1 /*
2  * Elan I2C/SMBus Touchpad driver
3  *
4  * Copyright (c) 2013 ELAN Microelectronics Corp.
5  *
6  * Author: 林政維 (Duson Lin) <dusonlin@emc.com.tw>
7  * Version: 1.5.5
8  *
9  * Based on cyapa driver:
10  * copyright (c) 2011-2012 Cypress Semiconductor, Inc.
11  * copyright (c) 2011-2012 Google, Inc.
12  *
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms of the GNU General Public License version 2 as published
15  * by the Free Software Foundation.
16  *
17  * Trademarks are the property of their respective owners.
18  */
19 
20 #include <linux/acpi.h>
21 #include <linux/delay.h>
22 #include <linux/device.h>
23 #include <linux/firmware.h>
24 #include <linux/i2c.h>
25 #include <linux/init.h>
26 #include <linux/input/mt.h>
27 #include <linux/interrupt.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/input.h>
33 #include <linux/uaccess.h>
34 #include <linux/jiffies.h>
35 #include <linux/completion.h>
36 #include <linux/of.h>
37 #include <linux/regulator/consumer.h>
38 #include <asm/unaligned.h>
39 
40 #include "elan_i2c.h"
41 
42 #define DRIVER_NAME		"elan_i2c"
43 #define ELAN_DRIVER_VERSION	"1.5.5"
44 #define ETP_PRESSURE_OFFSET	25
45 #define ETP_MAX_PRESSURE	255
46 #define ETP_FWIDTH_REDUCE	90
47 #define ETP_FINGER_WIDTH	15
48 #define ETP_RETRY_COUNT		3
49 
50 #define ETP_MAX_FINGERS		5
51 #define ETP_FINGER_DATA_LEN	5
52 #define ETP_REPORT_ID		0x5D
53 #define ETP_REPORT_ID_OFFSET	2
54 #define ETP_TOUCH_INFO_OFFSET	3
55 #define ETP_FINGER_DATA_OFFSET	4
56 #define ETP_MAX_REPORT_LEN	34
57 
58 /* The main device structure */
59 struct elan_tp_data {
60 	struct i2c_client	*client;
61 	struct input_dev	*input;
62 	struct regulator	*vcc;
63 
64 	const struct elan_transport_ops *ops;
65 
66 	/* for fw update */
67 	struct completion	fw_completion;
68 	bool			in_fw_update;
69 
70 	struct mutex		sysfs_mutex;
71 
72 	unsigned int		max_x;
73 	unsigned int		max_y;
74 	unsigned int		width_x;
75 	unsigned int		width_y;
76 	unsigned int		x_res;
77 	unsigned int		y_res;
78 
79 	u8			product_id;
80 	u8			fw_version;
81 	u8			sm_version;
82 	u8			iap_version;
83 	u16			fw_checksum;
84 
85 	u8			mode;
86 
87 	bool			irq_wake;
88 
89 	u8			min_baseline;
90 	u8			max_baseline;
91 	bool			baseline_ready;
92 };
93 
94 static int elan_enable_power(struct elan_tp_data *data)
95 {
96 	int repeat = ETP_RETRY_COUNT;
97 	int error;
98 
99 	error = regulator_enable(data->vcc);
100 	if (error) {
101 		dev_err(&data->client->dev,
102 			"Failed to enable regulator: %d\n", error);
103 		return error;
104 	}
105 
106 	do {
107 		error = data->ops->power_control(data->client, true);
108 		if (error >= 0)
109 			return 0;
110 
111 		msleep(30);
112 	} while (--repeat > 0);
113 
114 	return error;
115 }
116 
117 static int elan_disable_power(struct elan_tp_data *data)
118 {
