DualSense Access Lost When Switching Linux Users
The Problem The multi-seat gaming setup runs Steam in a gamescope session as a systemd user service. The machine has two users: the gaming user who owns the gamescope service, and a separate work user. Both users are on seat0. Switching to the work user while the gamescope session is running caused the DualSense controller to stop responding in Steam. Why the Controller Goes Through hidraw Part 3 explains this in detail. The short version: TemporaryFileSystem=/dev/input in the gamescope service hides all evdev devices from the service process tree. Steam Input bypasses this entirely - it reads the DualSense through /dev/hidraw* (the raw HID interface) for full-feature support: adaptive triggers, haptics, gyro, touchpad. The evdev path is never used. ...