8086:0416 [Asus N550JK] Backlight not adjusting either from Fn keys or from system settings

[Scott Pattinson]

system settings lock/brightness slider is absent.
processed all the steps in https://wiki.ubuntu.com/Kernel/Debugging/Backlight and none of the workarounds work.
/sys/class/backlight/intel_backlight/brightness echoing values to this DOES change the brightness though
results.log says that _BCL is broken though

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: linux-image-3.16.0-23-generic 3.16.0-23.30
ProcVersionSignature: Ubuntu 3.16.0-23.30-generic 3.16.4
Uname: Linux 3.16.0-23-generic x86_64
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: scott 2245 F.... pulseaudio
 /dev/snd/controlC0: scott 2245 F.... pulseaudio
CurrentDesktop: Unity
Date: Wed Oct 22 21:02:02 2014
HibernationDevice: RESUME=UUID=98c67a5a-4356-4e87-ac33-f59f8d45895a
InstallationDate: Installed on 2014-10-21 (1 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Alpha amd64 (20140923)
MachineType: ASUSTeK COMPUTER INC. N550JK
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-23-generic.efi.signed root=UUID=74c1b47c-6afc-49a0-8c0f-6de00ad61bb8 ro quiet splash video.use_bios_initial_backlight=0 vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.16.0-23-generic N/A
 linux-backports-modules-3.16.0-23-generic N/A
 linux-firmware 1.136
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/11/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: N550JK.207
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: N550JK
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrN550JK.207:bd08/11/2014:svnASUSTeKCOMPUTERINC.:pnN550JK:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnN550JK:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.name: N550JK
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.

[Brad Figg (brad-figg)]

This change was made by a bot.

[penalvch (penalvch)]

Scott Pattinson, thank you for reporting this and helping make Ubuntu better. Could you please test the latest upstream kernel available from the very top line at the top of the page (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested exactly shown as:
kernel-fixed-upstream-3.18-rc1

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description.

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Scott Pattinson (spattinson)]

fwts -i
brightness: Interactive LCD brightness test.
--------------------------------------------------------------------------------
Test 1 of 3: Observe all brightness changes.
PASSED: Test 1, Backlight intel_backlight set to dim level.
PASSED: Test 1, Backlight intel_backlight set to bright level.

Test 2 of 3: Observe min, max brightness changes.
PASSED: Test 2, Backlight intel_backlight was observed going from dim to bright.

Test 3 of 3: Test brightness hotkeys.
FAILED [HIGH] BrightnessNoHotKey: Test 3, Did not detect ACPI hotkey event.
FAILED [HIGH] BrightnessNoHotKey: Test 3, Did not detect ACPI hotkey event.

[Scott Pattinson (spattinson)]

I ran apt-get update and I also installed https://launchpad.net/~indicator-brightness/+archive/ubuntu/ppa and now the brightness slider is present in the applet and works. So I now have a workaround to easily change brightness.

the Fn brightness keys do not work and is confirmed from the fwts -i test that the ACPI hotkey is not being detected. The kernel was updated to the one mentioned in tags before fwts was run.

for clarity:
updated kernel: - no change
fwts -i :- results above
apt-update ; installed indicator brightness :- slider now present in applet and indicator brightness panel app works

remaining issue: fn hotkeys not detected

[penalvch (penalvch)]

Scott Pattinson, the issue you are reporting is an upstream one. Could you please report this problem to the appropriate mailing list (linux-acpi) by following the instructions _verbatim_ at https://wiki.ubuntu.com/Bugs/Upstream/kernel ?

Please provide a direct URL to your e-mail to the mailing list once you have made it so that it may be tracked.

Thank you for your understanding.