1 /*
2  * Copyright (C) 2012 Simon Budig, <simon.budig@kernelconcepts.de>
3  * Daniel Wagener <daniel.wagener@kernelconcepts.de> (M09 firmware support)
4  * Lothar Waßmann <LW@KARO-electronics.de> (DT support)
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public
16  * License along with this library; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19 
20 /*
21  * This is a driver for the EDT "Polytouch" family of touch controllers
22  * based on the FocalTech FT5x06 line of chips.
23  *
24  * Development of this driver has been sponsored by Glyn:
25  *    http://www.glyn.com/Products/Displays
26  */
27 
28 #include <linux/module.h>
29 #include <linux/ratelimit.h>
30 #include <linux/irq.h>
31 #include <linux/interrupt.h>
32 #include <linux/input.h>
33 #include <linux/i2c.h>
34 #include <linux/uaccess.h>
35 #include <linux/delay.h>
36 #include <linux/debugfs.h>
37 #include <linux/slab.h>
38 #include <linux/gpio/consumer.h>
39 #include <linux/input/mt.h>
40 #include <linux/input/touchscreen.h>
41 #include <linux/of_device.h>
42 
43 #define WORK_REGISTER_THRESHOLD		0x00
44 #define WORK_REGISTER_REPORT_RATE	0x08
45 #define WORK_REGISTER_GAIN		0x30
46 #define WORK_REGISTER_OFFSET		0x31
47 #define WORK_REGISTER_NUM_X		0x33
48 #define WORK_REGISTER_NUM_Y		0x34
49 
50 #define M09_REGISTER_THRESHOLD		0x80
51 #define M09_REGISTER_GAIN		0x92
52 #define M09_REGISTER_OFFSET		0x93
53 #define M09_REGISTER_NUM_X		0x94
54 #define M09_REGISTER_NUM_Y		0x95
55 
56 #define NO_REGISTER			0xff
57 
58 #define WORK_REGISTER_OPMODE		0x3c
59 #define FACTORY_REGISTER_OPMODE		0x01
60 
61 #define TOUCH_EVENT_DOWN		0x00
62 #define TOUCH_EVENT_UP			0x01
63 #define TOUCH_EVENT_ON			0x02
64 #define TOUCH_EVENT_RESERVED		0x03
65 
66 #define EDT_NAME_LEN			23
67 #define EDT_SWITCH_MODE_RETRIES		10
68 #define EDT_SWITCH_MODE_DELAY		5 /* msec */
69 #define EDT_RAW_DATA_RETRIES		100
70 #define EDT_RAW_DATA_DELAY		1000 /* usec */
71 
72 enum edt_ver {
73 	EDT_M06,
74 	EDT_M09,
75 	EDT_M12,
76 	GENERIC_FT,
77 };
78 
79 struct edt_reg_addr {
80 	int reg_threshold;
81 	int reg_report_rate;
82 	int reg_gain;
83 	int reg_offset;
84 	int reg_num_x;
85 	int reg_num_y;
86 };
87 
88 struct edt_ft5x06_ts_data {
89 	struct i2c_client *client;
90 	struct input_dev *input;
91 	struct touchscreen_properties prop;
92 	u16 num_x;
93 	u16 num_y;
94 
95 	struct gpio_desc *reset_gpio;
96 	struct gpio_desc *wake_gpio;
97 
98 #if defined(CONFIG_DEBUG_FS)
99 	struct dentry *debug_dir;
100 	u8 *raw_buffer;
101 	size_t raw_bufsize;
102 #endif
103 
104 	struct mutex mutex;
105 	bool factory_mode;
106 	int threshold;
107 	int gain;
108 	int offset;
109 	int report_rate;
110 	int max_support_points;
111 
112 	char name[EDT_NAME_LEN];
113 
114 	struct edt_reg_addr reg_addr;
115 	enum edt_ver version;
116 };
117 
118 struct edt_i2c_chip_data {
119 	int  max_support_points;
120 };
121 
122 static int edt_ft5x06_ts_readwrite(struct i2c_client *client,
123 				   u16 wr_len, u8 *wr_buf,
124 				   u16 rd_len, u8 *rd_buf)
125 {
126 	struct i2c_msg wrmsg[2];
127 	int i = 0;
128 	int ret;
129 
130 	if (wr_len) {
131 		wrmsg[i].addr  = client->addr;
132 		wrmsg[i].flags = 0;
133 		wrmsg[i].len = wr_len;
134 		wrmsg[i].buf = wr_buf;
135 		i++;
136 	}
137 	if (rd_len) {
138 		wrmsg[i].addr  = client->addr;
139 		wrmsg[i].flags = I2C_M_RD;
140 		wrmsg[i].len = rd_len;
141 		wrmsg[i].buf = rd_buf;
142 		i++;
143 	}
144 
145 	ret = i2c_transfer(client->adapter, wrmsg, i);
146 	if (ret < 0)
147 		return ret;
148 	if (ret != i)
149 		return -EIO;
150 
151 	return 0;
152 }
153 
154 static bool edt_ft5x06_ts_check_crc(struct edt_ft5x06_ts_data *tsdata,
155 				    u8 *buf, int buflen)
156 {
157 	int i;
158 	u8 crc = 0;
159 
160 	for (i = 0; i < buflen - 1; i++)
161 		crc ^= buf[i];
162 
163 	if (crc != buf[buflen-1]) {
164 		dev_err_ratelimited(&tsdata->client->dev,
165 				    "crc error: 0x%02x expected, got 0x%02x\n",
166 				    crc, buf[buflen-1]);
167 		return false;
168 	}
169 
170 	return true;
171 }
172 
173 static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
174 {
175 	struct edt_ft5x06_ts_data *tsdata = dev_id;
176 	struct device *dev = &tsdata->client->dev;
177 	u8 cmd;
