If the name of the mouse device starts with "/dev/ums", try to load the
ums module, and allow for up to five attempts to open the device, with
two-second pauses in between, to allow time for USB controllers and
devices to probe and attach. My Gigabyte P4 Titan 848P motherboard has
a total of 15 ports on four hubs hanging off four controllers, and needs
at least half of that ten-second allowance to get ready.

MFC after: 7 days