DPRAM driver on 440gp

Bob White bwhite at perigee.com
Fri May 7 01:35:31 EST 2004


I've got a basic read/write driver working (thanks to O'reilly ldd2) on
the dpram on the peripheral bus.

I remap the physical addresses using "io_base = ioremap64(...)" in the
driver open call and then the user read and write functions can access
the dpram just fine.

I'd like the user to be able to access the dpram using a pointer, but I
am having trouble figuring out the mmap examples.

Given that the physical address has already been mapped, via
ioremap64(), do I need remap_page_range()?  Does anyone have any ideas
on what the mmap file_op for this driver would look like?  Do I even
need mmap() or should I just use an ioctl to return the pointer I've
already got to the user?

Bob
--
Robert B. White        Perigee, A Division of Sensis Corp
Software Design Engr   316 Commerce Blvd.
TEL: 315.453.7842x29   Liverpool, NY  13088
FAX: 315.453.7917      www.Perigee.com


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