xref: /linux/drivers/input/touchscreen/edt-ft5x06.c (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
1 /*
2  * Copyright (C) 2012 Simon Budig, <simon.budig@kernelconcepts.de>
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this library; if not, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
16  */
17 
18 /*
19  * This is a driver for the EDT "Polytouch" family of touch controllers
20  * based on the FocalTech FT5x06 line of chips.
21  *
22  * Development of this driver has been sponsored by Glyn:
23  *    http://www.glyn.com/Products/Displays
24  */
25 
26 #include <linux/module.h>
27 #include <linux/ratelimit.h>
28 #include <linux/interrupt.h>
29 #include <linux/input.h>
30 #include <linux/i2c.h>
31 #include <linux/uaccess.h>
32 #include <linux/delay.h>
33 #include <linux/debugfs.h>
34 #include <linux/slab.h>
35 #include <linux/gpio.h>
36 #include <linux/input/mt.h>
37 #include <linux/input/edt-ft5x06.h>
38 
39 #define MAX_SUPPORT_POINTS		5
40 
41 #define WORK_REGISTER_THRESHOLD		0x00
42 #define WORK_REGISTER_REPORT_RATE	0x08
43 #define WORK_REGISTER_GAIN		0x30
44 #define WORK_REGISTER_OFFSET		0x31
45 #define WORK_REGISTER_NUM_X		0x33
46 #define WORK_REGISTER_NUM_Y		0x34
47 
48 #define WORK_REGISTER_OPMODE		0x3c
49 #define FACTORY_REGISTER_OPMODE		0x01
50 
51 #define TOUCH_EVENT_DOWN		0x00
52 #define TOUCH_EVENT_UP			0x01
53 #define TOUCH_EVENT_ON			0x02
54 #define TOUCH_EVENT_RESERVED		0x03
55 
56 #define EDT_NAME_LEN			23
57 #define EDT_SWITCH_MODE_RETRIES		10
58 #define EDT_SWITCH_MODE_DELAY		5 /* msec */
59 #define EDT_RAW_DATA_RETRIES		100
60 #define EDT_RAW_DATA_DELAY		1 /* msec */
61 
62 struct edt_ft5x06_ts_data {
63 	struct i2c_client *client;
64 	struct input_dev *input;
65 	u16 num_x;
66 	u16 num_y;
67 
68 #if defined(CONFIG_DEBUG_FS)
69 	struct dentry *debug_dir;
70 	u8 *raw_buffer;
71 	size_t raw_bufsize;
72 #endif
73 
74 	struct mutex mutex;
75 	bool factory_mode;
76 	int threshold;
77 	int gain;
78 	int offset;
79 	int report_rate;
80 
81 	char name[EDT_NAME_LEN];
82 };
83 
84 static int edt_ft5x06_ts_readwrite(struct i2c_client *client,
85 				   u16 wr_len, u8 *wr_buf,
86 				   u16 rd_len, u8 *rd_buf)
87 {
88 	struct i2c_msg wrmsg[2];
89 	int i = 0;
90 	int ret;
91 
92 	if (wr_len) {
93 		wrmsg[i].addr  = client->addr;
94 		wrmsg[i].flags = 0;
95 		wrmsg[i].len = wr_len;
96 		wrmsg[i].buf = wr_buf;
97 		i++;
98 	}
99 	if (rd_len) {
100 		wrmsg[i].addr  = client->addr;
101 		wrmsg[i].flags = I2C_M_RD;
102 		wrmsg[i].len = rd_len;
103 		wrmsg[i].buf = rd_buf;
104 		i++;
105 	}
106 
107 	ret = i2c_transfer(client->adapter, wrmsg, i);
108 	if (ret < 0)
109 		return ret;
110 	if (ret != i)
111 		return -EIO;
112 
113 	return 0;
114 }
115 
116 static bool edt_ft5x06_ts_check_crc(struct edt_ft5x06_ts_data *tsdata,
117 				    u8 *buf, int buflen)
118 {
119 	int i;
120 	u8 crc = 0;
121 
122 	for (i = 0; i < buflen - 1; i++)
123 		crc ^= buf[i];
124 
125 	if (crc != buf[buflen-1]) {
126 		dev_err_ratelimited(&tsdata->client->dev,
127 				    "crc error: 0x%02x expected, got 0x%02x\n",
128 				    crc, buf[buflen-1]);
129 		return false;
130 	}
131 
