On Mon, Mar 27, 2017 at 8:22 AM, Nandor Han [off-list ref] wrote:

Testing:

1. XRA1403 connected to iMX53 MCU
2. Export gpio from userspace
3. Verify that corresponding gpio directories are created
   in `/sys/class/gpio/gpioXX`
4. Export gpios from first and second bank as output
5. Set the output gpio pin to high/low and verify with the
   oscilloscope that gpio status is according with the configured
   value.

Do *NOT* use the sysfs for testing GPIO.
This is being phased out.

Use the tools in tools/gpio/* so that you exercise the
character device instead of the old deprecated ABI.

Yours,
Linus Walleij