2 * Fujitsu serial touchscreen driver
4 * Copyright (c) Dmitry Torokhov <dtor@mail.ru>
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
10 * by the Free Software Foundation.
13 #include <linux/errno.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/input.h>
18 #include <linux/serio.h>
19 #include <linux/init.h>
21 #define DRIVER_DESC "Fujitsu serial touchscreen driver"
23 MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
24 MODULE_DESCRIPTION(DRIVER_DESC);
25 MODULE_LICENSE("GPL");
27 #define FUJITSU_LENGTH 5
30 * Per-touchscreen data.
33 struct input_dev *dev;
36 unsigned char data[FUJITSU_LENGTH];
41 * Decode serial data (5 bytes per packet)
44 * Where C is 1 while in calibration mode (which we don't use)
45 * R is 1 when no coordinate corection was done.
48 static irqreturn_t fujitsu_interrupt(struct serio *serio,
49 unsigned char data, unsigned int flags)
51 struct fujitsu *fujitsu = serio_get_drvdata(serio);
52 struct input_dev *dev = fujitsu->dev;
54 if (fujitsu->idx == 0) {
55 /* resync skip until start of frame */
56 if ((data & 0xf0) != 0x80)
59 /* resync skip garbage */
66 fujitsu->data[fujitsu->idx++] = data;
67 if (fujitsu->idx == FUJITSU_LENGTH) {
68 input_report_abs(dev, ABS_X,
69 (fujitsu->data[2] << 7) | fujitsu->data[1]);
70 input_report_abs(dev, ABS_Y,
71 (fujitsu->data[4] << 7) | fujitsu->data[3]);
72 input_report_key(dev, BTN_TOUCH,
73 (fujitsu->data[0] & 0x03) != 2);
82 * fujitsu_disconnect() is the opposite of fujitsu_connect()
84 static void fujitsu_disconnect(struct serio *serio)
86 struct fujitsu *fujitsu = serio_get_drvdata(serio);
88 input_get_device(fujitsu->dev);
89 input_unregister_device(fujitsu->dev);
91 serio_set_drvdata(serio, NULL);
92 input_put_device(fujitsu->dev);
97 * fujitsu_connect() is the routine that is called when someone adds a
98 * new serio device that supports the Fujitsu protocol and registers it
101 static int fujitsu_connect(struct serio *serio, struct serio_driver *drv)
103 struct fujitsu *fujitsu;
104 struct input_dev *input_dev;
107 fujitsu = kzalloc(sizeof(struct fujitsu), GFP_KERNEL);
108 input_dev = input_allocate_device();
109 if (!fujitsu || !input_dev) {
114 fujitsu->serio = serio;
115 fujitsu->dev = input_dev;
116 snprintf(fujitsu->phys, sizeof(fujitsu->phys),
117 "%s/input0", serio->phys);
119 input_dev->name = "Fujitsu Serial Touchscreen";
120 input_dev->phys = fujitsu->phys;
121 input_dev->id.bustype = BUS_RS232;
122 input_dev->id.vendor = SERIO_FUJITSU;
123 input_dev->id.product = 0;
124 input_dev->id.version = 0x0100;
125 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
126 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
128 input_set_abs_params(input_dev, ABS_X, 0, 4096, 0, 0);
129 input_set_abs_params(input_dev, ABS_Y, 0, 4096, 0, 0);
130 serio_set_drvdata(serio, fujitsu);
132 err = serio_open(serio, drv);
136 err = input_register_device(fujitsu->dev);
145 serio_set_drvdata(serio, NULL);
147 input_free_device(input_dev);
153 * The serio driver structure.
155 static struct serio_device_id fujitsu_serio_ids[] = {
158 .proto = SERIO_FUJITSU,
165 MODULE_DEVICE_TABLE(serio, fujitsu_serio_ids);
167 static struct serio_driver fujitsu_drv = {
169 .name = "fujitsu_ts",
171 .description = DRIVER_DESC,
172 .id_table = fujitsu_serio_ids,
173 .interrupt = fujitsu_interrupt,
174 .connect = fujitsu_connect,
175 .disconnect = fujitsu_disconnect,
178 static int __init fujitsu_init(void)
180 return serio_register_driver(&fujitsu_drv);
183 static void __exit fujitsu_exit(void)
185 serio_unregister_driver(&fujitsu_drv);
188 module_init(fujitsu_init);
189 module_exit(fujitsu_exit);