[PATCH 1/2] em28xx-audio: fix user counting in snd_em28xx_capture_open()

[PATCH 1/2] em28xx-audio: fix user counting in snd_em28xx_capture_open()

[Frank Schäfer]

dev->adev.users always needs to be increased when snd_em28xx_capture_open() is
called and succeeds.

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
---
 drivers/media/usb/em28xx/em28xx-audio.c |   22 +++++++++++-----------
 1 Datei geändert, 11 Zeilen hinzugefügt(+), 11 Zeilen entfernt(-)

diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c
index 05e9bd1..dfdfa77 100644
--- a/drivers/media/usb/em28xx/em28xx-audio.c
+++ b/drivers/media/usb/em28xx/em28xx-audio.c
@@ -252,7 +252,7 @@ static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
 {
 	struct em28xx *dev = snd_pcm_substream_chip(substream);
 	struct snd_pcm_runtime *runtime = substream->runtime;
-	int ret = 0;
+	int nonblock, ret = 0;
 
 	if (!dev) {
 		em28xx_err("BUG: em28xx can't find device struct."
@@ -265,15 +265,15 @@ static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
 
 	dprintk("opening device and trying to acquire exclusive lock\n");
 
+	nonblock = !!(substream->f_flags & O_NONBLOCK);
+	if (nonblock) {
+		if (!mutex_trylock(&dev->lock))
+		return -EAGAIN;
+	} else
+		mutex_lock(&dev->lock);
+
 	runtime->hw = snd_em28xx_hw_capture;
 	if ((dev->alt == 0 || dev->is_audio_only) && dev->adev.users == 0) {
-		int nonblock = !!(substream->f_flags & O_NONBLOCK);
-
-		if (nonblock) {
-			if (!mutex_trylock(&dev->lock))
-				return -EAGAIN;
-		} else
-			mutex_lock(&dev->lock);
 		if (dev->is_audio_only)
 			/* vendor audio is on a separate interface */
 			dev->alt = 1;
@@ -299,11 +299,11 @@ static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
 		ret = em28xx_audio_analog_set(dev);
 		if (ret < 0)
 			goto err;
-
-		dev->adev.users++;
-		mutex_unlock(&dev->lock);
 	}
 
+	dev->adev.users++;
+	mutex_unlock(&dev->lock);
+
 	/* Dynamically adjust the period size */
 	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 	snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
-- 
1.7.10.4

[PATCH 2/2] em28xx-audio: make sure audio is unmuted on open()

[Frank Schäfer]

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
---
 drivers/media/usb/em28xx/em28xx-audio.c |   42 ++++++++++++++++---------------
 1 Datei geändert, 22 Zeilen hinzugefügt(+), 20 Zeilen entfernt(-)

diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c
index dfdfa77..a3daf07 100644
--- a/drivers/media/usb/em28xx/em28xx-audio.c
+++ b/drivers/media/usb/em28xx/em28xx-audio.c
@@ -273,26 +273,28 @@ static int snd_em28xx_capture_open(struct snd_pcm_substream *substream)
 		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;
-- 
1.7.10.4