[rpi] Help Adding new GPIO Button

Hello all,

Sorry if this is foolish question, but I'm having a lot more trouble doing this than I expected

Basically, I have a Raspberry Pi Zero running OpenWRT 19.07.3 and I want to add an on-off switch with the GPIO pins. Following this I managed to see the state of the switch and all that; however, I do not know the next step to using it in OpenWRT.
Looking at the relating documents about adding buttons, they seem to all expect your button to be named in the system, whereas doing cat /sys/kernel/debug/gpio would show my added switch simply as "sysfs".

At this point I think that I have to change the .dtb file; however, I cannot find where to modify this in the source.

Thanks for any help!

Welp, simply adding
to /boot/config.txt got it to work for an on-off switch.

Regardless, I'd like to know what steps would need to be taken to add a button that was not built in, as part of an overlay like that.

related no takers yet...