119 	int repeat = ETP_RETRY_COUNT;
120 	int error;
121 
122 	do {
123 		error = data->ops->power_control(data->client, false);
124 		if (!error) {
125 			error = regulator_disable(data->vcc);
126 			if (error) {
127 				dev_err(&data->client->dev,
128 					"Failed to disable regulator: %d\n",
129 					error);
130 				/* Attempt to power the chip back up */
131 				data->ops->power_control(data->client, true);
132 				break;
133 			}
134 
135 			return 0;
136 		}
137 
138 		msleep(30);
139 	} while (--repeat > 0);
140 
141 	return error;
142 }
143 
144 static int elan_sleep(struct elan_tp_data *data)
145 {
146 	int repeat = ETP_RETRY_COUNT;
147 	int error;
148 
149 	do {
150 		error = data->ops->sleep_control(data->client, true);
151 		if (!error)
152 			return 0;
153 
154 		msleep(30);
155 	} while (--repeat > 0);
156 
157 	return error;
158 }
159 
160 static int __elan_initialize(struct elan_tp_data *data)
161 {
162 	struct i2c_client *client = data->client;
163 	int error;
164 
165 	error = data->ops->initialize(client);
166 	if (error) {
167 		dev_err(&client->dev, "device initialize failed: %d\n", error);
168 		return error;
169 	}
170 
171 	data->mode |= ETP_ENABLE_ABS;
172 	error = data->ops->set_mode(client, data->mode);
173 	if (error) {
174 		dev_err(&client->dev,
175 			"failed to switch to absolute mode: %d\n", error);
176 		return error;
177 	}
178 
179 	error = data->ops->sleep_control(client, false);
180 	if (error) {
181 		dev_err(&client->dev,
182 			"failed to wake device up: %d\n", error);
183 		return error;
184 	}
185 
186 	return 0;
187 }
188 
189 static int elan_initialize(struct elan_tp_data *data)
190 {
191 	int repeat = ETP_RETRY_COUNT;
192 	int error;
193 
194 	do {
195 		error = __elan_initialize(data);
196 		if (!error)
197 			return 0;
198 
199 		repeat--;
200 		msleep(30);
201 	} while (--repeat > 0);
202 
203 	return error;
204 }
205 
206 static int elan_query_device_info(struct elan_tp_data *data)
207 {
208 	int error;
209 
210 	error = data->ops->get_product_id(data->client, &data->product_id);
211 	if (error)
212 		return error;
213 
214 	error = data->ops->get_version(data->client, false, &data->fw_version);
215 	if (error)
216 		return error;
217 
218 	error = data->ops->get_checksum(data->client, false,
219 					&data->fw_checksum);
220 	if (error)
221 		return error;
222 
223 	error = data->ops->get_sm_version(data->client, &data->sm_version);
224 	if (error)
225 		return error;
226 
227 	error = data->ops->get_version(data->client, true, &data->iap_version);
228 	if (error)
229 		return error;
230 
231 	return 0;
232 }
233 
234 static unsigned int elan_convert_resolution(u8 val)
235 {
236 	/*
237 	 * (value from firmware) * 10 + 790 = dpi
238 	 *
239 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
240 	 * point).