178 	u8 rdbuf[63];
179 	int i, type, x, y, id;
180 	int offset, tplen, datalen, crclen;
181 	int error;
182 
183 	switch (tsdata->version) {
184 	case EDT_M06:
185 		cmd = 0xf9; /* tell the controller to send touch data */
186 		offset = 5; /* where the actual touch data starts */
187 		tplen = 4;  /* data comes in so called frames */
188 		crclen = 1; /* length of the crc data */
189 		break;
190 
191 	case EDT_M09:
192 	case EDT_M12:
193 	case GENERIC_FT:
194 		cmd = 0x0;
195 		offset = 3;
196 		tplen = 6;
197 		crclen = 0;
198 		break;
199 
200 	default:
201 		goto out;
202 	}
203 
204 	memset(rdbuf, 0, sizeof(rdbuf));
205 	datalen = tplen * tsdata->max_support_points + offset + crclen;
206 
207 	error = edt_ft5x06_ts_readwrite(tsdata->client,
208 					sizeof(cmd), &cmd,
209 					datalen, rdbuf);
210 	if (error) {
211 		dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n",
212 				    error);
213 		goto out;
214 	}
215 
216 	/* M09/M12 does not send header or CRC */
217 	if (tsdata->version == EDT_M06) {
218 		if (rdbuf[0] != 0xaa || rdbuf[1] != 0xaa ||
219 			rdbuf[2] != datalen) {
220 			dev_err_ratelimited(dev,
221 					"Unexpected header: %02x%02x%02x!\n",
222 					rdbuf[0], rdbuf[1], rdbuf[2]);
223 			goto out;
224 		}
225 
226 		if (!edt_ft5x06_ts_check_crc(tsdata, rdbuf, datalen))
227 			goto out;
228 	}
229 
230 	for (i = 0; i < tsdata->max_support_points; i++) {
231 		u8 *buf = &rdbuf[i * tplen + offset];
232 		bool down;
233 
234 		type = buf[0] >> 6;
235 		/* ignore Reserved events */
236 		if (type == TOUCH_EVENT_RESERVED)
237 			continue;
238 
239 		/* M06 sometimes sends bogus coordinates in TOUCH_DOWN */
240 		if (tsdata->version == EDT_M06 && type == TOUCH_EVENT_DOWN)
241 			continue;
242 
243 		x = ((buf[0] << 8) | buf[1]) & 0x0fff;
244 		y = ((buf[2] << 8) | buf[3]) & 0x0fff;
245 		id = (buf[2] >> 4) & 0x0f;
246 		down = type != TOUCH_EVENT_UP;
247 
248 		input_mt_slot(tsdata->input, id);
249 		input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER, down);
250 
251 		if (!down)
252 			continue;
253 
254 		touchscreen_report_pos(tsdata->input, &tsdata->prop, x, y,
255 				       true);
256 	}
257 
258 	input_mt_report_pointer_emulation(tsdata->input, true);
259 	input_sync(tsdata->input);
260 
261 out:
262 	return IRQ_HANDLED;
263 }
264 
265 static int edt_ft5x06_register_write(struct edt_ft5x06_ts_data *tsdata,
266 				     u8 addr, u8 value)
267 {
268 	u8 wrbuf[4];
269 
270 	switch (tsdata->version) {
271 	case EDT_M06:
272 		wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
273 		wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
274 		wrbuf[2] = value;
275 		wrbuf[3] = wrbuf[0] ^ wrbuf[1] ^ wrbuf[2];
276 		return edt_ft5x06_ts_readwrite(tsdata->client, 4,
277 					wrbuf, 0, NULL);
278 	case EDT_M09:
279 	case EDT_M12:
280 	case GENERIC_FT:
281 		wrbuf[0] = addr;
282 		wrbuf[1] = value;
283 
284 		return edt_ft5x06_ts_readwrite(tsdata->client, 2,
285 					wrbuf, 0, NULL);
286 
287 	default:
288 		return -EINVAL;
289 	}
290 }
291 
292 static int edt_ft5x06_register_read(struct edt_ft5x06_ts_data *tsdata,
293 				    u8 addr)
294 {
295 	u8 wrbuf[2], rdbuf[2];
296 	int error;
297 
298 	switch (tsdata->version) {
299 	case EDT_M06:
300 		wrbuf[0] = tsdata->factory_mode ? 0xf3 : 0xfc;
301 		wrbuf[1] = tsdata->factory_mode ? addr & 0x7f : addr & 0x3f;
302 		wrbuf[1] |= tsdata->factory_mode ? 0x80 : 0x40;
303 
304 		error = edt_ft5x06_ts_readwrite(tsdata->client, 2, wrbuf, 2,
305 						rdbuf);
306 		if (error)
307 			return error;
308 
309 		if ((wrbuf[0] ^ wrbuf[1] ^ rdbuf[0]) != rdbuf[1]) {
310 			dev_err(&tsdata->client->dev,
311 				"crc error: 0x%02x expected, got 0x%02x\n",
312 				wrbuf[0] ^ wrbuf[1] ^ rdbuf[0],
313 				rdbuf[1]);
314 			return -EIO;
315 		}
316 		break;
317 
318 	case EDT_M09:
319 	case EDT_M12:
320 	case GENERIC_FT:
321 		wrbuf[0] = addr;
322 		error = edt_ft5x06_ts_readwrite(tsdata->client, 1,
323 						wrbuf, 1, rdbuf);
324 		if (error)
325 			return error;
326 		break;
327 
328 	default:
329 		return -EINVAL;
330 	}
331 
332 	return rdbuf[0];
333 }
334 
335 struct edt_ft5x06_attribute {
336 	struct device_attribute dattr;
337 	size_t field_offset;
