dtoverlay is also a command

By chimo on (updated on )

Today I learned that “dtoverlay” is not only a property of the raspberrypi’s config.txt file, but also a command that can be run after bootup.

I was trying to get my raspberrypi (running Alpine Linux) to recognize my TSOP38238 IR receiver, but adding “dtoverlay=gpio-ir,gpio_pin=18” to the following files did not work:

  • /boot/usercfg.txt
  • /boot/config.txt
  • /boot/firmware/config.txt

Running the following command after booting up does make /dev/lirc0 appear, however:

k3rnel-pan1c:~$ doas dtoverlay gpio-ir,gpio_pin=18

Which is fine for my purposes since I only need the device to be present once in a while, not on every boot.

The command is available in the “raspberrypi-utils-dtmerge” package.