[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
Matthew, the next step is to fully commit bisect from kernel 3.13 to 4.4 in order to identify the last good kernel commit, followed immediately by the first bad one. This will allow for a more expedited analysis of the root cause of your issue. Could you please do this following https://wiki.ubuntu.com/Kernel/KernelBisection ? Please note, finding adjacent kernel versions is not fully commit bisecting. Also, the kernel release names are irrelevant for the purposes of bisecting. It is most helpful that after the fix commit (not kernel version) has been identified, you then mark this report Status Confirmed. Thank you for your help. ** Tags added: kernel-bug-exists-upstream-4.8-rc4 ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Incomplete Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
4.8.0-040800rc4-generic No change I'm afraid. actual_brightness is changed with the function keys but has no effect. Backlight off when brightness is set to 0; otherwise on. Shouldn't I be reporting this upstream? ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Confirmed Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
Matthew, to keep this relevant to upstream, one would want to test the latest mainline kernel (now 4.8-rc4) as it is released. Could you please advise? ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Incomplete Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
ASUS X202E - same problem -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Confirmed Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
Thanks for the advice. I installed 4.7.0-040700.201608021801 and it doesn't make any difference. I did discover, though, that with either kernel, if you give intel_backlight a brightness of 0, the backlight switches off completely. ** Tags added: kernel-bug-exists-upstream ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Confirmed Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.7 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/v4.7 ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Tags added: needs-bisect ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: Incomplete Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
[Kernel-packages] [Bug 1608745] Re: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial
In the description I of course meant acpi_video0 and acpi_video1. -- 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/1608745 Title: Backlight uncontrollable on Samsung NP740UE3 since upgrade to Xenial Status in linux package in Ubuntu: New Bug description: Stopped working since I upgraded from 14.04 to 16.04 - now stuck at full brightness. The only subdirectory in /sys/class/backlight is intel_backlight and while the function keys control the value in actual_brightness it has no effect. If I boot with the previous kernel (3.13.0-34) there are two more subdirectories: acpi_video0 and acpi_video0. Either of these can be used to control the brightness by writing to the brightness entry, though the function keys no longer control it because they change values in intel_backlight instead. If I give the Xenial kernel the parameter acpi_backlight=video, those two subdirectories also appear and are controllable, though the function keys still try to control intel_backlight. Seems to be similar to https://bugzilla.kernel.org/show_bug.cgi?id=108971. From that I have tried acpi_backlight=native and acpi_backlight="!Windows 2012" and neither has any effect, nor does video.use_bios_initial or acpi_osi=Linux. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-31-generic 4.4.0-31.50 ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13 Uname: Linux 4.4.0-31-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USERPID ACCESS COMMAND /dev/snd/controlC0: matthew3526 F pulseaudio CurrentDesktop: Unity Date: Tue Aug 2 01:41:24 2016 HibernationDevice: RESUME=UUID=0adbc2db-fe30-4c7e-9189-6e241093a9db MachineType: SAMSUNG ELECTRONICS CO., LTD. 740U ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=11a96955-be22-4e0d-ba57-9da738ace79d ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.4.0-31-generic N/A linux-backports-modules-4.4.0-31-generic N/A linux-firmware1.157.2 SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2016-08-01 (0 days ago) dmi.bios.date: 02/26/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P07ABW.065.140226.dg dmi.board.asset.tag: No Asset Tag dmi.board.name: NP740U3E-S02UK 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.:bvrP07ABW.065.140226.dg:bd02/26/2014:svnSAMSUNGELECTRONICSCO.,LTD.:pn740U:pvrNP740U3E-S02UK:rvnSAMSUNGELECTRONICSCO.,LTD.:rnNP740U3E-S02UK:rvrSEC_SW_REVISION_1234567890ABCD:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A: dmi.product.name: 740U dmi.product.version: NP740U3E-S02UK dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1608745/+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
