Natty: Unable to adjust brightness for Acer Aspire 5731, requires reboot to reflect change

Not sure if this is related, but I've been fetching kernels from the Ubuntu Kernel PPA before previewing Ubuntu Netbook and later Kubuntu Natty on my ASUS UL30A.

The 2.6.38 kernels have had broken suspend/resume from the get-go, but versions since -4 have also had various degrees of broken Fn keys, i.e. broken ACPI support for my model. 2.6.38-3 works with Fn keys, 2.6.38-4 and up to the current -8 do not.

ATM, with -8, the broken keys are isolated to brightness up/down which, with acpi_listen running, will be logged *extremely slowly* (like once every 20 or 30 seconds) and block the queue for any other buttons being pressed (like sound up/down). Also, no KDE overlays will be shown for the brightness keys, and no change in brightness will take place. Here's me pressing keys:

daniel@daniel:~$ acpi_listen
video LCDD 00000086 00000000
video LCDD 00000087 00000000
video LCDD 00000086 00000000
video LCDD 00000087 00000000
hotkey ATKD 00000030 00000000
hotkey ATKD 00000031 00000000
hotkey ATKD 00000030 00000001
hotkey ATKD 00000031 00000001
hotkey ATKD 00000030 00000002
hotkey ATKD 00000031 00000002
hotkey ATKD 00000031 00000003
...

The first ones are the brightness keys (took well over a minute for those four lines to appear), the rest are volume keys.

I don't know if it's related to suspend/resume not working, but the issues arose simultaneously, and both are ACPI stuff, so I'm guessing they are :)

Also, if this is unrelated to the OT, I'll back off :)

Let me know if I can supply any useful output from somewhere. If nothing else, I think these might be of interest:

daniel@daniel:~$ dmesg | grep -i asus
[ 0.000000] DMI: ASUSTeK Computer Inc. UL30A /UL30A , BIOS 212 12/28/2009
[ 0.000000] ACPI: XSDT 00000000bdda0100 0008C (v01 _ASUS_ Notebook 20091228 MSFT 00000097)
[ 0.000000] ACPI: SLIC 00000000bdda0470 00176 (v01 _ASUS_ Notebook 20091228 MSFT 00000097)
[ 0.000000] ACPI: ATKG 00000000bddb1440 08024 (v01 _ASUS_ OEMATKG 20091228 MSFT 00000097)
[ 10.487942] asus_laptop: Asus Laptop Support version 0.42
[ 10.488151] asus_laptop: UL30A model detected
[ 10.498208] asus_laptop: Backlight controlled by ACPI video driver
[ 10.498785] input: Asus Laptop extra buttons as /devices/platform/asus_laptop/input/input5
daniel@daniel:~$ dmesg | grep -i lcd
[ 43.810726] ACPI Error: Method parse/execution failed [\_SB_.PCI0.VGA_.LCDD._BCM] (Node ffff8801376382f8), AE_AML_BUFFER_LIMIT (20110112/psparse-536)
[ 43.811048] ACPI Error: Method parse/execution failed [\_SB_.PCI0.VGA_.LCDD._BCM] (Node ffff8801376382f8), AE_AML_BUFFER_LIMIT (20110112/psparse-536)
[ 129.728303] ACPI Error: Method parse/execution failed [\_SB_.PCI0.VGA_.LCDD._BCM] (Node ffff8801376382f8), AE_AML_BUFFER_LIMIT (20110112/psparse-536)
  ... and a good 100 more of these ...

Thanks for the suggestions/info, I apologize for the delay in replying. I noticed the delayed/ignored Fn keys for brightness/sound, but that really isn't the problem. There is a disconnect in the kernel ACPI interface between the value stored for the desired brightness and what the hardware uses. For me the value is stored at /sys/devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/brightness, which is properly set by the various methods like the Fn keys. I have found that by setting the brightness value and then rebooting it will use the desired brightness after (warm) reboot. The brightness is also saved/restored upon suspend.

I am currently using 2.6.39-020639rc1-generic.

I tried using acpi_listen and the values for brightness are immediately updated even though the OSD does not appear most of the time. Here's an example:
# acpi_listen &
[1] 27934
# while sleep 1 ; do cat /sys/devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/actual_brightness ; done
4
video DD02 00000086 00000000
5
video DD02 00000086 00000000
6
video DD02 00000086 00000000
7
video DD02 00000086 00000000
8
video DD02 00000086 00000000
9
9
video DD02 00000087 00000000
8
video DD02 00000087 00000000
7
video DD02 00000087 00000000
6
video DD02 00000087 00000000
video DD02 00000087 00000000
4
video DD02 00000087 00000000
video DD02 00000087 00000000
video DD02 00000087 00000000
1
video DD02 00000087 00000000
video DD02 00000087 00000000
0

One thing that's disturbing here is that sometimes when I boot, I get a short glance of some ACPI and other things severely failing. I also have the odd behavior that if I use the brightness up and down keys shortly after grub, while the splash is showing, they work and continue to work throughout my entire session. If I don't use the brightness keys until in X, they do not work at all. ??!!?!

I'm having about the same problem in my Acer Aspire 5742Z. Hotkeys bring up the brightness window, and they modify the values of the files in the /sys/devices/virtual/backlight/acpi_video0 interface, but the actual brightness isn't really changed.

A minor difference with the original reporter is that any changes I make in the acpi_video0/brightness file don't work after reboot either.

Booting with "acpi=off" makes my brightness keys actually work again (am I losing anything more significant than brightness with "acpi=off"?).
On the other hand, "acpi_backlight=vendor" or "acpi.brightness_switch_enabled=0" don't have any effect, brightness doesn't work with them.

