Hi On Thu, Jan 7, 2016 at 2:03 AM, Eric Curtin <ericcurtin17@xxxxxxxxx> wrote: > Also another query, could be a mini-side project for me as I'm a > beginner kernel dev when I have some spare time. Could we change the > minimum brightness value not to be off? 0 does not have to mean > backlight off from reading various things around the web: > > http://www.x.org/wiki/Events/XDC2014/XDC2014GoedeBacklight/backlight.pdf > > And to be honest having the ability to completely turn off the > backlight is a useless function and is probably unintended as discussed > in the github thread above also. You would need night vision googles to > read the screen in this state! I'm pretty sure the Windows driver does > not completely turn off the screen on minimum brightness either, no > need to have different functionality on different platforms especially > when this functionality isn't very useful. Whether '0' means 'off' or 'lowest brightness level' has been discussed several times. Sadly, we cannot change semantics without breaking user-space, so you better work around it. There have been several proposals to fix it, but I guess no-one cared so far. Anyway, both features (turning backlight off *and* lowest backlight level) _are_ used actively by user-space. Hence, both should be supported. Thanks David -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html