Bug 99621

* Reproducible (1): Kernel 3.11.x (openSUSE 13.1 x86_64, KDE 4, clean standard set-up, always)
* Reproducible (2): Kernal 3.2.x (Debian 7, always)
* Symptom: On R60 and T60 series Thinkpads, volume and brightness changes through hotkeys are not acknowledged by the operating system 
* Fix: One-line command

On R60 and T60 Thinkpads, volume and brightness hotkeys are not interpreted correctly. The brightness hotkeys work, but the system does not acknowledge the change with its usual pop-up/overlay notifications (KDE4). The volume keys work, too, however there are again no pop-up/overlay notifications and the volume is changed using the acpi subsystem (which can be observed by monitoring /proc/acpi/ibm/volume) while the volume of pulseaudio remains untouched.  

On a freshly (re)booted system, I see the following:

# cat /sys/devices/platform/thinkpad_acpi/hotkey_all_mask
0x00ffffff
# cat /sys/devices/platform/thinkpad_acpi/hotkey_mask
0x008c7fff
# cat /sys/devices/platform/thinkpad_acpi/hotkey_recommended_mask 
0x008c7fff

The problem can be worked around by executing the following command with root privileges. This single change causes the hotkeys/buttons to work again as expected: 

# cat /sys/devices/platform/thinkpad_acpi/hotkey_all_mask > /sys/devices/platform/thinkpad_acpi/hotkey_mask 

Two bugs have been filed against openSUSE, both resolved WONTFIX: 

https://bugzilla.opensuse.org/show_bug.cgi?id=931543
https://bugzilla.opensuse.org/show_bug.cgi?id=849309

openSUSE-dev: "Right, it's a user's configuration. In the previous versions [of openSUSE], acpid package has set these values forcibly. Now the package was dropped, and this implicit setting is gone, too, unfortunately. I agree with the user-unfriendly module configuration, too. For that, rather please go asking upstream devs for improvements."

A detailed description of the identical problem and work-around in Debian 7 can be found here:

http://ebb.org/bkuhn/blog/2014/06/08/volume-hotkeys-thinkpad-t60.html