[Bug 279163] Re: LCD backlight brightness control only works until boot starts
Fixed with kernel boot option "acpi_osi=" (without quotation marks). ** Changed in: acpi-support (Ubuntu) Status: New => Fix Released -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
"Good news, everyone..." Playing with the options explained here http://www.columbia.edu/~ariel/acpi/acpi_howto.txt I finally managed to get it done. I added the boot option acpi_osi= to my kernel line in /boot/grub/menu.lst and now it works. By default acpi_osi is used to hand over a string to the BIOS to pretend we are running Windows NT. Providing an empty string apparently leaves it as it is. -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
I'm now on Arch and with a very simple installation the error is the same. As soon as acpid is loaded the brightness cannot be changed anymore. cat /proc/acpi/video/IGD/LCD/info yields following output device_id: 0x0110 type: UNKNOWN known by bios: no -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
Is there any more information I shall provide? How can I try debugging it on my own? -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
This is the related thread with information what fixes I tried: http://ubuntuforums.org/showthread.php?p=5915703 -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
** Attachment added: "output of sudo dmidecode" http://launchpadlibrarian.net/18266165/output_of_sudo_dmidecode -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
** Attachment added: "output of sudo lspci -vvnn" http://launchpadlibrarian.net/18266129/output_of_sudo_lspci_-vvnn -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
This happened when trying to copy the acpi directory to tmp: cp: cannot open `/proc/acpi/event' for reading: Device or resource busy Hope it doesn't make a difference. ** Attachment added: "output of uname -a" http://launchpadlibrarian.net/18266104/output_of_uname_-a -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
[Bug 279163] Re: LCD backlight brightness control only works until boot starts
** Attachment added: "tarball of /proc/acpi" http://launchpadlibrarian.net/18266084/acpi.tar.bz -- LCD backlight brightness control only works until boot starts https://bugs.launchpad.net/bugs/279163 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
