On Fri, Dec 18, 2020 at 01:17:09PM +0000, Mark Brown wrote: > As previously discussed this will need the auxilliary bus extending to > support at least interrupts and possibly also general resources. I thought the recent LWN article summed it up nicely, auxillary bus is for gluing to subsystems together using a driver specific software API to connect to the HW, MFD is for splitting a physical HW into disjoint regions of HW. Maybe there is some overlap, but if you want to add HW representations to the general auxillary device then I think you are using it for the wrong thing. Jason