Device Tree • Re: How to select a device tree on the basis of GPIOs?

Isn't that https://www.raspberrypi.com/documentati ... pio-filter

Kinda. GPIO based conditional filters are XOR and last one wins. That means one GPIO per overlay or combination of overlays except for the default.

Code:

[gpio0=1]dtoverlay=foo[gpio1=1]dtoverly=bar[all]

If both GPIO0 and GPIO1 are high you only get the bar overlay loaded. If GPIO0 is high and GPIO1 is low you get nothing.

Similarly,

Code:

[gpio0=1][gpio1=1]dtoverlay=baz[all]

Will load baz if GPIO1 is high, not, as you might expect, only if both GPIO0 and GPIO1 are high.

Code:

[gpio0=1]dtoverlay=foo[all][gpio1=1]dtoverly=bar[all]

Might load both if both GPIO are high but you'd need to test that as it's been a long time since I tried.

Statistics: Posted by funkpunkt — Tue Jun 25, 2024 6:53 am