1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2000-2001 Vojtech Pavlik
4 */
5
6/*
7 * Gunze AHL-51S touchscreen driver for Linux
8 */
9
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/input.h>
15#include <linux/serio.h>
16
17#define DRIVER_DESC "Gunze AHL-51S touchscreen driver"
18
19MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
20MODULE_DESCRIPTION(DRIVER_DESC);
21MODULE_LICENSE("GPL");
22
23/*
24 * Definitions & global arrays.
25 */
26
27#define GUNZE_MAX_LENGTH 10
28
29/*
30 * Per-touchscreen data.
31 */
32
33struct gunze {
34 struct input_dev *dev;
35 struct serio *serio;
36 int idx;
37 unsigned char data[GUNZE_MAX_LENGTH];
38 char phys[32];
39};
40
41static void gunze_process_packet(struct gunze *gunze)
42{
43 struct input_dev *dev = gunze->dev;
44
45 if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' ||
46 (gunze->data[0] != 'T' && gunze->data[0] != 'R')) {
47 printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data);
48 return;
49 }
50
51 input_report_abs(dev, ABS_X, value: simple_strtoul(gunze->data + 1, NULL, 10));
52 input_report_abs(dev, ABS_Y, value: 1024 - simple_strtoul(gunze->data + 6, NULL, 10));
53 input_report_key(dev, BTN_TOUCH, value: gunze->data[0] == 'T');
54 input_sync(dev);
55}
56
57static irqreturn_t gunze_interrupt(struct serio *serio,
58 unsigned char data, unsigned int flags)
59{
60 struct gunze *gunze = serio_get_drvdata(serio);
61
62 if (data == '\r') {
63 gunze_process_packet(gunze);
64 gunze->idx = 0;
65 } else {
66 if (gunze->idx < GUNZE_MAX_LENGTH)
67 gunze->data[gunze->idx++] = data;
68 }
69 return IRQ_HANDLED;
70}
71
72/*
73 * gunze_disconnect() is the opposite of gunze_connect()
74 */
75
76static void gunze_disconnect(struct serio *serio)
77{
78 struct gunze *gunze = serio_get_drvdata(serio);
79
80 input_get_device(dev: gunze->dev);
81 input_unregister_device(gunze->dev);
82 serio_close(serio);
83 serio_set_drvdata(serio, NULL);
84 input_put_device(dev: gunze->dev);
85 kfree(objp: gunze);
86}
87
88/*
89 * gunze_connect() is the routine that is called when someone adds a
90 * new serio device that supports Gunze protocol and registers it as
91 * an input device.
92 */
93
94static int gunze_connect(struct serio *serio, struct serio_driver *drv)
95{
96 struct gunze *gunze;
97 struct input_dev *input_dev;
98 int err;
99
100 gunze = kzalloc(size: sizeof(struct gunze), GFP_KERNEL);
101 input_dev = input_allocate_device();
102 if (!gunze || !input_dev) {
103 err = -ENOMEM;
104 goto fail1;
105 }
106
107 gunze->serio = serio;
108 gunze->dev = input_dev;
109 snprintf(buf: gunze->phys, size: sizeof(serio->phys), fmt: "%s/input0", serio->phys);
110
111 input_dev->name = "Gunze AHL-51S TouchScreen";
112 input_dev->phys = gunze->phys;
113 input_dev->id.bustype = BUS_RS232;
114 input_dev->id.vendor = SERIO_GUNZE;
115 input_dev->id.product = 0x0051;
116 input_dev->id.version = 0x0100;
117 input_dev->dev.parent = &serio->dev;
118 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
119 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
120 input_set_abs_params(dev: input_dev, ABS_X, min: 24, max: 1000, fuzz: 0, flat: 0);
121 input_set_abs_params(dev: input_dev, ABS_Y, min: 24, max: 1000, fuzz: 0, flat: 0);
122
123 serio_set_drvdata(serio, data: gunze);
124
125 err = serio_open(serio, drv);
126 if (err)
127 goto fail2;
128
129 err = input_register_device(gunze->dev);
130 if (err)
131 goto fail3;
132
133 return 0;
134
135 fail3: serio_close(serio);
136 fail2: serio_set_drvdata(serio, NULL);
137 fail1: input_free_device(dev: input_dev);
138 kfree(objp: gunze);
139 return err;
140}
141
142/*
143 * The serio driver structure.
144 */
145
146static const struct serio_device_id gunze_serio_ids[] = {
147 {
148 .type = SERIO_RS232,
149 .proto = SERIO_GUNZE,
150 .id = SERIO_ANY,
151 .extra = SERIO_ANY,
152 },
153 { 0 }
154};
155
156MODULE_DEVICE_TABLE(serio, gunze_serio_ids);
157
158static struct serio_driver gunze_drv = {
159 .driver = {
160 .name = "gunze",
161 },
162 .description = DRIVER_DESC,
163 .id_table = gunze_serio_ids,
164 .interrupt = gunze_interrupt,
165 .connect = gunze_connect,
166 .disconnect = gunze_disconnect,
167};
168
169module_serio_driver(gunze_drv);
170

source code of linux/drivers/input/touchscreen/gunze.c