I really rather hope that this guy doesn't start with changing the formatting to match BSD style first. That's just a stupid rat-race with no ending. This is what the guy who talked about BSD/KMS in XDC toulouse started out with, we haven't heard from him in 2 years.
The only thing that makes sense is the bare minimum infrastructural changes needed to run decently under some BSD kernels, and then regularly pulling in updates with minimal pain and overhead.
Oh, if only DRM drivers were not made a whole and complete part of the linux kernel monolith... Like we had it 5 years ago... Then the different codepaths for different linux and bsd kernel versions could happily live together. It really will not be that big of a API mess, and what will be there shouldn't be too hard to abstract cleanly.