Hi Daniel, > Synaptics image sensor touchpads track 5 fingers, but only report 2. > This patch attempts to deal with some idiosyncrasies of these > touchpads: I appreciate the complexity of the protocol at hand, and the patch is doing an excellent job documenting it. However, it does constitute a fair deal of code... What about the statements below: 1. When two subsequent sgm packets report the same number of fingers (and unless told otherwise in some other fashion?), the sgm and the previous agm contains data for the same fingers as the previous (agm, sgm) pair, i.e., there is no transition. 2. There is no general way to know which fingers are being reported after a transition. If both points above are true, how about something like this: a) Always report slots zero and one (for two or more fingers) b) Keep a global number, trackid c) Parse are buffer agm d) Parse sgm e) If a transition occured, increase trackid by two f) Set TRACKING_ID to trackid in slot zero and trackid+1 in slot one. It seems to me the above will result in contiuous handling of two unknown contacts in between transitions, and during transitions, new contacts will be generated. The algorithm above could possibly be improved for the 2->1 transition, but from what I gather, 1->2 and 2->3 as well as 3->2 does not seem to be generally solvable, hence resulting in the above anyways. If any of points 1 and 2 are wrong, I am sure you will enlighten/remind me. ;-) Cheers, 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
