RTEMS GPIO API

[André Marques]

Hello,

I have just updated my GSOC blog [1] with a detailed post about how a 
rtems-wide GPIO API could look like, and at the same time exposing the 
current features of the Raspberry Pi GPIO API and how it can evolve to 
that level.

I tried to make it as generic and flexible as possible, but that can be 
hard with the number of platforms where rtems can be used. Api and 
method naming were somewhat overlooked, as well as the definition of 
possible error codes since I am not sure if it would be correct to have 
a set of error codes for this API, or if it should use 
rtems_status_code, or other.

Current code for the Raspberry Pi GPIO API can be looked at in [2], 
where I am currently carving out the rpi specific code.

I tried to be as clear as possible in the blog, and now I would like to 
ask any interested party to have a look and hopefully point failure 
points and suggestions, or ask for clarifications. It would also be 
interesting to hear the community expectations towards an API such as 
this one.

[1] - https://asuolgsoc2014.wordpress.com/2015/06/08/rtems-gpio-api/
[2] - 
https://github.com/asuol/rtems/tree/GPIO_API/c/src/lib/libbsp/arm/raspberrypi/gpio

Thanks for your time,
André Marques