241 	 */
242 
243 	return ((int)(char)val * 10 + 790) * 10 / 254;
244 }
245 
246 static int elan_query_device_parameters(struct elan_tp_data *data)
247 {
248 	unsigned int x_traces, y_traces;
249 	u8 hw_x_res, hw_y_res;
250 	int error;
251 
252 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
253 	if (error)
254 		return error;
255 
256 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
257 	if (error)
258 		return error;
259 
260 	data->width_x = data->max_x / x_traces;
261 	data->width_y = data->max_y / y_traces;
262 
263 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
264 	if (error)
265 		return error;
266 
267 	data->x_res = elan_convert_resolution(hw_x_res);
268 	data->y_res = elan_convert_resolution(hw_y_res);
269 
270 	return 0;
271 }
272 
273 /*
274  **********************************************************
275  * IAP firmware updater related routines
276  **********************************************************
277  */
278 static int elan_write_fw_block(struct elan_tp_data *data,
279 			       const u8 *page, u16 checksum, int idx)
280 {
281 	int retry = ETP_RETRY_COUNT;
282 	int error;
283 
284 	do {
285 		error = data->ops->write_fw_block(data->client,
286 						  page, checksum, idx);
287 		if (!error)
288 			return 0;
289 
290 		dev_dbg(&data->client->dev,
291 			"IAP retrying page %d (error: %d)\n", idx, error);
292 	} while (--retry > 0);
293 
294 	return error;
295 }
296 
297 static int __elan_update_firmware(struct elan_tp_data *data,
298 				  const struct firmware *fw)
299 {
300 	struct i2c_client *client = data->client;
301 	struct device *dev = &client->dev;
302 	int i, j;
303 	int error;
304 	u16 iap_start_addr;
305 	u16 boot_page_count;
306 	u16 sw_checksum = 0, fw_checksum = 0;
307 
308 	error = data->ops->prepare_fw_update(client);
309 	if (error)
310 		return error;
311 
312 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
313 
314 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
315 	for (i = boot_page_count; i < ETP_FW_PAGE_COUNT; i++) {
316 		u16 checksum = 0;
317 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
318 
319 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
320 			checksum += ((page[j + 1] << 8) | page[j]);
321 
322 		error = elan_write_fw_block(data, page, checksum, i);
323 		if (error) {
324 			dev_err(dev, "write page %d fail: %d\n", i, error);
325 			return error;
326 		}
327 
328 		sw_checksum += checksum;
329 	}
330 
331 	/* Wait WDT reset and power on reset */
332 	msleep(600);
333 
334 	error = data->ops->finish_fw_update(client, &data->fw_completion);
335 	if (error)
336 		return error;
337 
338 	error = data->ops->get_checksum(client, true, &fw_checksum);
339 	if (error)
340 		return error;
341 
342 	if (sw_checksum != fw_checksum) {
343 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
344 			sw_checksum, fw_checksum);
345 		return -EIO;
346 	}
347 
348 	return 0;
349 }
350 
351 static int elan_update_firmware(struct elan_tp_data *data,
352 				const struct firmware *fw)
353 {
354 	struct i2c_client *client = data->client;
355 	int retval;
356 
357 	dev_dbg(&client->dev, "Starting firmware update....\n");
358 
359 	disable_irq(client->irq);
360 	data->in_fw_update = true;
361 
362 	retval = __elan_update_firmware(data, fw);
363 	if (retval) {
364 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
365 		data->ops->iap_reset(client);
366 	} else {
367 		/* Reinitialize TP after fw is updated */
368 		elan_initialize(data);
369 		elan_query_device_info(data);
370 	}
371 
372 	data->in_fw_update = false;
373 	enable_irq(client->irq);
374 
375 	return retval;
376 }
377 
378 /*
379  *******************************************************************
380  * SYSFS attributes
381  *******************************************************************
382  */
383 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
384 					   struct device_attribute *attr,
385 					   char *buf)
386 {
387 	struct i2c_client *client = to_i2c_client(dev);
388 	struct elan_tp_data *data = i2c_get_clientdata(client);
