On Tue, Jun 28, 2011 at 10:07 PM, <djkurtz@xxxxxxxxxxxx> wrote: > From: Daniel Kurtz <djkurtz@xxxxxxxxxxxx> > > Synaptics touchpads report a 'w' value in each data report. > For touchpads that support palm detection, when there is a single finger > on the pad, the 'w' value reports its width in the range 4 to 15. > Thus, the minimum valid width is 4. > > Note: Other values of 'w' are used to report special conditions: > w=0: 2 fingers are on the pad > w=1: 3 or more fingers are on the pad > w=2: the packet contains "Advanced Gesture Mode" data. Ideally we should scale this to a physically meaningful quantity instead, such as surface units. That would require knowing the distance between each capacitive touch channel and then scaling W - 4 by that amount before reporting it. These values are all kind of mysterious to user-space anyways unless the physical nature of the device is known by other means (such as configuration files). Jeff. -- 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
