On 12/03/2013 12:53 AM, Guillaume Millet wrote: > Hello, I report an issue, in attempting to follow the instructions at > https://wiki.ubuntu.com/Bugs/Upstream/kernel#KernelTeam.2BAC8-KernelTeamBugPolicies.Overview_on_Reporting_Bugs_Upstream > > [1.] 8086:2a42 [Asus UL80VT] Backlight control does not work with Intel > integrated card, but there are entries in /sys/class/backlight > > [2.] The screen brightness control has apparently never worked > off-the-shelf on this laptop, Asus UL80VT-A1, which is an NVIDIA Optimus > laptop (2 graphic cards). The use of the discrete Nvidia card is managed > by Bumblebee (https://wiki.ubuntu.com/Bumblebee). It used to work with > the workaround suggested at > http://wiki.daviddarts.com/Ubuntu_Maverick_on_the_Asus_UL30VT#Screen_Brightness > which modifies asus-brn-down.sh to use the "setpci" method. > Hotkeys are detected, showkey -s returns 0xe0 0x4c 0xe0 0xcc for Fn+F5 > and 0xe0 0x54 0xe0 0xd4 for Fn+F6. > When the hotkeys are triggered, there is no brightness change but the > KDE notification pops up with 3 or 4 levels. > > [X.] Other notes > $ ls /sys/class/backlight/ > acpi_video0 acpi_video1 intel_backlight > > $ cat /sys/class/backlight/intel_backlight/max_brightness > 2583660 > > $ cat /sys/class/backlight/intel_backlight/brightness > 121584 With v3.12, does the intel_backlight interface work? You can verify this by echoing some value to the brightness file and see if it has any effect. The value can be echoed is 0 - max_brightness. Be careful with very small values, it will black your screen. If it works, you can specify intel_backlight as the control interface for X by creating a xorg.conf file like this: $ cat /etc/Xorg/Xorg.conf Section "Device" Option "Backlight" "intel_backlight" Identifier "Card0" Driver "intel" BusID "PCI:0:2:0" EndSection -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
