Input: add driver for Tabletkiosk Sahara TouchIT-213 touchscreen

Signed-off-by: Claudio Nieder <private@claudio.ch>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/touchscreen/Kconfig

@@ -351,4 +351,15 @@ config TOUCHSCREEN_USB_GOTOP
 	bool "GoTop Super_Q2/GogoPen/PenPower tablet device support" if EMBEDDED
 	depends on TOUCHSCREEN_USB_COMPOSITE
 
+config TOUCHSCREEN_TOUCHIT213
+	tristate "Sahara TouchIT-213 touchscreen"
+	select SERIO
+	help
+	  Say Y here if you have a Sahara TouchIT-213 Tablet PC.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called touchit213.
+
 endif

drivers/input/touchscreen/Makefile

@@ -21,6 +21,7 @@ obj-$(CONFIG_TOUCHSCREEN_HP7XX)		+= jornada720_ts.o
 obj-$(CONFIG_TOUCHSCREEN_HTCPEN)	+= htcpen.o
 obj-$(CONFIG_TOUCHSCREEN_USB_COMPOSITE)	+= usbtouchscreen.o
 obj-$(CONFIG_TOUCHSCREEN_PENMOUNT)	+= penmount.o
+obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213)	+= touchit213.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT)	+= touchright.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN)	+= touchwin.o
 obj-$(CONFIG_TOUCHSCREEN_UCB1400)	+= ucb1400_ts.o

