Hi! I'm having similar anoying problem. Don't know if different enough to open a new ticket, but here it is.
When I switch on my laptop (a rebranded ECS laptop with Intel VGA) it's LCD brightness state change as: 1. Right after switching on: full bright (OK) 2. GRUB: full bright (OK) 3. Initng, but when the progress bar is waving from left to right and back: full bright (OK) -- I guess kernel does its initialization here 4. Initng, but when the progress bar resets and start growing as services are started: dims (NOT OK) -- I guess that some service, perhaps ACPI missconfiguration loading, dims the LCD 5. GDM: dimmed (NOT OK) 6. Desktop/GNOME Session: dimmed (NOT OK) After log in I run a script (as root) with the following line to bring brightness back to a suitable state: "echo 7 > /sys/class/backlight/acpi_video0/brightness" Although another way to get the same result would be: "echo 100 > /proc/acpi/video/GFX0/DD03/brightness" These bring brightness back to normal. But, after running any SDL application, like 'dosbox', the LCD dims again, so I have to re-run the above commands. So, I ran some more tests, they are: 6.1. Desktop/GNOME Session, SDL 'dosbox': dims (NOT OK) 6.2. Desktop/GNOME Session, my own SDL application: dims (NOT OK) Running the afore mentioned 'echoes' brings the brightness back to normal. 6.3. Desktop/GNOME Session, Screensaver: full bright (OK) 6.4. Desktop/GNOME Session, Suspend: full bright (OK) 6.5. Desktop/GNOME Session, Hibernate: full bright (OK) Some more details about my system: * Ubuntu Hardy 8.04 * PCI VGA Controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03) * Function keys for LCD brightness: they don't work, but I'm not concerned about them by now * Kernel 2.6.24-19-generic MY POINTS OF INVESTIGATION: * Why LCD dims at boot, apparently at services loading time? * Why the start of a SDL based application dims LCD? * Screensaver, suspending and hibernating cause no problem REMAINING TESTS: * ACPI boot parameter "acpi_apic_instance=2" (as pointed in boot messages) * ACPI boot parameter "acpi_osi=Linux" (as pointed in boot messages) As soon as I learn on how to use them with GRUB+initng. I'm attaching some logging files which may be helpful for debugging. Take some time looking at the 'ACPI Error' messages at 'dmesg.txt' and 'kern.log'. -- LCD Brightness on Laptop Always Set Very Low at Boot https://bugs.launchpad.net/bugs/12637 You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