132 	return true;
133 }
134 
135 static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
136 {
137 	struct edt_ft5x06_ts_data *tsdata = dev_id;
138 	struct device *dev = &tsdata->client->dev;
139 	u8 cmd = 0xf9;
140 	u8 rdbuf[26];
141 	int i, type, x, y, id;
142 	int error;
143 
144 	memset(rdbuf, 0, sizeof(rdbuf));
145 
146 	error = edt_ft5x06_ts_readwrite(tsdata->client,
147 					sizeof(cmd), &cmd,
148 					sizeof(rdbuf), rdbuf);
149 	if (error) {
150 		dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n",
151 				    error);
152 		goto out;
153 	}
154 
155 	if (rdbuf[0] != 0xaa || rdbuf[1] != 0xaa || rdbuf[2] != 26) {
156 		dev_err_ratelimited(dev, "Unexpected header: %02x%02x%02x!\n",
157 				    rdbuf[0], rdbuf[1], rdbuf[2]);
158 		goto out;
159 	}
160 
161 	if (!edt_ft5x06_ts_check_crc(tsdata, rdbuf, 26))
162 		goto out;
163 
164 	for (i = 0; i < MAX_SUPPORT_POINTS; i++) {
165 		u8 *buf = &rdbuf[i * 4 + 5];
166 		bool down;
167 
168 		type = buf[0] >> 6;
169 		/* ignore Reserved events */
170 		if (type == TOUCH_EVENT_RESERVED)
171 			continue;
172 
173 		x = ((buf[0] << 8) | buf[1]) & 0x0fff;
174 		y = ((buf[2] << 8) | buf[3]) & 0x0fff;
175 		id = (buf[2] >> 4) & 0x0f;
176 		down = (type != TOUCH_EVENT_UP);
177 
178 		input_mt_slot(tsdata->input, id);
179 		input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER, down);
180 
181 		if (!down)
182 			continue;
183 
184 		input_report_abs(tsdata->input, ABS_MT_POSITION_X, x);
185 		input_report_abs(tsdata->input, ABS_MT_POSITION_Y, y);
186 	}
187 
188 	input_mt_report_pointer_emulation(tsdata->input, true);
189 	input_sync(tsdata->input);
190 
191 out:
192 	return IRQ_HANDLED;
193 }
194 
195 static int edt_ft5x06_register_write(struct edt_ft5x06_ts_data *tsdata,
196 				     u8 addr, u8 value)
197 {
198 	u8 wrbuf[4];
199 
200 	wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
201 	wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
202 	wrbuf[2] = value;
203 	wrbuf[3] = wrbuf[0] ^ wrbuf[1] ^ wrbuf[2];
204 
205 	return edt_ft5x06_ts_readwrite(tsdata->client, 4, wrbuf, 0, NULL);
206 }
207 
208 static int edt_ft5x06_register_read(struct edt_ft5x06_ts_data *tsdata,
209 				    u8 addr)
210 {
211 	u8 wrbuf[2], rdbuf[2];
212 	int error;
213 
214 	wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
215 	wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
216 	wrbuf[1] |= tsdata->factory_mode ? 0x80 : 0x40;
217 
218 	error = edt_ft5x06_ts_readwrite(tsdata->client, 2, wrbuf, 2, rdbuf);
219 	if (error)
220 		return error;
221 
222 	if ((wrbuf[0] ^ wrbuf[1] ^ rdbuf[0]) != rdbuf[1]) {
223 		dev_err(&tsdata->client->dev,
224 			"crc error: 0x%02x expected, got 0x%02x\n",
225 			wrbuf[0] ^ wrbuf[1] ^ rdbuf[0], rdbuf[1]);
226 		return -EIO;
227 	}
228 
229 	return rdbuf[0];
230 }
231 
232 struct edt_ft5x06_attribute {
233 	struct device_attribute dattr;
234 	size_t field_offset;
235 	u8 limit_low;
236 	u8 limit_high;
237 	u8 addr;
238 };
239 
240 #define EDT_ATTR(_field, _mode, _addr, _limit_low, _limit_high)		\
241 	struct edt_ft5x06_attribute edt_ft5x06_attr_##_field = {	\
242 		.dattr = __ATTR(_field, _mode,				\
