PS3 controller doesn't work on Steam Deck

Whenever I try to plug my PS3 controller into a Steam Deck, the 4 LEDs keep flashing (with the occasional 1st and 4th turning off, then turning on again). I tried holding down the PS button but it doesn't connect. I can clearly see the controller listed as a "PS3 Controller" in the USB Device List from the desktop, but that's as far as it goes.

I have tried a different controller and that one worked fine, but I'd still like to somehow make the PS3 controller work since I prefer it. This is confusing me since linux is known for having immediate support for playstation controllers, I even tried it on Arch on my laptop and it connected just fine after pressing the PS button.

I can't make the controller show up in bluetooth device list either.

If anyone knows how to fix this, please let me know.