The laptop model Packard Bell EasyNote LV suffer from the "black screen of death" on Linux with both Ubuntu Raring and Debian Wheezy. One fix is to boot with i915.invert_brightness=1, as this stop the drm subsystem from turning off the screen. Another fix is to boot with acpi_backlight=vendor, which disable the acpi backlight interface and yield to the intel_backligh interface that do not invert the brightness setting. When booting with i915.invert_brightness=1, the KDE subsystem powerdevil turn off the screen when the user log in, while with acpi_backlight=vendor the KDE subsystem do not. Because of this, I suspect the best fix is to either invert the acpi backlight handling, or to disable acpi backlight handling completely. I initially suggested to patch the i915 module in thread <URL: http://lists.freedesktop.org/archives/dri-devel/2013-June/039763.html >, but was asked to instead submit a bug report here to get the machine in question blacklisted from the acpi system. I've gathered some notes about the model in question on <URL: http://www.linlap.com/packard_bell_easynote_lv >. Please fix the linux kernel to get backlight on this machine working out of the box. :)
For all win8 systems, we are going to remove ACPI video's backlight control. I suppose this can solve your problem? The said patches are: https://patchwork.kernel.org/patch/2695411/ https://patchwork.kernel.org/patch/2695391/ https://patchwork.kernel.org/patch/2695401/
Possible to give those patches a test, Petter?
Updated patch in Rafael's linux-next branch: http://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git linux-next
Please attach acpidump.
I have a hard time believing this would be one of the inverted brightness machines. All the others have been gen4. Besides, if acpi_backlight=vendor fixes the problem, and backlight works all right with that, it's not an inverted brightness problem.
(In reply to Jani Nikula from comment #5) > I have a hard time believing this would be one of the inverted brightness > machines. All the others have been gen4. Besides, if acpi_backlight=vendor > fixes the problem, and backlight works all right with that, it's not an > inverted brightness problem. I agree. I would like to take a look at the acpi table, maybe there is some clue on what's wrong with ACPI's backlight control interface.
Created attachment 107284 [details] Output from acpidump Here is the requested apcidump output. Unfortunately I am not able to test kernel patches on the machine.
The asl code makes use of Intel operation region to do the backlight setting, I don't see any obvious problem with that at first glance. If you don't have access to that system, it would be hard to know what's the problem I'm afraid.
I'll close it as will_fix_later for now, feel free to re-open it once you can do tests on that system.
(In reply to Petter Reinholdtsen from comment #7) > Created attachment 107284 [details] > Output from acpidump > > Here is the requested apcidump output. Unfortunately I am not able to test > kernel patches on the machine. Petter, stumbled on this one again while digging into some old issues... did you try acpi_osi="!Windows 2012" kernel parameter?
[Jani Nikula] > Petter, stumbled on this one again while digging into some old > issues... did you try acpi_osi="!Windows 2012" kernel parameter? I just did, replacing the other acpi kernel parameter, and ended up with a black screen again.
Petter, did you ever try video.use_bios_initial_backlight=0 module parameter? Any help?