V4L/DVB (5842): ivtv: Add locking to ensure stream setup is atomic.

Starting an MPEG and VBI capture simultaneously caused errors in
the VBI setup: this setup was done twice when it should be done
only for the first stream that is opened.
Added a mutex to prevent this from happening.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/media/video/ivtv/ivtv-driver.c b/drivers/media/video/ivtv/ivtv-driver.c
index 28a53c42020d..ab7c3f6d3531 100644
--- a/drivers/media/video/ivtv/ivtv-driver.c
+++ b/drivers/media/video/ivtv/ivtv-driver.c
@@ -623,6 +623,7 @@ static int __devinit ivtv_init_struct1(struct ivtv *itv)
         itv->enc_mbox.max_mbox = 2; /* the encoder has 3 mailboxes (0-2) */
         itv->dec_mbox.max_mbox = 1; /* the decoder has 2 mailboxes (0-1) */
 
+        mutex_init(&itv->serialize_lock);
         mutex_init(&itv->i2c_bus_lock);
         mutex_init(&itv->udma.lock);