summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/fujitsu_ts.c
blob: daf7a4afc9352e08afe3e04637a18bd8698382eb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
/*
 * Fujitsu serial touchscreen driver
 *
 * Copyright (c) Dmitry Torokhov <dtor@mail.ru>
 */

/*
 * 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	"Fujitsu serial touchscreen driver"

MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

#define FUJITSU_LENGTH 5

/*
 * Per-touchscreen data.
 */
struct fujitsu {
	struct input_dev *dev;
	struct serio *serio;
	int idx;
	unsigned char data[FUJITSU_LENGTH];
	char phys[32];
};

/*
 * Decode serial data (5 bytes per packet)
 * First byte
 * 1 C 0 0 R S S S
 * Where C is 1 while in calibration mode (which we don't use)
 * R is 1 when no coordinate corection was done.
 * S are button state
 */
static irqreturn_t fujitsu_interrupt(struct serio *serio,
				     unsigned char data, unsigned int flags)
{
	struct fujitsu *fujitsu = serio_get_drvdata(serio);
	struct input_dev *dev = fujitsu->dev;

	if (fujitsu->idx == 0) {
		/* resync skip until start of frame */
		if ((data & 0xf0) != 0x80)
			return IRQ_HANDLED;
	} else {
		/* resync skip garbage */
		if (data & 0x80) {
			fujitsu->idx = 0;
			return IRQ_HANDLED;
		}
	}

	fujitsu->data[fujitsu->idx++] = data;
	if (fujitsu->idx == FUJITSU_LENGTH) {
		input_report_abs(dev, ABS_X,
				 (fujitsu->data[2] << 7) | fujitsu->data[1]);
		input_report_abs(dev, ABS_Y,
				 (fujitsu->data[4] << 7) | fujitsu->data[3]);
		input_report_key(dev, BTN_TOUCH,
				 (fujitsu->data[0] & 0x03) != 2);
		input_sync(dev);
		fujitsu->idx = 0;
	}

	return IRQ_HANDLED;
}

/*
 * fujitsu_disconnect() is the opposite of fujitsu_connect()
 */
static void fujitsu_disconnect(struct serio *serio)
{
	struct fujitsu *fujitsu = serio_get_drvdata(serio);

	input_get_device(fujitsu->dev);
	input_unregister_device(fujitsu->dev);
	serio_close(serio);
	serio_set_drvdata(serio, NULL);
	input_put_device(fujitsu->dev);
	kfree(fujitsu);
}

/*
 * fujitsu_connect() is the routine that is called when someone adds a
 * new serio device that supports the Fujitsu protocol and registers it
 * as input device.
 */
static int fujitsu_connect(struct serio *serio, struct serio_driver *drv)
{
	struct fujitsu *fujitsu;
	struct input_dev *input_dev;
	int err;

	fujitsu = kzalloc(sizeof(struct fujitsu), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!fujitsu || !input_dev) {
		err = -ENOMEM;
		goto fail1;
	}

	fujitsu->serio = serio;
	fujitsu->dev = input_dev;
	snprintf(fujitsu->phys, sizeof(fujitsu->phys),
		 "%s/input0", serio->phys);

	input_dev->name = "Fujitsu Serial Touchscreen";
	input_dev->phys = fujitsu->phys;
	input_dev->id.bustype = BUS_RS232;
	input_dev->id.vendor = SERIO_FUJITSU;
	input_dev->id.product = 0;
	input_dev->id.version = 0x0100;
	input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
	input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);

	input_set_abs_params(input_dev, ABS_X, 0, 4096, 0, 0);
	input_set_abs_params(input_dev, ABS_Y, 0, 4096, 0, 0);
	serio_set_drvdata(serio, fujitsu);

	err = serio_open(serio, drv);
	if (err)
		goto fail2;

	err = input_register_device(fujitsu->dev);
	if (err)
		goto fail3;

	return 0;

 fail3:
	serio_close(serio);
 fail2:
	serio_set_drvdata(serio, NULL);
 fail1:
	input_free_device(input_dev);
	kfree(fujitsu);
	return err;
}

/*
 * The serio driver structure.
 */
static struct serio_device_id fujitsu_serio_ids[] = {
	{
		.type	= SERIO_RS232,
		.proto	= SERIO_FUJITSU,
		.id	= SERIO_ANY,
		.extra	= SERIO_ANY,
	},
	{ 0 }
};

MODULE_DEVICE_TABLE(serio, fujitsu_serio_ids);

static struct serio_driver fujitsu_drv = {
	.driver		= {
		.name	= "fujitsu_ts",
	},
	.description	= DRIVER_DESC,
	.id_table	= fujitsu_serio_ids,
	.interrupt	= fujitsu_interrupt,
	.connect	= fujitsu_connect,
	.disconnect	= fujitsu_disconnect,
};

static int __init fujitsu_init(void)
{
	return serio_register_driver(&fujitsu_drv);
}

static void __exit fujitsu_exit(void)
{
	serio_unregister_driver(&fujitsu_drv);
}

module_init(fujitsu_init);
module_exit(fujitsu_exit);
OpenPOWER on IntegriCloud