2.6 KiB
Custom user-space driver for the nreal Air to use it on Linux
Information before use
The code is provided as is and it's free to use. However the contributors can neither guarantee that it will work or that it won't damage your device since all of it is based on reverse-engineering instead of public documentation. The contributors are not responsible for proper or even official support. So use it at your own risk!
Inspiration and motivation
Because I've written a user-space driver before for a graphics tablet, I thought I might look into it. To my surprise video output, audio output (stereo) and audio input (microphone) already worked using drivers from the Linux kernel. So the only piece missing for full use was the IMU sensor data in theory.
A big help for implementing this piece of software was the source code and feedback from a custom driver for Windows here. Without that I would have needed to find out payloads my own. So big thanks to such projects being open-source!
Features
The driver will read, parse and interpret sensor data from two HID interfaces to feed custom event callbacks with data which can be used in user-space applications (for example whether buttons have been pressed, the current brightness level and the orientation quaternion/matrix/euler angles).
It's still a work-in-progress project since the goal would be to wire such events up into a compositor to render whole screens virtually depending on your 6-DoF orientation (without position).
Also keep in mind that this software will only run on Linux including devices like the Steam Deck, Pinephone or other mobile Linux devices.
Dependencies
You can build the binary using cmake and there are only two dependencies for now:
Fusion is a sensor fusion library which is integrated as git submodule. So when you checkout the
repository, just update the submodules to get it. The library libusb should be pretty common in
most Linux distributions repositories.
Build
The build process should be straight forward:
mkdir build
cd build
cmake ..
make
Run
It's easiest to run the software with root privileges. But theoretically it should be possible to adjust rules of your device to not need them for read/write access vis USB. It's definitely not planned to require that in the future (but for now):
sudo nrealAirLinuxDriver