On Wed, Jul 31, 2013 at 12:52 PM, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote: > On Wed, Jul 31, 2013 at 12:46:04PM -0500, Felipe Contreras wrote: > >> 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. > > A quirk list will be incomplete, and as such there's no way to guarantee > whether or not a value of 0 will turn off the backlight. This is why the > interface doesn't make that guarantee, and why any userspace that > depends upon that behaviour is behaving incorrectly. There's no "guarantee" of anything. There is no "guarantee" that your computer won't freeze when you boot Linux. >> Here's another: device tree. > > There's no functional distinction between device tree and a quirk list > on x86 - they're both static data sources provided by something other > than the system firmware. As a result, they will both be incomplete. So? If something can't be perfect that means we shouldn't even try? If we can make the software behave consistently for 99% of the machines out there instead of only 90%, that's better. >> There are ways to provide a consistent backlight interface to user-space. > > No, there aren't. Yes there are. Not perfectly, nothing is ever perfect, but there are ways. -- 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
