File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/input/mouse/touchkit_ps2.c b/drivers/input/mouse/touchkit_ps2.c
new file mode 100644
index 0000000..1fd8f5e
--- /dev/null
+++ b/drivers/input/mouse/touchkit_ps2.c
@@ -0,0 +1,100 @@
+/* ----------------------------------------------------------------------------
+ * touchkit_ps2.c  --  Driver for eGalax TouchKit PS/2 Touchscreens
+ *
+ * Copyright (C) 2005 by Stefan Lucke
+ * Copyright (C) 2004 by Daniel Ritz
+ * Copyright (C) by Todd E. Johnson (mtouchusb.c)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Based upon touchkitusb.c
+ *
+ * Vendor documentation is available at:
+ * http://home.eeti.com.tw/web20/drivers/Software%20Programming%20Guide_v2.0.pdf 
+ */
+
+#include <linux/kernel.h>
+
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/libps2.h>
+
+#include "psmouse.h"
+#include "touchkit_ps2.h"
+
+#define TOUCHKIT_MAX_XC			0x07ff
+#define TOUCHKIT_MAX_YC			0x07ff
+
+#define TOUCHKIT_CMD			0x0a
+#define TOUCHKIT_CMD_LENGTH		1
+
+#define TOUCHKIT_CMD_ACTIVE		'A'
+#define TOUCHKIT_CMD_FIRMWARE_VERSION	'D'
+#define TOUCHKIT_CMD_CONTROLLER_TYPE	'E'
+
+#define TOUCHKIT_SEND_PARMS(s, r, c)	((s) << 12 | (r) << 8 | (c))
+
+#define TOUCHKIT_GET_TOUCHED(packet)	(((packet)[0]) & 0x01)
+#define TOUCHKIT_GET_X(packet)		(((packet)[1] << 7) | (packet)[2])
+#define TOUCHKIT_GET_Y(packet)		(((packet)[3] << 7) | (packet)[4])
+
+static psmouse_ret_t touchkit_ps2_process_byte(struct psmouse *psmouse)
+{
+	unsigned char *packet = psmouse->packet;
+	struct input_dev *dev = psmouse->dev;
+
+	if (psmouse->pktcnt != 5)
+		return PSMOUSE_GOOD_DATA;
+
+	input_report_abs(dev, ABS_X, TOUCHKIT_GET_X(packet));
+	input_report_abs(dev, ABS_Y, TOUCHKIT_GET_Y(packet));
+	input_report_key(dev, BTN_TOUCH, TOUCHKIT_GET_TOUCHED(packet));
+	input_sync(dev);
+
+	return PSMOUSE_FULL_PACKET;
+}
+
+int touchkit_ps2_detect(struct psmouse *psmouse, bool set_properties)
+{
+	struct input_dev *dev = psmouse->dev;
+	unsigned char param[3];
+	int command;
+
+	param[0] = TOUCHKIT_CMD_LENGTH;
+	param[1] = TOUCHKIT_CMD_ACTIVE;
+	command = TOUCHKIT_SEND_PARMS(2, 3, TOUCHKIT_CMD);
+
+	if (ps2_command(&psmouse->ps2dev, param, command))
+		return -ENODEV;
+
+	if (param[0] != TOUCHKIT_CMD || param[1] != 0x01 ||
+	    param[2] != TOUCHKIT_CMD_ACTIVE)
+		return -ENODEV;
+
+	if (set_properties) {
+		dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+		dev->keybit[BIT_WORD(BTN_MOUSE)] = 0;
+		dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+		input_set_abs_params(dev, ABS_X, 0, TOUCHKIT_MAX_XC, 0, 0);
+		input_set_abs_params(dev, ABS_Y, 0, TOUCHKIT_MAX_YC, 0, 0);
+
+		psmouse->vendor = "eGalax";
+		psmouse->name = "Touchscreen";
+		psmouse->protocol_handler = touchkit_ps2_process_byte;
+		psmouse->pktsize = 5;
+	}
+
+	return 0;
+}