Linux Adding Wake-On-Connect/Disconnect For USB4 Ports
When the system is run-time suspended, Intel has queued up a patch for allowing optional wake-on-connect or wake-on-disconnect.
This feature is optional and disabled by default. Additionally, as it doesn't make sense to necessarily wake the system for all USB4/Thunderbolt hot-plug events, the patch allows toggling the feature on a per-port basis. Under sysfs for the USB4 ports there is a new "wakeup" attribute for each port that can be optionally set to "enabled" if wanting to wake-up the system from run-time suspend on hotplug connect/disconnect events.
This Linux kernel support for USB4 wake-on-connect/disconnect is coming via this patch currently queued in the Thunderbolt's "next" branch ahead of the Linux 6.2 merge window next month.