I have installed Linux 2.6.28 on Fit-pc  computer which based on
AMD Geode LX800 500MHz (Chipset AMD CS5536).
I want to utilize the GPIOs (as well as SMbus) to control some custom peripherals.
The kernel 2.6.28 already has cs5535_gpio driver, but I've patched
it to get the corresponding devices in /dev automatically .
Now I have the following devices:
Now I need to go to the next step.
What is the "proper way" to work with GPIO/SMbus from within Linux?
Could sombody advise and/or refer documentation/software/drivers?