Lars-Peter Clausen wrote:

quoted

quoted

Maybe I've been out of the loop for too long, but why is that a particular
problem with this driver?

It is usually something you'd want to check in general to make sure that you
don't have multiple device that access the same iomem region at the same time.

I understand that, but I'm trying to figure out why of_iomap() is okay 
for hundreds of other drivers, but not this one.  I've used it dozens of 
times myself, without ever worrying about overlapping regions.