drivers/input/touchscreen/touchit213.c

@@ -0,0 +1,234 @@
+/*
+ * Sahara TouchIT-213 serial touchscreen driver
+ *
+ * Copyright (c) 2007-2008 Claudio Nieder <private@claudio.ch>
+ *
+ * Based on Touchright driver (drivers/input/touchscreen/touchright.c)
+ * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
+ * Copyright (c) 2004 Vojtech Pavlik
+ * and Dan Streetman <ddstreet@ieee.org>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/init.h>
+
+#define DRIVER_DESC	"Sahara TouchIT-213 serial touchscreen driver"
+
+MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Definitions & global arrays.
+ */
+
+/*
+ * Data is received through COM1 at 9600bit/s,8bit,no parity in packets
+ * of 5 byte each.
+ *
+ *   +--------+   +--------+   +--------+   +--------+   +--------+
+ *   |1000000p|   |0xxxxxxx|   |0xxxxxxx|   |0yyyyyyy|   |0yyyyyyy|
+ *   +--------+   +--------+   +--------+   +--------+   +--------+
+ *                    MSB          LSB          MSB          LSB
+ *
+ * The value of p is 1 as long as the screen is touched and 0 when
+ * reporting the location where touching stopped, e.g. where the pen was
+ * lifted from the screen.
+ *
+ * When holding the screen in landscape mode as the BIOS text output is
+ * presented, x is the horizontal axis with values growing from left to
+ * right and y is the vertical axis with values growing from top to
+ * bottom.
+ *
+ * When holding the screen in portrait mode with the Sahara logo in its
+ * correct position, x ist the vertical axis with values growing from
+ * top to bottom and y is the horizontal axis with values growing from
+ * right to left.
+ */
+
+#define T213_FORMAT_TOUCH_BIT	0x01
+#define T213_FORMAT_STATUS_BYTE	0x80
+#define T213_FORMAT_STATUS_MASK	~T213_FORMAT_TOUCH_BIT
+
+/*
+ * On my Sahara Touch-IT 213 I have observed x values from 0 to 0x7f0
+ * and y values from 0x1d to 0x7e9, so the actual measurement is
+ * probably done with an 11 bit precision.
+ */
+#define T213_MIN_XC 0
+#define T213_MAX_XC 0x07ff
+#define T213_MIN_YC 0
+#define T213_MAX_YC 0x07ff
+
+/*
+ * Per-touchscreen data.
+ */
+
+struct touchit213 {
+	struct input_dev *dev;
+	struct serio *serio;
+	int idx;
+	unsigned char csum;
+	unsigned char data[5];
+	char phys[32];
+};
+
+static irqreturn_t touchit213_interrupt(struct serio *serio,
+		unsigned char data, unsigned int flags)
+{
+	struct touchit213 *touchit213 = serio_get_drvdata(serio);
+	struct input_dev *dev = touchit213->dev;
+
+	touchit213->data[touchit213->idx] = data;
+
+	switch (touchit213->idx++) {
+	case 0:
+		if ((touchit213->data[0] & T213_FORMAT_STATUS_MASK) !=
+				T213_FORMAT_STATUS_BYTE) {
+			pr_debug("unsynchronized data: 0x%02x\n", data);
+			touchit213->idx = 0;
+		}
+		break;
+
+	case 4:
+		touchit213->idx = 0;
+		input_report_abs(dev, ABS_X,
+			(touchit213->data[1] << 7) | touchit213->data[2]);
+		input_report_abs(dev, ABS_Y,
+			(touchit213->data[3] << 7) | touchit213->data[4]);
+		input_report_key(dev, BTN_TOUCH,
+			touchit213->data[0] & T213_FORMAT_TOUCH_BIT);
+		input_sync(dev);
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * touchit213_disconnect() is the opposite of touchit213_connect()
+ */
+
+static void touchit213_disconnect(struct serio *serio)
+{
+	struct touchit213 *touchit213 = serio_get_drvdata(serio);
+
+	input_get_device(touchit213->dev);
+	input_unregister_device(touchit213->dev);
+	serio_close(serio);
+	serio_set_drvdata(serio, NULL);
+	input_put_device(touchit213->dev);
+	kfree(touchit213);
+}
+
+/*
+ * touchit213_connect() is the routine that is called when someone adds a
+ * new serio device that supports the Touchright protocol and registers it as
+ * an input device.
+ */
+
+static int touchit213_connect(struct serio *serio, struct serio_driver *drv)
+{
+	struct touchit213 *touchit213;
+	struct input_dev *input_dev;
+	int err;
+
+	touchit213 = kzalloc(sizeof(struct touchit213), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!touchit213 || !input_dev) {
+		err = -ENOMEM;
+		goto fail1;
+	}
+
+	touchit213->serio = serio;
+	touchit213->dev = input_dev;
+	snprintf(touchit213->phys, sizeof(touchit213->phys),
+		 "%s/input0", serio->phys);
+
+	input_dev->name = "Sahara Touch-iT213 Serial TouchScreen";
+	input_dev->phys = touchit213->phys;
+	input_dev->id.bustype = BUS_RS232;
+	input_dev->id.vendor = SERIO_TOUCHIT213;
+	input_dev->id.product = 0;
+	input_dev->id.version = 0x0100;
+	input_dev->dev.parent = &serio->dev;
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+	input_set_abs_params(touchit213->dev, ABS_X,
+			     T213_MIN_XC, T213_MAX_XC, 0, 0);
+	input_set_abs_params(touchit213->dev, ABS_Y,
+			     T213_MIN_YC, T213_MAX_YC, 0, 0);
+
+	serio_set_drvdata(serio, touchit213);
+
+	err = serio_open(serio, drv);
+	if (err)
+		goto fail2;
+
+	err = input_register_device(touchit213->dev);
+	if (err)
+		goto fail3;
+
+	return 0;
+
+ fail3:	serio_close(serio);
+ fail2:	serio_set_drvdata(serio, NULL);
+ fail1:	input_free_device(input_dev);
+	kfree(touchit213);
+	return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static struct serio_device_id touchit213_serio_ids[] = {
+	{
+		.type	= SERIO_RS232,
+		.proto	= SERIO_TOUCHIT213,
+		.id	= SERIO_ANY,
+		.extra	= SERIO_ANY,
+	},
+	{ 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, touchit213_serio_ids);
+
+static struct serio_driver touchit213_drv = {
+	.driver		= {
+		.name	= "touchit213",
+	},
+	.description	= DRIVER_DESC,
+	.id_table	= touchit213_serio_ids,
+	.interrupt	= touchit213_interrupt,
+	.connect	= touchit213_connect,
+	.disconnect	= touchit213_disconnect,
+};
+
+/*
+ * The functions for inserting/removing us as a module.
+ */
+
+static int __init touchit213_init(void)
+{
+	return serio_register_driver(&touchit213_drv);
+}
+
+static void __exit touchit213_exit(void)
+{
+	serio_unregister_driver(&touchit213_drv);
+}
+
+module_init(touchit213_init);
+module_exit(touchit213_exit);

include/linux/serio.h

@@ -213,5 +213,6 @@ static inline void serio_unpin_driver(struct serio *serio)
 #define SERIO_FUJITSU	0x35
 #define SERIO_ZHENHUA	0x36
 #define SERIO_INEXIO	0x37
+#define SERIO_TOUCHIT213	0x37
 
 #endif