Patch "Input: elantech - mark protocols v2 and v3 as semi-mt" has been added to the 3.14-stable tree

Patch "Input: elantech - mark protocols v2 and v3 as semi-mt" has been added to the 3.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    Input: elantech - mark protocols v2 and v3 as semi-mt

to the 3.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     input-elantech-mark-protocols-v2-and-v3-as-semi-mt.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 6544a1df11c48c8413071aac3316792e4678fbfb Mon Sep 17 00:00:00 2001
From: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Date: Mon, 11 Jan 2016 17:35:38 -0800
Subject: Input: elantech - mark protocols v2 and v3 as semi-mt

From: Benjamin Tissoires <benjamin.tissoires@redhat.com>

commit 6544a1df11c48c8413071aac3316792e4678fbfb upstream.

When using a protocol v2 or v3 hardware, elantech uses the function
elantech_report_semi_mt_data() to report data. This devices are rather
creepy because if num_finger is 3, (x2,y2) is (0,0). Yes, only one valid
touch is reported.

Anyway, userspace (libinput) is now confused by these (0,0) touches,
and detect them as palm, and rejects them.

Commit 3c0213d17a09 ("Input: elantech - fix semi-mt protocol for v3 HW")
was sufficient enough for xf86-input-synaptics and libinput before it has
palm rejection. Now we need to actually tell libinput that this device is
a semi-mt one and it should not rely on the actual values of the 2 touches.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/input/mouse/elantech.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -1111,7 +1111,7 @@ static int elantech_set_input_params(str
 			input_set_abs_params(dev, ABS_TOOL_WIDTH, ETP_WMIN_V2,
 					     ETP_WMAX_V2, 0, 0);
 		}
-		input_mt_init_slots(dev, 2, 0);
+		input_mt_init_slots(dev, 2, INPUT_MT_SEMI_MT);
 		input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
 		input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
 		break;


Patches currently in stable-queue which might be from benjamin.tissoires@redhat.com are

queue-3.14/input-elantech-mark-protocols-v2-and-v3-as-semi-mt.patch