drm_atomic_get_old_private_obj_state
drm_atomic_get_old_private_obj_state(state, &mgr->base);
obj_state = drm_atomic_get_old_private_obj_state(state, &bridge->base);
EXPORT_SYMBOL(drm_atomic_get_old_private_obj_state);
drm_atomic_get_old_private_obj_state(const struct drm_atomic_state *state,