Cannot turn off keyboard backlight

[blurhy]

/sys/class/leds $ ls
asus-wireless::airplane input10::capslock input10::compose input10::kana input10::numlock input10::scrolllock input4::capslock input4::numlock input4::scrolllock phy0-led

There isn't any asus kbd backlight folder. `xset led off` doesn't work for me.
And I can only use fn to control volume (f1/f2/f3).

The leds kills my battery

$ sudo dmidecode -t 1; lsb_release -a

# dmidecode 3.1
Getting SMBIOS data from sysfs.
SMBIOS 3.0.0 present.

Handle 0x0001, DMI type 1, 27 bytes
System Information
 Manufacturer: ASUSTeK COMPUTER INC.
 Product Name: FX503VD
 Version: 1.0
 Serial Number: H9NRCX00M803374
 UUID: 524E3948-5843-3030-4D38-303333373441
 Wake-up Type: Power Switch
 SKU Number:
 Family: FX

No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Cosmic Cuttlefish (development branch)
Release: 18.10
Codename: cosmic

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: xorg 1:7.7+19ubuntu8
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Uname: Linux 4.18.0-10-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
.proc.driver.nvidia.gpus.0000.01.00.0: Error: [Errno 21] 是一个目录: '/proc/driver/nvidia/gpus/0000:01:00.0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 390.87 Tue Aug 21 12:33:05 PDT 2018
 GCC version: gcc version 8.2.0 (Ubuntu 8.2.0-7ubuntu1)
ApportVersion: 2.20.10-0ubuntu11
Architecture: amd64
BootLog: Error: [Errno 13] 权限不够: '/var/log/boot.log'
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: ubuntu:GNOME
Date: Mon Oct 15 17:13:35 2018
DistUpgraded: Fresh install
DistroCodename: cosmic
DistroVariant: ubuntu
DkmsStatus:
 nvidia, 390.87, 4.18.0-10-generic, x86_64: installed
 nvidia, 390.87, 4.18.0-9-generic, x86_64: installed
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Device [8086:591b] (rev 04) (prog-if 00 [VGA controller])
   Subsystem: ASUSTeK Computer Inc. Device [1043:1b90]
   Subsystem: ASUSTeK Computer Inc. GP107M [GeForce GTX 1050 Mobile] [1043:1b90]
InstallationDate: Installed on 2018-10-10 (4 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Beta amd64 (20180927)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 004: ID 0b05:1869 ASUSTek Computer, Inc.
 Bus 001 Device 003: ID 13d3:5666 IMC Networks
 Bus 001 Device 002: ID 8087:0a2b Intel Corp.
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: ASUSTeK COMPUTER INC. FX503VD
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-10-generic root=UUID=ad490863-aaf6-49d0-8508-514c07335e07 ro nouveau.runpm=0
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/03/2017
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: FX503VD.302
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: FX503VD
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.:bvrFX503VD.302:bd10/03/2017:svnASUSTeKCOMPUTERINC.:pnFX503VD:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnFX503VD:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:
dmi.product.family: FX
dmi.product.name: FX503VD
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.95-1
version.libgl1-mesa-dri: libgl1-mesa-dri 18.2.2-0ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.2.2-0ubuntu1
version.nvidia-graphics-drivers: nvidia-graphics-drivers-* N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.1-3ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-3

[Daniel van Vugt (vanvugt)]

These would be two different bugs:
  * Cannot turn off keyboard backlight.
  * Unable to control screen brightness via fn keys

Please reword this bug to only describe one of them. And then move the other issue into a new bug if you would like.

[Daniel van Vugt (vanvugt)]

Oh. Actually they might be the same bug if the problem is broken kernel support for your Asus control keys.

Does the screen brightness slider in the top-right menu work for you?

[Daniel van Vugt (vanvugt)]

Although if /sys/class/leds/*kbd* is missing then that's certainly a separate bug to the screen backlight problem.

Please split this bug into two, so that we have one bug report per problem.

[blurhy (blurhy)]

Yes,maybe these are two bug.Fn keys doesn't work and unable to control keyboard backlight.
But I can control the screen brightness via the top-reight control panel.

[Daniel van Vugt (vanvugt)]

Does changing your upower.service file fix the problem?

Remove: ProtectKernelTunables=true
And add: ProtectKernelTunables=false

If so then this may be related to bug 1796550 and https://gitlab.freedesktop.org/upower/upower/issues/73

[Daniel van Vugt (vanvugt)]

^^^
You also need to reboot after changing that.

[blurhy (blurhy)]

No,it's not useful.And I tried acpi_listen,still no output when i press Fn+Down

[Joseph Salisbury (jsalisbury)]

Did this issue start happening after an update/upgrade? Was there a prior kernel version where you were not having this particular problem?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.19 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19-rc8

[Sebastien Bacher (seb128)]

if you try to tweak it through upower/desktop controls it could be bug #1796550

[blurhy (blurhy)]

No,I don't have any /sys/class/leds/*::kbd_backlight* folder.

[Daniel van Vugt (vanvugt)]

Maybe merge with bug 1791372?

[Mario Vukelic (kreuzsakra)]

Bug #1791372 was fixed by update in Bug #1796550