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>
26 #include <linux/ctype.h>
28 #define DRIVER_DESC "Elo serial touchscreen driver"
30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
31 MODULE_DESCRIPTION(DRIVER_DESC);
32 MODULE_LICENSE("GPL");
35 * Definitions & global arrays.
38 #define ELO_MAX_LENGTH 10
40 #define ELO10_PACKET_LEN 8
41 #define ELO10_TOUCH 0x03
42 #define ELO10_PRESSURE 0x80
44 #define ELO10_LEAD_BYTE 'U'
46 #define ELO10_ID_CMD 'i'
48 #define ELO10_TOUCH_PACKET 'T'
49 #define ELO10_ACK_PACKET 'A'
50 #define ELI10_ID_PACKET 'I'
53 * Per-touchscreen data.
57 struct input_dev *dev;
59 struct mutex cmd_mutex;
60 struct completion cmd_done;
63 unsigned char expected_packet;
65 unsigned char data[ELO_MAX_LENGTH];
66 unsigned char response[ELO10_PACKET_LEN];
70 static void elo_process_data_10(struct elo *elo, unsigned char data, struct pt_regs *regs)
72 struct input_dev *dev = elo->dev;
74 elo->data[elo->idx] = data;
78 if (data != ELO10_LEAD_BYTE) {
79 pr_debug("elo: unsynchronized data: 0x%02x\n", data);
86 if (data != elo->csum) {
87 pr_debug("elo: bad checksum: 0x%02x, expected 0x%02x\n",
91 if (elo->data[1] != elo->expected_packet) {
92 if (elo->data[1] != ELO10_TOUCH_PACKET)
93 pr_debug("elo: unexpected packet: 0x%02x\n",
97 if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) {
98 input_regs(dev, regs);
99 input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
100 input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
101 if (elo->data[2] & ELO10_PRESSURE)
102 input_report_abs(dev, ABS_PRESSURE,
103 (elo->data[8] << 8) | elo->data[7]);
104 input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
106 } else if (elo->data[1] == ELO10_ACK_PACKET) {
107 if (elo->data[2] == '0')
108 elo->expected_packet = ELO10_TOUCH_PACKET;
109 complete(&elo->cmd_done);
111 memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
112 elo->expected_packet = ELO10_ACK_PACKET;
119 static void elo_process_data_6(struct elo *elo, unsigned char data, struct pt_regs *regs)
121 struct input_dev *dev = elo->dev;
123 elo->data[elo->idx] = data;
125 switch (elo->idx++) {
127 case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break;
128 case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break;
129 case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break;
137 input_regs(dev, regs);
138 input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
139 input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
142 input_report_key(dev, BTN_TOUCH, 1);
157 if ((data & 0xf0) == 0) {
158 input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
159 input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
167 static void elo_process_data_3(struct elo *elo, unsigned char data, struct pt_regs *regs)
169 struct input_dev *dev = elo->dev;
171 elo->data[elo->idx] = data;
173 switch (elo->idx++) {
176 if ((data & 0x7f) != 0x01)
180 input_regs(dev, regs);
181 input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
182 input_report_abs(dev, ABS_X, elo->data[1]);
183 input_report_abs(dev, ABS_Y, elo->data[2]);
190 static irqreturn_t elo_interrupt(struct serio *serio,
191 unsigned char data, unsigned int flags, struct pt_regs *regs)
193 struct elo *elo = serio_get_drvdata(serio);
197 elo_process_data_10(elo, data, regs);
202 elo_process_data_6(elo, data, regs);
206 elo_process_data_3(elo, data, regs);
213 static int elo_command_10(struct elo *elo, unsigned char *packet)
217 unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
219 mutex_lock(&elo->cmd_mutex);
221 serio_pause_rx(elo->serio);
222 elo->expected_packet = toupper(packet[0]);
223 init_completion(&elo->cmd_done);
224 serio_continue_rx(elo->serio);
226 if (serio_write(elo->serio, ELO10_LEAD_BYTE))
229 for (i = 0; i < ELO10_PACKET_LEN; i++) {
231 if (serio_write(elo->serio, packet[i]))
235 if (serio_write(elo->serio, csum))
238 wait_for_completion_timeout(&elo->cmd_done, HZ);
240 if (elo->expected_packet == ELO10_TOUCH_PACKET) {
241 /* We are back in reporting mode, the command was ACKed */
242 memcpy(packet, elo->response, ELO10_PACKET_LEN);
247 mutex_unlock(&elo->cmd_mutex);
251 static int elo_setup_10(struct elo *elo)
253 static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
254 struct input_dev *dev = elo->dev;
255 unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
257 if (elo_command_10(elo, packet))
260 dev->id.version = (packet[5] << 8) | packet[4];
262 input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
263 input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
264 if (packet[3] & ELO10_PRESSURE)
265 input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
267 printk(KERN_INFO "elo: %sTouch touchscreen, fw: %02x.%02x, "
268 "features: %x02x, controller: 0x%02x\n",
269 elo_types[(packet[1] -'0') & 0x03],
270 packet[5], packet[4], packet[3], packet[7]);
276 * elo_disconnect() is the opposite of elo_connect()
279 static void elo_disconnect(struct serio *serio)
281 struct elo *elo = serio_get_drvdata(serio);
283 input_get_device(elo->dev);
284 input_unregister_device(elo->dev);
286 serio_set_drvdata(serio, NULL);
287 input_put_device(elo->dev);
292 * elo_connect() is the routine that is called when someone adds a
293 * new serio device that supports Gunze protocol and registers it as
297 static int elo_connect(struct serio *serio, struct serio_driver *drv)
300 struct input_dev *input_dev;
303 elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
304 input_dev = input_allocate_device();
305 if (!elo || !input_dev) {
311 elo->id = serio->id.id;
312 elo->dev = input_dev;
313 elo->expected_packet = ELO10_TOUCH_PACKET;
314 mutex_init(&elo->cmd_mutex);
315 init_completion(&elo->cmd_done);
316 snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
318 input_dev->private = elo;
319 input_dev->name = "Elo Serial TouchScreen";
320 input_dev->phys = elo->phys;
321 input_dev->id.bustype = BUS_RS232;
322 input_dev->id.vendor = SERIO_ELO;
323 input_dev->id.product = elo->id;
324 input_dev->id.version = 0x0100;
325 input_dev->cdev.dev = &serio->dev;
327 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
328 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
330 serio_set_drvdata(serio, elo);
331 err = serio_open(serio, drv);
337 case 0: /* 10-byte protocol */
338 if (elo_setup_10(elo))
343 case 1: /* 6-byte protocol */
344 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
346 case 2: /* 4-byte protocol */
347 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
348 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
351 case 3: /* 3-byte protocol */
352 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
353 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
357 err = input_register_device(elo->dev);
363 fail3: serio_close(serio);
364 fail2: serio_set_drvdata(serio, NULL);
365 fail1: input_free_device(input_dev);
371 * The serio driver structure.
374 static struct serio_device_id elo_serio_ids[] = {
384 MODULE_DEVICE_TABLE(serio, elo_serio_ids);
386 static struct serio_driver elo_drv = {
390 .description = DRIVER_DESC,
391 .id_table = elo_serio_ids,
392 .interrupt = elo_interrupt,
393 .connect = elo_connect,
394 .disconnect = elo_disconnect,
398 * The functions for inserting/removing us as a module.
401 static int __init elo_init(void)
403 serio_register_driver(&elo_drv);
407 static void __exit elo_exit(void)
409 serio_unregister_driver(&elo_drv);
412 module_init(elo_init);
413 module_exit(elo_exit);