Input: add driver for Tabletkiosk Sahara TouchIT-213 touchscreen

	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

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

/*

 * 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);

#define SERIO_FUJITSU	0x35

#define SERIO_ZHENHUA	0x36

#define SERIO_INEXIO	0x37

#define SERIO_TOUCHIT213	0x37

#endif