[ 3.5.y.z extended stable ] Patch "Input: elantech - fix for newer hardware versions (v7)" has been added to staging queue

[Luis Henriques]

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-3.5.y-queue branch of the 3.5.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-3.5.y-queue

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

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 32304556261ed2ed3dc31bffb60b399321571182 Mon Sep 17 00:00:00 2001
From: Matteo Delfino <kendatsuba at gmail.com>
Date: Sat, 6 Jul 2013 21:52:26 -0700
Subject: [PATCH] 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: Luis Henriques <luis.henriques 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 4790110..9e47774 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:
--
1.8.3.2