338 	u8 limit_low;
339 	u8 limit_high;
340 	u8 addr_m06;
341 	u8 addr_m09;
342 };
343 
344 #define EDT_ATTR(_field, _mode, _addr_m06, _addr_m09,			\
345 		_limit_low, _limit_high)				\
346 	struct edt_ft5x06_attribute edt_ft5x06_attr_##_field = {	\
347 		.dattr = __ATTR(_field, _mode,				\
348 				edt_ft5x06_setting_show,		\
349 				edt_ft5x06_setting_store),		\
350 		.field_offset = offsetof(struct edt_ft5x06_ts_data, _field), \
351 		.addr_m06 = _addr_m06,					\
352 		.addr_m09 = _addr_m09,					\
353 		.limit_low = _limit_low,				\
354 		.limit_high = _limit_high,				\
355 	}
356 
357 static ssize_t edt_ft5x06_setting_show(struct device *dev,
358 				       struct device_attribute *dattr,
359 				       char *buf)
360 {
361 	struct i2c_client *client = to_i2c_client(dev);
362 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
363 	struct edt_ft5x06_attribute *attr =
364 			container_of(dattr, struct edt_ft5x06_attribute, dattr);
365 	u8 *field = (u8 *)tsdata + attr->field_offset;
366 	int val;
367 	size_t count = 0;
368 	int error = 0;
369 	u8 addr;
370 
371 	mutex_lock(&tsdata->mutex);
372 
373 	if (tsdata->factory_mode) {
374 		error = -EIO;
375 		goto out;
376 	}
377 
378 	switch (tsdata->version) {
379 	case EDT_M06:
380 		addr = attr->addr_m06;
381 		break;
382 
383 	case EDT_M09:
384 	case EDT_M12:
385 	case GENERIC_FT:
386 		addr = attr->addr_m09;
387 		break;
388 
389 	default:
390 		error = -ENODEV;
391 		goto out;
392 	}
393 
394 	if (addr != NO_REGISTER) {
395 		val = edt_ft5x06_register_read(tsdata, addr);
396 		if (val < 0) {
397 			error = val;
398 			dev_err(&tsdata->client->dev,
399 				"Failed to fetch attribute %s, error %d\n",
400 				dattr->attr.name, error);
401 			goto out;
402 		}
403 	} else {
404 		val = *field;
405 	}
406 
407 	if (val != *field) {
408 		dev_warn(&tsdata->client->dev,
409 			 "%s: read (%d) and stored value (%d) differ\n",
410 			 dattr->attr.name, val, *field);
411 		*field = val;
412 	}
413 
414 	count = scnprintf(buf, PAGE_SIZE, "%d\n", val);
415 out:
416 	mutex_unlock(&tsdata->mutex);
417 	return error ?: count;
418 }
419 
420 static ssize_t edt_ft5x06_setting_store(struct device *dev,
421 					struct device_attribute *dattr,
422 					const char *buf, size_t count)
423 {
424 	struct i2c_client *client = to_i2c_client(dev);
425 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
426 	struct edt_ft5x06_attribute *attr =
427 			container_of(dattr, struct edt_ft5x06_attribute, dattr);
428 	u8 *field = (u8 *)tsdata + attr->field_offset;
429 	unsigned int val;
430 	int error;
431 	u8 addr;
432 
433 	mutex_lock(&tsdata->mutex);
434 
435 	if (tsdata->factory_mode) {
436 		error = -EIO;
437 		goto out;
438 	}
439 
440 	error = kstrtouint(buf, 0, &val);
441 	if (error)
442 		goto out;
443 
444 	if (val < attr->limit_low || val > attr->limit_high) {
445 		error = -ERANGE;
446 		goto out;
447 	}
448 
449 	switch (tsdata->version) {
450 	case EDT_M06:
451 		addr = attr->addr_m06;
452 		break;
453 
454 	case EDT_M09:
455 	case EDT_M12:
456 	case GENERIC_FT:
457 		addr = attr->addr_m09;
458 		break;
459 
460 	default:
461 		error = -ENODEV;
462 		goto out;
463 	}
464 
465 	if (addr != NO_REGISTER) {
466 		error = edt_ft5x06_register_write(tsdata, addr, val);
467 		if (error) {
468 			dev_err(&tsdata->client->dev,
469 				"Failed to update attribute %s, error: %d\n",
470 				dattr->attr.name, error);
471 			goto out;
472 		}
473 	}
474 	*field = val;
475 
476 out:
477 	mutex_unlock(&tsdata->mutex);
478 	return error ?: count;
479 }
480 
481 /* m06, m09: range 0-31, m12: range 0-5 */
482 static EDT_ATTR(gain, S_IWUSR | S_IRUGO, WORK_REGISTER_GAIN,
483 		M09_REGISTER_GAIN, 0, 31);
484 /* m06, m09: range 0-31, m12: range 0-16 */
485 static EDT_ATTR(offset, S_IWUSR | S_IRUGO, WORK_REGISTER_OFFSET,
486 		M09_REGISTER_OFFSET, 0, 31);
487 /* m06: range 20 to 80, m09: range 0 to 30, m12: range 1 to 255... */
488 static EDT_ATTR(threshold, S_IWUSR | S_IRUGO, WORK_REGISTER_THRESHOLD,
489 		M09_REGISTER_THRESHOLD, 0, 255);
490 /* m06: range 3 to 14, m12: (0x64: 100Hz) */
491 static EDT_ATTR(report_rate, S_IWUSR | S_IRUGO, WORK_REGISTER_REPORT_RATE,
492 		NO_REGISTER, 0, 255);
493 
