How to downgrade USB 2.0 480M speed to 12M?

Installing and Using OpenWrt Network and Wireless Configuration
1

Hello,

I'm using usbip on OpenWRT device to share an USB device over Ethernet to a remote client.

Everything works well with USB 1.1 compatible devices at 12 Mbit/s but unfortunately I have errors with an USB 2.0 device at 480 Mbit/s.

OpenWRT - server side :

[ 1724.705130] usbip-host 1-1: unlinked by a call to usb_unlink_urb()
[ 1724.712399] usbip-host 1-1: unlinked by a call to usb_unlink_urb()
[ 1855.569261] usbip-host 1-1: unlinked by a call to usb_unlink_urb()
[ 1855.576474] usbip-host 1-1: unlinked by a call to usb_unlink_urb()

Client side :

[70339.732896] vhci_hcd: unlink->seqnum 25811
[70339.733183] vhci_hcd: urb->status -131
[70339.740087] vhci_hcd: unlink->seqnum 25812
[70339.740390] vhci_hcd: urb->status -131
[70339.913720] vhci_hcd: unlink->seqnum 26131
[70339.913970] vhci_hcd: urb->status -131
[70339.920813] vhci_hcd: unlink->seqnum 26132
[70339.921107] vhci_hcd: urb->status -131

I would like to downgrade my USB 2.0 port or link from 480Mbit/s to 12Mbits/s but I haven't find the way to do that.

Any advice would be greatly appreciated,

Regards,

2

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/usb/usb.yaml#n44

3

Thanks for the link to the device tree related to USB, do you have an example on how to use it from cli interface?

Regards,

4

This is not something one can do from cli but rather needs patching the device tree and rebuilding a complete image.

The following methods usually won't work for embedded SoC integrated USB ports but that really depends on what exact OpenWrt device we are talking about.

https://bbs.archlinux.org/viewtopic.php?id=172005

5

What version of OpenWrt are you running?

6

I"m using OpenWRT 21.02 on a Mikrotik HexS and I would like, if it is possible, a more flexible solution than to rebuild the device tree.

7

There might be a USB hub that can be configured to use Full Speed instead of High Speed.

8

It's a good point but unfortunately I don't have any USB hub with an USB 1.1 port (12 Mbit/s) compatibility