I upgraded by BIOS to the latest available firmware, and I'm attaching the DSDT.dsl output as suggested in https://wiki.ubuntu.com/BIOSandUbuntu#Buggy%20DSDT

Status changed to 'Confirmed' because the bug affects multiple users.

Would it be possible for you to test the latest upstream kernel? It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . If possible, please test the latest kernel (Not a kernel in the daily directory). Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag(Only that one tag, please leave the others). This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text.

If this bug is fixed by the mainline kernel, please add the following tag 'kernel-fixed-upstream-KERNEL-VERSION'. For example, if kernel version 3.1-rc9 fixed and issue, the tag would be: 'kernel-fixed-upstream-v3.1-rc9'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Thanks in advance.

I filed this bug: http://www.acpica.org/bugzilla/show_bug.cgi?id=931
and a bit later I read of a workaround in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/518002
which is to add "acpi_osi=Linux" in the kernel command line.
Then the brightness keys work, but there's no indicator popup window for the brightness, which is no big deal.

I can confirm this works as well, however it disables _all_ power
management and makes the system run very hot as well as not suspending
to RAM/hibernating.  --Not a desirable solution for a laptop.  I will
try the latest upstream kernel to see if it helps with ACPI enabled.

Regards,
Larry

On Fri, Nov 4, 2011 at 9:06 PM, Alkis Georgopoulos
<email address hidden> wrote:
>
> I filed this bug: http://www.acpica.org/bugzilla/show_bug.cgi?id=931
> and a bit later I read of a workaround in https://bugs.launchpad.net/ubuntu/+source/linux/+bug/518002
> which is to add "acpi_osi=Linux" in the kernel command line.
> Then the brightness keys work, but there's no indicator popup window for the brightness, which is no big deal.
>
> ** Bug watch added: www.acpica.org/bugzilla/ #931
>   http://www.acpica.org/bugzilla/show_bug.cgi?id=931
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/741223
>
> Title:
>  Natty: Unable to adjust brightness for Acer Aspire 5731, requires
>  reboot to reflect change
>
> Status in “linux” package in Ubuntu:
>  Confirmed
>
> Bug description:
>  By default whatever the brightness is set to upon power-up/reboot is what Ubuntu will use from GRUB on into the X session.
>  Reading through https://wiki.ubuntu.com/Kernel/Debugging/Backlight I disassembled the ACPI BIOS info (per https://wiki.ubuntu.com/BIOSandUbuntu#Buggy%20DSDT) and found entries for changing the brightness and the correct entries for the display itself.  /sys/devices/virtual/backlight/acpi_video0 exists for controlling the brightness but setting the values has no immediate effect on the brightness although the values are saved.   However, I have found that if I set /sys/devices/virtual/backlight/acpi_video0/brightness to a specific value it is used the next time the system is rebooted.  There is no /proc entry for the display adapter.
>  I am using the latest kernel for natty (2.6.38-020638rc8-generic #201103081151) available and have tried the latest 2.6.37-X kernels without any changes.  I have been unable to try the mainline 2.6.38 kernel due to the binutils change, preventing a clean compile.
>
>  ProblemType: Bug
>  DistroRelease: Ubuntu 11.04
>  Package: xorg 1:7.6~3ubuntu11
>  Uname: Linux 2.6.38-020638rc8-generic x86_64
>  Architecture: amd64
>  CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
>  CompositorRunning: None
>  DRM.card0.DP.1:
>   status: disconnected
>   enabled: disabled
>   dpms: Off
>   modes:
>   edid-base64:
>  DRM.card0.HDMI.A.1:
>   status: disconnected
>   enabled: disabled
>   dpms: Off
>   modes:
>   edid-base64:
>  DRM.card0.LVDS.1:
>   status: connected
>   enabled: enabled
>   dpms: On
>   modes: 1600x900
>   edid-base64: AP///////wAGr54QAAAAAAESAQOAJhV4CkUlnFtVnCcZUFQAAAABAQEBAQEBAQEBAQEBAQEBICtAkGGEFDBAKjMAftYQAAAYAAAADwAAAAAAAAAAAAAAAAAgAAAA/gBBVU8KICAgICAgICAgAAAA/gBCMTczUlcwMSBWMCAKALs=
>  DRM.card0.VGA.1:
>   status: disconnected
>   enabled: disabled
>   dpms: Off
>   modes:
>   edid-base64:
>  Date: Wed Mar 23 14:50:45 2011
>  DistUpgraded: Fresh install
>  DistroCodename: natty
>  DistroVariant: ubuntu
...

Larry Battraw, thank you for reporting this and helping make Ubuntu better. 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? Can you try with the latest development release of Ubuntu? ISO CD images are available from http://cdimage.ubuntu.com/releases/ .

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

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

Also, if you could test the latest upstream kernel available that would be great. It will allow additional upstream developers to examine the issue. Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag. This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text. Please let us know your results.

Thanks in advance.

I use Acer Aspire E1-571-6442 and Ubuntu 12.10 64 bit. I am unable to change brightness.

A.K.Karthikeyan, if you have a bug in Ubuntu, could you please file a new report by executing the following in a terminal:
ubuntu-bug linux

For more on this, please see the Ubuntu Kernel team article:
https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports

the Ubuntu Bug Control team and Ubuntu Bug Squad team article:
https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue

and Ubuntu Community article:
https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Please note, not filing a new report may delay your problem being addressed as quickly as possible.

Thank you for your understanding.