243 				edt_ft5x06_setting_show,		\
244 				edt_ft5x06_setting_store),		\
245 		.field_offset =						\
246 			offsetof(struct edt_ft5x06_ts_data, _field),	\
247 		.limit_low = _limit_low,				\
248 		.limit_high = _limit_high,				\
249 		.addr = _addr,						\
250 	}
251 
252 static ssize_t edt_ft5x06_setting_show(struct device *dev,
253 				       struct device_attribute *dattr,
254 				       char *buf)
255 {
256 	struct i2c_client *client = to_i2c_client(dev);
257 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
258 	struct edt_ft5x06_attribute *attr =
259 			container_of(dattr, struct edt_ft5x06_attribute, dattr);
260 	u8 *field = (u8 *)((char *)tsdata + attr->field_offset);
261 	int val;
262 	size_t count = 0;
263 	int error = 0;
264 
265 	mutex_lock(&tsdata->mutex);
266 
267 	if (tsdata->factory_mode) {
268 		error = -EIO;
269 		goto out;
270 	}
271 
272 	val = edt_ft5x06_register_read(tsdata, attr->addr);
273 	if (val < 0) {
274 		error = val;
275 		dev_err(&tsdata->client->dev,
276 			"Failed to fetch attribute %s, error %d\n",
277 			dattr->attr.name, error);
278 		goto out;
279 	}
280 
281 	if (val != *field) {
282 		dev_warn(&tsdata->client->dev,
283 			 "%s: read (%d) and stored value (%d) differ\n",
284 			 dattr->attr.name, val, *field);
285 		*field = val;
286 	}
287 
288 	count = scnprintf(buf, PAGE_SIZE, "%d\n", val);
289 out:
290 	mutex_unlock(&tsdata->mutex);
291 	return error ?: count;
292 }
293 
294 static ssize_t edt_ft5x06_setting_store(struct device *dev,
295 					struct device_attribute *dattr,
296 					const char *buf, size_t count)
297 {
298 	struct i2c_client *client = to_i2c_client(dev);
299 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
300 	struct edt_ft5x06_attribute *attr =
301 			container_of(dattr, struct edt_ft5x06_attribute, dattr);
302 	u8 *field = (u8 *)((char *)tsdata + attr->field_offset);
303 	unsigned int val;
304 	int error;
305 
306 	mutex_lock(&tsdata->mutex);
307 
308 	if (tsdata->factory_mode) {
309 		error = -EIO;
310 		goto out;
311 	}
312 
313 	error = kstrtouint(buf, 0, &val);
314 	if (error)
315 		goto out;
316 
317 	if (val < attr->limit_low || val > attr->limit_high) {
318 		error = -ERANGE;
319 		goto out;
320 	}
321 
322 	error = edt_ft5x06_register_write(tsdata, attr->addr, val);
323 	if (error) {
324 		dev_err(&tsdata->client->dev,
325 			"Failed to update attribute %s, error: %d\n",
326 			dattr->attr.name, error);
327 		goto out;
328 	}
329 
330 	*field = val;
331 
332 out:
333 	mutex_unlock(&tsdata->mutex);
334 	return error ?: count;
335 }
336 
337 static EDT_ATTR(gain, S_IWUSR | S_IRUGO, WORK_REGISTER_GAIN, 0, 31);
338 static EDT_ATTR(offset, S_IWUSR | S_IRUGO, WORK_REGISTER_OFFSET, 0, 31);
339 static EDT_ATTR(threshold, S_IWUSR | S_IRUGO,
340 		WORK_REGISTER_THRESHOLD, 20, 80);
341 static EDT_ATTR(report_rate, S_IWUSR | S_IRUGO,
342 		WORK_REGISTER_REPORT_RATE, 3, 14);
343 
344 static struct attribute *edt_ft5x06_attrs[] = {
345 	&edt_ft5x06_attr_gain.dattr.attr,
346 	&edt_ft5x06_attr_offset.dattr.attr,
347 	&edt_ft5x06_attr_threshold.dattr.attr,
348 	&edt_ft5x06_attr_report_rate.dattr.attr,
349 	NULL
