daniele@daniele-PC:~$ lsusb && lsusb -t 
Bus 001 Device 002: ID 0bda:818b Realtek Semiconductor Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 002: ID 040b:2014 Weltrend Semiconductor 
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ohci-pci/3p, 12M
    |__ Port 2: Dev 2, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
    |__ Port 2: Dev 2, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ohci-pci/3p, 12M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/6p, 480M
    |__ Port 3: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 480M