[Hardy] LCD Brightness Applet doesn't work properly

[Marcelo David]

LCD Brightness control using laptop keyboard shortcuts works perfect (Dell Inspiron 1501).
But LCD Brightness applet says "Brightness: 0%" always and if I attempt to scroll the bar to modify the brightness it freezes the whole gnome-panel at Hardy Alpha 4

[Miguel Ruiz (mruiz)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. I'm using Hardy Heron up to date and I followed the steps described above. The applet frozen my session and I had to restart the x-server :S

Thanks again and we appreciate your help.

Cheers!

[mellery (mellery)]

I see this on Hardy Alpha 5, there is also a transparent box that stays on my screen for a while, it flashes the brightness applet window before going away.

[Sebastien Bacher (seb128)]

The sysfs battery change broke GetBrightness on dell latitude computers. The issue is there since ubuntu using this change, http://gitweb.freedesktop.org/?p=hal.git;a=commitdiff;h=4541abd23fd02118a1a7f8b825aed338d2a5d638 on 0.5.10, the current git version has the same bug

$ dbus-send --system --print-reply --dest=org.freedesktop.Hal `hal-find-by-capability --capability laptop_panel` org.freedesktop.Hal.Device.LaptopPanel.GetBrightness
Error org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

when running this command the hald log gets the error

"[20311]: 23:39:42.424 [D] addon-dell-backlight.cpp:231: Received GetBrightness DBUS call
process 20311: arguments to dbus_message_get_args() were incorrect, assertion "(error) == NULL || !dbus_error_is_set ((error))" failed in file dbus-message.c line 1667.
This is normally a bug in some application using the D-Bus library."

Reverting the change

$ dbus-send --system --print-reply --dest=org.freedesktop.Hal `hal-find-by-capability --capability laptop_panel` org.freedesktop.Hal.Device.LaptopPanel.GetBrightness
method return sender=:1.100 -> dest=:1.107 reply_serial=2
   int32 6

and the hald log has

"[20436]: 23:41:43.964 [D] addon-dell-backlight.cpp:231: Received GetBrightness DBUS call
[20436]: 23:41:43.968 [D] addon-dell-backlight.cpp:82: Reading 6 from the AC backlight register"

[Sebastien Bacher (seb128)]

Thanks to Sjoerd Simons who figured the issue

addon-dell-backlight.cpp filter_function() is using

 AC = libhal_device_get_property_bool (halctx,
          "/org/freedesktop/Hal/devices/acpi_AC",
          "ac_adapter.present",
          &err);

or since the sysfs changes there is no "ac_adapter.present" key there and the same err variable is used when calling dbus_message_get_args later

[Danny Kukawka (danny-kukawka)]

see patch here:
http://thread.gmane.org/gmane.comp.freedesktop.hal/10866

[Danny Kukawka (danny-kukawka)]

*** Bug 14792 has been marked as a duplicate of this bug. ***

[Danny Kukawka (danny-kukawka)]

fixed: http://lists.freedesktop.org/archives/hal-commit/2008-March/004228.html

[Martin Pitt (pitti)]

This is actually a bug in the dell brightness backend of hal. The upstream fix works great, I'll applied it in bzr head.

[Martin Pitt (pitti)]

Uploaded to my PPA, testing feedback appreciated:

  https://launchpad.net/~pitti/+archive

[Christian Schürer-Waldheim (quincunx)]

Hello Martin,
i've just tested the package of your PPA.

Changing the brightness still doesn't work with this patch. The only thing which change is that guidance-power-manager doesn't hang that long any more as before (when I move the slider for the brightness) and that there are no error messages printed any more (as reported in Bug #198071).

Please advise if there is anything I can test further to debug this problem. Thanks!

[Christian Schürer-Waldheim (quincunx)]

PS: Packages I've used:
hal 0.5.10+git20080301-1ubuntu1~p Hardware Abstraction Layer
libhal-storage1 0.5.10+git20080301-1ubuntu1~p Hardware Abstraction Layer - shared library for storage devices
libhal1 0.5.10+git20080301-1ubuntu1~p Hardware Abstraction Layer - shared library

[Christian Schürer-Waldheim (quincunx)]

NB: I have a Dell Latitude D620, maybe this bug depends on the model of the computer too.

[Martin Pitt (pitti)]

Christian, are you using the ~ppa3 packages? The last bit of the version information was cut off unfortunately. Can you please check with

  dpkg -s hal | grep ^Version

Thank you!

[Christian Schürer-Waldheim (quincunx)]

Sorry that the version was cut off.
Yes, I am using the ~ppa3 packages:

dpkg -s hal | grep ^Version
Version: 0.5.10+git20080301-1ubuntu1~ppa3

[Martin Pitt (pitti)]

Christian,

since the new hal seems to fix it for all Gnome users I spoke to so far, I think it would make sense to open a new bug report for your case, so that we can track it properly. Thank you!

[Christian Schürer-Waldheim (quincunx)]

I've already opened a bug for the Dell-related problem of not being able the set the brightness - see Bug #198071.

Could you have a look at it, please?

