USB Ports on dock randomly stop working

I have a Dell Precision 5530 (basically their business version of the XPS 15) that I use with a Dell TB16 dock. I'm trying to debug an issue with the USB ports on the dock where they will work when I first plug the dock in, but then cease to work after some random period of time.

Random facts/beliefs I've determined:

  • I do not believe this is a hardware issue because I use this same dock with my personal XPS 15 and the same version of Ubuntu and don't encounter these issues
  • I believe it's something in the drivers or on the bus or something that's crashing with Ubuntu but I cannot figure out where and the logs (at least those returned by dmsg) do not contain any seemingly relevant information when devices stop
  • Almost always, some of the ports on the dock will continue to work (such as my webcam) while my keyboard and/or mouse will stop working
  • It usually always seems to be my keyboard first that will stop, followed by my mouse. The webcam seems to usually work, but there have been times where hangouts or Zoom hasn't been able to find it.
  • When the system is in this state, the devices in question do show up when I run lsusb
  • The monitors that are also connected to the dock never have issues with being detected or stopping
  • Usually removing and reinstalling the dock thunderbolt cable will reconnect the devices, but not always.

Any suggestions about where to go from here would be very much appreciated! Also if there's any other logs or anything that would be helpful, please don't hesitate to ask.


Solution 1:

I was having the same issues, but after disabling C-state in the BIOS as suggested in this reddit post the USB ports have been working without a hitch.