494 static struct attribute *edt_ft5x06_attrs[] = {
495 	&edt_ft5x06_attr_gain.dattr.attr,
496 	&edt_ft5x06_attr_offset.dattr.attr,
497 	&edt_ft5x06_attr_threshold.dattr.attr,
498 	&edt_ft5x06_attr_report_rate.dattr.attr,
499 	NULL
500 };
501 
502 static const struct attribute_group edt_ft5x06_attr_group = {
503 	.attrs = edt_ft5x06_attrs,
504 };
505 
506 #ifdef CONFIG_DEBUG_FS
507 static int edt_ft5x06_factory_mode(struct edt_ft5x06_ts_data *tsdata)
508 {
509 	struct i2c_client *client = tsdata->client;
510 	int retries = EDT_SWITCH_MODE_RETRIES;
511 	int ret;
512 	int error;
513 
514 	disable_irq(client->irq);
515 
516 	if (!tsdata->raw_buffer) {
517 		tsdata->raw_bufsize = tsdata->num_x * tsdata->num_y *
518 				      sizeof(u16);
519 		tsdata->raw_buffer = kzalloc(tsdata->raw_bufsize, GFP_KERNEL);
520 		if (!tsdata->raw_buffer) {
521 			error = -ENOMEM;
522 			goto err_out;
523 		}
524 	}
525 
526 	/* mode register is 0x3c when in the work mode */
527 	if (tsdata->version != EDT_M06)
528 		goto m09_out;
529 
530 	error = edt_ft5x06_register_write(tsdata, WORK_REGISTER_OPMODE, 0x03);
531 	if (error) {
532 		dev_err(&client->dev,
533 			"failed to switch to factory mode, error %d\n", error);
534 		goto err_out;
535 	}
536 
537 	tsdata->factory_mode = true;
538 	do {
539 		mdelay(EDT_SWITCH_MODE_DELAY);
540 		/* mode register is 0x01 when in factory mode */
541 		ret = edt_ft5x06_register_read(tsdata, FACTORY_REGISTER_OPMODE);
542 		if (ret == 0x03)
543 			break;
544 	} while (--retries > 0);
545 
546 	if (retries == 0) {
547 		dev_err(&client->dev, "not in factory mode after %dms.\n",
548 			EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
549 		error = -EIO;
550 		goto err_out;
551 	}
552 
553 	return 0;
554 
555 err_out:
556 	kfree(tsdata->raw_buffer);
557 	tsdata->raw_buffer = NULL;
558 	tsdata->factory_mode = false;
559 	enable_irq(client->irq);
560 
561 	return error;
562 
563 m09_out:
564 	dev_err(&client->dev, "No factory mode support for M09/M12/GENERIC_FT\n");
565 	return -EINVAL;
566 
567 }
568 
569 static int edt_ft5x06_work_mode(struct edt_ft5x06_ts_data *tsdata)
570 {
571 	struct i2c_client *client = tsdata->client;
572 	int retries = EDT_SWITCH_MODE_RETRIES;
573 	struct edt_reg_addr *reg_addr = &tsdata->reg_addr;
574 	int ret;
575 	int error;
576 
577 	/* mode register is 0x01 when in the factory mode */
578 	error = edt_ft5x06_register_write(tsdata, FACTORY_REGISTER_OPMODE, 0x1);
579 	if (error) {
580 		dev_err(&client->dev,
581 			"failed to switch to work mode, error: %d\n", error);
582 		return error;
583 	}
584 
585 	tsdata->factory_mode = false;
586 
587 	do {
588 		mdelay(EDT_SWITCH_MODE_DELAY);
589 		/* mode register is 0x01 when in factory mode */
590 		ret = edt_ft5x06_register_read(tsdata, WORK_REGISTER_OPMODE);
591 		if (ret == 0x01)
592 			break;
593 	} while (--retries > 0);
594 
595 	if (retries == 0) {
596 		dev_err(&client->dev, "not in work mode after %dms.\n",
597 			EDT_SWITCH_MODE_RETRIES * EDT_SWITCH_MODE_DELAY);
598 		tsdata->factory_mode = true;
599 		return -EIO;
600 	}
601 
602 	kfree(tsdata->raw_buffer);
603 	tsdata->raw_buffer = NULL;
604 
605 	/* restore parameters */
606 	edt_ft5x06_register_write(tsdata, reg_addr->reg_threshold,
607 				  tsdata->threshold);
608 	edt_ft5x06_register_write(tsdata, reg_addr->reg_gain,
609 				  tsdata->gain);
610 	edt_ft5x06_register_write(tsdata, reg_addr->reg_offset,
611 				  tsdata->offset);
612 	if (reg_addr->reg_report_rate != NO_REGISTER)
613 		edt_ft5x06_register_write(tsdata, reg_addr->reg_report_rate,
614 				  tsdata->report_rate);
615 
616 	enable_irq(client->irq);
617 
618 	return 0;
619 }
620 
621 static int edt_ft5x06_debugfs_mode_get(void *data, u64 *mode)
622 {
623 	struct edt_ft5x06_ts_data *tsdata = data;
624 
625 	*mode = tsdata->factory_mode;
626 
627 	return 0;
628 };
629 
630 static int edt_ft5x06_debugfs_mode_set(void *data, u64 mode)
631 {
632 	struct edt_ft5x06_ts_data *tsdata = data;
633 	int retval = 0;
634 
635 	if (mode > 1)
636 		return -ERANGE;
637 
638 	mutex_lock(&tsdata->mutex);
639 
640 	if (mode != tsdata->factory_mode) {
641 		retval = mode ? edt_ft5x06_factory_mode(tsdata) :
642 				edt_ft5x06_work_mode(tsdata);
