lsusb -t

/:  Bus 001.Port 001: Dev 001, Class=root_hub, Driver=ehci-pci/2p, 480M
    |__ Port 001: Dev 002, If 0, Class=Hub, Driver=hub/4p, 480M
/:  Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/10p, 480M
    |__ Port 002: Dev 002, If 0, Class=Vendor Specific Class, Driver=rtl8xxxu, 480M
    |__ Port 004: Dev 003, If 0, Class=Audio, Driver=snd-usb-audio, 12M
    |__ Port 004: Dev 003, If 1, Class=Audio, Driver=snd-usb-audio, 12M
    |__ Port 004: Dev 003, If 2, Class=Audio, Driver=snd-usb-audio, 12M
    |__ Port 004: Dev 003, If 3, Class=Human Interface Device, Driver=usbhid, 12M
    |__ Port 007: Dev 004, If 0, Class=Human Interface Device, Driver=usbhid, 12M
    |__ Port 007: Dev 004, If 1, Class=Human Interface Device, Driver=usbhid, 12M
    |__ Port 007: Dev 004, If 2, Class=Human Interface Device, Driver=usbhid, 12M
    |__ Port 008: Dev 005, If 0, Class=Mass Storage, Driver=usb-storage, 480M
    |__ Port 009: Dev 006, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
    |__ Port 009: Dev 006, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
/:  Bus 003.Port 001: Dev 001, Class=root_hub, Driver=ehci-pci/2p, 480M
    |__ Port 001: Dev 002, If 0, Class=Hub, Driver=hub/6p, 480M
/:  Bus 004.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/2p, 5000M