[PATCH 4.16 07/52] ALSA: aloop: Mark paused device as inactive

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Robert Rosengren <robert.rosengren@xxxxxxxx>

commit 306a4f3ca7f3c7dfa473ebd19d66e40e59d99734 upstream.

Show paused ALSA aloop device as inactive, i.e. the control
"PCM Slave Active" set as false. Notification sent upon state change.

This makes it possible for client capturing from aloop device to know if
data is expected. Without it the client expects data even if playback
is paused.

Signed-off-by: Robert Rosengren <robert.rosengren@xxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 sound/drivers/aloop.c |   12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

--- a/sound/drivers/aloop.c
+++ b/sound/drivers/aloop.c
@@ -296,6 +296,8 @@ static int loopback_trigger(struct snd_p
 		cable->pause |= stream;
 		loopback_timer_stop(dpcm);
 		spin_unlock(&cable->lock);
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			loopback_active_notify(dpcm);
 		break;
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 	case SNDRV_PCM_TRIGGER_RESUME:
@@ -304,6 +306,8 @@ static int loopback_trigger(struct snd_p
 		cable->pause &= ~stream;
 		loopback_timer_start(dpcm);
 		spin_unlock(&cable->lock);
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			loopback_active_notify(dpcm);
 		break;
 	default:
 		return -EINVAL;
@@ -892,9 +896,11 @@ static int loopback_active_get(struct sn
 			[kcontrol->id.subdevice][kcontrol->id.device ^ 1];
 	unsigned int val = 0;
 
-	if (cable != NULL)
-		val = (cable->running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ?
-									1 : 0;
+	if (cable != NULL) {
+		unsigned int running = cable->running ^ cable->pause;
+
+		val = (running & (1 << SNDRV_PCM_STREAM_PLAYBACK)) ? 1 : 0;
+	}
 	ucontrol->value.integer.value[0] = val;
 	return 0;
 }