HID Updates For Linux 4.18 Add The Valve Steam Controller Kernel Driver
This Steam Controller kernel driver was developed by an individual and not sanctioned by Valve. This allows the Steam Controller to be treated as a normal input device and not limited to usage under the Steam client or when using a third-party user-space alternative like SC-Controller.
This kernel driver was developed via reverse-engineering and ends up exposing a virtual mouse, virtual keyboard, and custom HID device(s) to the system, allowing the controller to be happily used with any Linux application. The battery device is also exposed. This works both with the USB connection and wireless connectivity of the Steam controller. When the Steam client is loaded, it will still work and this kernel driver not interfere. This driver has been in the works the past number of months and has turned out quite well now reaching the mainline state and configurable via the HID_STEAM Kconfig switch.
The driver is part of HID updates for the Linux 4.18 kernel merge window. The other HID work this cycle includes Redragon Asura keyboard support, Windows 8.1 precision touchpad specification support, various Wacom device improvements, and more.
Linux 4.18 should debut by around the middle of August and will likely be the kernel version found in Ubuntu 18.10, Fedora 29, etc.