2 * MicroTouch (3M) serial touchscreen driver
4 * Copyright (c) 2004 Vojtech Pavlik
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published by
10 * the Free Software Foundation.
14 * 2005/02/19 Dan Streetman <ddstreet@ieee.org>
15 * Copied elo.c and edited for MicroTouch protocol
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 #include <linux/input.h>
23 #include <linux/serio.h>
24 #include <linux/init.h>
26 #define DRIVER_DESC "MicroTouch serial touchscreen driver"
28 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
29 MODULE_DESCRIPTION(DRIVER_DESC
);
30 MODULE_LICENSE("GPL");
33 * Definitions & global arrays.
36 #define MTOUCH_FORMAT_TABLET_STATUS_BIT 0x80
37 #define MTOUCH_FORMAT_TABLET_TOUCH_BIT 0x40
38 #define MTOUCH_FORMAT_TABLET_LENGTH 5
39 #define MTOUCH_RESPONSE_BEGIN_BYTE 0x01
40 #define MTOUCH_RESPONSE_END_BYTE 0x0d
42 /* todo: check specs for max length of all responses */
43 #define MTOUCH_MAX_LENGTH 16
45 #define MTOUCH_MIN_XC 0
46 #define MTOUCH_MAX_XC 0x3fff
47 #define MTOUCH_MIN_YC 0
48 #define MTOUCH_MAX_YC 0x3fff
50 #define MTOUCH_GET_XC(data) (((data[2])<<7) | data[1])
51 #define MTOUCH_GET_YC(data) (((data[4])<<7) | data[3])
52 #define MTOUCH_GET_TOUCHED(data) (MTOUCH_FORMAT_TABLET_TOUCH_BIT & data[0])
55 * Per-touchscreen data.
59 struct input_dev
*dev
;
62 unsigned char data
[MTOUCH_MAX_LENGTH
];
66 static void mtouch_process_format_tablet(struct mtouch
*mtouch
)
68 struct input_dev
*dev
= mtouch
->dev
;
70 if (MTOUCH_FORMAT_TABLET_LENGTH
== ++mtouch
->idx
) {
71 input_report_abs(dev
, ABS_X
, MTOUCH_GET_XC(mtouch
->data
));
72 input_report_abs(dev
, ABS_Y
, MTOUCH_MAX_YC
- MTOUCH_GET_YC(mtouch
->data
));
73 input_report_key(dev
, BTN_TOUCH
, MTOUCH_GET_TOUCHED(mtouch
->data
));
80 static void mtouch_process_response(struct mtouch
*mtouch
)
82 if (MTOUCH_RESPONSE_END_BYTE
== mtouch
->data
[mtouch
->idx
++]) {
83 /* FIXME - process response */
85 } else if (MTOUCH_MAX_LENGTH
== mtouch
->idx
) {
86 printk(KERN_ERR
"mtouch.c: too many response bytes\n");
91 static irqreturn_t
mtouch_interrupt(struct serio
*serio
,
92 unsigned char data
, unsigned int flags
)
94 struct mtouch
* mtouch
= serio_get_drvdata(serio
);
96 mtouch
->data
[mtouch
->idx
] = data
;
98 if (MTOUCH_FORMAT_TABLET_STATUS_BIT
& mtouch
->data
[0])
99 mtouch_process_format_tablet(mtouch
);
100 else if (MTOUCH_RESPONSE_BEGIN_BYTE
== mtouch
->data
[0])
101 mtouch_process_response(mtouch
);
103 printk(KERN_DEBUG
"mtouch.c: unknown/unsynchronized data from device, byte %x\n",mtouch
->data
[0]);
109 * mtouch_disconnect() is the opposite of mtouch_connect()
112 static void mtouch_disconnect(struct serio
*serio
)
114 struct mtouch
* mtouch
= serio_get_drvdata(serio
);
116 input_get_device(mtouch
->dev
);
117 input_unregister_device(mtouch
->dev
);
119 serio_set_drvdata(serio
, NULL
);
120 input_put_device(mtouch
->dev
);
125 * mtouch_connect() is the routine that is called when someone adds a
126 * new serio device that supports MicroTouch (Format Tablet) protocol and registers it as
130 static int mtouch_connect(struct serio
*serio
, struct serio_driver
*drv
)
132 struct mtouch
*mtouch
;
133 struct input_dev
*input_dev
;
136 mtouch
= kzalloc(sizeof(struct mtouch
), GFP_KERNEL
);
137 input_dev
= input_allocate_device();
138 if (!mtouch
|| !input_dev
) {
143 mtouch
->serio
= serio
;
144 mtouch
->dev
= input_dev
;
145 snprintf(mtouch
->phys
, sizeof(mtouch
->phys
), "%s/input0", serio
->phys
);
147 input_dev
->private = mtouch
;
148 input_dev
->name
= "MicroTouch Serial TouchScreen";
149 input_dev
->phys
= mtouch
->phys
;
150 input_dev
->id
.bustype
= BUS_RS232
;
151 input_dev
->id
.vendor
= SERIO_MICROTOUCH
;
152 input_dev
->id
.product
= 0;
153 input_dev
->id
.version
= 0x0100;
154 input_dev
->evbit
[0] = BIT(EV_KEY
) | BIT(EV_ABS
);
155 input_dev
->keybit
[LONG(BTN_TOUCH
)] = BIT(BTN_TOUCH
);
156 input_set_abs_params(mtouch
->dev
, ABS_X
, MTOUCH_MIN_XC
, MTOUCH_MAX_XC
, 0, 0);
157 input_set_abs_params(mtouch
->dev
, ABS_Y
, MTOUCH_MIN_YC
, MTOUCH_MAX_YC
, 0, 0);
159 serio_set_drvdata(serio
, mtouch
);
161 err
= serio_open(serio
, drv
);
165 input_register_device(mtouch
->dev
);
169 fail
: serio_set_drvdata(serio
, NULL
);
170 input_free_device(input_dev
);
176 * The serio driver structure.
179 static struct serio_device_id mtouch_serio_ids
[] = {
182 .proto
= SERIO_MICROTOUCH
,
189 MODULE_DEVICE_TABLE(serio
, mtouch_serio_ids
);
191 static struct serio_driver mtouch_drv
= {
195 .description
= DRIVER_DESC
,
196 .id_table
= mtouch_serio_ids
,
197 .interrupt
= mtouch_interrupt
,
198 .connect
= mtouch_connect
,
199 .disconnect
= mtouch_disconnect
,
203 * The functions for inserting/removing us as a module.
206 static int __init
mtouch_init(void)
208 serio_register_driver(&mtouch_drv
);
212 static void __exit
mtouch_exit(void)
214 serio_unregister_driver(&mtouch_drv
);
217 module_init(mtouch_init
);
218 module_exit(mtouch_exit
);