drm_crtc_vblank_waitqueue
EXPORT_SYMBOL(drm_crtc_vblank_waitqueue);
add_wait_queue(drm_crtc_vblank_waitqueue(crtc), &wait->wait);
wait_queue_head_t *wq = drm_crtc_vblank_waitqueue(&crtc->base);
wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc);