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
19 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
20 MODULE_DESCRIPTION(DRIVER_DESC);
21 MODULE_LICENSE("GPL");
22
23 /*
24 * Definitions & global arrays.
25 */
26
27 #define GUNZE_MAX_LENGTH 10
28
29 /*
30 * Per-touchscreen data.
31 */
32
33 struct 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
gunze_process_packet(struct gunze * gunze)41 static 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, simple_strtoul(gunze->data + 1, NULL, 10));
52 input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10));
53 input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T');
54 input_sync(dev);
55 }
56
gunze_interrupt(struct serio * serio,unsigned char data,unsigned int flags)57 static 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
gunze_disconnect(struct serio * serio)76 static void gunze_disconnect(struct serio *serio)
77 {
78 struct gunze *gunze = serio_get_drvdata(serio);
79
80 input_get_device(gunze->dev);
81 input_unregister_device(gunze->dev);
82 serio_close(serio);
83 serio_set_drvdata(serio, NULL);
84 input_put_device(gunze->dev);
85 kfree(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
gunze_connect(struct serio * serio,struct serio_driver * drv)94 static 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(sizeof(*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(gunze->phys, sizeof(serio->phys), "%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(input_dev, ABS_X, 24, 1000, 0, 0);
121 input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0);
122
123 serio_set_drvdata(serio, 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(input_dev);
138 kfree(gunze);
139 return err;
140 }
141
142 /*
143 * The serio driver structure.
144 */
145
146 static 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
156 MODULE_DEVICE_TABLE(serio, gunze_serio_ids);
157
158 static 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
169 module_serio_driver(gunze_drv);
170