As of Linux Kernel version 2.6.27 which was released this morning, there's a new way to drive gpio. This is called gpio-sysfs and it's advantage is that it works on any gpio on any chip on any platform. It looks the same whether you're accessing PB5 on an AVR32 or whether you're accessing a pin on an SPI I/O expander.
I've put documentation on the wiki, here: https://www.avrfreaks.net/wiki/in...
While I was at it, I've moved all the HowTos which weren't specific to the NGW100 out of the NGW100 page and on to the main page. Next to them I'm starting to assemble a simple, clear and concise list of peripherals and how to drive them under Linux. If you have experience, especially with I2C/TWI, Framebuffers or the ISI, please add to the pages there! Hopefully it'll be easier for people to find what they need.