What is the purpose of the gpio group?

There is a gpio group (at least on the Jetson Nano) that appears to have no purpose.

I have my “nano” user added to that group yet still, I have to sudo to access anything in sysfs (specifically the gpio).

nano@nano-desktop:~$ cat /sys/kernel/debug/gpio
cat: /sys/kernel/debug/gpio: Permission denied

Does anyone know how to fix this?

Update: okay, I CAN write/read to /sys/class/gpio/ and below. I just cannot access /sys/kernel/debug/gpio

Use “sudo” on any command accessing this. Example:
sudo ls /sys/class/gpio
sudo ls /sys/kernel/debug/gpio

You can drop into a root shell if you plan on chaining commands together and don’t want to run sudo each time:

sudo -s
...do several things...
exit

Basically, those files are not real files, and are direct connects to various drivers. Regular users are not allowed to do this.

You don’t need sudo for /sys/class/gpio. I suppose I was hoping that the Nvidia development people would amend the udev rule to allow user read permissions in /sys/kernel/debug/gpio in future releases.

I suspect they’re just being careful with permissions, which I appreciate. I think debugfs requires root on most (all?) Linux distros. Jetson.GPIO seems to work simply being in the gpio group.