if (err)
                return err;
 
-       mutex_lock(&dev->lock);
        fh->win = f->fmt.win;
 
        spin_lock_irqsave(&dev->slock, flags);
        viu_start_preview(dev, fh);
        spin_unlock_irqrestore(&dev->slock, flags);
-       mutex_unlock(&dev->lock);
        return 0;
 }
 
        videobuf_queue_dma_contig_init(&fh->vb_vidq, &viu_video_qops,
                                       dev->dev, &fh->vbq_lock,
                                       fh->type, V4L2_FIELD_INTERLACED,
-                                      sizeof(struct viu_buf), fh, NULL);
+                                      sizeof(struct viu_buf), fh,
+                                      &fh->dev->lock);
        return 0;
 }
 
        .release        = viu_release,
        .read           = viu_read,
        .poll           = viu_poll,
-       .ioctl          = video_ioctl2, /* V4L2 ioctl handler */
+       .unlocked_ioctl = video_ioctl2, /* V4L2 ioctl handler */
        .mmap           = viu_mmap,
 };
 
        INIT_LIST_HEAD(&viu_dev->vidq.active);
        INIT_LIST_HEAD(&viu_dev->vidq.queued);
 
-       /* initialize locks */
-       mutex_init(&viu_dev->lock);
-
        snprintf(viu_dev->v4l2_dev.name,
                 sizeof(viu_dev->v4l2_dev.name), "%s", "VIU");
        ret = v4l2_device_register(viu_dev->dev, &viu_dev->v4l2_dev);
 
        viu_dev->vdev = vdev;
 
+       /* initialize locks */
+       mutex_init(&viu_dev->lock);
+       viu_dev->vdev->lock = &viu_dev->lock;
+       spin_lock_init(&viu_dev->slock);
+
        video_set_drvdata(viu_dev->vdev, viu_dev);
 
+       mutex_lock(&viu_dev->lock);
+
        ret = video_register_device(viu_dev->vdev, VFL_TYPE_GRABBER, -1);
        if (ret < 0) {
                video_device_release(viu_dev->vdev);
                goto err_irq;
        }
 
+       mutex_unlock(&viu_dev->lock);
+
        dev_info(&op->dev, "Freescale VIU Video Capture Board\n");
        return ret;
 
 err_clk:
        video_unregister_device(viu_dev->vdev);
 err_vdev:
+       mutex_unlock(&viu_dev->lock);
        i2c_put_adapter(ad);
        v4l2_device_unregister(&viu_dev->v4l2_dev);
 err: