On Tue, Jun 11, 2019 at 09:55:30AM -0700, Brian Norris wrote: > On Tue, Jun 11, 2019 at 3:49 AM Daniel Thompson > <daniel.thompson@xxxxxxxxxx> wrote: > > This is a long standing flaw in the backlight interfaces. AFAIK generic > > userspaces end up with a (flawed) heuristic. > > Bingo! Would be nice if we could start to fix this long-standing flaw. Agreed! How could a fix look like, a sysfs attribute? Would a boolean value like 'logarithmic_scale' or 'linear_scale' be enough or could more granularity be needed? The new attribute could be optional (it only exists if explicitly specified by the driver) or be set to a default based on a heuristic if not specified and be 'fixed' on a case by case basis. The latter might violate "don't break userspace" though, so I'm not sure it's a good idea.