Getting USB4 hotplug to work

This is being discussed here:

"How to hot plug an external USB-C hard drive in a Thunderbolt port?"
https://forum.puppylinux.com/viewtopic.php?t=16711

I configured the 6.12.81 kernel with CONFIG_USB4:

• Kernel 6.12.81 with CONFIG_USB4 — April 12, 2026

Arch Linux has, as usual, great documentation:

https://wiki.archlinux.org/title/Thunderbolt

Forum member rockedge reminded me, also need a udev rule. So have created /etc/udev/rules.d/99-thunderbolt.rules:

#20260417 ref: https://wiki.archlinux.org/title/Thunderbolt
# ref: https://forum.puppylinux.com/viewtopic.php?p=168112#p168112
ACTION=="add", SUBSYSTEM=="thunderbolt", ATTR{authorized}=="0", ATTR{authorized}="1"

Hopefully getting there!

EDIT:
After further reading of the Arch documentation, have renamed to /etc/udev/rules.d/97-thunderbolt.rules, with this content:

#20260417 ref: https://wiki.archlinux.org/title/Thunderbolt
# ref: https://forum.puppylinux.com/viewtopic.php?p=168112#p168112
ACTION=="add", SUBSYSTEM=="thunderbolt", ATTR{authorized}=="0", ATTR{authorized}="1"
ACTION=="change", SUBSYSTEM=="thunderbolt", RUN+="/usr/local/pup_event/thunderbolt-rescan.sh"

And /usr/local/pup_event/thunderbolt-rescan.sh has this content:

#!/bin/ash
echo 1 > /sys/bus/pci/rescan

This will be in the next release.        

Tags: easy