389 
390 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
391 }
392 
393 static ssize_t elan_sysfs_read_product_id(struct device *dev,
394 					 struct device_attribute *attr,
395 					 char *buf)
396 {
397 	struct i2c_client *client = to_i2c_client(dev);
398 	struct elan_tp_data *data = i2c_get_clientdata(client);
399 
400 	return sprintf(buf, "%d.0\n", data->product_id);
401 }
402 
403 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
404 				      struct device_attribute *attr,
405 				      char *buf)
406 {
407 	struct i2c_client *client = to_i2c_client(dev);
408 	struct elan_tp_data *data = i2c_get_clientdata(client);
409 
410 	return sprintf(buf, "%d.0\n", data->fw_version);
411 }
412 
413 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
414 				      struct device_attribute *attr,
415 				      char *buf)
416 {
417 	struct i2c_client *client = to_i2c_client(dev);
418 	struct elan_tp_data *data = i2c_get_clientdata(client);
419 
420 	return sprintf(buf, "%d.0\n", data->sm_version);
421 }
422 
423 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
424 				       struct device_attribute *attr,
425 				       char *buf)
426 {
427 	struct i2c_client *client = to_i2c_client(dev);
428 	struct elan_tp_data *data = i2c_get_clientdata(client);
429 
430 	return sprintf(buf, "%d.0\n", data->iap_version);
431 }
432 
433 static ssize_t elan_sysfs_update_fw(struct device *dev,
434 				    struct device_attribute *attr,
435 				    const char *buf, size_t count)
436 {
437 	struct i2c_client *client = to_i2c_client(dev);
438 	struct elan_tp_data *data = i2c_get_clientdata(client);
439 	const struct firmware *fw;
440 	int error;
441 
442 	error = request_firmware(&fw, ETP_FW_NAME, dev);
443 	if (error) {
444 		dev_err(dev, "cannot load firmware %s: %d\n",
445 			ETP_FW_NAME, error);
446 		return error;
447 	}
448 
449 	/* Firmware must be exactly PAGE_NUM * PAGE_SIZE bytes */
450 	if (fw->size != ETP_FW_SIZE) {
451 		dev_err(dev, "invalid firmware size = %zu, expected %d.\n",
452 			fw->size, ETP_FW_SIZE);
453 		error = -EBADF;
454 		goto out_release_fw;
455 	}
456 
457 	error = mutex_lock_interruptible(&data->sysfs_mutex);
458 	if (error)
459 		goto out_release_fw;
460 
461 	error = elan_update_firmware(data, fw);
462 
463 	mutex_unlock(&data->sysfs_mutex);
464 
465 out_release_fw:
466 	release_firmware(fw);
467 	return error ?: count;
468 }
469 
470 static ssize_t calibrate_store(struct device *dev,
471 			       struct device_attribute *attr,
472 			       const char *buf, size_t count)
473 {
474 	struct i2c_client *client = to_i2c_client(dev);
475 	struct elan_tp_data *data = i2c_get_clientdata(client);
476 	int tries = 20;
477 	int retval;
478 	int error;
479 	u8 val[3];
480 
481 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
482 	if (retval)
483 		return retval;
484 
485 	disable_irq(client->irq);
486 
487 	data->mode |= ETP_ENABLE_CALIBRATE;
488 	retval = data->ops->set_mode(client, data->mode);
489 	if (retval) {
490 		dev_err(dev, "failed to enable calibration mode: %d\n",
491 			retval);
492 		goto out;
493 	}
494 
495 	retval = data->ops->calibrate(client);
496 	if (retval) {
497 		dev_err(dev, "failed to start calibration: %d\n",
498 			retval);
499 		goto out_disable_calibrate;
500 	}
501 
502 	val[0] = 0xff;
503 	do {
504 		/* Wait 250ms before checking if calibration has completed. */
505 		msleep(250);
506 
507 		retval = data->ops->calibrate_result(client, val);
508 		if (retval)
509 			dev_err(dev, "failed to check calibration result: %d\n",
510 				retval);
511 		else if (val[0] == 0)
512 			break; /* calibration done */
513 
514 	} while (--tries);
515 
516 	if (tries == 0) {
517 		dev_err(dev, "failed to calibrate. Timeout.\n");
518 		retval = -ETIMEDOUT;
519 	}
520 
521 out_disable_calibrate:
522 	data->mode &= ~ETP_ENABLE_CALIBRATE;
523 	error = data->ops->set_mode(data->client, data->mode);
524 	if (error) {
525 		dev_err(dev, "failed to disable calibration mode: %d\n",
526 			error);
527 		if (!retval)
