I thought I'd send the results of some experimentation of mine getting
an MGE UPS (Evolution) to talk to 2.5 ... basically it behaved after
some patches, though the "hidups" driver didn't.  They're all attached:

   - "hiddev-1.patch"  ... The default queue size was so small that this
     low-speed device couldn't queue up about 110 control requests
     (that many reports to check!) during init.

   - "hiddev-2.patch" ... Makes hid debug output more useful by
      (a) making it compile again;
      (b) adding lots of "Power Device" and "Battery System" reports,
          and putting all that data into the readonly data section;
      (c) actually printing the usage strings, if they're known;
      (d) printing a message when neither input nor hiddev claim
          the device ... likely something's wrong, like someone
          didn't configure in input subsystem or hiddev support.

   - "hiddev-3.patch" ... Teaches hiddev to expose the physical ID
     just like the input event framework does.  Useful to help sort
     out which UPS is which, so you won't power down the wrong set
     of servers by accident.