643 	}
644 
645 	mutex_unlock(&tsdata->mutex);
646 
647 	return retval;
648 };
649 
650 DEFINE_SIMPLE_ATTRIBUTE(debugfs_mode_fops, edt_ft5x06_debugfs_mode_get,
651 			edt_ft5x06_debugfs_mode_set, "%llu\n");
652 
653 static ssize_t edt_ft5x06_debugfs_raw_data_read(struct file *file,
654 				char __user *buf, size_t count, loff_t *off)
655 {
656 	struct edt_ft5x06_ts_data *tsdata = file->private_data;
657 	struct i2c_client *client = tsdata->client;
658 	int retries  = EDT_RAW_DATA_RETRIES;
659 	int val, i, error;
660 	size_t read = 0;
661 	int colbytes;
662 	char wrbuf[3];
663 	u8 *rdbuf;
664 
665 	if (*off < 0 || *off >= tsdata->raw_bufsize)
666 		return 0;
667 
668 	mutex_lock(&tsdata->mutex);
669 
670 	if (!tsdata->factory_mode || !tsdata->raw_buffer) {
671 		error = -EIO;
672 		goto out;
673 	}
674 
675 	error = edt_ft5x06_register_write(tsdata, 0x08, 0x01);
676 	if (error) {
677 		dev_dbg(&client->dev,
678 			"failed to write 0x08 register, error %d\n", error);
679 		goto out;
680 	}
681 
682 	do {
683 		usleep_range(EDT_RAW_DATA_DELAY, EDT_RAW_DATA_DELAY + 100);
684 		val = edt_ft5x06_register_read(tsdata, 0x08);
685 		if (val < 1)
686 			break;
687 	} while (--retries > 0);
688 
689 	if (val < 0) {
690 		error = val;
691 		dev_dbg(&client->dev,
692 			"failed to read 0x08 register, error %d\n", error);
693 		goto out;
694 	}
695 
696 	if (retries == 0) {
697 		dev_dbg(&client->dev,
698 			"timed out waiting for register to settle\n");
699 		error = -ETIMEDOUT;
700 		goto out;
701 	}
702 
703 	rdbuf = tsdata->raw_buffer;
704 	colbytes = tsdata->num_y * sizeof(u16);
705 
706 	wrbuf[0] = 0xf5;
707 	wrbuf[1] = 0x0e;
708 	for (i = 0; i < tsdata->num_x; i++) {
709 		wrbuf[2] = i;  /* column index */
710 		error = edt_ft5x06_ts_readwrite(tsdata->client,
711 						sizeof(wrbuf), wrbuf,
712 						colbytes, rdbuf);
713 		if (error)
714 			goto out;
715 
716 		rdbuf += colbytes;
717 	}
718 
719 	read = min_t(size_t, count, tsdata->raw_bufsize - *off);
720 	if (copy_to_user(buf, tsdata->raw_buffer + *off, read)) {
721 		error = -EFAULT;
722 		goto out;
723 	}
724 
725 	*off += read;
726 out:
727 	mutex_unlock(&tsdata->mutex);
728 	return error ?: read;
729 };
730 
731 static const struct file_operations debugfs_raw_data_fops = {
732 	.open = simple_open,
733 	.read = edt_ft5x06_debugfs_raw_data_read,
734 };
735 
736 static void
737 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
738 			      const char *debugfs_name)
739 {
740 	tsdata->debug_dir = debugfs_create_dir(debugfs_name, NULL);
741 	if (!tsdata->debug_dir)
742 		return;
743 
744 	debugfs_create_u16("num_x", S_IRUSR, tsdata->debug_dir, &tsdata->num_x);
745 	debugfs_create_u16("num_y", S_IRUSR, tsdata->debug_dir, &tsdata->num_y);
746 
747 	debugfs_create_file("mode", S_IRUSR | S_IWUSR,
748 			    tsdata->debug_dir, tsdata, &debugfs_mode_fops);
749 	debugfs_create_file("raw_data", S_IRUSR,
750 			    tsdata->debug_dir, tsdata, &debugfs_raw_data_fops);
751 }
752 
753 static void
754 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
755 {
756 	debugfs_remove_recursive(tsdata->debug_dir);
757 	kfree(tsdata->raw_buffer);
758 }
759 
760 #else
761 
762 static inline void
763 edt_ft5x06_ts_prepare_debugfs(struct edt_ft5x06_ts_data *tsdata,
764 			      const char *debugfs_name)
765 {
766 }
767 
768 static inline void
769 edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata)
770 {
771 }
772 
773 #endif /* CONFIG_DEBUGFS */
774 
775 static int edt_ft5x06_ts_identify(struct i2c_client *client,
776 					struct edt_ft5x06_ts_data *tsdata,
777 					char *fw_version)
778 {
779 	u8 rdbuf[EDT_NAME_LEN];
780 	char *p;
781 	int error;
782 	char *model_name = tsdata->name;
783 
784 	/* see what we find if we assume it is a M06 *
785 	 * if we get less than EDT_NAME_LEN, we don't want
786 	 * to have garbage in there
787 	 */
788 	memset(rdbuf, 0, sizeof(rdbuf));
789 	error = edt_ft5x06_ts_readwrite(client, 1, "\xBB",
790 					EDT_NAME_LEN - 1, rdbuf);
791 	if (error)
792 		return error;
793 
794 	/* Probe content for something consistent.
795 	 * M06 starts with a response byte, M12 gives the data directly.
796 	 * M09/Generic does not provide model number information.
