famousgrumblecakes/gist:7da1a0ff117ceb110dd9b7147c168401

## gistfile1.txt
When running linux on a system with a Radeon 6900XT and connected to a Sabrent USB4 / TB3 KVM switch via the GPU's USB-C port, sometimes
USB devices connected via the dock will fail to connect to the PC. In this state, the display works but USB does not, so no keyboard / mouse / USB accessories.

This is seen on Fedora 43 (and 40 - 42) and is seen on Linux 6.18.9-200 and lower. I haven't figured out the exact conditions that trigger the problem,
but toggling between the inputs on the KVM while the PC is in the wrong state appears to be part of it.

This probably impacts other Radeon GPUs with USB-C ports (5X00, 6X00, 7X00; not 9070 boooo). I swear I've read a thread on this but I cannot find it.

Workaround:

echo '0000:0a:00.2' > /sys/bus/pci/drivers/xhci_hcd/unbind && echo '0000:0a:00.2' > /sys/bus/pci/drivers/xhci_hcd/bind

I dumped this in a udev rule to run every time the monitor is reattached:
# /etc/udev/rules.d/99-dock-rebind.rules
ACTION=="change", SUBSYSTEM=="drm", DEVPATH=="/devices/pci0000:00/0000:00:03.1/0000:08:00.0/0000:09:00.0/0000:0a:00.0/drm/card0", RUN+="/usr/local/bin/usb-rebind.sh"


This rule is obviously specific to my system, but you can use udevadm to get the device path for your kit, point being that rebinding the driver does the trick.
	When running linux on a system with a Radeon 6900XT and connected to a Sabrent USB4 / TB3 KVM switch via the GPU's USB-C port, sometimes
	USB devices connected via the dock will fail to connect to the PC. In this state, the display works but USB does not, so no keyboard / mouse / USB accessories.

	This is seen on Fedora 43 (and 40 - 42) and is seen on Linux 6.18.9-200 and lower. I haven't figured out the exact conditions that trigger the problem,
	but toggling between the inputs on the KVM while the PC is in the wrong state appears to be part of it.

	This probably impacts other Radeon GPUs with USB-C ports (5X00, 6X00, 7X00; not 9070 boooo). I swear I've read a thread on this but I cannot find it.

	Workaround:

	echo '0000:0a:00.2' > /sys/bus/pci/drivers/xhci_hcd/unbind && echo '0000:0a:00.2' > /sys/bus/pci/drivers/xhci_hcd/bind

	I dumped this in a udev rule to run every time the monitor is reattached:
	# /etc/udev/rules.d/99-dock-rebind.rules
	ACTION=="change", SUBSYSTEM=="drm", DEVPATH=="/devices/pci0000:00/0000:00:03.1/0000:08:00.0/0000:09:00.0/0000:0a:00.0/drm/card0", RUN+="/usr/local/bin/usb-rebind.sh"


	This rule is obviously specific to my system, but you can use udevadm to get the device path for your kit, point being that rebinding the driver does the trick.
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