Hi Arch-users !
I recently bought an Asus N56VM ( http://www.asus.com/Notebooks/Multimedi … ifications ).
=> optimus is working fine using Bumblebee
=> sound is working fine (alsa + jackd)
=> touchpad is working fine adding clickpad option in /etc/X11/xorg.conf.d10-synaptics.conf
=> keybord-backlight is working fine with https://github.com/ktoso/g73-keyboard-backlight-sh
The only problem I still have is the control of backlight of the screen.
I looked at the wiki page ( https://wiki.archlinux.org/index.php/Backlight ) and here is a summary :
The ACPI kernel interface for interacting with the backlight is typically be located here : /sys/class/backlight/acpi_video0/
Before, /sys/class/baklight was empty. Since i added "acpi_osi=Linux acpi_backlight=vendor" in /etc/default/grub, i've a folder here named "asus-nb-wmi", but i dont know if it is the "good" folder... Let's assume it is the good folder.
I go in /sys/class/backlight/asus-nb-wmi, and i try to edit brightness
# cat /sys/class/backlight/asus-nb-wmi/max_brightness 10
# echo 5 > /sys/class/backlight/asus-nb-wmi/brightness
Problem : This command "works" because it doesn't return an error, but it does not affect my screen => the brightness is maximum.
Even if I set /sys/class/backlight/asus-nb-wmi/brightness to 0, my screen is shining !
I also tried to use xbacklight, but as you can see, it doesn't work properly either.
# xbacklight No outputs have backlight property
So my question is simple : What can i do in order to control the backlight brightness ?
Feel free to give me all advices you can have : I'm interested in !
Thank you in advance <3 !
Last edited by JayCie (2012-09-11 14:21:00)
Check if /sys/class/backlight is empty, if you remove either the acpi_osi or acpi_backlight=vendor. My assumption is that one of the 2 kernel parameters isn't necessary.
Thanks a lot for responding !
Both of your responses are related with GRUB_CMDLINE_LINUX_DEFAULT, so let me show you exactly what is my config, and what i planned to do.
1) Currently, I have :
GRUB_CMDLINE_LINUX_DEFAULT="quiet elevator=deadline nomodeset acpi_osi=Linux acpi_backlight=vendor"
result : backlight is not working even if I have a folder "/sys/class/backlight/asus-nb-wmi"
2) I will first try :
GRUB_CMDLINE_LINUX_DEFAULT="quiet elevator=deadline nomodeset acpi_backlight=vendor"
=> result : same as 1)
3) then i will try :
GRUB_CMDLINE_LINUX_DEFAULT="quiet elevator=deadline nomodeset acpi_osi=Linux acpi_backlight=legacy"
=> result : the folder "/sys/class/backlight/asus-nb-wmi" is no more here. Of course, backlight is not working.
4) finaly, I will try :
GRUB_CMDLINE_LINUX_DEFAULT="quiet elevator=deadline nomodeset acpi_backlight=legacy"
=> result : same as 3)
I will try to test this today, and I will edit this post at each step in order to show my results.
When I'm done, I will post another message telling the result of my tests.
Thank you a lot for responding, and giving me advices. If you have another ideas, dont hesitate to post.
Last edited by JayCie (2012-09-12 12:53:10)
So here is my conclusion :
1) adding/removing acpi_osi=Linux is not affecting the final result
2) acpi_backlight=legacy removes the folder "/sys/class/backlight/asus-nb-wmi"
3) acpi_backlight=vendor addsthe folder "/sys/class/backlight/asus-nb-wmi", but backlight still not working.
Any other ideas ?
Wow Oo ! I will look at this, but i'm a bit scared by the idea of trying to "debug my bios" !