Valve hass announced that they will be adding Dualshock 4 support to Steam. The upcoming update will make it easy for developers to integrate support for Sony’s controller into their games and Valve plans to add support for additional third-party controllers to the API in the future.
Here is a quick overview from Valve:
Believe it or not, when you use the PS4 Controller through the Steam API, it’s exactly the same as a Steam Controller. You make the exact same API calls, you only get actions, not inputs, and the Steam API takes care of everything.
Now, why start with the PS4 controller? Well, not only is it a really nice, high quality controller, but it’s also got a gyro and a touchpad, so it’s got a lot of overlapping functionality with the Steam Controller. Also, existing native support for the PS4 controller on the PC is a bit weak; in this case Steam itself is communicating directly with the device so everything that’s nice and reliable.