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Screenshot of hardware report

I noticed that System report shows the wrong usage of USB 3.1 bus.

I have a 15-inch MacBook Pro from 2018 with i7, 2.2 GHz 6-Core

According to Apple, it has 4 USB 3.1 Ports.

At the time of the screenshot, I had connected:

  • Portable SSD via USB-C in one port
  • Monitor that also has a dock in one port
  • Ethernet cable adapter in one port (it shows in the Thunderbolt/USB4 section)
  • dock via USB-C that has my iPhone plugged in via one of their USB-3 Ports

System Reports shows that:

  • On one port I have a USB3.0 Hub with the Ethernet adapter - that is not actually the Ethernet adapter I have... it's actually the Ethernet port from the dock
  • On one port I have the portable SSD, one USB 2.0 hub, one 4-port USB 2.0 hub(the monitor)
  • One free port

Does anyone know what is happening?

Also, the dock that has my iPhone connected to it has all the ports listed as USB 3.0 ports but it shows as USB 2.0 Hub (even if I disconnect everything from it).

1 Answer 1

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What you are seeing is correct.

The USB “Hub” that you are seeing is not your hardware, but an I/O connecting point that is part of the USB Protocol.

From USB Protocol : Architecture, Working, Synchronisation, DataFormat & Its Applications *

I/O devices are connected to the computer through USB which is called as a hub. The Hub within the architecture is the connecting point between both the I/O devices as well as the computer. The root hub in this architecture is used to connect the whole structure to the hosting computer. The I/O devices in this architecture are a keyboard, mouse, speaker, camera, etc.

To put this simply, every I/O device you connect to your Mac (computer) gets attached to the USB hub even if directly connected. The “hub” in this case is created by USB controller. Since USB is backward compatible, it will create a hub for each USB specification (3.1, 3.0, 2.0, 1.1, etc.) in a device tree structure.

USB Device Tree

Image Source: https://binaryterms.com/


* El-Pro-Cus; https://www.elprocus.com/

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  • ok.. so because my docking station is split into 2 (ethernet being shown on the usb 3.0 hub and the other ports on the 2.0 hub) means that the manufacturer lied and the usb ports on the docking station are not in fact 3.0?
    – John
    Apr 4, 2023 at 17:22
  • No. You’re confusing the actual hardware hub(s) with the virtual hubs created by the USB controller for each device. If you have the latest USB3.2 port on your Mac and you plug in an ancient USB device, you’ll see a USB 1 hub in the device tree even though you didn’t plug in an actual hub
    – Allan
    Apr 4, 2023 at 17:25
  • but it shows it on USB2.0 event if there is nothing plugged into the dock
    – John
    Apr 4, 2023 at 17:43
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    You don’t necessarily have to plug something in for something to be connected. For example, prior to T2, the Apple (MacBook) keyboard and trackpad connected to the general USB bus. Your dock may have devices that show up on the bus without you plugging anything in
    – Allan
    Apr 4, 2023 at 17:46
  • ok but i am still confused.. you are saying that if i plug something that is working on 3.0 usb into my dock, that device will show on the 3.0 hub instead of 2.0 like it is now?
    – John
    Apr 5, 2023 at 7:49

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