[src/trunk]: src/sys/dev/pckbport synaptics: Automatically scroll when multip...

[nia <nia%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d4a5c3a13108
branches:  trunk
changeset: 745876:d4a5c3a13108
user:      nia <nia%NetBSD.org@localhost>
date:      Sat Mar 14 21:56:08 2020 +0000

description:
synaptics: Automatically scroll when multiple fingers are detected

This will mean we automatically get two-finger scrolling on multitouch
pads.

This works, but the scrolling is janky. Why does it eventually move the
mouse cursor (only one finger detected, but two are still there), and why
does it jump up slightly?

diffstat:

 sys/dev/pckbport/synaptics.c |  14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)

diffs (42 lines):

diff -r 8b1deda91eec -r d4a5c3a13108 sys/dev/pckbport/synaptics.c
--- a/sys/dev/pckbport/synaptics.c      Sat Mar 14 21:47:41 2020 +0000
+++ b/sys/dev/pckbport/synaptics.c      Sat Mar 14 21:56:08 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: synaptics.c,v 1.58 2020/03/14 21:23:32 nia Exp $       */
+/*     $NetBSD: synaptics.c,v 1.59 2020/03/14 21:56:08 nia Exp $       */
 
 /*
  * Copyright (c) 2005, Steve C. Woodford
@@ -48,7 +48,7 @@
 #include "opt_pms.h"
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: synaptics.c,v 1.58 2020/03/14 21:23:32 nia Exp $");
+__KERNEL_RCSID(0, "$NetBSD: synaptics.c,v 1.59 2020/03/14 21:56:08 nia Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -118,7 +118,7 @@
 static int synaptics_scale_z = 32;
 static int synaptics_max_speed_x = 32;
 static int synaptics_max_speed_y = 32;
-static int synaptics_max_speed_z = 2;
+static int synaptics_max_speed_z = 1;
 static int synaptics_movement_threshold = 4;
 static int synaptics_fscroll_min = 13;
 static int synaptics_fscroll_max = 14;
@@ -1745,6 +1745,14 @@
 
                        synaptics_movement(sc, sp, sp->sp_finger,
                                z_emul, &dx, &dy, &dz);
+               } else if (fingers > 1) {
+                       /*
+                        * Multiple finger movement. Interpret it as scrolling.
+                        */
+                       synaptics_movement(sc, sp, sp->sp_finger, 1,
+                               &dx, &dy, &dz);
+                       sc->rem_x[0] = sc->rem_y[0] = 0;
+                       dx = dy = 0;
                } else {
                        /*
                         * No valid finger. Therefore no movement.