528 			retval = error;
529 	}
530 out:
531 	enable_irq(client->irq);
532 	mutex_unlock(&data->sysfs_mutex);
533 	return retval ?: count;
534 }
535 
536 static ssize_t elan_sysfs_read_mode(struct device *dev,
537 				    struct device_attribute *attr,
538 				    char *buf)
539 {
540 	struct i2c_client *client = to_i2c_client(dev);
541 	struct elan_tp_data *data = i2c_get_clientdata(client);
542 	int error;
543 	enum tp_mode mode;
544 
545 	error = mutex_lock_interruptible(&data->sysfs_mutex);
546 	if (error)
547 		return error;
548 
549 	error = data->ops->iap_get_mode(data->client, &mode);
550 
551 	mutex_unlock(&data->sysfs_mutex);
552 
553 	if (error)
554 		return error;
555 
556 	return sprintf(buf, "%d\n", (int)mode);
557 }
558 
559 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
560 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
561 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
562 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
563 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
564 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
565 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
566 
567 static DEVICE_ATTR_WO(calibrate);
568 
569 static struct attribute *elan_sysfs_entries[] = {
570 	&dev_attr_product_id.attr,
571 	&dev_attr_firmware_version.attr,
572 	&dev_attr_sample_version.attr,
573 	&dev_attr_iap_version.attr,
574 	&dev_attr_fw_checksum.attr,
575 	&dev_attr_calibrate.attr,
576 	&dev_attr_mode.attr,
577 	&dev_attr_update_fw.attr,
578 	NULL,
579 };
580 
581 static const struct attribute_group elan_sysfs_group = {
582 	.attrs = elan_sysfs_entries,
583 };
584 
585 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
586 			     const char *buf, size_t count)
587 {
588 	struct i2c_client *client = to_i2c_client(dev);
589 	struct elan_tp_data *data = i2c_get_clientdata(client);
590 	int error;
591 	int retval;
592 
593 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
594 	if (retval)
595 		return retval;
596 
597 	disable_irq(client->irq);
598 
599 	data->baseline_ready = false;
600 
601 	data->mode |= ETP_ENABLE_CALIBRATE;
602 	retval = data->ops->set_mode(data->client, data->mode);
603 	if (retval) {
604 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
605 			retval);
606 		goto out;
607 	}
608 
609 	msleep(250);
610 
611 	retval = data->ops->get_baseline_data(data->client, true,
612 					      &data->max_baseline);
613 	if (retval) {
614 		dev_err(dev, "Failed to read max baseline form device: %d\n",
615 			retval);
616 		goto out_disable_calibrate;
617 	}
618 
619 	retval = data->ops->get_baseline_data(data->client, false,
620 					      &data->min_baseline);
621 	if (retval) {
622 		dev_err(dev, "Failed to read min baseline form device: %d\n",
623 			retval);
624 		goto out_disable_calibrate;
625 	}
626 
627 	data->baseline_ready = true;
628 
629 out_disable_calibrate:
630 	data->mode &= ~ETP_ENABLE_CALIBRATE;
631 	error = data->ops->set_mode(data->client, data->mode);
632 	if (error) {
633 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
634 			error);
635 		if (!retval)
636 			retval = error;
637 	}
638 out:
639 	enable_irq(client->irq);
640 	mutex_unlock(&data->sysfs_mutex);
641 	return retval ?: count;
642 }
643 
644 static ssize_t min_show(struct device *dev,
645 			struct device_attribute *attr, char *buf)
646 {
647 	struct i2c_client *client = to_i2c_client(dev);
648 	struct elan_tp_data *data = i2c_get_clientdata(client);
649 	int retval;
650 
651 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
652 	if (retval)
653 		return retval;
654 
655 	if (!data->baseline_ready) {
656 		retval = -ENODATA;
657 		goto out;
658 	}
659 
660 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
661 
662 out:
663 	mutex_unlock(&data->sysfs_mutex);
664 	return retval;
665 }
666 
667 static ssize_t max_show(struct device *dev,
668 			struct device_attribute *attr, char *buf)
669 {
670 	struct i2c_client *client = to_i2c_client(dev);
671 	struct elan_tp_data *data = i2c_get_clientdata(client);
672 	int retval;