797 	 */
798 	if (!strncasecmp(rdbuf + 1, "EP0", 3)) {
799 		tsdata->version = EDT_M06;
800 
801 		/* remove last '$' end marker */
802 		rdbuf[EDT_NAME_LEN - 1] = '\0';
803 		if (rdbuf[EDT_NAME_LEN - 2] == '$')
804 			rdbuf[EDT_NAME_LEN - 2] = '\0';
805 
806 		/* look for Model/Version separator */
807 		p = strchr(rdbuf, '*');
808 		if (p)
809 			*p++ = '\0';
810 		strlcpy(model_name, rdbuf + 1, EDT_NAME_LEN);
811 		strlcpy(fw_version, p ? p : "", EDT_NAME_LEN);
812 	} else if (!strncasecmp(rdbuf, "EP0", 3)) {
813 		tsdata->version = EDT_M12;
814 
815 		/* remove last '$' end marker */
816 		rdbuf[EDT_NAME_LEN - 2] = '\0';
817 		if (rdbuf[EDT_NAME_LEN - 3] == '$')
818 			rdbuf[EDT_NAME_LEN - 3] = '\0';
819 
820 		/* look for Model/Version separator */
821 		p = strchr(rdbuf, '*');
822 		if (p)
823 			*p++ = '\0';
824 		strlcpy(model_name, rdbuf, EDT_NAME_LEN);
825 		strlcpy(fw_version, p ? p : "", EDT_NAME_LEN);
826 	} else {
827 		/* If it is not an EDT M06/M12 touchscreen, then the model
828 		 * detection is a bit hairy. The different ft5x06
829 		 * firmares around don't reliably implement the
830 		 * identification registers. Well, we'll take a shot.
831 		 *
832 		 * The main difference between generic focaltec based
833 		 * touches and EDT M09 is that we know how to retrieve
834 		 * the max coordinates for the latter.
835 		 */
836 		tsdata->version = GENERIC_FT;
837 
838 		error = edt_ft5x06_ts_readwrite(client, 1, "\xA6",
839 						2, rdbuf);
840 		if (error)
841 			return error;
842 
843 		strlcpy(fw_version, rdbuf, 2);
844 
845 		error = edt_ft5x06_ts_readwrite(client, 1, "\xA8",
846 						1, rdbuf);
847 		if (error)
848 			return error;
849 
850 		/* This "model identification" is not exact. Unfortunately
851 		 * not all firmwares for the ft5x06 put useful values in
852 		 * the identification registers.
853 		 */
854 		switch (rdbuf[0]) {
855 		case 0x35:   /* EDT EP0350M09 */
856 		case 0x43:   /* EDT EP0430M09 */
857 		case 0x50:   /* EDT EP0500M09 */
858 		case 0x57:   /* EDT EP0570M09 */
859 		case 0x70:   /* EDT EP0700M09 */
860 			tsdata->version = EDT_M09;
861 			snprintf(model_name, EDT_NAME_LEN, "EP0%i%i0M09",
862 				rdbuf[0] >> 4, rdbuf[0] & 0x0F);
863 			break;
864 		case 0xa1:   /* EDT EP1010ML00 */
865 			tsdata->version = EDT_M09;
866 			snprintf(model_name, EDT_NAME_LEN, "EP%i%i0ML00",
867 				rdbuf[0] >> 4, rdbuf[0] & 0x0F);
868 			break;
869 		case 0x5a:   /* Solomon Goldentek Display */
870 			snprintf(model_name, EDT_NAME_LEN, "GKTW50SCED1R0");
871 			break;
872 		default:
873 			snprintf(model_name, EDT_NAME_LEN,
874 				 "generic ft5x06 (%02x)",
875 				 rdbuf[0]);
876 			break;
877 		}
878 	}
879 
880 	return 0;
881 }
882 
883 static void edt_ft5x06_ts_get_defaults(struct device *dev,
884 				       struct edt_ft5x06_ts_data *tsdata)
885 {
886 	struct edt_reg_addr *reg_addr = &tsdata->reg_addr;
887 	u32 val;
888 	int error;
889 
890 	error = device_property_read_u32(dev, "threshold", &val);
891 	if (!error) {
892 		edt_ft5x06_register_write(tsdata, reg_addr->reg_threshold, val);
893 		tsdata->threshold = val;
894 	}
895 
896 	error = device_property_read_u32(dev, "gain", &val);
897 	if (!error) {
898 		edt_ft5x06_register_write(tsdata, reg_addr->reg_gain, val);
899 		tsdata->gain = val;
900 	}
901 
902 	error = device_property_read_u32(dev, "offset", &val);
903 	if (!error) {
904 		edt_ft5x06_register_write(tsdata, reg_addr->reg_offset, val);
905 		tsdata->offset = val;
906 	}
907 }
908 
909 static void
910 edt_ft5x06_ts_get_parameters(struct edt_ft5x06_ts_data *tsdata)
911 {
912 	struct edt_reg_addr *reg_addr = &tsdata->reg_addr;
913 
914 	tsdata->threshold = edt_ft5x06_register_read(tsdata,
915 						     reg_addr->reg_threshold);
916 	tsdata->gain = edt_ft5x06_register_read(tsdata, reg_addr->reg_gain);
917 	tsdata->offset = edt_ft5x06_register_read(tsdata, reg_addr->reg_offset);
918 	if (reg_addr->reg_report_rate != NO_REGISTER)
919 		tsdata->report_rate = edt_ft5x06_register_read(tsdata,
920 						reg_addr->reg_report_rate);
921 	if (tsdata->version == EDT_M06 ||
922 	    tsdata->version == EDT_M09 ||
923 	    tsdata->version == EDT_M12) {
924 		tsdata->num_x = edt_ft5x06_register_read(tsdata,
925 							 reg_addr->reg_num_x);
926 		tsdata->num_y = edt_ft5x06_register_read(tsdata,
927 							 reg_addr->reg_num_y);
928 	} else {
929 		tsdata->num_x = -1;
930 		tsdata->num_y = -1;
931 	}
932 }
933 
934 static void
935 edt_ft5x06_ts_set_regs(struct edt_ft5x06_ts_data *tsdata)
936 {
937 	struct edt_reg_addr *reg_addr = &tsdata->reg_addr;
938 
939 	switch (tsdata->version) {
940 	case EDT_M06:
941 		reg_addr->reg_threshold = WORK_REGISTER_THRESHOLD;
942 		reg_addr->reg_report_rate = WORK_REGISTER_REPORT_RATE;
943 		reg_addr->reg_gain = WORK_REGISTER_GAIN;
944 		reg_addr->reg_offset = WORK_REGISTER_OFFSET;
945 		reg_addr->reg_num_x = WORK_REGISTER_NUM_X;
946 		reg_addr->reg_num_y = WORK_REGISTER_NUM_Y;
947 		break;
948 
949 	case EDT_M09:
950 	case EDT_M12:
951 		reg_addr->reg_threshold = M09_REGISTER_THRESHOLD;
952 		reg_addr->reg_report_rate = NO_REGISTER;
953 		reg_addr->reg_gain = M09_REGISTER_GAIN;
954 		reg_addr->reg_offset = M09_REGISTER_OFFSET;
955 		reg_addr->reg_num_x = M09_REGISTER_NUM_X;
956 		reg_addr->reg_num_y = M09_REGISTER_NUM_Y;
957 		break;
958 
959 	case GENERIC_FT:
960 		/* this is a guesswork */
961 		reg_addr->reg_threshold = M09_REGISTER_THRESHOLD;
962 		reg_addr->reg_gain = M09_REGISTER_GAIN;
963 		reg_addr->reg_offset = M09_REGISTER_OFFSET;
964 		break;
965 	}
966 }
967 
968 static int edt_ft5x06_ts_probe(struct i2c_client *client,
969 					 const struct i2c_device_id *id)
970 {
971 	const struct edt_i2c_chip_data *chip_data;
972 	struct edt_ft5x06_ts_data *tsdata;
973 	struct input_dev *input;
974 	unsigned long irq_flags;
975 	int error;
976 	char fw_version[EDT_NAME_LEN];
977 
978 	dev_dbg(&client->dev, "probing for EDT FT5x06 I2C\n");
979 
980 	tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL);
981 	if (!tsdata) {
982 		dev_err(&client->dev, "failed to allocate driver data.\n");
983 		return -ENOMEM;
984 	}
985 
986 	chip_data = of_device_get_match_data(&client->dev);
987 	if (!chip_data)
988 		chip_data = (const struct edt_i2c_chip_data *)id->driver_data;
989 	if (!chip_data || !chip_data->max_support_points) {
990 		dev_err(&client->dev, "invalid or missing chip data\n");
991 		return -EINVAL;
992 	}
993 
994 	tsdata->max_support_points = chip_data->max_support_points;
995 
996 	tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev,
997 						     "reset", GPIOD_OUT_HIGH);
998 	if (IS_ERR(tsdata->reset_gpio)) {
999 		error = PTR_ERR(tsdata->reset_gpio);
1000 		dev_err(&client->dev,
1001 			"Failed to request GPIO reset pin, error %d\n", error);
1002 		return error;
1003 	}
1004 
1005 	tsdata->wake_gpio = devm_gpiod_get_optional(&client->dev,
1006 						    "wake", GPIOD_OUT_LOW);
1007 	if (IS_ERR(tsdata->wake_gpio)) {
1008 		error = PTR_ERR(tsdata->wake_gpio);
1009 		dev_err(&client->dev,
1010 			"Failed to request GPIO wake pin, error %d\n", error);
1011 		return error;
1012 	}
1013 
1014 	if (tsdata->wake_gpio) {
1015 		usleep_range(5000, 6000);
1016 		gpiod_set_value_cansleep(tsdata->wake_gpio, 1);
1017 	}
1018 
1019 	if (tsdata->reset_gpio) {
1020 		usleep_range(5000, 6000);
1021 		gpiod_set_value_cansleep(tsdata->reset_gpio, 0);
1022 		msleep(300);
1023 	}
1024 
1025 	input = devm_input_allocate_device(&client->dev);
1026 	if (!input) {
1027 		dev_err(&client->dev, "failed to allocate input device.\n");
1028 		return -ENOMEM;
1029 	}
1030 
1031 	mutex_init(&tsdata->mutex);
1032 	tsdata->client = client;
1033 	tsdata->input = input;
1034 	tsdata->factory_mode = false;
1035 
1036 	error = edt_ft5x06_ts_identify(client, tsdata, fw_version);
1037 	if (error) {
1038 		dev_err(&client->dev, "touchscreen probe failed\n");
1039 		return error;
1040 	}
1041 
1042 	edt_ft5x06_ts_set_regs(tsdata);
1043 	edt_ft5x06_ts_get_defaults(&client->dev, tsdata);
1044 	edt_ft5x06_ts_get_parameters(tsdata);
1045 
1046 	dev_dbg(&client->dev,
1047 		"Model \"%s\", Rev. \"%s\", %dx%d sensors\n",
1048 		tsdata->name, fw_version, tsdata->num_x, tsdata->num_y);
1049 
1050 	input->name = tsdata->name;
1051 	input->id.bustype = BUS_I2C;
1052 	input->dev.parent = &client->dev;
1053 
1054 	if (tsdata->version == EDT_M06 ||
1055 	    tsdata->version == EDT_M09 ||
1056 	    tsdata->version == EDT_M12) {
1057 		input_set_abs_params(input, ABS_MT_POSITION_X,
1058 				     0, tsdata->num_x * 64 - 1, 0, 0);
1059 		input_set_abs_params(input, ABS_MT_POSITION_Y,
1060 				     0, tsdata->num_y * 64 - 1, 0, 0);
1061 	} else {
1062 		/* Unknown maximum values. Specify via devicetree */
