Not diagrams. My point being that 3 USB Controllers may mean actually 1 for the purposes of using it in Qubes OS. I saw situations like that: when all usb ports on the laptop are connected to a single controller, that it is also responsible for “wifi/bluetooth/touchpad/keyboard” - it is like having 1 controller after all, because other 2 controllers can do some internal stuff (thunderbolt/pci), that user cannot physically use anyway.
To match connectors and devices (wifi, bluetooth, touchpad, keyboard) with USB Controllers you can use manual tests like @unman proposed here: How to figure out which USB port goes to which USB controller? - #28 by unman
I am so insistent about this because it does matter for Qubes OS users, and users should definitely know what will they get as a certified laptop to avoid disappointments (congratulations on certification, by the way!).