Another approach, there are 3 things that confirm that you have only USB2:
- USB High-Speed Bus
- Driver: EHCI
- Speed: 480Mb/s
USB 1.0 Low Speed (1.5 Mbit/s), Full Speed (12 Mbit/s)
USB 2.0 High Speed (480 Mbit/s)
USB 3.0 SuperSpeed (5 Gbit/s)
USB 3.1 SuperSpeed+ (10 Gbit/s)
Reference: https://en.wikipedia.org/wiki/USB
Open Host Controller Interface
The OHCI standard for USB is similar to the OHCI standard for
FireWire, but supports USB 1.1 (full and low speeds) only.
Universal Host Controller Interface
Universal Host Controller Interface (UHCI) is a proprietary
interface created by Intel for USB 1.x (full and low speeds).
Enhanced Host Controller Interface
Enhanced Host Controller Interface (EHCI-SPECIFICATION) is a
high-speed controller standard applicable to USB 2.0.
Extensible Host Controller Interface
Extensible Host Controller Interface (XHCI) is the newest host
controller standard that improves speed, power efficiency and
virtualization over its predecessors The goal was also to define a USB
host controller to replace UHCI/OHCI/EHCI. It supports all USB device
speeds (USB 3.1 SuperSpeed+, USB 3.0 SuperSpeed, USB 2.0 Low-, Full-,
and High-speed, USB 1.1 Low- and Full-speed).
Reference: https://en.wikipedia.org/wiki/Host_controller_interface_(USB,_Firewire)