Finicky base USB ports

[Olwe]

I have an X201 with its base, and I have my mouse and keyboard plugged into the base's USB ports. Problems begin if I pop out the X201 (first put in suspend mode) and later pop it back in (and re-awaken from suspend mode): The mouse and keyboard don't work. I'm guessing the USB ports need to be re-initialized somehow? I'm on Ubuntu 15.04.