tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Touchwindow 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/*
18 * 2005/02/19 Rick Koch:
19 * The Touchwindow I used is made by Edmark Corp. and
20 * constantly outputs a stream of 0's unless it is touched.
21 * It then outputs 3 bytes: X, Y, and a copy of Y.
22 */
23
24#include <linux/errno.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/input.h>
29#include <linux/serio.h>
30#include <linux/init.h>
31
32#define DRIVER_DESC "Touchwindow serial touchscreen driver"
33
34MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
35MODULE_DESCRIPTION(DRIVER_DESC);
36MODULE_LICENSE("GPL");
37
38/*
39 * Definitions & global arrays.
40 */
41
42#define TW_LENGTH 3
43
44#define TW_MIN_XC 0
45#define TW_MAX_XC 0xff
46#define TW_MIN_YC 0
47#define TW_MAX_YC 0xff
48
49/*
50 * Per-touchscreen data.
51 */
52
53struct tw {
54 struct input_dev *dev;
55 struct serio *serio;
56 int idx;
57 int touched;
58 unsigned char data[TW_LENGTH];
59 char phys[32];
60};
61
62static irqreturn_t tw_interrupt(struct serio *serio,
63 unsigned char data, unsigned int flags, struct pt_regs *regs)
64{
65 struct tw *tw = serio_get_drvdata(serio);
66 struct input_dev *dev = tw->dev;
67
68 if (data) { /* touch */
69 tw->touched = 1;
70 tw->data[tw->idx++] = data;
71 /* verify length and that the two Y's are the same */
72 if (tw->idx == TW_LENGTH && tw->data[1] == tw->data[2]) {
73 input_regs(dev, regs);
74 input_report_abs(dev, ABS_X, tw->data[0]);
75 input_report_abs(dev, ABS_Y, tw->data[1]);
76 input_report_key(dev, BTN_TOUCH, 1);
77 input_sync(dev);
78 tw->idx = 0;
79 }
80 } else if (tw->touched) { /* untouch */
81 input_report_key(dev, BTN_TOUCH, 0);
82 input_sync(dev);
83 tw->idx = 0;
84 tw->touched = 0;
85 }
86
87 return IRQ_HANDLED;
88}
89
90/*
91 * tw_disconnect() is the opposite of tw_connect()
92 */
93
94static void tw_disconnect(struct serio *serio)
95{
96 struct tw *tw = serio_get_drvdata(serio);
97
98 input_get_device(tw->dev);
99 input_unregister_device(tw->dev);
100 serio_close(serio);
101 serio_set_drvdata(serio, NULL);
102 input_put_device(tw->dev);
103 kfree(tw);
104}
105
106/*
107 * tw_connect() is the routine that is called when someone adds a
108 * new serio device that supports the Touchwin protocol and registers it as
109 * an input device.
110 */
111
112static int tw_connect(struct serio *serio, struct serio_driver *drv)
113{
114 struct tw *tw;
115 struct input_dev *input_dev;
116 int err;
117
118 tw = kzalloc(sizeof(struct tw), GFP_KERNEL);
119 input_dev = input_allocate_device();
120 if (!tw || !input_dev) {
121 err = -ENOMEM;
122 goto fail1;
123 }
124
125 tw->serio = serio;
126 tw->dev = input_dev;
127 snprintf(tw->phys, sizeof(tw->phys), "%s/input0", serio->phys);
128
129 input_dev->private = tw;
130 input_dev->name = "Touchwindow Serial TouchScreen";
131 input_dev->phys = tw->phys;
132 input_dev->id.bustype = BUS_RS232;
133 input_dev->id.vendor = SERIO_TOUCHWIN;
134 input_dev->id.product = 0;
135 input_dev->id.version = 0x0100;
136 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
137 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
138 input_set_abs_params(tw->dev, ABS_X, TW_MIN_XC, TW_MAX_XC, 0, 0);
139 input_set_abs_params(tw->dev, ABS_Y, TW_MIN_YC, TW_MAX_YC, 0, 0);
140
141 serio_set_drvdata(serio, tw);
142
143 err = serio_open(serio, drv);
144 if (err)
145 goto fail2;
146
147 err = input_register_device(tw->dev);
148 if (err)
149 goto fail3;
150
151 return 0;
152
153 fail3: serio_close(serio);
154 fail2: serio_set_drvdata(serio, NULL);
155 fail1: input_free_device(input_dev);
156 kfree(tw);
157 return err;
158}
159
160/*
161 * The serio driver structure.
162 */
163
164static struct serio_device_id tw_serio_ids[] = {
165 {
166 .type = SERIO_RS232,
167 .proto = SERIO_TOUCHWIN,
168 .id = SERIO_ANY,
169 .extra = SERIO_ANY,
170 },
171 { 0 }
172};
173
174MODULE_DEVICE_TABLE(serio, tw_serio_ids);
175
176static struct serio_driver tw_drv = {
177 .driver = {
178 .name = "touchwin",
179 },
180 .description = DRIVER_DESC,
181 .id_table = tw_serio_ids,
182 .interrupt = tw_interrupt,
183 .connect = tw_connect,
184 .disconnect = tw_disconnect,
185};
186
187/*
188 * The functions for inserting/removing us as a module.
189 */
190
191static int __init tw_init(void)
192{
193 serio_register_driver(&tw_drv);
194 return 0;
195}
196
197static void __exit tw_exit(void)
198{
199 serio_unregister_driver(&tw_drv);
200}
201
202module_init(tw_init);
203module_exit(tw_exit);