673 
674 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
675 	if (retval)
676 		return retval;
677 
678 	if (!data->baseline_ready) {
679 		retval = -ENODATA;
680 		goto out;
681 	}
682 
683 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
684 
685 out:
686 	mutex_unlock(&data->sysfs_mutex);
687 	return retval;
688 }
689 
690 
691 static DEVICE_ATTR_WO(acquire);
692 static DEVICE_ATTR_RO(min);
693 static DEVICE_ATTR_RO(max);
694 
695 static struct attribute *elan_baseline_sysfs_entries[] = {
696 	&dev_attr_acquire.attr,
697 	&dev_attr_min.attr,
698 	&dev_attr_max.attr,
699 	NULL,
700 };
701 
702 static const struct attribute_group elan_baseline_sysfs_group = {
703 	.name = "baseline",
704 	.attrs = elan_baseline_sysfs_entries,
705 };
706 
707 static const struct attribute_group *elan_sysfs_groups[] = {
708 	&elan_sysfs_group,
709 	&elan_baseline_sysfs_group,
710 	NULL
711 };
712 
713 /*
714  ******************************************************************
715  * Elan isr functions
716  ******************************************************************
717  */
718 static void elan_report_contact(struct elan_tp_data *data,
719 				int contact_num, bool contact_valid,
720 				u8 *finger_data)
721 {
722 	struct input_dev *input = data->input;
723 	unsigned int pos_x, pos_y;
724 	unsigned int pressure, mk_x, mk_y;
725 	unsigned int area_x, area_y, major, minor, new_pressure;
726 
727 
728 	if (contact_valid) {
729 		pos_x = ((finger_data[0] & 0xf0) << 4) |
730 						finger_data[1];
731 		pos_y = ((finger_data[0] & 0x0f) << 8) |
732 						finger_data[2];
733 		mk_x = (finger_data[3] & 0x0f);
734 		mk_y = (finger_data[3] >> 4);
735 		pressure = finger_data[4];
736 
737 		if (pos_x > data->max_x || pos_y > data->max_y) {
738 			dev_dbg(input->dev.parent,
739 				"[%d] x=%d y=%d over max (%d, %d)",
740 				contact_num, pos_x, pos_y,
741 				data->max_x, data->max_y);
742 			return;
743 		}
744 
745 		/*
746 		 * To avoid treating large finger as palm, let's reduce the
747 		 * width x and y per trace.
748 		 */
749 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
750 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
751 
752 		major = max(area_x, area_y);
753 		minor = min(area_x, area_y);
754 
755 		new_pressure = pressure + ETP_PRESSURE_OFFSET;
756 		if (new_pressure > ETP_MAX_PRESSURE)
757 			new_pressure = ETP_MAX_PRESSURE;
758 
759 		input_mt_slot(input, contact_num);
760 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
761 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
762 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
763 		input_report_abs(input, ABS_MT_PRESSURE, new_pressure);
764 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
765 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
766 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
767 	} else {
768 		input_mt_slot(input, contact_num);
769 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
770 	}
771 }
772 
773 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
774 {
775 	struct input_dev *input = data->input;
776 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
777 	int i;
778 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
779 	bool contact_valid;
780 
781 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
782 		contact_valid = tp_info & (1U << (3 + i));
783 		elan_report_contact(data, i, contact_valid, finger_data);
784 
785 		if (contact_valid)
786 			finger_data += ETP_FINGER_DATA_LEN;
787 	}
788 
789 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
790 	input_mt_report_pointer_emulation(input, true);
791 	input_sync(input);
792 }
793 
794 static irqreturn_t elan_isr(int irq, void *dev_id)
795 {
796 	struct elan_tp_data *data = dev_id;
797 	struct device *dev = &data->client->dev;
798 	int error;
799 	u8 report[ETP_MAX_REPORT_LEN];
800 
801 	/*
802 	 * When device is connected to i2c bus, when all IAP page writes
803 	 * complete, the driver will receive interrupt and must read
804 	 * 0000 to confirm that IAP is finished.
