On Monday, September 27, 2010 23:21:10 Masayuki Ohtake wrote:
> > You should be implementing support for the device using the
> > standard interfaces used by the other GPIO drivers in kernel.
> 
> We are now modifying our GPIO driver with standard interface.
> I've got a bit of problem.
> 
> I don't understand how userspace accesses to the driver.
> Let me know how to ? sysfs only ?

sysfs only.  look at GPIO_SYSFS in drivers/gpio/.  support the common GPIO 
framework and the userspace API is taken care of for you.
-mike