Sorry, I did not provide full picture. After this discussion on devel I've linked, I spoke to Michael what changes would be in compliance with EDK2 driver model guidelines. An agreement was reached: Root Bridge driver that implements SIO Protocol and Serial I/O driver (with new entrypoint) that depends on SIO by DEPEX. This way, driver would be a DXE Driver that runs new entrypoint only when SIO Protocol is present. I believe this approach doesn't violate UEFI Driver model rules since it uses standard DXE methods. Also, the approach of modifying driver's entrypoint was suggested by Zhichao Gao. -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#118822): https://edk2.groups.io/g/devel/message/118822 Mute This Topic: https://groups.io/mt/105959587/7686176 Group Owner: devel+owner@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io] -=-=-=-=-=-=-=-=-=-=-=-