[Launchpad Janitor (janitor)]

This bug was fixed in the package hal - 0.5.10+git20080301-1ubuntu1

---------------
hal (0.5.10+git20080301-1ubuntu1) hardy; urgency=low

  * Merge with Debian to pull in a current snapshot from upstream git head
    (upstream neglects doing a long-overdue 0.5.11 release). This pulls in two
    tons of bug fixes and reduces our insane stack of patches to a
    maintainable level again. (LP: #198295)
    - Uses MMC profile reading for CDs/DVDs. (LP: #66254)
  * Remove the following patches which are upstream now:
    - 01_proc_sys_batteries.patch
    - 02_sysfs_battery_serial.patch
    - 92_gxx43.patch
    - 94_batter-model_name.patch
    - 97_fix_power_info_via_sysfs.patch
  * Drop 80_allow_vfat_usefree.patch; Using 'usefree' VFAT mount option is not
    necessary with the current Hardy kernel any more.
  * Drop debian/patches/82_ignore_fixed_nonmedia.patch: Obsolete, GVFS treats
    fixed partitions correctly.
  * Tag and forward the subset of our remaining patches which have some kind
    of documentation and justification. Rename them to clean up patch order
    prefixes a bit.
  * 96_uinput_device_support.patch: Adapt to new upstream version.
  * Remaining Ubuntu changes:
   - debian/hal.init: Remove stray gparted-disable-automount.fdi on startup.
     Needs to be kept until Gnome #324220 is fixed properly.
     (LP #134712)
   - debian/hal.init: Unconditionally chown the directory in the init script.
     (LP #175525)
   - Ubuntu udev world order:
     + debian/hal.links: Remove rules symlink, we install the rules file
       directly into rules/.
     + debian/rules: Install udev rules into /etc/udev/rules.d/.
     + debian/hal.{preinst,postinst,postrm}: Transition code for changing the
       udev rule priority (see 0.5.8.1-3ubuntu7, needs to be kept until after
       Hardy's release).
   - debian/hal.preinst, debian/libhal1.preinst: Clean up doc directory
     symlinking when upgrading from Gutsy. Needs to be kept until after
     Hardy's release.
   - debian/rules: Enable MacBook (Pro) support on i386 and amd64. Add
     pciutils-dev build dependency.
   - debian/rules: Do not run stop init.d script for levels 1 and 6
     (TearDown).
   - debian/preferences.fdi: Disable automounting for fixed disks. On session
     startup it is not done anyway (since that disables the gnome-mount UI
     which would ask for authentication) and it leads to confusion when
     restarting hal while a session is running. (LP #138537)
   - Various bug fixes, see their patch headers:
     + 02_allow_ufs_ufstype.patch
     + 03_virtual_net_devices.patch
     + 04_read_brightness_not_actual_brightness.patch
     + 96_uinput_device_support.patch
     + ubuntu_01_ignore_single_slash_label.patch
   - 83_ssb_bus_support.patch: Add support for devices on the SSB bus; patch
     by Matthew Garrett (not applied upstream yet, this needs to update the
     spec, too).
   - 84_memstick_bus_support.patch: Add support for devices on the "memstick"
     bus; patch by Matthew Garrett (not reported upstream yet, this needs to
     update the spec, too).
   - 88_change_pm_quirk_policy.patch: Patch by Matthew Garret, undocumented,
     non-obvious purpose.
   - Use Polic...

[Christian Stöveken (excogitation)]

I just wanted to let so. know that the applet isn't working on Acer TM 8100 series as well.

When you hover you get: "Cannot get laptop panel brightness"

Should I open a seperate bug? (I always use the Fn keys anyways, but maybe so else wants it to work)

[der_vegi (m-may)]

Same problem here as well on a Inspiron 1501, amd64 with all updates applied. Maybe we should reopen the bug?

[Stiff (stiff.ru)]

Was the fix released or not?
i have this problem on kubuntu hardy 32bit with dell inspiron 1501 laptop. When i press brightness buttons, the indicator of guidance-powermanager shows, but the brightness not changes.

[Martin Pitt (pitti)]

Stiff, der_vegi, please have a look at bug 198071, which describes a similar problem for Dell laptops.

[Stiff (stiff.ru)]

There are some same bugs
https://bugs.launchpad.net/ubuntu/+source/hal/+bug/212733
https://bugs.launchpad.net/ubuntu/+source/hal/+bug/157607
and the problem was not solved here

[Marcelo David (marcelod)]

There's a work around at
http://www.ubuntu1501.com

regards,

El Mie, 11 de Junio de 2008, 8:59 am, Stiff escribió:
> Was the fix released or not?
> i have this problem on kubuntu hardy 32bit with dell inspiron 1501 laptop.
> When i press brightness buttons, the indicator of guidance-powermanager
> shows, but the brightness not changes.
>
> --
> [Hardy] LCD Brightness Applet doesn't work properly
> https://bugs.launchpad.net/bugs/191725
> You received this bug notification because you are a direct subscriber
> of the bug.
>

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Centro de Investigaciones Nucleares
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