[PATCH] IBM GPIO driver for PowerPC 4xx is back from the dead

[Eugene Surovegin]

On Fri, Sep 29, 2006 at 09:46:04AM +0200, Jean-Baptiste Maneyrol wrote:
> Here is a patch for linux 2.6.18 that makes come back the old ibm gpio
> driver from 2.6.10.
> 
> It is mainly useful for compatibility with old linux 2.4 from Montavista
> I think, because direct memory access seems the new way to go.

In my opinion it should stay dead. And no, direct memory access isn't 
a way to go - how are you gonna provide synchronization in this case? 
Think about different processes mucking with GPIO registers.

I think such low-level functionality should never be exported to the 
user-space in the first place. If your user-space needs such access 
make it explicit through procfs/sysfs (e.g. 
/proc/sys/dev/my_board/reset_that_device for GPIO pin wired to some 
chip reset) or just make a specific driver for your hardware.

-- 
Eugene