Hi Chis, > Extra clarification on whats going on here: > > Patch #1 removes BTN_TOOL_TRIPLETAP; among other supporting 2 finger > touch code. In that context, it was used as an awkward indication to > xf86-input-wacom that device supported 2 finger touch. Which is great, no argument there. > In this patch #3, it removes BTN_TOOL_DOUBLETAP; which was an awkward > indication to xf86-input-wacom that device supports 1 finger touch. > Once this patch is applied, applications must deduce touchscreen input > supports 1 finger touch same way as they do for other touchscreens > (not seeing BTN_TOOL_FINGER and no stylus related BTN_'s as well). Also makes sense - I only noticed that it was gone without replacement, and Ping's and your answer gives ample rationale for its removal. > Patch #4 adds BTN_TOOL_DOUBLETAP back but using normal meaning that > the device supports 2 finger touch. Right, thanks. > I had reviewed this patch series in context of some related changes > from Ping to xf86-input-wacom. I wanted to document doubletap part of > that review on this list though. > > Ping originally didn't want to add that back in. At least one of the > reasons was that there were no known applications that supported both > "touchscreens" (absolute mode) and the BTN_TOOL_DOUBLETAP at same > time. Given the current state of userland, a touchscreen should not emit doubletaps, true. > I did look around quite a bit after Ping's comment and I couldn't come > up with anything (mtdev, xf86-input-evdev, etc). So its a good point. > When something supports ABS_MT_*, thats given much more weight then > BTN_TOOL_DOUPLETAP would; which is the case here. Yes - unless the device is of the SEMI_MT kind, the finger-counting BTN_TOOL_* events really have no meaning. > Anyways, I requested if Ping would add BTN_TOOL_DOUBLETAP in to align > with current hid-ntrig and since it didn't seem to hurt and could > possibly help some future app. Please double check me here if it is > in fact a good idea to add DOUBLETAP in for touchscreens. In fact, I think it hurts a bit, so removing it is a good idea. Thanks, Henrik -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
