Hi Laurent,
From a quick look only cadence/cdns-mhdp8546 subclass
drm_bridge_state and I wonder if the right thing to do would be to implement fallback to the helpers if the bridge driver do not set any of the .atomic_duplicate_state(), .atomic_destroy_state(), or .atomic_reset().
That would drop the following from a few bridges: .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, .atomic_reset = drm_atomic_helper_bridge_reset,
To answer myself here. This would create a dependency from the core to the helpers which is not OK so idea dropped again.
Sam