From dd24bbe4bbffc5e711edd4ff81bd0fff668525a2 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Fri, 11 Apr 2014 20:41:36 +0200
Subject: [PATCH synaptics] Always count tripletap + click as 3 fingerclick on
 pads with < 3 touches

When trying to do a 3 fingerclick on a touchpad which only tracks 2 touches,
this may register as a 3 or 2 fingerclick depending on the order in which
the touchpad detects the fingers. If the 2 outer fingers of the 3 get seen
first, then the 2 touches will be too far apart for the heuristic to see
them as being close together, and the click gets counted as a 2 finger click.

A user will likely never do a 2 finger click with a 3th finger resting
somewhere else on the pad, where-as the above misdetection of the clicks is
a real issue, so simply always count a click with trippletap set as a
3 finger click on pads which track less then 3 touches.

https://bugzilla.redhat.com/show_bug.cgi?id=1086218

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
(cherry picked from commit a6f0f4c9a5bcb0e25343dd4c59d4cc47cc5e8006)
---
 src/synaptics.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/synaptics.c b/src/synaptics.c
index 68705e7..f5f3251 100644
--- a/src/synaptics.c
+++ b/src/synaptics.c
@@ -2591,6 +2591,13 @@ clickpad_guess_clickfingers(SynapticsPrivate * priv,
         close_point >>= 1;
     }
 
+    /* Some trackpads touchpad only track two touchpoints but announce
+     * BTN_TOOL_TRIPLETAP (which sets hw->numFingers to 3), when this happens
+     * the user likely intents to do a 3 finger click, so handle it as such.
+     */
+    if (hw->numFingers >= 3 && hw->num_mt_mask < 3)
+        nfingers = 3;
+
     return nfingers;
 }
 
-- 
1.9.3