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Release 4.11 drivers/input/touchscreen/touchit213.c

/*
 * 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>


#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; }

Contributors

PersonTokensPropCommitsCommitProp
Claudio Nieder176100.00%1100.00%
Total176100.00%1100.00%

/* * 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); }

Contributors

PersonTokensPropCommitsCommitProp
Claudio Nieder59100.00%1100.00%
Total59100.00%1100.00%

/* * 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; }

Contributors

PersonTokensPropCommitsCommitProp
Claudio Nieder293100.00%1100.00%
Total293100.00%1100.00%

/* * 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, }; module_serio_driver(touchit213_drv);

Overall Contributors

PersonTokensPropCommitsCommitProp
Claudio Nieder72399.72%150.00%
Axel Lin20.28%150.00%
Total725100.00%2100.00%
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