[ 3.8.y.z extended stable ] Patch "Input: elantech - fix for newer hardware versions (v7)" 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 for newer hardware versions (v7)

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.7.

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

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 43a3beddef30b41e2c8e282d2308e9505ee8be3d Mon Sep 17 00:00:00 2001
From: Matteo Delfino <kendatsuba at gmail.com>
Date: Sat, 6 Jul 2013 21:52:26 -0700
Subject: Input: elantech - fix for newer hardware versions (v7)

commit 9eebed7de660c0b5ab129a9de4f89d20b60de68c upstream.

* Fix version recognition in elantech_set_properties

  The new hardware reports itself as v7 but the packets'
  structure is unaltered.

* Fix packet type recognition in elantech_packet_check_v4

  The bitmask used for v6 is too wide, only the last three bits of
  the third byte in a packet (packet[3] & 0x03) are actually used to
  distinguish between packet types.
  Starting from v7, additional information (to be interpreted) is
  stored in the remaining bits (packets[3] & 0x1c).
  In addition, the value stored in (packet[0] & 0x0c) is no longer
  a constant but contains additional information yet to be deciphered.
  This change should be backwards compatible with v6 hardware.

Additional-author: Giovanni Frigione <gio.frigione at gmail.com>
Signed-off-by: Matteo Delfino <kendatsuba at gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov at gmail.com>
Cc: Joseph Salisbury <joseph.salisbury at canonical.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/input/mouse/elantech.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 1e8e42f..57b2637 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -694,18 +694,18 @@ static int elantech_packet_check_v3(struct psmouse *psmouse)
 static int elantech_packet_check_v4(struct psmouse *psmouse)
 {
 	unsigned char *packet = psmouse->packet;
+	unsigned char packet_type = packet[3] & 0x03;

-	if ((packet[0] & 0x0c) == 0x04 &&
-	    (packet[3] & 0x1f) == 0x11)
+	switch (packet_type) {
+	case 0:
+		return PACKET_V4_STATUS;
+
+	case 1:
 		return PACKET_V4_HEAD;

-	if ((packet[0] & 0x0c) == 0x04 &&
-	    (packet[3] & 0x1f) == 0x12)
+	case 2:
 		return PACKET_V4_MOTION;
-
-	if ((packet[0] & 0x0c) == 0x04 &&
-	    (packet[3] & 0x1f) == 0x10)
-		return PACKET_V4_STATUS;
+	}

 	return PACKET_UNKNOWN;
 }
@@ -1282,6 +1282,7 @@ static int elantech_set_properties(struct elantech_data *etd)
 			etd->hw_version = 3;
 			break;
 		case 6:
+		case 7:
 			etd->hw_version = 4;
 			break;
 		default:
--
1.8.1.2