GPIO on 9210 EL - looking for steps on how to access GPIO 1 - not visible when using GPIO Module

Embedded Devices
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2

If you can not access the pin it is probably taken by one of the enabled peripherals. In this case problably UART
0CTS UART A
Change your Uart to 2 wire only in kernel config and the pin should become free as GPIO

3

Thanks for the info.
I did finally do better reading of the documentation and realized I needed to correctly edit the makedevs.d resources.

I am having trouble trying to find appropriate examples of how to handle a pin to be interrupt driven. How to define the callback function.

4

There are two ways to work with GPIO

  1. using GPIO example app & sample gpio kernel module.
    Example app shows how to use interrupts.

  2. using sysfs (recommended):
    https://elinux.org/EBC_Exercise_11_gpio_Polling_and_Interrupts
    With actual C example here:
    https://developer.ridgerun.com/wiki/index.php?title=Gpio-int-test.c

Another good article here:
http://derekmolloy.ie/kernel-gpio-programming-buttons-and-leds/#Interrupts