unable to increase brightness once it's been decreased to its minimum

[Ariel Vardi]

On a sony vaio sz110, ubuntu dapper up-to-date:

Increasing the brightness using the Fn keys doesn't have any effect once it's been decreased to its minimum.

Step to reproduce:
1) Press Fn+F5
2) Notice brightness is decreased
3) Press Fn+F6
4) Notice brightness is increased
5) Press Fn+F5 until brightness is at its minimum
6) Press Fn+F6 to increase the brightness again
7) Notice it doesn't work anymore, the brightness is stuck at the minimum.

[Ariel Vardi (ariel-vardi)]

pressing the brightness+ button when this bug occurs yield the following input in acpid.log

[Mon Mar 27 13:52:19 2006] received event "sony/hotkey SPIC 00000001 00000011"
[Mon Mar 27 13:52:19 2006] notifying client 4330[111:111]
[Mon Mar 27 13:52:19 2006] executing action "/etc/acpi/sonybright.sh up"
[Mon Mar 27 13:52:19 2006] BEGIN HANDLER MESSAGES
/etc/acpi/sonybright.sh: line 18: echo: write error: Invalid argument
[Mon Mar 27 13:52:19 2006] END HANDLER MESSAGES
[Mon Mar 27 13:52:19 2006] action exited with status 2
[Mon Mar 27 13:52:19 2006] completed event "sony/hotkey SPIC 00000001 00000011"
[Mon Mar 27 13:52:19 2006] received event "sony/hotkey SPIC 00000001 0000003b"
[Mon Mar 27 13:52:19 2006] notifying client 4330[111:111]
[Mon Mar 27 13:52:19 2006] completed event "sony/hotkey SPIC 00000001 0000003b"

Pressing brightness- yields a similar output but with the error at line 8.

[Ariel Vardi (ariel-vardi)]

Please read bug #34802 as they are probably somehow related

[Matt Zimmerman (mdz)]

This *is* bug #34802.

[Ariel Vardi (ariel-vardi)]

err, meant bug #34801

[Paul Sladen (sladen)]

Hi Ariel, and thanks for your excellent list of each stage in the process. Could you paste the contents of:

  /proc/acpi/sony/brightness

at each stage in the sequence. And if you have a chance, try running through the contents of:

  /etc/acpi/sonybright.sh

manually. I notice in there that if going downwards and the LEVEL is at '1' (bottom of the scale) then we do:

  /usr/bin/spicctrl -b 0

do you have that program installed? I'm not sure what it's doing as there's nothing down to reverse it.

[Ariel Vardi (ariel-vardi)]

Hi Paul,

First off, I'd like to add that to use the Fn keys, I had to put my laptop to sleep twice. They were not working before (see bug #34801).
Now concerning this bug:

At the initial state, /proc/acpi/sony/brightness is set to 8.
Pressing Fn+F5 decreases this value by 1 and the actual brightness on the screen by 1 level.
Pressing Fn+F6 increases this value by 1 and increases the brightness as well.
Just to test, I tried increasing again. Nothing happened, the value didn't change, and the brightness either; which is good :)

Then I tried decreasing the brightness to its minimum. The value and the brightness were both decreased properly until I reached 1.
The next time, the brightness didn't decreased and the value changed to 38 (??). Increasing with the keys didn't anything at this point, the value stayed on 38 and the brightness stayed at its minimum.

by doing echo "5" > /proc/acpi/sony/brightness I managed to re-increase the brightness, and the keys worked again.

=>> spicctrl seems to input invalid values in /proc/acpi/sony/brightness. Here's a sample:
root@haifa:/home/ariel# spicctrl -b 0
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
38
root@haifa:/home/ariel# spicctrl -b 1
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
11
root@haifa:/home/ariel# spicctrl -b 2
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
27
root@haifa:/home/ariel# spicctrl -b 3
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
103
root@haifa:/home/ariel# spicctrl -b 4
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
12
root@haifa:/home/ariel# spicctrl -b 10
root@haifa:/home/ariel# cat /proc/acpi/sony/brightness
144

Whenever the value is higher than 8, the Fn keys cease to work.

Hope it helps.

[Ariel Vardi (ariel-vardi)]

Additional note: just noticed that my synaptic touchpad stopped working as well. It works as a simple touchpad now, i.e. no scrolling, etc..

[Albert Vilella (avilella)]

Yes. I can reproduce exactly the same behaviour on my Sony Vaio SZ1XP: send sleep twice (after first time Fn won't work), the strange initial Fn+brightness lowest/highest thingy... all of it.

[jkibble (jason-kibblewhite)]

Dell XPS M1330 also happens since latest update to ACPI in Gusty Dated 9/17/2007, functions worked correctly previously. also has the synaptics issue.

executing action "/etc/acpi/video_brightnessdown.sh"
action exited with status 0

Also of note the power manager the brightness control is now reversed. putting too 100% on battery is dimmest and like wise setting to lowest setting is brightest.

[Guido Conaldi (guido-conaldi)]

As today 09-21-2007, on my dell xps m1330 gutsy i386 still shows the same behaviour jkibble described.
In Gutsy Tribe 5 live brightness seems to work correctly.

[fmaste (fmaste)]

On my Dell Inspiron 9400, using Gutsy Beta live, I can only increase brightness by entering the Power management options (Increase automatically).

[lostangel78 (lostangel78)]

Or type the following command in a terminal:

xgamma -gamma 0.75

If that doesn't work you need to install xgamma from the repos.

I have posted my own solution here on setting it up:

http://ubuntuforums.org/showthread.p...42#post4168042

[lostangel78 (lostangel78)]

Sorry ... http://ubuntuforums.org/showthread.php?p=4168042#post4168042

[penalvch (penalvch)]

Ariel Vardi, please execute the following command, as it will automatically gather debugging information, in a terminal:
apport-collect 34802

[Launchpad Janitor (janitor)]

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