soc_compr_open(struct snd_compr_stream *cstream)
 	return ret;
 }
 
+/*
+ * Power down the audio subsystem pmdown_time msecs after close is called.
+ * This is to ensure there are no pops or clicks in between any music tracks
+ * due to DAPM power cycling.
+ */
+static void close_delayed_work(struct work_struct *work)
+{
+	struct snd_soc_pcm_runtime *rtd =
+			container_of(work, struct snd_soc_pcm_runtime, delayed_work.work);
+	struct snd_soc_dai *codec_dai = rtd->codec_dai;
+
+	mutex_lock_nested(&rtd->pcm_mutex, rtd->pcm_subclass);
+
+	dev_dbg(rtd->dev, "ASoC: pop wq checking: %s status: %s waiting: %s\n",
+		 codec_dai->driver->playback.stream_name,
+		 codec_dai->playback_active ? "active" : "inactive",
+		 rtd->pop_wait ? "yes" : "no");
+
+	/* are we waiting on this codec DAI stream */
+	if (rtd->pop_wait == 1) {
+		rtd->pop_wait = 0;
+		snd_soc_dapm_stream_event(rtd, SNDRV_PCM_STREAM_PLAYBACK,
+					  SND_SOC_DAPM_STREAM_STOP);
+	}
+
+	mutex_unlock(&rtd->pcm_mutex);
+}
+
 static int soc_compr_free(struct snd_compr_stream *cstream)
 {
 	struct snd_soc_pcm_runtime *rtd = cstream->private_data;
@@ -317,6 +345,9 @@ int soc_new_compress(struct snd_soc_pcm_runtime *rtd, int num)
 		return ret;
 	}
 
+	/* DAPM dai link stream work */
+	INIT_DELAYED_WORK(&rtd->delayed_work, close_delayed_work);
+
 	rtd->compr = compr;
 	compr->private_data = rtd;