Re: [Gumstix-users] Efficient GPIO from C

[Craig H. <cr...@gu...>]

On Dec 2, 2005, at 4:31 PM, Dave Hylands wrote:

> So, I'd propse that we extend the proc_gpio.c to add a proper driver
> and provide atomic access as appropriate. It could then also implement
> mmap to expose the appropriate registers for the GPIO twiddling.

It's actually something which needs to happen at a deeper level --  
i've done some thinking on this in the past.  You eseentially want  
something akin to the existing resource allocation system, where you  
can grab an IRQ, memory chunk, etc.  Otherwise, proc_gpio might be  
whacking a GPIO which is already in use by some driver that needs it  
configured with some specific alt fn.

C