350 };
351 
352 static const struct attribute_group edt_ft5x06_attr_group = {
353 	.attrs = edt_ft5x06_attrs,
354 };
355 
356 #ifdef CONFIG_DEBUG_FS
357 static int edt_ft5x06_factory_mode(struct edt_ft5x06_ts_data *tsdata)
358 {
359 	struct i2c_client *client = tsdata->client;
360 	int retries = EDT_SWITCH_MODE_RETRIES;
361 	int ret;
362 	int error;
363 
364 	disable_irq(client->irq);
365 
366 	if (!tsdata->raw_buffer) {
367 		tsdata->raw_bufsize = tsdata->num_x * tsdata->num_y *
368 				      sizeof(u16);
369 		tsdata->raw_buffer = kzalloc(tsdata->raw_bufsize, GFP_KERNEL);
370 		if (!tsdata->raw_buffer) {
371 			error = -ENOMEM;
372 			goto err_out;
373 		}
374 	}
375 
376 	/* mode register is 0x3c when in the work mode */
377 	error = edt_ft5x06_register_write(tsdata, WORK_REGISTER_OPMODE, 0x03);
378 	if (error) {
379 		dev_err(&client->dev,
380 			"failed to switch to factory mode, error %d\n", error);
381 		goto err_out;
382 	}
383 
384 	tsdata->factory_mode = true;
385 	do {
386 		mdelay(EDT_SWITCH_MODE_DELAY);
387 		/* mode register is 0x01 when in factory mode */
388 		ret = edt_ft5x06_register_read(tsdata, FACTORY_REGISTER_OPMODE);
389 		if (ret == 0x03)
390 			break;
391 	} while (--retries > 0);
392 
393 	if (retries == 0) {
394 		dev_err(&client->dev, "not in factory mode after %dms.\n",
395 			EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
396 		error = -EIO;
397 		goto err_out;
398 	}
399 
400 	return 0;
401 
402 err_out:
403 	kfree(tsdata->raw_buffer);
404 	tsdata->raw_buffer = NULL;
405 	tsdata->factory_mode = false;
406 	enable_irq(client->irq);
407 
408 	return error;
409 }
410 
411 static int edt_ft5x06_work_mode(struct edt_ft5x06_ts_data *tsdata)
412 {
413 	struct i2c_client *client = tsdata->client;
414 	int retries = EDT_SWITCH_MODE_RETRIES;
415 	int ret;
416 	int error;
417 
418 	/* mode register is 0x01 when in the factory mode */
419 	error = edt_ft5x06_register_write(tsdata, FACTORY_REGISTER_OPMODE, 0x1);
420 	if (error) {
421 		dev_err(&client->dev,
422 			"failed to switch to work mode, error: %d\n", error);
423 		return error;
424 	}
425 
426 	tsdata->factory_mode = false;
427 
428 	do {
429 		mdelay(EDT_SWITCH_MODE_DELAY);
430 		/* mode register is 0x01 when in factory mode */
431 		ret = edt_ft5x06_register_read(tsdata, WORK_REGISTER_OPMODE);
432 		if (ret == 0x01)
433 			break;
434 	} while (--retries > 0);
435 
436 	if (retries == 0) {
437 		dev_err(&client->dev, "not in work mode after %dms.\n",
438 			EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
439 		tsdata->factory_mode = true;
440 		return -EIO;
441 	}
442 
443 	if (tsdata->raw_buffer)
444 		kfree(tsdata->raw_buffer);
445 	tsdata->raw_buffer = NULL;
446 
447 	/* restore parameters */
448 	edt_ft5x06_register_write(tsdata, WORK_REGISTER_THRESHOLD,
449 				  tsdata->threshold);
450 	edt_ft5x06_register_write(tsdata, WORK_REGISTER_GAIN,
451 				  tsdata->gain);
452 	edt_ft5x06_register_write(tsdata, WORK_REGISTER_OFFSET,
453 				  tsdata->offset);
454 	edt_ft5x06_register_write(tsdata, WORK_REGISTER_REPORT_RATE,
455 				  tsdata->report_rate);
456 
457 	enable_irq(client->irq);
458 
459 	return 0;
460 }
461 
462 static int edt_ft5x06_debugfs_mode_get(void *data, u64 *mode)
463 {
464 	struct edt_ft5x06_ts_data *tsdata = data;
465 
466 	*mode = tsdata->factory_mode;
467 
468 	return 0;
469 };
470 
471 static int edt_ft5x06_debugfs_mode_set(void *data, u64 mode)
472 {
473 	struct edt_ft5x06_ts_data *tsdata = data;
474 	int retval = 0;
475 
476 	if (mode > 1)
477 		return -ERANGE;
478 
479 	mutex_lock(&tsdata->mutex);
480 
481 	if (mode != tsdata->factory_mode) {
482 		retval = mode ? edt_ft5x06_factory_mode(tsdata) :
483 			        edt_ft5x06_work_mode(tsdata);
484 	}
485 
486 	mutex_unlock(&tsdata->mutex);
487 
488 	return retval;
489 };
490 
491 DEFINE_SIMPLE_ATTRIBUTE(debugfs_mode_fops, edt_ft5x06_debugfs_mode_get,
492 			edt_ft5x06_debugfs_mode_set, "%llu\n");
493 
494 static int edt_ft5x06_debugfs_raw_data_open(struct inode *inode,
495 					    struct file *file)
496 {
497 	file->private_data = inode->i_private;
498 
499 	return 0;
500 }
501 
502 static ssize_t edt_ft5x06_debugfs_raw_data_read(struct file *file,
503 				char __user *buf, size_t count, loff_t *off)
504 {
505 	struct edt_ft5x06_ts_data *tsdata = file->private_data;
506 	struct i2c_client *client = tsdata->client;
507 	int retries  = EDT_RAW_DATA_RETRIES;
508 	int val, i, error;
509 	size_t read = 0;
510 	int colbytes;
511 	char wrbuf[3];
512 	u8 *rdbuf;
513 
514 	if (*off < 0 || *off >= tsdata->raw_bufsize)
515 		return 0;
516 
517 	mutex_lock(&tsdata->mutex);
518 
519 	if (!tsdata->factory_mode || !tsdata->raw_buffer) {
520 		error = -EIO;
521 		goto out;
522 	}
523 
524 	error = edt_ft5x06_register_write(tsdata, 0x08, 0x01);
525 	if (error) {
526 		dev_dbg(&client->dev,
527 			"failed to write 0x08 register, error %d\n", error);
528 		goto out;
529 	}
530 
531 	do {
532 		msleep(EDT_RAW_DATA_DELAY);
533 		val = edt_ft5x06_register_read(tsdata, 0x08);
534 		if (val < 1)
535 			break;
536 	} while (--retries > 0);
537 
538 	if (val < 0) {
539 		error = val;
540 		dev_dbg(&client->dev,
541 			"failed to read 0x08 register, error %d\n", error);
542 		goto out;
543 	}
544 
545 	if (retries == 0) {
546 		dev_dbg(&client->dev,
547 			"timed out waiting for register to settle\n");
548 		error = -ETIMEDOUT;
549 		goto out;
550 	}
551 
552 	rdbuf = tsdata->raw_buffer;
553 	colbytes = tsdata->num_y * sizeof(u16);
554 
555 	wrbuf[0] = 0xf5;
556 	wrbuf[1] = 0x0e;
557 	for (i = 0; i < tsdata->num_x; i++) {
558 		wrbuf[2] = i;  /* column index */
559 		error = edt_ft5x06_ts_readwrite(tsdata->client,
560 						sizeof(wrbuf), wrbuf,
561 						colbytes, rdbuf);
562 		if (error)
563 			goto out;
564 
565 		rdbuf += colbytes;
566 	}
567 
568 	read = min_t(size_t, count, tsdata->raw_bufsize - *off);
569 	if (copy_to_user(buf, tsdata->raw_buffer + *off, read)) {
570 		error = -EFAULT;
571 		goto out;
572 	}
573 
574 	*off += read;
575 out:
576 	mutex_unlock(&tsdata->mutex);
577 	return error ?: read;
578 };
579 
580 
581 static const struct file_operations debugfs_raw_data_fops = {
582 	.open = edt_ft5x06_debugfs_raw_data_open,
583 	.read = edt_ft5x06_debugfs_raw_data_read,
584 };
585 
586 static void __devinit
587 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
588 			      const char *debugfs_name)
589 {
590 	tsdata->debug_dir = debugfs_create_dir(debugfs_name, NULL);
591 	if (!tsdata->debug_dir)
592 		return;
593 
594 	debugfs_create_u16("num_x", S_IRUSR, tsdata->debug_dir, &tsdata->num_x);
595 	debugfs_create_u16("num_y", S_IRUSR, tsdata->debug_dir, &tsdata->num_y);
596 
597 	debugfs_create_file("mode", S_IRUSR | S_IWUSR,
598 			    tsdata->debug_dir, tsdata, &debugfs_mode_fops);
599 	debugfs_create_file("raw_data", S_IRUSR,
600 			    tsdata->debug_dir, tsdata, &debugfs_raw_data_fops);
601 }
602 
603 static void __devexit
604 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
605 {
606 	if (tsdata->debug_dir)
607 		debugfs_remove_recursive(tsdata->debug_dir);
608 	kfree(tsdata->raw_buffer);
609 }
610 
611 #else
612 
613 static inline void
614 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
615 			      const char *debugfs_name)
616 {
617 }
618 
619 static inline void
620 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
621 {
622 }
623 
624 #endif /* CONFIG_DEBUGFS */
625 
626 
627 
628 static int __devinit edt_ft5x06_ts_reset(struct i2c_client *client,
629 					 int reset_pin)
630 {
631 	int error;
632 
633 	if (gpio_is_valid(reset_pin)) {
634 		/* this pulls reset down, enabling the low active reset */
635 		error = gpio_request_one(reset_pin, GPIOF_OUT_INIT_LOW,
636 					 "edt-ft5x06 reset");
637 		if (error) {
638 			dev_err(&client->dev,
639 				"Failed to request GPIO %d as reset pin, error %d\n",
640 				reset_pin, error);
641 			return error;
642 		}
643 
644 		mdelay(50);
645 		gpio_set_value(reset_pin, 1);
646 		mdelay(100);
647 	}
648 
649 	return 0;
650 }
651 
652 static int __devinit edt_ft5x06_ts_identify(struct i2c_client *client,
653 					    char *model_name,
654 					    char *fw_version)
655 {
656 	u8 rdbuf[EDT_NAME_LEN];
657 	char *p;
658 	int error;
659 
660 	error = edt_ft5x06_ts_readwrite(client, 1, "\xbb",
661 					EDT_NAME_LEN - 1, rdbuf);
662 	if (error)
663 		return error;
664 
665 	/* remove last '$' end marker */
666 	rdbuf[EDT_NAME_LEN - 1] = '\0';
667 	if (rdbuf[EDT_NAME_LEN - 2] == '$')
668 		rdbuf[EDT_NAME_LEN - 2] = '\0';
669 
670 	/* look for Model/Version separator */
671 	p = strchr(rdbuf, '*');
672 	if (p)
673 		*p++ = '\0';
674 
675 	strlcpy(model_name, rdbuf + 1, EDT_NAME_LEN);
676 	strlcpy(fw_version, p ? p : "", EDT_NAME_LEN);
677 
678 	return 0;
679 }
680 
681 #define EDT_ATTR_CHECKSET(name, reg) \
682 	if (pdata->name >= edt_ft5x06_attr_##name.limit_low &&		\
683 	    pdata->name <= edt_ft5x06_attr_##name.limit_high)		\
684 		edt_ft5x06_register_write(tsdata, reg, pdata->name)
685 
686 static void __devinit
687 edt_ft5x06_ts_get_defaults(struct edt_ft5x06_ts_data *tsdata,
688 			   const struct edt_ft5x06_platform_data *pdata)
689 {
690 	if (!pdata->use_parameters)
691 		return;
692 
693 	/* pick up defaults from the platform data */
694 	EDT_ATTR_CHECKSET(threshold, WORK_REGISTER_THRESHOLD);
695 	EDT_ATTR_CHECKSET(gain, WORK_REGISTER_GAIN);
696 	EDT_ATTR_CHECKSET(offset, WORK_REGISTER_OFFSET);
