[3.19.y-ckt stable] Patch "Input: elantech - fix semi-mt protocol for v3 HW" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    Input: elantech - fix semi-mt protocol for v3 HW

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt2.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 85f1d315c7bb079a89772a03ee76c7973e2c4a5b Mon Sep 17 00:00:00 2001
From: Benjamin Tissoires <benjamin.tissoires at redhat.com>
Date: Thu, 23 Apr 2015 09:08:43 -0700
Subject: Input: elantech - fix semi-mt protocol for v3 HW

commit 3c0213d17a09601e0c6c0ae0e27caf70d988290f upstream.

When the v3 hardware sees more than one finger, it uses the semi-mt
protocol to report the touches. However, it currently works when
num_fingers is 0, 1 or 2, but when it is 3 and above, it sends only 1
finger as if num_fingers was 1.

This confuses userspace which knows how to deal with extra fingers
when all the slots are used, but not when some are missing.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=90101

Signed-off-by: Benjamin Tissoires <benjamin.tissoires at redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/input/mouse/elantech.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 991dc6b..79363b6 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -315,7 +315,7 @@ static void elantech_report_semi_mt_data(struct input_dev *dev,
 					 unsigned int x2, unsigned int y2)
 {
 	elantech_set_slot(dev, 0, num_fingers != 0, x1, y1);
-	elantech_set_slot(dev, 1, num_fingers == 2, x2, y2);
+	elantech_set_slot(dev, 1, num_fingers >= 2, x2, y2);
 }

 /*
--
1.9.1