Re: [PATCH 0/3] XRA1403,gpio - add XRA1403 gpio expander driver

From: Linus Walleij
Date: Tue Mar 28 2017 - 21:50:58 EST


On Mon, Mar 27, 2017 at 8:22 AM, Nandor Han <nandor.han@xxxxxx> 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