Hello Sebastien, The gnome team came back with a "Not A Bug". Here's the reply (from Bastien Nocera [gnome-settings-daemon developer] ):
"The pkexec helper doesn't work but the brightness slider works. That means that gnome-settings-daemon works, and that it's using XRandR and not the pkexec helper to change the brightness. You can double-check that with: xrandr -q --verbose | grep -i backlight Furthermore, the pkexec helper isn't public API. The public API is through D-Bus." Any idea on how to fix this? Or is there a better way to do it? I tried with DBus as shown below, but had questionable success: dbus-send --session --print-reply --dest="org.gnome.SettingsDaemon" /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.SetPercentage uint32:percentage For Example: To set brightness to 30% dbus-send --session --print-reply --dest="org.gnome.SettingsDaemon" /org/gnome/SettingsDaemon/Power org.gnome.SettingsDaemon.Power.Screen.SetPercentage uint32:30 When the above-mentioned dbus-send command is issued, the slider in the GUI is correctly positioned to reflect the percentage requested, but the brightness is not always altered to match. Put another way, the dbus-send reliably only changes the slider position. However, the brightness is not always changed with the slider movement. The brightness changes sometimes, while sometimes remains unaltered. This happens randomly. Any suggestions? Any way to get pkexec to work? -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/1252507 Title: gsd-backlight-helper fails to change backlight Status in “gnome-settings-daemon” package in Ubuntu: New Bug description: In Saucy Salamander (Ubuntu 13.10), nothing happens when programmatically changing the backlight using the command: pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness 50 After issuing the above-mentioned command: 1. There is no difference in the screen brightness. 2. The slider in the "System Settings" -> "Brightness & Lock" remains unchanged. However, the value specified with --set-brightness argument is correctly reflected in the file: /sys/class/backlight/acpi_video0/actual_brightness and /sys/class/backlight/acpi_video0/actual_brightness Additionally, I'm using the proprietary Video driver for the AMD graphics accelerators from fglrx-updates. (I can't use the X.org X Server open source driver, because I get a lot of visual artefacts / screen refresh problems when I use it). Furthermore, adjusting the brightness directly from the GUI, using the slider in "System Settings" -> "Brightness & Lock" works correctly, changing the screen brightness, as is expected. This change in screen brightness can be confirmed by issuing the following commands: pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper --get-brightness and cat /sys/class/backlight/acpi_video0/actual_brightness and cat /sys/class/backlight/acpi_video0/actual_brightness Ubuntu Release: -------------------------- Description: Ubuntu 13.10 Release: 13.10 Package version: ----------------------------- gnome-settings-daemon: Installed: 3.8.5-0ubuntu11.1 Candidate: 3.8.5-0ubuntu11.1 Version table: *** 3.8.5-0ubuntu11.1 0 500 http://us.archive.ubuntu.com/ubuntu/ saucy-updates/main amd64 Packages 100 /var/lib/dpkg/status 3.8.5-0ubuntu9 0 500 http://us.archive.ubuntu.com/ubuntu/ saucy/main amd64 Packages Expected Behavior: ------------------------------- After issuing the command pkexec /usr/lib/gnome-settings-daemon/gsd-backlight-helper --set-brightness XX, the following should happen: 1. The screen brightness should increase or decrease as per the XX value specified. 2. The slider in the "System Settings" -> "Brightness & Lock" should change to reflect the new value. What Happens Instead: ----------------------------------- 1. There is no difference in the screen brightness. 2. The slider in the "System Settings" -> "Brightness & Lock" remains unchanged. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-settings-daemon/+bug/1252507/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
