Public bug reported: >From the upstream bug report: "Hardware Environment: Asus, N20A, all intel.
Problem Description: If the laptop loads the video module at boot time, /sys/devices/virtual/backlight/acpi_video0/brightness is created. However, it's all backwards, confusing applications like gnome-power-manager and the likes (well, that basically means hal). Echoing 0 to 'brightness' raises the backlight of this laptop to maximum. Echoing 13 to it, takes the backlight to a minimum. actual_brightness' seems to stay at 0 at all times. If I disallow the video module to be loaded at boot time, there's no backlight interface in /sys/class/backlight/*. But, nevertheless, the xbacklight utility and hal seem to be able to control the backlight just fine. In this latter case, withouth the video module loaded, xbacklight & hal handle the backlight correctly, i.e. less means lower backlight, and more means brighter backlight." More info in the upstream bug report, which I filed some time ago. It's fixed in mainline for 2.6.29, but won't be backported to vanilla. I think Ubuntu should include it, however, as it's a major annoyance and regression. Thanks! ** Affects: linux Importance: Unknown Status: Invalid ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Bug watch added: Linux Kernel Bug Tracker #12235 http://bugzilla.kernel.org/show_bug.cgi?id=12235 ** Also affects: linux via http://bugzilla.kernel.org/show_bug.cgi?id=12235 Importance: Unknown Status: Unknown ** Summary changed: - /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards + [asus] /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards -- [asus] /sys/devices/virtual/backlight/acpi_video0/brightness has it backwards https://bugs.launchpad.net/bugs/320874 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs