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)
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_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]);
99 input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]);
100 if (elo->data[2] & ELO10_PRESSURE)
101 input_report_abs(dev, ABS_PRESSURE,
102 (elo->data[8] << 8) | elo->data[7]);
103 input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH);
105 } else if (elo->data[1] == ELO10_ACK_PACKET) {
106 if (elo->data[2] == '0')
107 elo->expected_packet = ELO10_TOUCH_PACKET;
108 complete(&elo->cmd_done);
110 memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN);
111 elo->expected_packet = ELO10_ACK_PACKET;
118 static void elo_process_data_6(struct elo *elo, unsigned char data)
120 struct input_dev *dev = elo->dev;
122 elo->data[elo->idx] = data;
124 switch (elo->idx++) {
126 case 0: if ((data & 0xc0) != 0xc0) elo->idx = 0; break;
127 case 1: if ((data & 0xc0) != 0x80) elo->idx = 0; break;
128 case 2: if ((data & 0xc0) != 0x40) elo->idx = 0; break;
136 input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f));
137 input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f));
140 input_report_key(dev, BTN_TOUCH, 1);
155 if ((data & 0xf0) == 0) {
156 input_report_abs(dev, ABS_PRESSURE, elo->data[5]);
157 input_report_key(dev, BTN_TOUCH, !!elo->data[5]);
165 static void elo_process_data_3(struct elo *elo, unsigned char data)
167 struct input_dev *dev = elo->dev;
169 elo->data[elo->idx] = data;
171 switch (elo->idx++) {
174 if ((data & 0x7f) != 0x01)
178 input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80));
179 input_report_abs(dev, ABS_X, elo->data[1]);
180 input_report_abs(dev, ABS_Y, elo->data[2]);
187 static irqreturn_t elo_interrupt(struct serio *serio,
188 unsigned char data, unsigned int flags)
190 struct elo *elo = serio_get_drvdata(serio);
194 elo_process_data_10(elo, data);
199 elo_process_data_6(elo, data);
203 elo_process_data_3(elo, data);
210 static int elo_command_10(struct elo *elo, unsigned char *packet)
214 unsigned char csum = 0xaa + ELO10_LEAD_BYTE;
216 mutex_lock(&elo->cmd_mutex);
218 serio_pause_rx(elo->serio);
219 elo->expected_packet = toupper(packet[0]);
220 init_completion(&elo->cmd_done);
221 serio_continue_rx(elo->serio);
223 if (serio_write(elo->serio, ELO10_LEAD_BYTE))
226 for (i = 0; i < ELO10_PACKET_LEN; i++) {
228 if (serio_write(elo->serio, packet[i]))
232 if (serio_write(elo->serio, csum))
235 wait_for_completion_timeout(&elo->cmd_done, HZ);
237 if (elo->expected_packet == ELO10_TOUCH_PACKET) {
238 /* We are back in reporting mode, the command was ACKed */
239 memcpy(packet, elo->response, ELO10_PACKET_LEN);
244 mutex_unlock(&elo->cmd_mutex);
248 static int elo_setup_10(struct elo *elo)
250 static const char *elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" };
251 struct input_dev *dev = elo->dev;
252 unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD };
254 if (elo_command_10(elo, packet))
257 dev->id.version = (packet[5] << 8) | packet[4];
259 input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0);
260 input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0);
261 if (packet[3] & ELO10_PRESSURE)
262 input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
264 printk(KERN_INFO "elo: %sTouch touchscreen, fw: %02x.%02x, "
265 "features: %x02x, controller: 0x%02x\n",
266 elo_types[(packet[1] -'0') & 0x03],
267 packet[5], packet[4], packet[3], packet[7]);
273 * elo_disconnect() is the opposite of elo_connect()
276 static void elo_disconnect(struct serio *serio)
278 struct elo *elo = serio_get_drvdata(serio);
280 input_get_device(elo->dev);
281 input_unregister_device(elo->dev);
283 serio_set_drvdata(serio, NULL);
284 input_put_device(elo->dev);
289 * elo_connect() is the routine that is called when someone adds a
290 * new serio device that supports Gunze protocol and registers it as
294 static int elo_connect(struct serio *serio, struct serio_driver *drv)
297 struct input_dev *input_dev;
300 elo = kzalloc(sizeof(struct elo), GFP_KERNEL);
301 input_dev = input_allocate_device();
302 if (!elo || !input_dev) {
308 elo->id = serio->id.id;
309 elo->dev = input_dev;
310 elo->expected_packet = ELO10_TOUCH_PACKET;
311 mutex_init(&elo->cmd_mutex);
312 init_completion(&elo->cmd_done);
313 snprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys);
315 input_dev->private = elo;
316 input_dev->name = "Elo Serial TouchScreen";
317 input_dev->phys = elo->phys;
318 input_dev->id.bustype = BUS_RS232;
319 input_dev->id.vendor = SERIO_ELO;
320 input_dev->id.product = elo->id;
321 input_dev->id.version = 0x0100;
322 input_dev->cdev.dev = &serio->dev;
324 input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_ABS);
325 input_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
327 serio_set_drvdata(serio, elo);
328 err = serio_open(serio, drv);
334 case 0: /* 10-byte protocol */
335 if (elo_setup_10(elo))
340 case 1: /* 6-byte protocol */
341 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0);
343 case 2: /* 4-byte protocol */
344 input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0);
345 input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0);
348 case 3: /* 3-byte protocol */
349 input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0);
350 input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0);
354 err = input_register_device(elo->dev);
360 fail3: serio_close(serio);
361 fail2: serio_set_drvdata(serio, NULL);
362 fail1: input_free_device(input_dev);
368 * The serio driver structure.
371 static struct serio_device_id elo_serio_ids[] = {
381 MODULE_DEVICE_TABLE(serio, elo_serio_ids);
383 static struct serio_driver elo_drv = {
387 .description = DRIVER_DESC,
388 .id_table = elo_serio_ids,
389 .interrupt = elo_interrupt,
390 .connect = elo_connect,
391 .disconnect = elo_disconnect,
395 * The functions for inserting/removing us as a module.
398 static int __init elo_init(void)
400 return serio_register_driver(&elo_drv);
403 static void __exit elo_exit(void)
405 serio_unregister_driver(&elo_drv);
408 module_init(elo_init);
409 module_exit(elo_exit);