[PATCH 4.1 039/123] ALSA: line6: Fix -EBUSY error during active monitoring

From: Greg Kroah-Hartman
Date: Sat Aug 08 2015 - 18:17:11 EST


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

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

From: Takashi Iwai <tiwai@xxxxxxx>

commit 4d0e677523a999e1dec28e55cc314c47ba09ca12 upstream.

When a monitor stream is active, the next PCM stream access results in
EBUSY error because of the check in line6_stream_start(). Fix this by
just skipping the submission of pending URBs when the stream is
already running instead.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=101431
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/usb/line6/pcm.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

--- a/sound/usb/line6/pcm.c
+++ b/sound/usb/line6/pcm.c
@@ -186,12 +186,8 @@ static int line6_stream_start(struct snd
int ret = 0;

spin_lock_irqsave(&pstr->lock, flags);
- if (!test_and_set_bit(type, &pstr->running)) {
- if (pstr->active_urbs || pstr->unlink_urbs) {
- ret = -EBUSY;
- goto error;
- }
-
+ if (!test_and_set_bit(type, &pstr->running) &&
+ !(pstr->active_urbs || pstr->unlink_urbs)) {
pstr->count = 0;
/* Submit all currently available URBs */
if (direction == SNDRV_PCM_STREAM_PLAYBACK)
@@ -199,7 +195,6 @@ static int line6_stream_start(struct snd
else
ret = line6_submit_audio_in_all_urbs(line6pcm);
}
- error:
if (ret < 0)
clear_bit(type, &pstr->running);
spin_unlock_irqrestore(&pstr->lock, flags);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/