+static int w9966_exclusive_open(struct inode *inode, struct file *file)
+{
+ struct w9966_dev *cam = video_drvdata(file);
+
+ return test_and_set_bit(0, &cam->in_use) ? -EBUSY : 0;
+}
+
+static int w9966_exclusive_release(struct inode *inode, struct file *file)
+{
+ struct w9966_dev *cam = video_drvdata(file);
+
+ clear_bit(0, &cam->in_use);
+ return 0;
+}
+