On Mon, 16 Jul 2007, Matthew Garrett wrote: > On Mon, Jul 16, 2007 at 11:46:26AM -0400, Dmitry Torokhov wrote: > > How do you know that this is a "passive keypress"? Can you put another > > (better) soundcard in a docking station? Woudl the firmware still > > control that card (doubtful)? Do we want the same keys to control that > > card's volume? > > This is absolutely possible. In that case I'd expect the hotkeys to > start controlling the card mixer's volume, but that's a policy decision > that would have to be taken in userspace by an application aware of > everything that's happened. The moment you screw up with the thinkpad builtin mixer, you are screwing with the emergency notification system (system beeps). They go *only* through that mixer, and their signal is not routed through the builtin AC97 (and probably not through HDA either) mixers. I would stay well away from trying to override what these buttons do. In fact, the thinkpad volume buttons are (in most thinkpads, I don't speak for the new *61 models, they may be different) the "button version" of a small volume dial near the headphone jack. They were NOT made to be used in any other way, they DO NOT work in any other way in Windows, and the firmware does NOT cooperate to let you use them in any other way. This whole issue is mainly caused by a refusal to understand this simple fact. THOSE BUTTONS ARE NOT GENERIC VOLUME CONTROL BUTTONS unless you hack the firmware on anything but the very newest X61, R61 and T61... and maybe even on them. (and if you hack the firmware, you can get thinkpad-acpi to do what you want with just the right sysfs setting). IMO, if you want to use hot keys to control the AC97/HDA/soundcard mixer volume in a typical thinkpad where the volume buttons are handled in firmware, just assign Fn+Insert and Fn+delete to VOLUME_UP and VOLUME_DOWN, they are right to the side of HOME/END (brightness up/down) anyway. Anyway, if the input layer is really not the place for "passive key presses", then my decision to not issue input events for such stuff is the correct one. Brightness can be notified through ACPI (ACPI 3.0b has standard events for this), or it could be done through an improved backlight sysfs class. It will require work either way, because you don't want ACPI video processing these synthezised events, or because you need to get backlight to be poll()/select() or inotify()-friendly if you don't want to add another dumbass userspace polling loop. Built-in headphone/speaker volume can be notified and controlled through an ALSA mixer. It won't be a nice poll-less thing, but I can trap the ACPI hot key events as a hint to update the mixer state, and if ALSA lets me do it, issue mixer changed notifications. And thinklight toggle key presses can be notified through the LED class, although that one is such an useless notification, that I simply don't know if I should bother with it. That covers all thinkpad "passive" EV_KEY events. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
