backlight of my laptop is not working

[avinash]

i'm using emachines E725 i have installed ubuntu 11.04 and the backlight of my laptop screen stopped working as soon as I selected ubuntu to boot into from grub but when i select win 7 it work normally

[Timothy Mayoh (timothy-m-deactivatedaccount)]

Hello,

I have had a very similar problem with an eMachines E525 belonging to a friend, in the past.

To see if it is the same problem, can you please try the fix mentioned here and tell us whether it fixes it or not: http://ubuntuforums.org/showthread.php?t=1744809

Thanks in advance,
Timothy

[Seth Forshee (sforshee)]

avinash: In addition to what Timothy suggested, please run 'apport-collect -p linux 834970' to attach relevant data and log files to this bug report. Thanks!

[avinash (avula-avinash)]

first of all thanks timothy-m , i have tried the fix for my bug as mentioned in the thread 1744809
but i have to do it each time i boot is there any permanent fix for my bug

[Timothy Mayoh (timothy-m-deactivatedaccount)]

A permanent fix that worked in the case I tried was:

First open the script which automatically runs on startup by running this in terminal:
sudo gedit /etc/rc.local

Then just before "exit 0" add:
sudo setpci -s 00:02.0 F4.B=00

Finally, save that and close. Try restarting your computer - hopefully it should now automatically set the backlight to the correct brightness.

Hope it helps,
Timothy

[penalvch (penalvch)]

avinish, this bug was reported a while ago and there hasn't been any activity in it recently. We were wondering if this is still an issue? If so, could you please test for this with the latest development release of Ubuntu? ISO images are available from http://cdimage.ubuntu.com/daily-live/current/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux <replace-with-bug-number>

Also, could you please test the latest upstream kernel available (not the daily folder, but the one all the way at the bottom) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-v3.12-rc7

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]