# lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ohci-pci/10p, 12M
    |__ Port 2: Dev 2, If 0, Class=Hub, Driver=hub/4p, 12M
        |__ Port 4: Dev 9, If 0, Class=Mass Storage, Driver=usb-storage, 12M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/10p, 480M
    |__ Port 4: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 1: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage, 480M
        |__ Port 4: Dev 4, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M

# lsusb
Bus 001 Device 004: ID 0000:3821
Bus 001 Device 003: ID 18a5:0302 Verbatim, Ltd Flash Drive
Bus 001 Device 002: ID 05e3:0608 Genesys Logic, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 009: ID 1058:07a8 Western Digital Technologies, Inc. My Passport (WDBBEP), My Passport for Mac (WDBLUZ)
Bus 002 Device 002: ID 05e3:0610 Genesys Logic, Inc. 4-port hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

# lspci | grep USB
00:02.0 USB controller: NVIDIA Corporation MCP61 USB 1.1 Controller (rev a3)
00:02.1 USB controller: NVIDIA Corporation MCP61 USB 2.0 Controller (rev a3)