V4L/DVB: s2255drv: removal of big kernel lock

big kernel lock removed from open function.
v4l2 code does not require locking the open function except
to check asynchronous firmware load state, which is protected
by a mutex

Signed-off-by: Dean Anderson <dean@sensoray.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/s2255drv.c

@@ -1753,7 +1753,6 @@ static int s2255_open(struct file *file)
 	int state;
 	dprintk(1, "s2255: open called (dev=%s)\n",
 		video_device_node_name(vdev));
-	lock_kernel();
 	for (i = 0; i < MAX_CHANNELS; i++)
 		if (&dev->vdev[i] == vdev) {
 			cur_channel = i;
@@ -1769,7 +1768,6 @@ static int s2255_open(struct file *file)
 	switch (state) {
 	case S2255_FW_DISCONNECTING:
 		mutex_unlock(&dev->open_lock);
-		unlock_kernel();
 		return -ENODEV;
 	case S2255_FW_FAILED:
 		s2255_dev_err(&dev->udev->dev,
@@ -1809,30 +1807,24 @@ static int s2255_open(struct file *file)
 		break;
 	case S2255_FW_FAILED:
 		printk(KERN_INFO "2255 firmware load failed.\n");
-		unlock_kernel();
 		return -ENODEV;
 	case S2255_FW_DISCONNECTING:
 		printk(KERN_INFO "%s: disconnecting\n", __func__);
-		unlock_kernel();
 		return -ENODEV;
 	case S2255_FW_LOADED_DSPWAIT:
 	case S2255_FW_NOTLOADED:
 		printk(KERN_INFO "%s: firmware not loaded yet"
 		       "please try again later\n",
 		       __func__);
-		unlock_kernel();
 		return -EAGAIN;
 	default:
 		printk(KERN_INFO "%s: unknown state\n", __func__);
-		unlock_kernel();
 		return -EFAULT;
 	}
 	/* allocate + initialize per filehandle data */
 	fh = kzalloc(sizeof(*fh), GFP_KERNEL);
-	if (NULL == fh) {
-		unlock_kernel();
+	if (NULL == fh)
 		return -ENOMEM;
-	}
 	file->private_data = fh;
 	fh->dev = dev;
 	fh->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
@@ -1860,7 +1852,6 @@ static int s2255_open(struct file *file)
 				    fh->type,
 				    V4L2_FIELD_INTERLACED,
 				    sizeof(struct s2255_buffer), fh);
-	unlock_kernel();
 	return 0;
 }