[ltp] x41 volume, mute buttons, and acpi

[Paul Fox]

marius wrote:
 > On Wed, Jun 27, 2007 at 03:28:27PM -0400, Paul Fox wrote:
 > > i don't do audio or video very often, so it was only recently
 > > that i realized that the special volume and mute keys (they're
 > > separate physical keys) aren't "hooked up" to anything via acpi.
 > 
 > That appears to be true.  Strangely, I notice that Fn-Home (increase
 > brightness) reports an event to acpid (ibm/hotkey HKEY 00000080
 > 00001010), but Fn-End (decrease brightness) doesn't.
 > 
 > > they do have a very real effect on output volume, but no effect
 > > on the alsa mixer levels.
 > 
 > They have an effect on alsa mixer levels on my laptop.  Actually, they
 > have a double effect:

sigh.  remind me never to buy another thinkpad.  they definitely don't
go to acpid on my X41, and there's no setting in the bios that lets
one control that behavior.  what idiocy.  :-/

 >   * the BIOS changes the hardware mixer volume level (you can observe it
 >     via /proc/acpi/ibm/volume)
 > 
 >   * they send keyboard events (I think thinkpad-keys from the
 >     hotkey-setup package is responsible for this), which are mapped to
 >     GNOME's global key bindings that change the volume (of the ALSA
 >     'master' mixer).

so you get two volume changes stacked on top of one another?  one from
the bios, and one from keybindings?

paul
=---------------------
 paul fox, pgf@foxharp.boston.ma.us (arlington, ma, where it's 85.1 degrees)