1 /*
2  * $Id: gunze.c,v 1.12 2001/09/25 10:12:07 vojtech Exp $
3  *
4  *  Copyright (c) 2000-2001 Vojtech Pavlik
5  */
6 
7 /*
8  * Gunze AHL-51S touchscreen driver for Linux
9  */
10 
11 /*
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25  *
26  * Should you need to contact me, the author, you can do so either by
27  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
28  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
29  */
30 
31 #include <linux/errno.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/slab.h>
35 #include <linux/input.h>
36 #include <linux/serio.h>
37 #include <linux/init.h>
38 
39 #define DRIVER_DESC	"Gunze AHL-51S touchscreen driver"
40 
41 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
42 MODULE_DESCRIPTION(DRIVER_DESC);
43 MODULE_LICENSE("GPL");
44 
45 /*
46  * Definitions & global arrays.
47  */
48 
49 #define	GUNZE_MAX_LENGTH	10
50 
51 /*
52  * Per-touchscreen data.
53  */
54 
55 struct gunze {
56 	struct input_dev *dev;
57 	struct serio *serio;
58 	int idx;
59 	unsigned char data[GUNZE_MAX_LENGTH];
60 	char phys[32];
61 };
62 
63 static void gunze_process_packet(struct gunze* gunze, struct pt_regs *regs)
64 {
65 	struct input_dev *dev = gunze->dev;
66 
67 	if (gunze->idx != GUNZE_MAX_LENGTH || gunze->data[5] != ',' ||
68 		(gunze->data[0] != 'T' && gunze->data[0] != 'R')) {
69 		printk(KERN_WARNING "gunze.c: bad packet: >%.*s<\n", GUNZE_MAX_LENGTH, gunze->data);
70 		return;
71 	}
72 
73 	input_regs(dev, regs);
74 	input_report_abs(dev, ABS_X, simple_strtoul(gunze->data + 1, NULL, 10));
75 	input_report_abs(dev, ABS_Y, 1024 - simple_strtoul(gunze->data + 6, NULL, 10));
76 	input_report_key(dev, BTN_TOUCH, gunze->data[0] == 'T');
77 	input_sync(dev);
78 }
79 
80 static irqreturn_t gunze_interrupt(struct serio *serio,
81 		unsigned char data, unsigned int flags, struct pt_regs *regs)
82 {
83 	struct gunze* gunze = serio_get_drvdata(serio);
84 
85 	if (data == '\r') {
86 		gunze_process_packet(gunze, regs);
87 		gunze->idx = 0;
88 	} else {
89 		if (gunze->idx < GUNZE_MAX_LENGTH)
90 			gunze->data[gunze->idx++] = data;
91 	}
92 	return IRQ_HANDLED;
93 }
94 
95 /*
96  * gunze_disconnect() is the opposite of gunze_connect()
97  */
98 
99 static void gunze_disconnect(struct serio *serio)
100 {
101 	struct gunze *gunze = serio_get_drvdata(serio);
102 
103 	input_get_device(gunze->dev);
104 	input_unregister_device(gunze->dev);
105 	serio_close(serio);
106 	serio_set_drvdata(serio, NULL);
107 	input_put_device(gunze->dev);
108 	kfree(gunze);
109 }
110 
111 /*
112  * gunze_connect() is the routine that is called when someone adds a
113  * new serio device that supports Gunze protocol and registers it as
114  * an input device.
115  */
116 
117 static int gunze_connect(struct serio *serio, struct serio_driver *drv)
118 {
119 	struct gunze *gunze;
120 	struct input_dev *input_dev;
121 	int err;
122 
123 	gunze = kzalloc(sizeof(struct gunze), GFP_KERNEL);
124 	input_dev = input_allocate_device();
125 	if (!gunze || !input_dev) {
126 		err = -ENOMEM;
127 		goto fail;
128 	}
129 
130 	gunze->serio = serio;
131 	gunze->dev = input_dev;
132 	sprintf(gunze->phys, "%s/input0", serio->phys);
133 
134 	input_dev->private = gunze;
135 	input_dev->name = "Gunze AHL-51S TouchScreen";
136 	input_dev->phys = gunze->phys;
137 	input_dev->id.bustype = BUS_RS232;
138 	input_dev->id.vendor = SERIO_GUNZE;
139 	input_dev->id.product = 0x0051;
140 	input_dev->id.version = 0x0100;
141 	input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
142 	input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
143 	input_set_abs_params(input_dev, ABS_X, 24, 1000, 0, 0);
144 	input_set_abs_params(input_dev, ABS_Y, 24, 1000, 0, 0);
145 
146 	serio_set_drvdata(serio, gunze);
147 
148 	err = serio_open(serio, drv);
149 	if (err)
150 		goto fail;
151 
152 	input_register_device(gunze->dev);
153 	return 0;
154 
155  fail:	serio_set_drvdata(serio, NULL);
156 	input_free_device(input_dev);
157 	kfree(gunze);
158 	return err;
159 }
160 
161 /*
162  * The serio driver structure.
163  */
164 
165 static struct serio_device_id gunze_serio_ids[] = {
166 	{
167 		.type	= SERIO_RS232,
168 		.proto	= SERIO_GUNZE,
169 		.id	= SERIO_ANY,
170 		.extra	= SERIO_ANY,
171 	},
172 	{ 0 }
173 };
174 
175 MODULE_DEVICE_TABLE(serio, gunze_serio_ids);
176 
177 static struct serio_driver gunze_drv = {
178 	.driver		= {
179 		.name	= "gunze",
180 	},
181 	.description	= DRIVER_DESC,
182 	.id_table	= gunze_serio_ids,
183 	.interrupt	= gunze_interrupt,
184 	.connect	= gunze_connect,
185 	.disconnect	= gunze_disconnect,
186 };
187 
188 /*
189  * The functions for inserting/removing us as a module.
190  */
191 
192 static int __init gunze_init(void)
193 {
194 	serio_register_driver(&gunze_drv);
195 	return 0;
196 }
197 
198 static void __exit gunze_exit(void)
199 {
200 	serio_unregister_driver(&gunze_drv);
201 }
202 
203 module_init(gunze_init);
204 module_exit(gunze_exit);
205