1063 		input_set_abs_params(input, ABS_MT_POSITION_X,
1064 				     0, 65535, 0, 0);
1065 		input_set_abs_params(input, ABS_MT_POSITION_Y,
1066 				     0, 65535, 0, 0);
1067 	}
1068 
1069 	touchscreen_parse_properties(input, true, &tsdata->prop);
1070 
1071 	error = input_mt_init_slots(input, tsdata->max_support_points,
1072 				INPUT_MT_DIRECT);
1073 	if (error) {
1074 		dev_err(&client->dev, "Unable to init MT slots.\n");
1075 		return error;
1076 	}
1077 
1078 	i2c_set_clientdata(client, tsdata);
1079 
1080 	irq_flags = irq_get_trigger_type(client->irq);
1081 	if (irq_flags == IRQF_TRIGGER_NONE)
1082 		irq_flags = IRQF_TRIGGER_FALLING;
1083 	irq_flags |= IRQF_ONESHOT;
1084 
1085 	error = devm_request_threaded_irq(&client->dev, client->irq,
1086 					NULL, edt_ft5x06_ts_isr, irq_flags,
1087 					client->name, tsdata);
1088 	if (error) {
1089 		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
1090 		return error;
1091 	}
1092 
1093 	error = devm_device_add_group(&client->dev, &edt_ft5x06_attr_group);
1094 	if (error)
1095 		return error;
1096 
1097 	error = input_register_device(input);
1098 	if (error)
1099 		return error;
1100 
1101 	edt_ft5x06_ts_prepare_debugfs(tsdata, dev_driver_string(&client->dev));
1102 	device_init_wakeup(&client->dev, 1);
1103 
1104 	dev_dbg(&client->dev,
1105 		"EDT FT5x06 initialized: IRQ %d, WAKE pin %d, Reset pin %d.\n",
1106 		client->irq,
1107 		tsdata->wake_gpio ? desc_to_gpio(tsdata->wake_gpio) : -1,
1108 		tsdata->reset_gpio ? desc_to_gpio(tsdata->reset_gpio) : -1);
1109 
1110 	return 0;
1111 }
1112 
1113 static int edt_ft5x06_ts_remove(struct i2c_client *client)
1114 {
1115 	struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
1116 
1117 	edt_ft5x06_ts_teardown_debugfs(tsdata);
1118 
1119 	return 0;
1120 }
1121 
1122 static int __maybe_unused edt_ft5x06_ts_suspend(struct device *dev)
1123 {
1124 	struct i2c_client *client = to_i2c_client(dev);
1125 
1126 	if (device_may_wakeup(dev))
1127 		enable_irq_wake(client->irq);
1128 
1129 	return 0;
1130 }
1131 
1132 static int __maybe_unused edt_ft5x06_ts_resume(struct device *dev)
1133 {
1134 	struct i2c_client *client = to_i2c_client(dev);
1135 
1136 	if (device_may_wakeup(dev))
1137 		disable_irq_wake(client->irq);
1138 
1139 	return 0;
1140 }
1141 
1142 static SIMPLE_DEV_PM_OPS(edt_ft5x06_ts_pm_ops,
1143 			 edt_ft5x06_ts_suspend, edt_ft5x06_ts_resume);
1144 
1145 static const struct edt_i2c_chip_data edt_ft5x06_data = {
1146 	.max_support_points = 5,
1147 };
1148 
1149 static const struct edt_i2c_chip_data edt_ft5506_data = {
1150 	.max_support_points = 10,
1151 };
1152 
1153 static const struct edt_i2c_chip_data edt_ft6236_data = {
1154 	.max_support_points = 2,
1155 };
1156 
1157 static const struct i2c_device_id edt_ft5x06_ts_id[] = {
1158 	{ .name = "edt-ft5x06", .driver_data = (long)&edt_ft5x06_data },
1159 	{ .name = "edt-ft5506", .driver_data = (long)&edt_ft5506_data },
1160 	/* Note no edt- prefix for compatibility with the ft6236.c driver */
1161 	{ .name = "ft6236", .driver_data = (long)&edt_ft6236_data },
1162 	{ /* sentinel */ }
1163 };
1164 MODULE_DEVICE_TABLE(i2c, edt_ft5x06_ts_id);
1165 
1166 #ifdef CONFIG_OF
1167 static const struct of_device_id edt_ft5x06_of_match[] = {
1168 	{ .compatible = "edt,edt-ft5206", .data = &edt_ft5x06_data },
1169 	{ .compatible = "edt,edt-ft5306", .data = &edt_ft5x06_data },
1170 	{ .compatible = "edt,edt-ft5406", .data = &edt_ft5x06_data },
1171 	{ .compatible = "edt,edt-ft5506", .data = &edt_ft5506_data },
1172 	/* Note focaltech vendor prefix for compatibility with ft6236.c */
1173 	{ .compatible = "focaltech,ft6236", .data = &edt_ft6236_data },
1174 	{ /* sentinel */ }
1175 };
1176 MODULE_DEVICE_TABLE(of, edt_ft5x06_of_match);
1177 #endif
1178 
1179 static struct i2c_driver edt_ft5x06_ts_driver = {
1180 	.driver = {
1181 		.name = "edt_ft5x06",
1182 		.of_match_table = of_match_ptr(edt_ft5x06_of_match),
1183 		.pm = &edt_ft5x06_ts_pm_ops,
1184 	},
1185 	.id_table = edt_ft5x06_ts_id,
1186 	.probe    = edt_ft5x06_ts_probe,
1187 	.remove   = edt_ft5x06_ts_remove,
1188 };
1189 
1190 module_i2c_driver(edt_ft5x06_ts_driver);
1191 
1192 MODULE_AUTHOR("Simon Budig <simon.budig@kernelconcepts.de>");
1193 MODULE_DESCRIPTION("EDT FT5x06 I2C Touchscreen Driver");
1194 MODULE_LICENSE("GPL");
1195