static void init_vdev(struct video_device *vdev, int nr)
{
	MARK();
	vidioc_fill_name(vdev->name, sizeof(vdev->name), nr);

#ifdef V4L2LOOPBACK_WITH_STD
	vdev->tvnorms      = V4L2_STD_ALL;
#endif /* V4L2LOOPBACK_WITH_STD */

	vdev->vfl_type     = VFL_TYPE_VIDEO;
	vdev->fops         = &v4l2_loopback_fops;
	vdev->ioctl_ops    = &v4l2_loopback_ioctl_ops;
	vdev->release      = &video_device_release;
	vdev->minor        = -1;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
	vdev->device_caps  =
		V4L2_CAP_DEVICE_CAPS |
#ifdef V4L2_CAP_VIDEO_M2M
		V4L2_CAP_VIDEO_M2M |
#endif
                V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
                V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
#endif
	if (debug > 1)
		#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 20, 0)
			vdev->debug = V4L2_DEBUG_IOCTL | V4L2_DEBUG_IOCTL_ARG;
		#else
			vdev->dev_debug = V4L2_DEV_DEBUG_IOCTL | V4L2_DEV_DEBUG_IOCTL_ARG;
		#endif

	/* since kernel-3.7, there is a new field 'vfl_dir' that has to be
	 * set to VFL_DIR_M2M for bidrectional devices */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 7, 0)
	vdev->vfl_dir = VFL_DIR_M2M;
#endif

	MARK();
}
static void init_vdev(struct video_device *vdev, int nr)
{
	MARK();
	vidioc_fill_name(vdev->name, sizeof(vdev->name), nr);

#ifdef V4L2LOOPBACK_WITH_STD
	vdev->tvnorms      = V4L2_STD_ALL;
#endif  

	vdev->vfl_type     = VFL_TYPE_VIDEO;
	vdev->fops         = &v4l2_loopback_fops;
	vdev->ioctl_ops    = &v4l2_loopback_ioctl_ops;
	vdev->release      = &video_device_release;
	vdev->minor        = -1;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 7, 0)
	vdev->device_caps  =
		V4L2_CAP_DEVICE_CAPS |
#ifdef V4L2_CAP_VIDEO_M2M
		V4L2_CAP_VIDEO_M2M |
#endif
                V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT |
                V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
#endif
	if (debug > 1)
		#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 20, 0)
			vdev->debug = V4L2_DEBUG_IOCTL | V4L2_DEBUG_IOCTL_ARG;
		#else
			vdev->dev_debug = V4L2_DEV_DEBUG_IOCTL | V4L2_DEV_DEBUG_IOCTL_ARG;
		#endif

	 
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 7, 0)
	vdev->vfl_dir = VFL_DIR_M2M;
#endif

	MARK();
}