VIDIOC_S_PRIORITY
__set_bit(_IOC_NR(VIDIOC_S_PRIORITY), valid_ioctls);
set_bit(_IOC_NR(VIDIOC_S_PRIORITY), vdev->valid_ioctls);
IOCTL_INFO(VIDIOC_S_PRIORITY, v4l_s_priority, v4l_print_u32, INFO_FL_PRIO),
ret = ioctl(fd, VIDIOC_S_PRIORITY, &new_priority);
ret = ioctl(fd, VIDIOC_S_PRIORITY, &old_priority);