gnome-color-manager uses argyllcms to generate display profiles[1]. At the moment there is a big fat "Calibrate" button in the GUI, that just produces a cryptic error if the calibration device is not plugged in. The attached patch (for comments) adds a ARGYLL_CALIBRATION_DEVICE udev string for supported devices, and would allow gnome-color-manager to make the calibrate button insensitive when there is not supported hardware installed, and sensitive when the hardware is inserted. The alternative is for gnome-color manager to keep a list of the VIDs and PIDs itself, which isn't ideal as then the lists would get out of sync when the list of supported devices grows. Thanks, feedback welcome. Richard. [1] http://blogs.gnome.org/hughsie/2009/11/02/gnome-color-manager-progress/