1/*
2 * Penmount serial touchscreen driver
3 *
4 * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
5 *
6 * Based on ELO driver (drivers/input/touchscreen/elo.c)
7 * Copyright (c) 2004 Vojtech Pavlik
8 */
9
10/*
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 as published
13 * by the Free Software Foundation.
14 */
15
16#include <linux/errno.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/input.h>
21#include <linux/serio.h>
22#include <linux/init.h>
23
24#define DRIVER_DESC	"Penmount serial touchscreen driver"
25
26MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
27MODULE_DESCRIPTION(DRIVER_DESC);
28MODULE_LICENSE("GPL");
29
30/*
31 * Definitions & global arrays.
32 */
33
34#define	PM_MAX_LENGTH	5
35
36/*
37 * Per-touchscreen data.
38 */
39
40struct pm {
41	struct input_dev *dev;
42	struct serio *serio;
43	int idx;
44	unsigned char data[PM_MAX_LENGTH];
45	char phys[32];
46};
47
48static irqreturn_t pm_interrupt(struct serio *serio,
49		unsigned char data, unsigned int flags)
50{
51	struct pm *pm = serio_get_drvdata(serio);
52	struct input_dev *dev = pm->dev;
53
54	pm->data[pm->idx] = data;
55
56	if (pm->data[0] & 0x80) {
57		if (PM_MAX_LENGTH == ++pm->idx) {
58			input_report_abs(dev, ABS_X, pm->data[2] * 128 + pm->data[1]);
59			input_report_abs(dev, ABS_Y, pm->data[4] * 128 + pm->data[3]);
60			input_report_key(dev, BTN_TOUCH, !!(pm->data[0] & 0x40));
61			input_sync(dev);
62			pm->idx = 0;
63		}
64	}
65
66	return IRQ_HANDLED;
67}
68
69/*
70 * pm_disconnect() is the opposite of pm_connect()
71 */
72
73static void pm_disconnect(struct serio *serio)
74{
75	struct pm *pm = serio_get_drvdata(serio);
76
77	input_get_device(pm->dev);
78	input_unregister_device(pm->dev);
79	serio_close(serio);
80	serio_set_drvdata(serio, NULL);
81	input_put_device(pm->dev);
82	kfree(pm);
83}
84
85/*
86 * pm_connect() is the routine that is called when someone adds a
87 * new serio device that supports Gunze protocol and registers it as
88 * an input device.
89 */
90
91static int pm_connect(struct serio *serio, struct serio_driver *drv)
92{
93	struct pm *pm;
94	struct input_dev *input_dev;
95	int err;
96
97	pm = kzalloc(sizeof(struct pm), GFP_KERNEL);
98	input_dev = input_allocate_device();
99	if (!pm || !input_dev) {
100		err = -ENOMEM;
101		goto fail1;
102	}
103
104	pm->serio = serio;
105	pm->dev = input_dev;
106	snprintf(pm->phys, sizeof(pm->phys), "%s/input0", serio->phys);
107
108	input_dev->name = "Penmount Serial TouchScreen";
109	input_dev->phys = pm->phys;
110	input_dev->id.bustype = BUS_RS232;
111	input_dev->id.vendor = SERIO_PENMOUNT;
112	input_dev->id.product = 0;
113	input_dev->id.version = 0x0100;
114	input_dev->dev.parent = &serio->dev;
115
116        input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
117        input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
118        input_set_abs_params(pm->dev, ABS_X, 0, 0x3ff, 0, 0);
119        input_set_abs_params(pm->dev, ABS_Y, 0, 0x3ff, 0, 0);
120
121	serio_set_drvdata(serio, pm);
122
123	err = serio_open(serio, drv);
124	if (err)
125		goto fail2;
126
127	err = input_register_device(pm->dev);
128	if (err)
129		goto fail3;
130
131	return 0;
132
133 fail3:	serio_close(serio);
134 fail2:	serio_set_drvdata(serio, NULL);
135 fail1:	input_free_device(input_dev);
136	kfree(pm);
137	return err;
138}
139
140/*
141 * The serio driver structure.
142 */
143
144static struct serio_device_id pm_serio_ids[] = {
145	{
146		.type	= SERIO_RS232,
147		.proto	= SERIO_PENMOUNT,
148		.id	= SERIO_ANY,
149		.extra	= SERIO_ANY,
150	},
151	{ 0 }
152};
153
154MODULE_DEVICE_TABLE(serio, pm_serio_ids);
155
156static struct serio_driver pm_drv = {
157	.driver		= {
158		.name	= "penmountlpc",
159	},
160	.description	= DRIVER_DESC,
161	.id_table	= pm_serio_ids,
162	.interrupt	= pm_interrupt,
163	.connect	= pm_connect,
164	.disconnect	= pm_disconnect,
165};
166
167/*
168 * The functions for inserting/removing us as a module.
169 */
170
171static int __init pm_init(void)
172{
173	return serio_register_driver(&pm_drv);
174}
175
176static void __exit pm_exit(void)
177{
178	serio_unregister_driver(&pm_drv);
179}
180
181module_init(pm_init);
182module_exit(pm_exit);
183