F16 KDE Volume/Brightness Keys

[Colin747]

Just installed F16 KDE and the screen brightness and volume keys don't seem to be working, when I press them it shows the brightness/volume being adjusted on the screen but the actual brightness/volume doesn't actually get ajusted

[tuxtard]

I can confirm this issue. I can also confirm that it is not hardware related. I tried FC 16 with KDE on many different laptops and on all of them I was unable to change brightness using FN keys in KDE. On the same devices I was able to change brightness levels using FN keys in both Gnome 3 and XFCE. Also, I can change brightness level in KDE by issuing the following command in the console:

echo "7" > /sys/class/backlight/acpi_video0/brightness

where 7 can be any number from 0 - 7, with 7 being the brightest. I even tried updating KDE to 4.8, but this issue is still present. I also tried OpenSuSE 12.1 on these laptops where I am able to change brightness in KDE as usual, which means that this issue is Fedora related.

I've also heard that this issue might be policy kit related and I tried the workaround provided in this post, but no luck. Here is my /var/log/messages output when I try to change brightness:

Mar 26 20:08:39 macerator dbus-daemon[913]: dbus[913]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Mar 26 20:08:39 macerator dbus[913]: [system] Activating service name='org.kde.powerdevil.backlighthelper' (using servicehelper)
Mar 26 20:08:39 macerator org.kde.powerdevil.backlighthelper: QDBusConnection: system D-Bus connection created before QCoreApplication. Application may misbehave.
Mar 26 20:08:39 macerator dbus-daemon[913]: dbus[913]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'

[Catastrophe]

same issue here on an asus laptop, is there any workaround or any bug report in which we can help?

the issue only happens when trying to set volume, screen brightness and keyboard backlight using their fn+F# combination (all working on Gnome) when going to sleep, toggling the wi-fi or turning off the screen (fn + F1/F2/F7 respectively) they work

[marriedto51]

I don't deny your experiences -- but the volume and brightness keys work as expected here: F16 KDE 4.8.1 on a Compaq CQ60 (using the Nvidia closed source drivers).

Is it worth checking that the keys generate the keysyms that KDE is expecting? You can check that with xev. For example, here when I press the [fn] brightness and volume controls, I get:

$ xev | grep keysym
    state 0x10, keycode 232 (keysym 0x1008ff03, XF86MonBrightnessDown), same_screen YES,
    state 0x10, keycode 233 (keysym 0x1008ff02, XF86MonBrightnessUp), same_screen YES,
    state 0x10, keycode 122 (keysym 0x1008ff11, XF86AudioLowerVolume), same_screen YES,
    state 0x10, keycode 123 (keysym 0x1008ff13, XF86AudioRaiseVolume), same_screen YES,

As a possible work-around, you can configure which keys will turn brightness up and down via System Settings -> Shortcuts and Gestures -> Global Keyboard Shortcuts -- choose "KDE Daemon" as the KDE component.

To configure the volume keys, choose KMix rather than KDE Daemon.

You might also need to make sure that KMix is running for the volume keys to work at all -- perhaps check the System Tray settings, and look for Volume Control under the Entries tab.

[Catastrophe]

@marriedto51

xev | grep keysym
    state 0x10, keycode 36 (keysym 0xff0d, Return), same_screen YES,
    state 0x10, keycode 121 (keysym 0x1008ff12, XF86AudioMute), same_screen YES,
    state 0x10, keycode 122 (keysym 0x1008ff11, XF86AudioLowerVolume), same_screen YES,
    state 0x10, keycode 123 (keysym 0x1008ff13, XF86AudioRaiseVolume), same_screen YES,
    state 0x10, keycode 237 (keysym 0x1008ff06, XF86KbdBrightnessDown), same_screen YES,
    state 0x10, keycode 237 (keysym 0x1008ff06, XF86KbdBrightnessDown), same_screen YES,
    state 0x10, keycode 238 (keysym 0x1008ff05, XF86KbdBrightnessUp), same_screen YES,
    state 0x10, keycode 238 (keysym 0x1008ff05, XF86KbdBrightnessUp), same_screen YES,
    state 0x10, keycode 232 (keysym 0x1008ff03, XF86MonBrightnessDown), same_screen YES,
    state 0x10, keycode 233 (keysym 0x1008ff02, XF86MonBrightnessUp), same_screen YES,

for the audio it was quite simple actually, turns out KMix had checked 'HDA NVidia Digital Stereo (HDMI)' as mixer, checking 'Internal Audio Analog Stereo' solved that part.

for the rest of the actions on the other hand... The shortcuts on the system settings for screen brightness are already set to the respective keys and nothing happens. and an option for keyboard backlight is glaringly missing.

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edit:
screen brightness solved, in my case i had 'xbacklight -set 60' on my autostart settings, unchecked it and it works. now for kb backlight......

[tuxtard]

I've just checked FC17, but still no luck. Only brightness keys don't work for me, every other Fn key do work. I will check if there is an existing bug report on bugzilla first, and if there is none I will post a proper bug report about this annoying issue.