root@bpi-iot-ros-ai:~# lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 3: Dev 3, If 0, Class=Mass Storage, Driver=usb-storage, 480M
root@bpi-iot-ros-ai:~# lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=usb-storage, 480M
root@bpi-iot-ros-ai:~# lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 2: Dev 5, If 0, Class=Mass Storage, Driver=usb-storage, 480M
root@bpi-iot-ros-ai:~# lsusb -t
/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ohci/1p, 12M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=sunxi-ehci/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 4: Dev 6, If 0, Class=Mass Storage, Driver=usb-storage, 480M