[media] em28xx-audio: make sure audio is unmuted on open()

In all cases, when the first capture is called, we need to
call the code that unmutes the volume.

Signed-off-by: Frank Schäfer <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/usb/em28xx/em28xx-audio.c

···
 		mutex_lock(&dev->lock);
 
 	runtime->hw = snd_em28xx_hw_capture;
-	if ((dev->alt == 0 || dev->is_audio_only) && dev->adev.users == 0) {
-		if (dev->is_audio_only)
-			/* vendor audio is on a separate interface */
-			dev->alt = 1;
-		else
-			/* vendor audio is on the same interface as video */
-			dev->alt = 7;
-			/*
-			 * FIXME: The intention seems to be to select the alt
-			 * setting with the largest wMaxPacketSize for the video
-			 * endpoint.
-			 * At least dev->alt should be used instead, but we
-			 * should probably not touch it at all if it is
-			 * already >0, because wMaxPacketSize of the audio
-			 * endpoints seems to be the same for all.
-			 */
 
-		dprintk("changing alternate number on interface %d to %d\n",
-			dev->ifnum, dev->alt);
-		usb_set_interface(dev->udev, dev->ifnum, dev->alt);
+	if (dev->adev.users == 0) {
+		if (dev->alt == 0 || dev->is_audio_only) {
+			if (dev->is_audio_only)
+				/* audio is on a separate interface */
+				dev->alt = 1;
+			else
+				/* audio is on the same interface as video */
+				dev->alt = 7;
+				/*
+				 * FIXME: The intention seems to be to select
+				 * the alt setting with the largest
+				 * wMaxPacketSize for the video endpoint.
+				 * At least dev->alt should be used instead, but
+				 * we should probably not touch it at all if it
+				 * is already >0, because wMaxPacketSize of the
+				 * audio endpoints seems to be the same for all.
+				 */
+			dprintk("changing alternate number on interface %d to %d\n",
+				dev->ifnum, dev->alt);
+			usb_set_interface(dev->udev, dev->ifnum, dev->alt);
+		}
 
 		/* Sets volume, mute, etc */
 		dev->mute = 0;