805 	*/
806 	if (data->in_fw_update) {
807 		complete(&data->fw_completion);
808 		goto out;
809 	}
810 
811 	error = data->ops->get_report(data->client, report);
812 	if (error)
813 		goto out;
814 
815 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
816 		dev_err(dev, "invalid report id data (%x)\n",
817 			report[ETP_REPORT_ID_OFFSET]);
818 	else
819 		elan_report_absolute(data, report);
820 
821 out:
822 	return IRQ_HANDLED;
823 }
824 
825 /*
826  ******************************************************************
827  * Elan initialization functions
828  ******************************************************************
829  */
830 static int elan_setup_input_device(struct elan_tp_data *data)
831 {
832 	struct device *dev = &data->client->dev;
833 	struct input_dev *input;
834 	unsigned int max_width = max(data->width_x, data->width_y);
835 	unsigned int min_width = min(data->width_x, data->width_y);
836 	int error;
837 
838 	input = devm_input_allocate_device(dev);
839 	if (!input)
840 		return -ENOMEM;
841 
842 	input->name = "Elan Touchpad";
843 	input->id.bustype = BUS_I2C;
844 	input_set_drvdata(input, data);
845 
846 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
847 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
848 	if (error) {
849 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
850 		return error;
851 	}
852 
853 	__set_bit(EV_ABS, input->evbit);
854 	__set_bit(INPUT_PROP_POINTER, input->propbit);
855 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
856 	__set_bit(BTN_LEFT, input->keybit);
857 
858 	/* Set up ST parameters */
859 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
860 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
861 	input_abs_set_res(input, ABS_X, data->x_res);
862 	input_abs_set_res(input, ABS_Y, data->y_res);
863 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
864 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
865 
866 	/* And MT parameters */
867 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
868 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
869 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
870 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
871 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
872 			     ETP_MAX_PRESSURE, 0, 0);
873 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
874 			     ETP_FINGER_WIDTH * max_width, 0, 0);
875 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
876 			     ETP_FINGER_WIDTH * min_width, 0, 0);
877 
878 	data->input = input;
879 
880 	return 0;
881 }
882 
883 static void elan_disable_regulator(void *_data)
884 {
885 	struct elan_tp_data *data = _data;
886 
887 	regulator_disable(data->vcc);
888 }
889 
890 static void elan_remove_sysfs_groups(void *_data)
891 {
892 	struct elan_tp_data *data = _data;
893 
894 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
895 }
896 
897 static int elan_probe(struct i2c_client *client,
898 		      const struct i2c_device_id *dev_id)
899 {
900 	const struct elan_transport_ops *transport_ops;
901 	struct device *dev = &client->dev;
902 	struct elan_tp_data *data;
903 	unsigned long irqflags;
904 	int error;
905 
906 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
907 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
908 		transport_ops = &elan_i2c_ops;
909 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
910 		   i2c_check_functionality(client->adapter,
911 					   I2C_FUNC_SMBUS_BYTE_DATA |
912 						I2C_FUNC_SMBUS_BLOCK_DATA |
913 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
914 		transport_ops = &elan_smbus_ops;
915 	} else {
916 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
917 		return -EIO;
918 	}
919 
920 	data = devm_kzalloc(&client->dev, sizeof(struct elan_tp_data),
