how to find out number of brightness levels supported by any given backlit keyboard via code?

["Gabriel M. Elder" <gabriel tekgnowsys com>]

Hi all,

A question for all the genius devs out there who are familiar with the internal guts and plumbing of the gnome architecture and power subsystem(s):

What is the preferred and/or most expedient way to find out, via code, how many brightness state levels any given keyboard with backlighting capabilities will support? Just for clarity, for instance, I'm typing on a usb keyboard that has four brightness state levels: 3 (100%), 2 (66.6%), 1 (33.3%), and 0 (off, emitting no backlight). I'm looking to either utilize or create a way to automatically discover or retrieve that information, in code.

I'm not necessarily looking for example code, per se. I just need to know what modules to look at, function calls that could be made, and/or objects that are responsible for maintaining this information (if extant) that could or should be queried. Ideally, some function call that returns an integer. Does something that simple or something like it exist?

I know there's a keyboard proxy object from somewhere that gets used in cc-power-panel.c, but I'm not very familiar with it, and perhaps I should be looking elsewhere. If someone could point me in the right direction, it would be a great time-saver.

tia,

- Gabriel    0:)