/** * radeon_fence_driver_start_ring - make the fence driver * ready for use on the requested ring. * * @rdev: radeon device pointer * @ring: ring index to start the fence driver on * * Make the fence driver ready for processing (all asics). * Not all asics have all rings, so each asic will only * start the fence driver on the rings it has. * Returns 0 for success, errors for failure. */