Brightness control works with "video.use_native_backlight=1" added into grub
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1348020 Title: [Dell Latitude 3540] Unable to control brightness Status in “linux” package in Ubuntu: New Bug description: CIDL 201306-13866 Dell Latitude 3540 The brightness control does not work on this system Steps: 1. Install 14.04 + update (3.13.0-32), boot to desktop 2. Try to change the brightness by using the hotkeys 3. Try to change the brightness by using the "Brightness and Lock" applet Expect result: * Brightness control works fine Actual result: * Brightness level indicator changes with the hotkey, but not the brightness. * Brightness cannot be changed by the applet Debugging information: ubuntu@201306-13866:~$ ls /sys/class/backlight acpi_video0 intel_backlight ubuntu@201306-13866:~$ grep -r . /proc/acpi /proc/acpi/battery/BAT1/alarm:alarm: unsupported /proc/acpi/battery/BAT1/state:present: yes /proc/acpi/battery/BAT1/state:capacity state: ok /proc/acpi/battery/BAT1/state:charging state: charged /proc/acpi/battery/BAT1/state:present rate: 1 mA /proc/acpi/battery/BAT1/state:remaining capacity: 5900 mAh /proc/acpi/battery/BAT1/state:present voltage: 12972 mV /proc/acpi/battery/BAT1/info:present: yes /proc/acpi/battery/BAT1/info:design capacity: 5900 mAh /proc/acpi/battery/BAT1/info:last full capacity: 5900 mAh /proc/acpi/battery/BAT1/info:battery technology: rechargeable /proc/acpi/battery/BAT1/info:design voltage: 11100 mV /proc/acpi/battery/BAT1/info:design capacity warning: 590 mAh /proc/acpi/battery/BAT1/info:design capacity low: 177 mAh /proc/acpi/battery/BAT1/info:cycle count: 0 /proc/acpi/battery/BAT1/info:capacity granularity 1: 264 mAh /proc/acpi/battery/BAT1/info:capacity granularity 2: 3780 mAh /proc/acpi/battery/BAT1/info:model number: DELL G019Y35H /proc/acpi/battery/BAT1/info:serial number: 0C45 /proc/acpi/battery/BAT1/info:battery type: Li-Ion /proc/acpi/battery/BAT1/info:OEM info: SDI /proc/acpi/button/lid/LID0/state:state: open /proc/acpi/wakeup:Device S-state Status Sysfs node /proc/acpi/wakeup:P0P1 S4 *disabled /proc/acpi/wakeup:LID0 S3 *enabled /proc/acpi/wakeup:EHC1 S0 *enabled pci:0000:00:1d.0 /proc/acpi/wakeup:XHC S0 *enabled pci:0000:00:14.0 /proc/acpi/wakeup:PXSX S4 *disabled /proc/acpi/wakeup:RP03 S3 *disabled pci:0000:00:1c.0 /proc/acpi/wakeup:PEG0 S4 *disabled /proc/acpi/wakeup:PEGP S4 *disabled /proc/acpi/wakeup:PEG1 S4 *disabled /proc/acpi/wakeup:PEG2 S4 *disabled ubuntu@201306-13866:~$ dmesg | grep 'ACPI: Video' [ 11.036337] ACPI: Video Device [GFX0] (multi-head: yes rom: no post: no) ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-32-generic 3.13.0-32.57 ProcVersionSignature: Ubuntu 3.13.0-32.57-generic 3.13.11.4 Uname: Linux 3.13.0-32-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: ubuntu 1586 F.... pulseaudio CRDA: country TW: (2402 - 2472 @ 40), (3, 27) (5270 - 5330 @ 40), (3, 17), DFS (5735 - 5815 @ 40), (3, 30) CurrentDesktop: Unity Date: Wed Jul 23 23:35:09 2014 HibernationDevice: RESUME=UUID=bce2a764-eac9-4044-b879-caa497463b91 InstallationDate: Installed on 2014-07-24 (0 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417) MachineType: Dell Inc. Latitude 3540 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-32-generic.efi.signed root=UUID=1dd2f74b-d1f1-42e1-9c35-6675a578b71e ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.13.0-32-generic N/A linux-backports-modules-3.13.0-32-generic N/A linux-firmware 1.127.5 SourcePackage: linux StagingDrivers: rts5139 UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 08/06/2013 dmi.bios.vendor: Dell Inc. dmi.bios.version: A01 dmi.board.name: 0992HC dmi.board.vendor: Dell Inc. dmi.board.version: X01 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: A01 dmi.modalias: dmi:bvnDellInc.:bvrA01:bd08/06/2013:svnDellInc.:pnLatitude3540:pvrA01:rvnDellInc.:rn0992HC:rvrX01:cvnDellInc.:ct8:cvrA01: dmi.product.name: Latitude 3540 dmi.product.version: A01 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1348020/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
