1/*
2 * Touchright serial touchscreen driver
3 *
4 * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
5 *
6 * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c)
7 * Copyright (c) 2004 Vojtech Pavlik
8 * and Dan Streetman <ddstreet@ieee.org>
9 */
10
11/*
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License version 2 as published
14 * by the Free Software Foundation.
15 */
16
17#include <linux/errno.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/slab.h>
21#include <linux/input.h>
22#include <linux/serio.h>
23
24#define DRIVER_DESC	"Touchright serial touchscreen driver"
25
26MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
27MODULE_DESCRIPTION(DRIVER_DESC);
28MODULE_LICENSE("GPL");
29
30/*
31 * Definitions & global arrays.
32 */
33
34#define TR_FORMAT_TOUCH_BIT	0x01
35#define TR_FORMAT_STATUS_BYTE	0x40
36#define TR_FORMAT_STATUS_MASK	~TR_FORMAT_TOUCH_BIT
37
38#define TR_LENGTH 5
39
40#define TR_MIN_XC 0
41#define TR_MAX_XC 0x1ff
42#define TR_MIN_YC 0
43#define TR_MAX_YC 0x1ff
44
45/*
46 * Per-touchscreen data.
47 */
48
49struct tr {
50	struct input_dev *dev;
51	struct serio *serio;
52	int idx;
53	unsigned char data[TR_LENGTH];
54	char phys[32];
55};
56
57static irqreturn_t tr_interrupt(struct serio *serio,
58		unsigned char data, unsigned int flags)
59{
60	struct tr *tr = serio_get_drvdata(serio);
61	struct input_dev *dev = tr->dev;
62
63	tr->data[tr->idx] = data;
64
65	if ((tr->data[0] & TR_FORMAT_STATUS_MASK) == TR_FORMAT_STATUS_BYTE) {
66		if (++tr->idx == TR_LENGTH) {
67			input_report_abs(dev, ABS_X,
68				(tr->data[1] << 5) | (tr->data[2] >> 1));
69			input_report_abs(dev, ABS_Y,
70				(tr->data[3] << 5) | (tr->data[4] >> 1));
71			input_report_key(dev, BTN_TOUCH,
72				tr->data[0] & TR_FORMAT_TOUCH_BIT);
73			input_sync(dev);
74			tr->idx = 0;
75		}
76	}
77
78	return IRQ_HANDLED;
79}
80
81/*
82 * tr_disconnect() is the opposite of tr_connect()
83 */
84
85static void tr_disconnect(struct serio *serio)
86{
87	struct tr *tr = serio_get_drvdata(serio);
88
89	input_get_device(tr->dev);
90	input_unregister_device(tr->dev);
91	serio_close(serio);
92	serio_set_drvdata(serio, NULL);
93	input_put_device(tr->dev);
94	kfree(tr);
95}
96
97/*
98 * tr_connect() is the routine that is called when someone adds a
99 * new serio device that supports the Touchright protocol and registers it as
100 * an input device.
101 */
102
103static int tr_connect(struct serio *serio, struct serio_driver *drv)
104{
105	struct tr *tr;
106	struct input_dev *input_dev;
107	int err;
108
109	tr = kzalloc(sizeof(struct tr), GFP_KERNEL);
110	input_dev = input_allocate_device();
111	if (!tr || !input_dev) {
112		err = -ENOMEM;
113		goto fail1;
114	}
115
116	tr->serio = serio;
117	tr->dev = input_dev;
118	snprintf(tr->phys, sizeof(tr->phys), "%s/input0", serio->phys);
119
120	input_dev->name = "Touchright Serial TouchScreen";
121	input_dev->phys = tr->phys;
122	input_dev->id.bustype = BUS_RS232;
123	input_dev->id.vendor = SERIO_TOUCHRIGHT;
124	input_dev->id.product = 0;
125	input_dev->id.version = 0x0100;
126	input_dev->dev.parent = &serio->dev;
127	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
128	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
129	input_set_abs_params(tr->dev, ABS_X, TR_MIN_XC, TR_MAX_XC, 0, 0);
130	input_set_abs_params(tr->dev, ABS_Y, TR_MIN_YC, TR_MAX_YC, 0, 0);
131
132	serio_set_drvdata(serio, tr);
133
134	err = serio_open(serio, drv);
135	if (err)
136		goto fail2;
137
138	err = input_register_device(tr->dev);
139	if (err)
140		goto fail3;
141
142	return 0;
143
144 fail3:	serio_close(serio);
145 fail2:	serio_set_drvdata(serio, NULL);
146 fail1:	input_free_device(input_dev);
147	kfree(tr);
148	return err;
149}
150
151/*
152 * The serio driver structure.
153 */
154
155static struct serio_device_id tr_serio_ids[] = {
156	{
157		.type	= SERIO_RS232,
158		.proto	= SERIO_TOUCHRIGHT,
159		.id	= SERIO_ANY,
160		.extra	= SERIO_ANY,
161	},
162	{ 0 }
163};
164
165MODULE_DEVICE_TABLE(serio, tr_serio_ids);
166
167static struct serio_driver tr_drv = {
168	.driver		= {
169		.name	= "touchright",
170	},
171	.description	= DRIVER_DESC,
172	.id_table	= tr_serio_ids,
173	.interrupt	= tr_interrupt,
174	.connect	= tr_connect,
175	.disconnect	= tr_disconnect,
176};
177
178module_serio_driver(tr_drv);
179