Brightness control also does not work on Samsung 730U3E. I'm running 15.04 with 3.19.0-15 kernel and having the same symptoms as reported and none of the listed kernel boot parameters show any effect.
-- 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/1380824 Title: Backlight not working on Samsung ATIV 8 laptop Status in linux package in Ubuntu: Incomplete Bug description: I have a 15" Samsung ATIV Book 8 laptop, np870z5e model from 2013. It features an Intel core-i7 cpu, and integrated Intel Hd4000 video card and also an ATI Radeon video card. According to Backlight debugging page[1], my case is "Backlight control does not work, but there are entries in /sys/class/backlight. " What works: Fn-F2, Fn-F3 keys works(Brightness down, brightness up), shows the brightness notification dialog, and also the /sys/class/backlight/intel_backlight/actual_brightness file changes too. It has no physical effect. It does not have any physical effect (brightness does not change), up until the brightness notification is zero (no bar on it), then the display switches off. raising the brightness switches the display back to the same brightness it was, and still not have any effect to the brightness. Semi works: Powering on the laptop starts with about 60% brightness. If I suspend-resume the laptop, it results 100% brightness. If I unplug the power cord (if it was plugged in when the laptop started), then it results 100% brightness. If I plug the power cord (if it was unplugged when the laptop started), then it results 100% brightness. I can't change the 100% brightness afterwards. What I have tried: a) xorg.conf file: # Fix Backlight issue Section "Device" Identifier "card0" Driver "intel" Option "Backlight" "intel_backlight" BusID "PCI:0:2:0" EndSection No effect. b) Kernel boot parameter in /etc/defaults/grub GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video.use_native_backlight=1" GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video.use_native_backlight=0" GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor" GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor" GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video.use_bios_initial_backlight=0" I tried each one, with a power off - power on cycle, but none of it had any effect. I doublechecked it (after boot), with cat /proc/cmdline. Changing the /sys/class/backlight/intel_backlight/brightness values, has no physical effect, although the file do change (checked with cat). I'm desperately trying to solve this issue, because the screen is always at full brightness, and burns my eyes out. (300cd/m2 screen is extremely bright). Any help is much appreciated. [1]: https://wiki.ubuntu.com/Kernel/Debugging/Backlight ProblemType: Bug DistroRelease: Ubuntu 14.10 Package: linux-image-3.16.0-21-generic 3.16.0-21.28 ProcVersionSignature: Ubuntu 3.16.0-21.28-generic 3.16.4 Uname: Linux 3.16.0-21-generic x86_64 ApportVersion: 2.14.7-0ubuntu5 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: lama 2528 F.... pulseaudio CurrentDesktop: Unity Date: Tue Oct 14 00:38:17 2014 InstallationDate: Installed on 2014-01-13 (273 days ago) InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) MachineType: SAMSUNG ELECTRONICS CO., LTD. 870Z5E/880Z5E/680Z5E ProcFB: 0 inteldrmfb 1 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-21-generic.efi.signed root=UUID=ba121a25-b094-49f5-96bf-ade769938060 ro quiet splash video.use_bios_initial_backlight=0 vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.16.0-21-generic N/A linux-backports-modules-3.16.0-21-generic N/A linux-firmware 1.135 SourcePackage: linux UpgradeStatus: Upgraded to utopic on 2014-10-08 (5 days ago) dmi.bios.date: 06/04/2013 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P02ADH.008.130604.SK dmi.board.asset.tag: No Asset Tag dmi.board.name: NP870Z5E-X01HU dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.board.version: SEC_SW_REVISION_1234567890ABCD dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 9 dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD. dmi.chassis.version: N/A dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrP02ADH.008.130604.SK:bd06/04/2013:svnSAMSUNGELECTRONICSCO.,LTD.:pn870Z5E/880Z5E/680Z5E:pvrP02ADH:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP870Z5E-X01HU:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 870Z5E/880Z5E/680Z5E dmi.product.version: P02ADH dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1380824/+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
