http://bugs.winehq.org/show_bug.cgi?id=33017
--- Comment #19 from Stefan Leichter Stefan.Leichter@camLine.com 2013-03-22 12:55:30 CDT --- When your Garmin is connected and you run:
wine explorer
Do you see a drive corresponding to you Garmin? Do you find the file \Garmin\GarminDevice.xml on this drive. If you can not see the file, the detection will fail.