Comment 0 for bug 1914845

usb-c ports (4) are limited to 480 Mb/s. Should be 10 Gb/s
any device selecting a higher speed is ignored, no output to **dmesg --human --follow**
(bus usb4…6)
hardware is Intel Corporation JHL7540 Thunderbolt 3 USB Controller [Titan Ridge 4C 2018] [8086:15ec] (rev 06)

usb-a ports (2) work at 5 Gb/s
(bus usb1…2)

Hardware is Mac mini (2018) Macmini8,1
Linux is linux-generic-hwe-20.04
uname --release
5.8.0-36-generic

usb bus speeds:
for A in /sys/bus/usb/devices/usb*; do echo "$(basename $A): $(< $A/speed)"; done
usb1: 480
usb2: 10000
usb3: 480
usb4: 10000
usb5: 480
usb6: 10000

usb controllers:
find /sys/devices -regextype egrep -regex '.*/usb[0-9]+'
/sys/devices/pci0000:00/0000:00:01.2/0000:7b:00.0/0000:7c:02.0/0000:7e:00.0/usb5
/sys/devices/pci0000:00/0000:00:01.2/0000:7b:00.0/0000:7c:02.0/0000:7e:00.0/usb6
/sys/devices/pci0000:00/0000:00:01.1/0000:05:00.0/0000:06:02.0/0000:08:00.0/usb3
/sys/devices/pci0000:00/0000:00:01.1/0000:05:00.0/0000:06:02.0/0000:08:00.0/usb4
/sys/devices/pci0000:00/0000:00:14.0/usb1
/sys/devices/pci0000:00/0000:00:14.0/usb2

usb controller modules and drivers:
lspci -knns14
00:14.0 USB controller [0c03]: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller [8086:a36d] (rev 10)
    Subsystem: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller [8086:7270]
    Kernel driver in use: xhci_hcd
    Kernel modules: xhci_pci
lspci -knns7e:0
7e:00.0 USB controller [0c03]: Intel Corporation JHL7540 Thunderbolt 3 USB Controller [Titan Ridge 4C 2018] [8086:15ec] (rev 06)
    Subsystem: Intel Corporation JHL7540 Thunderbolt 3 USB Controller [Titan Ridge 4C 2018] [8086:0000]
    Kernel driver in use: xhci_hcd
    Kernel modules: xhci_pci
lspci -knns8:0
08:00.0 USB controller [0c03]: Intel Corporation JHL7540 Thunderbolt 3 USB Controller [Titan Ridge 4C 2018] [8086:15ec] (rev 06)
    Subsystem: Intel Corporation JHL7540 Thunderbolt 3 USB Controller [Titan Ridge 4C 2018] [8086:0000]
    Kernel driver in use: xhci_hcd
    Kernel modules: xhci_pci ​

**lsb_release -rd**
Description: Ubuntu 20.04.2 LTS
Release: 20.04