I have just rebooted with kernel parameter video.use_bios_initial_backlight=0 and it does not behave differently from the default boot parameters.
So... I think I've finished following all of the steps in https://wiki.ubuntu.com/Kernel/Debugging/Backlight - I don't have a Thinkpad. - I checked and I am not using the thinkpad_acpi kernel module. Let me know if there is anything else I can do to debug. In particular, I would like to test a brightness applet as mentioned on that page but I cannot located it. Any idea what package it would be in or where I would find it? ** Package changed: xorg (Ubuntu) => xserver-xorg-video-intel (Ubuntu) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1214148 Title: Intel video: Display backlight cannot be changed on Toshiba Portege Z935 Status in “xserver-xorg-video-intel” package in Ubuntu: New Bug description: On my Toshiba Portege Z935-ST4N03 laptop, the display hotkeys and display brightness settings do not work at all. Symptoms: 1. When I use Fn F6 or Fn F7, I get a pop-up window that shows a light bulb and a slider, and the slider goes obediently up and down as I press F6/7. However, the brightness of the screen does not change as the slider indicator changes. 2. If I go into the Power Manager and set the display brightness to dim after a few seconds has passed, it doesn't dim. So it seems to me that the hotkeys are being recognized as a method to change the display brightness, but that the operating system is unable to change the hardware's actual screen brightness... I don't think it's a hotkey problem per se. I read through https://wiki.ubuntu.com/Kernel/Debugging/Backlight and I think I have the problem defined as: Backlight control does not work, but there are entries in /sys/class/backlight. Although I do not seem to have the Brightness applet on my system (I am running XFCE, so maybe that is why), but the Power Manager's brightness control is definitely not working. This is a recent install of Ubuntu, on a newly purchased laptop, so I have no idea whether it was working in previous versions of Ubuntu, kernels, etc. Sorry. I used the "ubuntu-bug" utility to report this bug, so I am not sure what else you need... but I am starting by attaching the Xorg log, and will attach the lspci output and other information shortly. I am also going to follow the rest of the debugging steps on the Backlight debugging page and attach the output as separate comments on this report. $ lsb_release -rd Description: Ubuntu 13.04 Release: 13.04 $apt-cache policy xorg xorg: Installed: 1:7.7+1ubuntu4 Candidate: 1:7.7+1ubuntu4 Version table: *** 1:7.7+1ubuntu4 0 500 http://us.archive.ubuntu.com/ubuntu/ raring/main amd64 Packages 100 /var/lib/dpkg/status ProblemType: Bug DistroRelease: Ubuntu 13.04 Package: xorg 1:7.7+1ubuntu4 ProcVersionSignature: Ubuntu 3.8.0-27.40-generic 3.8.13.4 Uname: Linux 3.8.0-27-generic x86_64 ApportVersion: 2.9.2-0ubuntu8.1 Architecture: amd64 Date: Mon Aug 19 14:01:34 2013 InstallationDate: Installed on 2013-06-17 (62 days ago) InstallationMedia: Xubuntu 13.04 "Raring Ringtail" - Release amd64 (20130423.1) MarkForUpload: True ProcEnviron: TERM=xterm PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: xorg Symptom: display UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1214148/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
