On Fri, Apr 11, 2014 at 10:25:59AM +0200, Gerd Hoffmann wrote: > On Do, 2014-04-10 at 18:20 +0300, Michael S. Tsirkin wrote: > > On Thu, Apr 10, 2014 at 02:10:20PM +0200, Gerd Hoffmann wrote: > > > On Do, 2014-04-10 at 14:05 +0300, Michael S. Tsirkin wrote: > > > > On Thu, Apr 10, 2014 at 11:07:53AM +0200, Gerd Hoffmann wrote: > > > > > Device for sending non-input control messages to the guest. For now > > > > > this is only a single event: shutdown requests are sent as power > > > > > button > > > > > press to the guest. > > > > > > > > > > Possible other use is signaling sound volume changes to the guest (via > > > > > EV_ABS / ABS_VOLUME). I expect we'll find more over time. > > > > > > > > > > Signed-off-by: Gerd Hoffmann <kra...@redhat.com> > > > > > > > > Why not use a keyboard device for this? > > > > > > >From the guests point of view this is looks like a keyboard. A keyboard > > > with a single key: power. > > > > > > I prefer a clear separation between devices being feed from user input > > > and the control device which monitors other event sources (powerdown > > > notifier). > > > > > > There is no fundamental reason why this can't live in the emulated > > > keyboard though. > > > > > > cheers, > > > Gerd > > > > > > > Well I have a keyboard with volume keys - sleep and wakeup buttons too. > > Not power but that's not out of the realm of possibility. > > If we want to be able to pass that through, it should work as a > > virtio keyboard right? > > Sure. That is another story though. QKeyCode needs to learn those > keys, they need to be added to the mappings, and then they'll be handled > like any other key. > > > What I was thinking about is sending feedback about volume changes to > the guest is something completely different, let me explain in detail: > > What we have in spice today is that the guests volume change request is > passed to the spice client, which in turn forwards it to pulseaudio, > which then actually applies the volume setting to the audio stream. And > you can see the guests volume changes in the hosts mixer UI (sound > settings -> applications): change the volume in the guest and watch the > slider move. > > Today this is a one-way ticket. If you fiddle with the volume in the > hosts mixer ui the guest doesn't notice. A emulated volume wheel would > be a possible way to feedback volume changes on the host to the guest. > Note that it isn't that simple to implement as it need a spice protocol > extension too (and support in spice server + client of course). > > cheers, > Gerd
Or forward volume keys to guest through the virtio keyboard - then we don't need to emulate a volume wheel.
