Bug 225061

- Can you attach an screenshot of the bug ? (https://bugs.kde.org/attachment.cgi?bugid=225061&action=enter) 
It could be a layouting issue....
Regards

Created attachment 40428 [details]
problem screenshot

Can you check the output of:

solid-powermanagement --commands 

And test if a different Plasma theme makes the slider visible?

I have just updated to RC3 and the issue is still here.

I have checked a number of plasma themes - most of them made no difference, but Air Opensuse did bring the slider back, but still it did not work - it alwasy jumps to 0 value when I change power profile values and dragging it with the mouse does not affect screen brightness. I can change the brightness with hardware buttons.


> solid-powermanagement --commands

Syntax:

  solid-powermanagement query (suspend|scheme|cpufreq)
             # List a particular set of information regarding power management.
             # - If the 'suspend' option is specified, give the list of suspend
             # methods supported by the system                                 
             # - If the 'scheme' option is specified, give the list of         
             # power management schemes supported by this system               
             # - If the 'cpufreq' option is specified, give the list of
             # supported CPU frequency policies

  solid-powermanagement set (scheme|cpufreq) 'value'
             # Set power management options of the system.
             # - If the 'scheme' option is specified, the power management
             # scheme set corresponds to 'value'
             # - If the 'cpufreq' option is specified, the CPU frequency policy
             # set corresponds to 'value'

  solid-powermanagement suspend 'method'
             # Suspend the computer using the given 'method'.

  solid-powermanagement brightness (set|get) 'value'
             # Set and get brightness options of the system.
             # - If the 'set' option is specified, the brightness is
             # set to 'value' (as a percentage)
             # - If the 'get' option is specified, the current brightness
             # is returned (as a percentage)'

Sorry, I meant:


solid-powermanagement brightness get

and possibly:

solid-powermanagement brightness set 100

solid-powermanagement brightness set 50

solid-powermanagement brightness set 0

Do these last three commands manipulate the screen brightness?

If not, can you look through the output of "lshal|grep panel" to see what HAL reports (and thus Solid uses).

Here is the output. I have started with the brightness set to maximum from hardware buttons, then after the 1st "set" command (though it was "set 100") the screen got dark and later "set" commands did not affect it, so everytime I call "set", the brightness goes to the low level.


benderamp@benderamp-hp:~> solid-powermanagement brightness get                                                                                                   
solid-powermanagement(29851)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"                                              
solid-powermanagement(29851)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.                  

Brightness is -2147483648%
benderamp@benderamp-hp:~> solid-powermanagement brightness set 100
Setting brightness to 100%                                        
solid-powermanagement(29862)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"
solid-powermanagement(29862)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.
benderamp@benderamp-hp:~> solid-powermanagement brightness set 50
Setting brightness to 50%
solid-powermanagement(29867)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"
solid-powermanagement(29867)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.
benderamp@benderamp-hp:~> solid-powermanagement brightness set 0
Setting brightness to 0%
solid-powermanagement(29872)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"
solid-powermanagement(29872)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.
benderamp@benderamp-hp:~> solid-powermanagement brightness set 100
Setting brightness to 100%
solid-powermanagement(29891)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"
solid-powermanagement(29891)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.
benderamp@benderamp-hp:~> solid-powermanagement brightness get
solid-powermanagement(29900)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-benderamp/ksycoca4"
solid-powermanagement(29900)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.

Brightness is -2147483648%
benderamp@benderamp-hp:~> lshal|grep panel
  info.capabilities = {'laptop_panel'} (string list)
  info.category = 'laptop_panel'  (string)
  laptop_panel.access_method = 'general'  (string)
  laptop_panel.brightness_in_hardware = true  (bool)
  laptop_panel.num_levels = 1  (0x1)  (int)

This looks like a problem in HAL or Solid. I'm reassigning it, so Kevin can have a look.

Same issue for me under KDE 4.4.1 openSUSE 11.2 Factory packages. I am missing the brightness slider, however when I click into the area to the right of the "Screen brightness" label, I can modify the brightness as if the slider was there. Thus, I think it is a UI issue and not one of the underlying subsystems.

I can confirm this problem (openSUSE 11.2, KDE 4.4.2 Factory packages, Aya and Oxygen plasma themes) and get exactly the same error message:

solid-powermanagement brightness get
solid-powermanagement(16883)/kdecore (KSycoca): Trying to open ksycoca from  "/var/tmp/kdecache-martin/ksycoca4"
solid-powermanagement(16883)/kdecore (KLibrary): The library "/usr/lib64/kde4/solid_hal_power.so" does not offer a qt_plugin_instance function.

Brightness is -2147483648%

Trying to set the brightness to a different level with "solid-powermanagement brightnes set" always turns it back to 0%. 
Changing the brightness with "xbacklight -set" works without problems.

From my point of view, this bug report describes two independent(?) problems: 
1. The brightness slider is only visible with the air-opensuse plasma theme
2. Changing the brightness via solid-powermanagement does not work.

this bug (or more exactly both problems described in my post above) is still present in the kde 4.4.3 build from OpenSUSE.
kdebase-workspace is 4.4.3-443.1 from 
http://download.opensuse.org/repositories/KDE:/KDE4:/Factory:/Desktop/openSUSE_11.2/

Are all the people seeing this bug using openSUSE. Then this is probably caused by the downstream bug https://bugzilla.novell.com/show_bug.cgi?id=623459 
(see also https://bugzilla.novell.com/show_bug.cgi?id=615921 which is a duplicate of the above bug)

Marking as invalid after the last comment

Hi guys,

I do not think this bug should be treated as invalid, although it can be distribution i.e. suse specific. I have the same problem. And the problem is in
solid-powermanagement brightness function. Get and Set function just mulfunction. The open suse bug is about some graphical problems with themes.

What can be the reason? :( 

p.s. Everything works if I do: echo /proc/acpi/video/C098/C1AD/brightness 100.

Hi again!

after restart the problem disappeared... So probably the bug should remain closed :)

Roman