2 * Elo 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 * This driver can handle serial Elo touchscreens using either the Elo standard
15 * 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo
16 * legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol.
19 #include <linux/errno.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/input.h>
24 #include <linux/serio.h>
25 #include <linux/init.h>
27 #define DRIVER_DESC "Elo serial touchscreen driver"
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30 MODULE_DESCRIPTION(DRIVER_DESC);
31 MODULE_LICENSE("GPL");
34 * Definitions & global arrays.
37 #define ELO_MAX_LENGTH 10
40 * Per-touchscreen data.
44 struct input_dev *dev;
49 unsigned char data[ELO_MAX_LENGTH];
53 static void elo_process_data_10(struct elo* elo, unsigned char data, struct pt_regs *regs)
55 struct input_dev *dev = elo->dev;
57 elo->csum += elo->data[elo->idx] = data;
77 input_regs(dev, regs);
78 input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
79 input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
80 input_report_abs(dev, ABS_PRESSURE, (elo->data[8] << 8) | elo->data[7]);
81 input_report_key(dev, BTN_TOUCH, elo->data[8] || elo->data[7]);
90 static void elo_process_data_6(struct elo* elo, unsigned char data, struct pt_regs *regs)
92 struct input_dev *dev = elo->dev;
94 elo->data[elo->idx] = data;
98 case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break;
99 case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break;
100 case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break;
108 input_regs(dev, regs);
109 input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
110 input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
113 input_report_key(dev, BTN_TOUCH, 1);
128 if ((data & 0xf0) == 0) {
129 input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
130 input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
138 static void elo_process_data_3(struct elo* elo, unsigned char data, struct pt_regs *regs)
140 struct input_dev *dev = elo->dev;
142 elo->data[elo->idx] = data;
144 switch (elo->idx++) {
147 if ((data & 0x7f) != 0x01)
151 input_regs(dev, regs);
152 input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
153 input_report_abs(dev, ABS_X, elo->data[1]);
154 input_report_abs(dev, ABS_Y, elo->data[2]);
161 static irqreturn_t elo_interrupt(struct serio *serio,
162 unsigned char data, unsigned int flags, struct pt_regs *regs)
164 struct elo* elo = serio_get_drvdata(serio);
168 elo_process_data_10(elo, data, regs);
173 elo_process_data_6(elo, data, regs);
177 elo_process_data_3(elo, data, regs);
185 * elo_disconnect() is the opposite of elo_connect()
188 static void elo_disconnect(struct serio *serio)
190 struct elo* elo = serio_get_drvdata(serio);
192 input_unregister_device(elo->dev);
194 serio_set_drvdata(serio, NULL);
199 * elo_connect() is the routine that is called when someone adds a
200 * new serio device that supports Gunze protocol and registers it as
204 static int elo_connect(struct serio *serio, struct serio_driver *drv)
207 struct input_dev *input_dev;
210 elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
211 input_dev = input_allocate_device();
212 if (!elo || !input_dev) {
218 elo->id = serio->id.id;
219 elo->dev = input_dev;
220 snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
222 input_dev->private = elo;
223 input_dev->name = "Elo Serial TouchScreen";
224 input_dev->phys = elo->phys;
225 input_dev->id.bustype = BUS_RS232;
226 input_dev->id.vendor = SERIO_ELO;
227 input_dev->id.product = elo->id;
228 input_dev->id.version = 0x0100;
229 input_dev->cdev.dev = &serio->dev;
231 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
232 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
236 case 0: /* 10-byte protocol */
237 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
238 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
239 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 255, 0, 0);
242 case 1: /* 6-byte protocol */
243 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
245 case 2: /* 4-byte protocol */
246 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
247 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
250 case 3: /* 3-byte protocol */
251 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
252 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
256 serio_set_drvdata(serio, elo);
258 err = serio_open(serio, drv);
262 input_register_device(elo->dev);
265 fail: serio_set_drvdata(serio, NULL);
266 input_free_device(input_dev);
272 * The serio driver structure.
275 static struct serio_device_id elo_serio_ids[] = {
285 MODULE_DEVICE_TABLE(serio, elo_serio_ids);
287 static struct serio_driver elo_drv = {
291 .description = DRIVER_DESC,
292 .id_table = elo_serio_ids,
293 .interrupt = elo_interrupt,
294 .connect = elo_connect,
295 .disconnect = elo_disconnect,
299 * The functions for inserting/removing us as a module.
302 static int __init elo_init(void)
304 serio_register_driver(&elo_drv);
308 static void __exit elo_exit(void)
310 serio_unregister_driver(&elo_drv);
313 module_init(elo_init);
314 module_exit(elo_exit);