Hi all, So to me it looks like the discussion is going in circles a bit, hence let me drop my maintainer-opinion here: 1. Matthew's patch series here looks reasonable, and if it fixes a bunch of systems (which it seems to) it has my Ack and imo should go in. If acpi maintainers can smash their Ack onto the acpi parts I'd very much like to merge this into drm-intel-next, that should give us the most coverage for intel systems. Len, Rafael, are you ok with the acpi part of this and merging it through drm-intel-next? 2. Imo the current amount of quirking we expose to users (we have kernel options to disable the acpi interface, blacklist platform modules, all backlights can be tested through sysfs and on top of that xf86-video-intel has an xorg.conf to select the backlight used by the driver). I haven't spotted a compelling reason in this thread to add another one, what we have seems to be good enough to debug backligh issues. 3. Also, adding yet another backlight quirk mechanism isn't gonna magically fix broken systems. We _really_ should strive to make this just work and not offer the angry user another roll of duct-tape for free. 4. The currently established priority selection for backlights of platform > firmware > raw seems to be good enough. Note that the explicit list in xf86-vidoe-intel is only used as a fallback for really old kernels which do not expose this information. We could probably rip it out. 5. We've recently looked at opregion again and couldn't spot a hint. Unfortnately it looks like both noodling better information out of Intel and trying to publish an updated opregion spec seem to be losing games :( We'll keep on trying though. Aside at the end: If the gnome tool indeed has its own backlight code and doesn't just use that as a fallback if the xrandr backligh property isn't available, then that's just a serious bug in gnome and should be fixed asap. But imo that's not something we should try to (nor do I see any way how to) work around in the kernel. Cheers, Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch
