[PATCH 4/5] use mutex instead of semaphore in Virtual Video driver

Matthias Kaehlcke
2007-07-01T16:32:48Z

The Virtual Video driver uses a semaphore as mutex. Use the mutex API
instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>

--

diff --git a/drivers/media/video/vivi.c b/drivers/media/video/vivi.c
index f7e1d19..e86f4cd 100644
--- a/drivers/media/video/vivi.c
+++ b/drivers/media/video/vivi.c
@@ -25,6 +25,7 @@
#include <linux/pci.h>
#include <linux/random.h>
#include <linux/version.h>
+#include <linux/mutex.h>
#include <linux/videodev2.h>
#include <linux/dma-mapping.h>
#ifdef CONFIG_VIDEO_V4L1_COMPAT
@@ -168,7 +169,7 @@ static LIST_HEAD(vivi_devlist);
struct vivi_dev {
struct list_head vivi_devlist;

- struct semaphore lock;
+ struct mutex lock;

int users;

@@ -892,16 +893,16 @@ static struct videobuf_queue_ops vivi_video_qops = {
static int res_get(struct vivi_dev *dev, struct vivi_fh *fh)
{
/* is it free? */
- down(&dev->lock);
+ mutex_lock(&dev->lock);
if (dev->resources) {
/* no, someone else uses it */
- up(&dev->lock);
+ mutex_unlock(&dev->lock);
return 0;
}
/* it's free, grab it */
dev->resources =1;
dprintk(1,"res: get\n");
- up(&dev->lock);
+ mutex_unlock(&dev->lock);
return 1;
}

@@ -912,10 +913,10 @@ static int res_locked(struct vivi_dev *dev)

static void res_free(struct vivi_dev *dev, struct vivi_fh *fh)
{
- down(&dev->lock);
+ mutex_lock(&dev->lock);
dev->resources = 0;
dprintk(1,"res: put\n");
- up(&dev->lock);
+ mutex_lock(&dev->lock);
}

/* ------------------------------------------------------------------
@@ -1422,7 +1423,7 @@ static int __init vivi_init(void)
init_waitqueue_head(&dev->vidq.wq);

/* initialize locks */
- init_MUTEX(&dev->lock);
+ mutex_init(&dev->lock);

dev->vidq.timeout.function = vivi_vid_timeout;
dev->vidq.timeout.data = (unsigned long)dev;

--
Matthias Kaehlcke
Linux Application Developer
Barcelona

In itself, homosexuality is as limiting as heterosexuality: the
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a human being, without feeling fear, restraint, or obligation
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