697 	EDT_ATTR_CHECKSET(report_rate, WORK_REGISTER_REPORT_RATE);
698 }
699 
700 static void __devinit
701 edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata)
702 {
703 	tsdata->threshold = edt_ft5x06_register_read(tsdata,
704 						     WORK_REGISTER_THRESHOLD);
705 	tsdata->gain = edt_ft5x06_register_read(tsdata, WORK_REGISTER_GAIN);
706 	tsdata->offset = edt_ft5x06_register_read(tsdata, WORK_REGISTER_OFFSET);
707 	tsdata->report_rate = edt_ft5x06_register_read(tsdata,
708 						WORK_REGISTER_REPORT_RATE);
709 	tsdata->num_x = edt_ft5x06_register_read(tsdata, WORK_REGISTER_NUM_X);
710 	tsdata->num_y = edt_ft5x06_register_read(tsdata, WORK_REGISTER_NUM_Y);
711 }
712 
713 static int __devinit edt_ft5x06_ts_probe(struct i2c_client *client,
714 					 const struct i2c_device_id *id)
715 {
716 	const struct edt_ft5x06_platform_data *pdata =
717 						client->dev.platform_data;
718 	struct edt_ft5x06_ts_data *tsdata;
719 	struct input_dev *input;
720 	int error;
721 	char fw_version[EDT_NAME_LEN];
722 
723 	dev_dbg(&client->dev, "probing for EDT FT5x06 I2C\n");
724 
725 	if (!pdata) {
726 		dev_err(&client->dev, "no platform data?\n");
727 		return -EINVAL;
728 	}
729 
730 	error = edt_ft5x06_ts_reset(client, pdata->reset_pin);
731 	if (error)
732 		return error;
733 
734 	if (gpio_is_valid(pdata->irq_pin)) {
735 		error = gpio_request_one(pdata->irq_pin,
736 					 GPIOF_IN, "edt-ft5x06 irq");
737 		if (error) {
738 			dev_err(&client->dev,
739 				"Failed to request GPIO %d, error %d\n",
740 				pdata->irq_pin, error);
741 			return error;
742 		}
743 	}
744 
745 	tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
746 	input = input_allocate_device();
747 	if (!tsdata || !input) {
748 		dev_err(&client->dev, "failed to allocate driver data.\n");
749 		error = -ENOMEM;
750 		goto err_free_mem;
751 	}
752 
753 	mutex_init(&tsdata->mutex);
754 	tsdata->client = client;
755 	tsdata->input = input;
756 	tsdata->factory_mode = false;
757 
758 	error = edt_ft5x06_ts_identify(client, tsdata->name, fw_version);
759 	if (error) {
760 		dev_err(&client->dev, "touchscreen probe failed\n");
761 		goto err_free_mem;
762 	}
763 
764 	edt_ft5x06_ts_get_defaults(tsdata, pdata);
765 	edt_ft5x06_ts_get_parameters(tsdata);
766 
767 	dev_dbg(&client->dev,
768 		"Model \"%s\", Rev. \"%s\", %dx%d sensors\n",
769 		tsdata->name, fw_version, tsdata->num_x, tsdata->num_y);
770 
771 	input->name = tsdata->name;
772 	input->id.bustype = BUS_I2C;
773 	input->dev.parent = &client->dev;
774 
775 	__set_bit(EV_SYN, input->evbit);
776 	__set_bit(EV_KEY, input->evbit);
777 	__set_bit(EV_ABS, input->evbit);
778 	__set_bit(BTN_TOUCH, input->keybit);
779 	input_set_abs_params(input, ABS_X, 0, tsdata->num_x * 64 - 1, 0, 0);
780 	input_set_abs_params(input, ABS_Y, 0, tsdata->num_y * 64 - 1, 0, 0);
781 	input_set_abs_params(input, ABS_MT_POSITION_X,
782 			     0, tsdata->num_x * 64 - 1, 0, 0);
783 	input_set_abs_params(input, ABS_MT_POSITION_Y,
784 			     0, tsdata->num_y * 64 - 1, 0, 0);
785 	error = input_mt_init_slots(input, MAX_SUPPORT_POINTS, 0);
786 	if (error) {
787 		dev_err(&client->dev, "Unable to init MT slots.\n");
