Hi Mark, On 4/16/24 1:57 AM, Mark Pearson wrote: > Hi Dmitry, > > On Mon, Apr 15, 2024, at 6:54 PM, Dmitry Torokhov wrote: >> On Mon, Apr 15, 2024 at 04:28:19PM -0400, Mark Pearson wrote: >>> Hi >>> >>> On Mon, Apr 15, 2024, at 3:58 PM, Dmitry Torokhov wrote: >>>> On Mon, Apr 15, 2024 at 09:50:37PM +0200, Hans de Goede wrote: >>>>> Hi, >>>>> >>>>> On 4/15/24 9:40 PM, Dmitry Torokhov wrote: >>>>>> On Wed, Apr 10, 2024 at 10:48:10PM -0400, Mark Pearson wrote: >>>>>>> >>>>>>> I have a stronger preference to keep the KEY_DOUBLECLICK - that one seems less controversial as a genuine new input event. >>>>>> >>>>>> Please see my response to Peter's letter. I think it very much depends >>>>>> on how it will be used (associated with the pointer or standalone as it >>>>>> is now). >>>>>> >>>>>> For standalone application, recalling your statement that on Win you >>>>>> have this gesture invoke configuration utility I would argue for >>>>>> KEY_CONFIG for it. >>>>> >>>>> KEY_CONFIG is already generated by Fn + F# on some ThinkPads to launch >>>>> the GNOME/KDE control center/panel and I believe that at least GNOME >>>>> comes with a default binding to map KEY_CONFIG to the control-center. >>>> >>>> Not KEY_CONTROLPANEL? >>>> >>>> Are there devices that use both Fn+# and the doubleclick? Would it be an >>>> acceptable behavior for the users to have them behave the same? >>>> >>> Catching up with the thread, thanks for all the comments. >>> >>> For FN+N (originally KEY_DEBUG_SYS_INFO) the proposal was to now use >>> KEY_VENDOR there. My conclusion was that this is targeting vendor >>> specific functionality, and that was the closest fit, if a new keycode >>> was not preferred. >> >> Fn+N -> KEY_VENDOR mapping sounds good to me. >> >>> >>> For the doubletap (which is a unique input event - not related to the >>> pointer) I would like to keep it as a new unique event. >>> >>> I think it's most likely use would be for control panel, but I don't >>> think it should be limited to that. I can see it being useful if users >>> are able to reconfigure it to launch something different (browser or >>> music player maybe?), hence it would be best if it did not conflict >>> with an existing keycode function. I also can't confirm it doesn't >>> clash on existing or future systems - it's possible. >> >> So here is the problem. Keycodes in linux input are not mere >> placeholders for something that will be decided later how it is to be >> used, they are supposed to communicate intent and userspace ideally does >> not need to have any additional knowledge about where the event is >> coming from. A keyboard either internal or external sends KEY_SCREENLOCK >> and the system should lock the screen. It should not be aware that one >> device was a generic USB external keyboard while another had an internal >> sensor that recognized hovering palm making swiping motion to the right >> because a vendor decided to make it. Otherwise you have millions of >> input devices all generating unique codes and you need userspace to >> decide how to interpret data coming from each device individually. >> >> If you truly do not have a defined use case for it you have a couple >> options: >> >> - assign it KEY_RESERVED, ensure your driver allows remapping to an >> arbitrary keycode, let user or distro assign desired keycode to it >> >> - assign KEY_PROG1 .. KEY_PROG4 - pretty much the same - leave it in the >> hand of the user to define a shortcut in their DE to make it useful >> >>> >>> FWIW - I wouldn't be surprised with some of the new gaming systems >>> we're seeing (Steamdeck, Legion-Go, etc), that a doubletap event on a >>> joystick might be useful to have, if the HW supports it? >> >> What would it do exactly? Once we have this answer we can define key or >> button code (although I do agree that game controller buttons are >> different from "normal" keys because they map to the geometry of the >> controller which in turn defines their commonly understood function). >> >> But in any case you would not reuse the same keycode for something that >> is supposed to invoke a configuration utility and also to let's say >> drop a flash grenade in a game. >> > > Understood. > > I don't see a path forward within your stated parameters. I did not realise that there were such limitations, so my apologies for wasting everybody's time, and thank you for your patience and guidance. > > I will drop this patch from the series and proceed using existing defined codes only. > > Hans, I'll need to rejig things a bits but I have some ideas and I think I can make it work and stay within the pdx86 tree, which will make it simpler. Ok this sounds good to me. For Fn + N using KEY_VENDOR sounds good for me and for the doubletap any one of KEY_CONFIG/KEY_CONTROLPANEL/KEY_INFO/KEY_PROG1 or some other suitable KEY_foo define works for me. Regards, Hans