Canon Patent Application: Multiple types of lenses supported in a single mount

This patent application deals with supporting a variety of lenses on a single unspecified mount.  These lenses may have different operating voltages, and also a different method of communication between the camera and the lens.

The interchangeable lens with which an imaging device is equipped is operating in response to supply of a power supply from the imaging device. However, the communicate modes which the interchangeable lens can respond [ the case where operating voltage changes with the types, or ] may differ. In order to be able to equip an imaging device with the interchangeable lens of several different types, the technology which distinguishes the type of interchangeable lens with which it was equipped is disclosed. 

This patent suggests that Canon is either looking to augment the EF mount or the EF-M mount some future expansion capability.

Japan Patent Application 2018-101080

Also, Japan Patent Application 2018-101079 discusses a similar intent;

The present invention relates to an image pickup apparatus, and more particularly to an image pickup apparatus including an interchangeable lens capable of communicating in a first communication mode, communication in a first communication mode and a second communication mode The present invention relates to an image pickup apparatus capable of selectively mounting a replaceable interchangeable lens.