drmpp

DRM Client Library

Pre-Requisites

1. User must be added to the input group (if not root)

sudo usermod -a -G input $USER

Power cycle machine for group to be applied

2. Keymap File

Locate your compiled keymap file at $HOME/.xkb/keymap.xkb

You can create on a desktop machine running X11 or Wayland:

mkdir -p $HOME/.xkb
xkbcomp $DISPLAY $HOME/.xkb/keymap.xkb

Ignore any warnings

Frame buffer device access

Add user to the video group

sudo adduser $USER video
newgrp video

TTY Terminal

The system compositor has control of the DRM driver when active. You can suspend this access by switching to a TTY terminal.

On Fedora and Ubuntu you can switch to a TTY terminal using the keyboard combo:

Ctl+Alt+F3

You can switch back to the System GUI using:

Ctl+Alt+F2

Troubleshooting

If you see failure to initialize EGL display, add the user to the video group using:

sudo usermod -aG video $USER

If you see permission denied errors the user has not been added to the input group:

Failed to open /dev/input/event2 (Permission denied)
Failed to open /dev/input/event17 (Permission denied)