Device Tree • Re: gpio-poweroff questions

I2C1 uses GPIO2 & GPIO3, so using GPIO4 for gpio-poweroff is fine.

Does this work on other OS besides Raspberry Pi OS or is this YMMV?

Most OSs on Pi (those that are Linux-based) will support overlays because they inherit the Device Tree from the firmware, and its the firmware that applies the overlays.

set up GPIO 4 as an input with pulldown

That's an unusual choice - it's normally best to work with the power-up default of the pins to avoid glitches; GPIOs 0-8 pull up by default, and 9-27 pull down.

How are you hoping to use the input? The "export" option makes the GPIO available via sysfs, but that mechanism is deprecated now.

Can I either merge this with another overlay or load it with another overlay?

You can merge overlays, but is it necessary? All you should need is something like:

Statistics: Posted by PhilE — Tue Apr 23, 2024 7:53 am

---