The latest update to the Steam Client Beta, Valve's public test branch, adds additional support for the PlayStation 5's DualSense controller. The controller did already work with the Steam API, but without support for its bespoke features: here's how to get the DualSense set up on your PC.
Valve's update notes read: "Added additional support for the PS5 DualSense controller including LED, trackpad, rumble, and gyro functionality" and "Added a directional swipe mode for use with trackpads and gyro." That's more or less every DualSense feature bar the adaptive triggers.
This is of course in beta, and there are things Valve hasn't yet got round to. On-screen button prompts are still showing Xbox icons, as was the case when support was initially added, and users are reporting that rumble only works when the controller is wired.
The speed at which Valve has moved on the DualSense suggests that full support will not be far away: though quite how many Steam games might choose to take advantage of something like adaptive triggers is another question.