Aha, good news. So this patch is already obsolete, for the Sierra stuffThe Sierra driver as it stands is very bare-bones; it doesn't yet have the larger buffers. So for now, I'll keep using the airprime one until sierra gets up to speed (though it seems like they should have a fair amount of common code).
anyway. And as I only have Sierra kit to work with, I reckon I should
drop out of this now.
I did make some changes to the last patch to do the cleanup stuff in the
open function, do you want to see those?