Accessing GPIO from User level - pca9670
I was hoping someone with a good understanding of the GPIO framework can shed some light into a problem.
I am working on a custom board (SBC - Xpedia 7073)
I need to trigger an output from a GPIO chip inside of the board. The chip is pca9670 and it is on the i2C bus.
I am running Ubuntu Desktop 11.04 (2.6.38-8-generic)
It would be great if I could use the GPIO framework to avoid having to write a kernel driver.
As far as I understand, Ubuntu already has the pcf857x driver as a kernel option.
I have read the /documentation/gpio.txt document, but it is not very clear to me.
The kernel does not seem to be recognizing the pca9670 since dmesg does not show the driver being able to find anything.
What steps should I follow? Do I need to configure the driver in someway before loading it?
I have tried loading the driver manually, but nothing changes
Any help or guidance is greatly appreciated.
Thanks a lot!!