usb dfx info:
usb_id: 0
    conn_state      : 2
    fn_cnt          : 2
    fn_list[1]      : 1
    fn_list[2]      : 322

usb_id: 1
    conn_state      : 0
    fn_cnt          : 0

usb_id: 2
    conn_state      : 0
    fn_cnt          : 0

usb_id: 3
    conn_state      : 0
    fn_cnt          : 0

