Comment 24 for bug 1381625

Yes, we can use that approach on unity-settings-daemon, with some minor modification to make xbacklight works.

My intention to make it configurable is because there was a Braswell laptop with a cheap panel, which needs at least 5% max brightness to make it barely visible. For OEM projects, to solve problems like that, a minimum brightness setting can be a generic and convenient way to make preloaded Ubuntu more polished.

That being said, most panel works just fine with brightness value 1 in my experience.