“Believe it or not, when you use the PS4 Controller through the Steam API, it’s exactly the same as a Steam Controller,” Doucet said. “You make the exact same API calls, you only get actions, not inputs, and the Steam API takes care of everything.”
The picture above shows PlayStation icons, though it’s worth noting they’re mapped to the ABXY buttons of the Xbox One and Steam Controllers. It’s unlikely we’ll see an icon switch in-game unless the developer itself has programmed the game to do so.
Steam Controllers offer a number of customization options, and many players create configurations that you can download from Steam and use in your games. You can watch GameSpot’s video on whether the Steam Controller can effectively replace your keyboard and mouse. We’ve yet to see how the DualShock 4 will fare in the same role.
Doucet stated that while DualShock 4 support is coming first because of the aforementioned functionality overlap, other controllers are planned to get the same Steam configuration options. You can read the full talk on Gamasutra.
Back in August, Sony announced a wireless USB adapter for the DualShock 4, alongside bringing its streaming service PlayStation Now to PC. The adapter works in the same way as it does when connecting the PS4 controller to a PC via a wired USB connection. Not every game offers functionality for the DualShock 4, and this means that it won’t work with these games.