Changing brightness does not work in Ubuntu 11.10 after upgrading.

[khosro]

Hello,
I
After upgrading to Ubuntu 11.10 in my Sony Vaio Laptop(VGN-CS) and using Unity as a desktop environment,increasing and decreasing brightness via fn+f5 and fn+f6 does not worked any more.
I remember that i did not installed any NVIDIA driver in my laptop,
but it seems that Ubunut itself installed it in new version after upgrading to 11.10.
I also test http://ubuntuguide.net/change-screen...ntu-11-0410-10,but it does not work.
I can not worked with my laptop any more because brightness of my
screen is too high now.

Khosro.

[typhoon_tip]

If you open "Additional Drivers", does it say that the NVIDIA driver is currently activated ?

[khosro]

Yes ,it is.
I have attached a related screenshot picture.

Khosro.

[matt_symes]

Hi

What is the make and model of your latop and graphics card ?

Open a terminal and type

ls /sys/class/backlight

Copy and paste the results back here.

Then type

lsmod | grep video

and do the same thing.

Lastly

cat /proc/cmdline

Post back as well.

Kind regards

[khosro]

Hi matt_symes,
My laptop is Sony Vaio VGN-CS and graphic cards is NVIDIA.

The following is the commands and also output that you asked me to run :

khosro@khosro-laptop:~$ ls /sys/class/backlight
sony

khosro@khosro-laptop:~$ lsmod | grep video
uvcvideo               72711  0 
videodev               93004  1 uvcvideo
v4l2_compat_ioctl32    17083  1 videodev
video                  19412  0 

khosro@khosro-laptop:~$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-3.0.0-12-generic root=UUID=0095c4f7-3bae-490d-be19-3f907855199c ro quiet splash vt.handoff=7

Khosro.

[matt_symes]

Hi

Open a terminal and type

sudo nano /etc/default/grub

Enter your password. It will not be echoed to the screen.

Look for the line that says

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

and change it so it says

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

Press ctrl + o to save and ctrl + x to exit.

Then type

sudo update-grub

Reboot your PC and check your function keys. Post back if it doesn't work.

Edit: Just in case you missed it i have highlighted what you need to enter.

Kind regards

[khosro]

matt_symes,
I changed what you said,but unfortunately it does not work.
The following is my grub

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=vendor"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

[matt_symes]

Hi

Try

acpi_backlight=vendor

and not

acpi_osi=vendor

and then update grub again.

Kind regards

[khosro]

Still does not work.
my grub :

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
#GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=vendor"
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
GRUB_CMDLINE_LINUX=""

# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"

# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console

# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480

# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true

# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"

[matt_symes]

Hi

Lets check something out.

Open a terminal and type

ls /sys/class/backlight/sony

If you see a file in there called brightness then type

echo 5 | sudo tee /sys/class/backlight/sony/brightness

Enter your password. It will not be echoed to the screen.

If this lower the brightness the substituting 9 in the command above should set it back.

If there is no brightness file then post the output of

ls /sys/class/backlight/sony

Post back results.

Kind regards