On Wed, Jul 31, 2013 at 9:00 AM, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote: > On Wed, Jul 31, 2013 at 06:32:47AM -0500, Felipe Contreras wrote: >> On Wed, Jul 31, 2013 at 12:14 AM, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote: >> > There's no mechanism for an OS to know whether or not a firmware >> > implementation will actually turn the backlight off at 0, so there's no >> > way the OS can define the lowest backlight state as anything other than >> > "May or may not turn the screen off". >> >> Yes there is; quirks. > > We aren't going to maintain a quirk list in order to support a guarantee > that was never made. "0" as a backlight level has potentially meant > "screen off" since the interface was first introduced. That doesn't change the fact that you were wrong, and there *is* actually a way. The fact that you don't want to go there doesn't mean it's not there. Here's another: device tree. There are ways to provide a consistent backlight interface to user-space. -- Felipe Contreras -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
