Hello all, I'm currently working with a touchpad vendor with a new device that supports a limited form of hover detection. Their sensor is able to detect the presence or absence of a finger/hand/palm hovering over the sensor without touching it, but is unable to report any more details about it. This is a more limited form of hover detection than some devices which attach a hover state to each finger they see, and can even report x/y coordinates to hovering finger. Instead of using ABS_MT_DISTANCE, it appears that the correct event to use would be ABS_DISTANCE, since the value is not tied to a specific finger. I would like to check with you all about how this value is intended to be used, because it's not quite as obvious to me as I first thought. We need to handle three basic states: 1. At least one finger is touching the pad. 2. Something is hovering, but nothing is actually touching. 3. Nothing is touching the pad and nothing is detected hovering over it either It's seems clear to me that an ABS_DISTANCE of zero should indicate state #1 and that any other legal positive value should indicate state #2, but I'm less clear on what the best way to handle state #3 is. Currently, I think the best strategy would be to use a value of ABS_DISTANCE = -1 to indicate that there are no fingers seen (hovering or otherwise), does that make sense? If not this, how else would you suggest that this ought to be done? Thank you, Charlie -- 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
