diff options
Diffstat (limited to 'drivers/media/video/c-qcam.c')
| -rw-r--r-- | drivers/media/video/c-qcam.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/drivers/media/video/c-qcam.c b/drivers/media/video/c-qcam.c index 7f6c6b4bec1..2196c1dc5ae 100644 --- a/drivers/media/video/c-qcam.c +++ b/drivers/media/video/c-qcam.c @@ -51,6 +51,7 @@ struct qcam_device { int contrast, brightness, whitebal; int top, left; unsigned int bidirectional; + unsigned long in_use; struct mutex lock; }; @@ -687,11 +688,28 @@ static ssize_t qcam_read(struct file *file, char __user *buf, return len; } +static int qcam_exclusive_open(struct inode *inode, struct file *file) +{ + struct video_device *dev = video_devdata(file); + struct qcam_device *qcam = (struct qcam_device *)dev; + + return test_and_set_bit(0, &qcam->in_use) ? -EBUSY : 0; +} + +static int qcam_exclusive_release(struct inode *inode, struct file *file) +{ + struct video_device *dev = video_devdata(file); + struct qcam_device *qcam = (struct qcam_device *)dev; + + clear_bit(0, &qcam->in_use); + return 0; +} + /* video device template */ static const struct file_operations qcam_fops = { .owner = THIS_MODULE, - .open = video_exclusive_open, - .release = video_exclusive_release, + .open = qcam_exclusive_open, + .release = qcam_exclusive_release, .ioctl = qcam_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = v4l_compat_ioctl32, |