788 		goto err_free_mem;
789 	}
790 
791 	input_set_drvdata(input, tsdata);
792 	i2c_set_clientdata(client, tsdata);
793 
794 	error = request_threaded_irq(client->irq, NULL, edt_ft5x06_ts_isr,
795 				     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
796 				     client->name, tsdata);
797 	if (error) {
798 		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
799 		goto err_free_mem;
800 	}
801 
802 	error = sysfs_create_group(&client->dev.kobj, &edt_ft5x06_attr_group);
803 	if (error)
804 		goto err_free_irq;
805 
806 	error = input_register_device(input);
807 	if (error)
808 		goto err_remove_attrs;
809 
810 	edt_ft5x06_ts_prepare_debugfs(tsdata, dev_driver_string(&client->dev));
811 	device_init_wakeup(&client->dev, 1);
812 
813 	dev_dbg(&client->dev,
814 		"EDT FT5x06 initialized: IRQ pin %d, Reset pin %d.\n",
815 		pdata->irq_pin, pdata->reset_pin);
816 
817 	return 0;
818 
819 err_remove_attrs:
820 	sysfs_remove_group(&client->dev.kobj, &edt_ft5x06_attr_group);
821 err_free_irq:
822 	free_irq(client->irq, tsdata);
823 err_free_mem:
824 	input_free_device(input);
825 	kfree(tsdata);
826 
827 	if (gpio_is_valid(pdata->irq_pin))
828 		gpio_free(pdata->irq_pin);
829 
830 	return error;
831 }
832 
833 static int __devexit edt_ft5x06_ts_remove(struct i2c_client *client)
834 {
835 	const struct edt_ft5x06_platform_data *pdata =
836 						dev_get_platdata(&client->dev);
837 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
838 
839 	edt_ft5x06_ts_teardown_debugfs(tsdata);
840 	sysfs_remove_group(&client->dev.kobj, &edt_ft5x06_attr_group);
841 
842 	free_irq(client->irq, tsdata);
843 	input_unregister_device(tsdata->input);
844 
845 	if (gpio_is_valid(pdata->irq_pin))
846 		gpio_free(pdata->irq_pin);
847 	if (gpio_is_valid(pdata->reset_pin))
848 		gpio_free(pdata->reset_pin);
849 
850 	kfree(tsdata);
851 
852 	return 0;
853 }
854 
855 #ifdef CONFIG_PM_SLEEP
856 static int edt_ft5x06_ts_suspend(struct device *dev)
857 {
858 	struct i2c_client *client = to_i2c_client(dev);
859 
860 	if (device_may_wakeup(dev))
861 		enable_irq_wake(client->irq);
862 
863 	return 0;
864 }
865 
866 static int edt_ft5x06_ts_resume(struct device *dev)
867 {
868 	struct i2c_client *client = to_i2c_client(dev);
869 
870 	if (device_may_wakeup(dev))
871 		disable_irq_wake(client->irq);
872 
873 	return 0;
874 }
875 #endif
876 
877 static SIMPLE_DEV_PM_OPS(edt_ft5x06_ts_pm_ops,
878 			 edt_ft5x06_ts_suspend, edt_ft5x06_ts_resume);
879 
880 static const struct i2c_device_id edt_ft5x06_ts_id[] = {
881 	{ "edt-ft5x06", 0 },
882 	{ }
883 };
884 MODULE_DEVICE_TABLE(i2c, edt_ft5x06_ts_id);
885 
886 static struct i2c_driver edt_ft5x06_ts_driver = {
887 	.driver = {
888 		.owner = THIS_MODULE,
889 		.name = "edt_ft5x06",
890 		.pm = &edt_ft5x06_ts_pm_ops,
891 	},
892 	.id_table = edt_ft5x06_ts_id,
893 	.probe    = edt_ft5x06_ts_probe,
894 	.remove   = __devexit_p(edt_ft5x06_ts_remove),
895 };
896 
897 module_i2c_driver(edt_ft5x06_ts_driver);
898 
899 MODULE_AUTHOR("Simon Budig <simon.budig@kernelconcepts.de>");
900 MODULE_DESCRIPTION("EDT FT5x06 I2C Touchscreen Driver");
901 MODULE_LICENSE("GPL");
902