Add support for Steam Controller (2026)

[ZeptoBST]

I tried creating a device file for it, but no matter what I did IP would not detect the controller.

Running evtest also shows the controller is presented as keyboards and mices (even though it doesn't behave like one):

[pastaq]

I'm still waiting for my reservation in the queue, so it will be a while. It won't be as simple as adding a device config as it will need to be fully reverse engineered with an hidraw source driver and target device driver.

One project I am following currently is https://github.com/safijari/openpuck, which essentially allows you to do what InputPlumber does but on an external hardware device. It is a bit more niche than IP, but it has most of the data we will need.

[ZeptoBST]

SDL does support the controller, so I'm wondering if it'd be possible to make the controller part work (no track pads or back buttons).