2008 Brake issues

I had an ABS light on then it said trailer brake issue. Took it to a shop and had that fixed. Brakes felt squishy. Thought maybe they were glazed over so just had the front/rear rotors and pads replaced. Mechanic said the controller could be the issue. Thing is I don't know what part to even order. Can someone point me in the right direction? I've only had the truck for a few months and I've fixed everything except this issue and a TPMS issue.