Potential to configure buttons with an overlay?

[shawaj]

Similar to here - https://github.com/notro/fbtft/blob/master/dts/overlays/rpi/tinylcd35-overlay.dts

[shawaj]

also see here - https://github.com/shawaj/linux/blob/a7eca81e0c579885f075549e19abae42408065b6/arch/arm/boot/dts/overlays/gpio-key-overlay.dts

and here - raspberrypi/linux#2329

This has now been implemented in the core kernel. You can call multiple buttons in the /boot/config.txt file using multiple calls to the overlay:

dtoverlay=gpio-key,gpio=13,keycode=59,label="KEY_F1"
dtoverlay=gpio-key,gpio=17,keycode=60,label="KEY_F2"
dtoverlay=gpio-key,gpio=22,keycode=61,label="KEY_F3"
dtoverlay=gpio-key,gpio=26,keycode=62,label="KEY_F4"
dtoverlay=gpio-key,gpio=27,keycode=63,label="KEY_F5"

Or on the command line at runtime like:

sudo dtoverlay gpio-key gpio=21 keycode=4 label="KEY_4" gpio_pull=0

Again, multiple calls can be done to this.

@francesco-vannini do you think we should add info about how to set buttons up like this to the README / docs somewhere? Could be pretty useful for navigating menus potentially?