921 			    GFP_KERNEL);
922 	if (!data)
923 		return -ENOMEM;
924 
925 	i2c_set_clientdata(client, data);
926 
927 	data->ops = transport_ops;
928 	data->client = client;
929 	init_completion(&data->fw_completion);
930 	mutex_init(&data->sysfs_mutex);
931 
932 	data->vcc = devm_regulator_get(&client->dev, "vcc");
933 	if (IS_ERR(data->vcc)) {
934 		error = PTR_ERR(data->vcc);
935 		if (error != -EPROBE_DEFER)
936 			dev_err(&client->dev,
937 				"Failed to get 'vcc' regulator: %d\n",
938 				error);
939 		return error;
940 	}
941 
942 	error = regulator_enable(data->vcc);
943 	if (error) {
944 		dev_err(&client->dev,
945 			"Failed to enable regulator: %d\n", error);
946 		return error;
947 	}
948 
949 	error = devm_add_action(&client->dev,
950 				elan_disable_regulator, data);
951 	if (error) {
952 		regulator_disable(data->vcc);
953 		dev_err(&client->dev,
954 			"Failed to add disable regulator action: %d\n",
955 			error);
956 		return error;
957 	}
958 
959 	/* Initialize the touchpad. */
960 	error = elan_initialize(data);
961 	if (error)
962 		return error;
963 
964 	error = elan_query_device_info(data);
965 	if (error)
966 		return error;
967 
968 	error = elan_query_device_parameters(data);
969 	if (error)
970 		return error;
971 
972 	dev_dbg(&client->dev,
973 		"Elan Touchpad Information:\n"
974 		"    Module product ID:  0x%04x\n"
975 		"    Firmware Version:  0x%04x\n"
976 		"    Sample Version:  0x%04x\n"
977 		"    IAP Version:  0x%04x\n"
978 		"    Max ABS X,Y:   %d,%d\n"
979 		"    Width X,Y:   %d,%d\n"
980 		"    Resolution X,Y:   %d,%d (dots/mm)\n",
981 		data->product_id,
982 		data->fw_version,
983 		data->sm_version,
984 		data->iap_version,
985 		data->max_x, data->max_y,
986 		data->width_x, data->width_y,
987 		data->x_res, data->y_res);
988 
989 	/* Set up input device properties based on queried parameters. */
990 	error = elan_setup_input_device(data);
991 	if (error)
992 		return error;
993 
994 	/*
995 	 * Systems using device tree should set up interrupt via DTS,
996 	 * the rest will use the default falling edge interrupts.
997 	 */
998 	irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
999 
1000 	error = devm_request_threaded_irq(&client->dev, client->irq,
1001 					  NULL, elan_isr,
1002 					  irqflags | IRQF_ONESHOT,
1003 					  client->name, data);
1004 	if (error) {
1005 		dev_err(&client->dev, "cannot register irq=%d\n", client->irq);
1006 		return error;
1007 	}
1008 
1009 	error = sysfs_create_groups(&client->dev.kobj, elan_sysfs_groups);
1010 	if (error) {
1011 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1012 			error);
1013 		return error;
1014 	}
1015 
1016 	error = devm_add_action(&client->dev,
1017 				elan_remove_sysfs_groups, data);
1018 	if (error) {
1019 		elan_remove_sysfs_groups(data);
1020 		dev_err(&client->dev,
1021 			"Failed to add sysfs cleanup action: %d\n",
1022 			error);
1023 		return error;
1024 	}
1025 
1026 	error = input_register_device(data->input);
1027 	if (error) {
1028 		dev_err(&client->dev, "failed to register input device: %d\n",
1029 			error);
1030 		return error;
1031 	}
1032 
1033 	/*
1034 	 * Systems using device tree should set up wakeup via DTS,
1035 	 * the rest will configure device as wakeup source by default.
1036 	 */
1037 	if (!client->dev.of_node)
1038 		device_init_wakeup(&client->dev, true);
1039 
1040 	return 0;
1041 }
1042 
1043 static int __maybe_unused elan_suspend(struct device *dev)
1044 {
1045 	struct i2c_client *client = to_i2c_client(dev);
1046 	struct elan_tp_data *data = i2c_get_clientdata(client);
1047 	int ret;
1048 
1049 	/*
1050 	 * We are taking the mutex to make sure sysfs operations are
1051 	 * complete before we attempt to bring the device into low[er]
1052 	 * power mode.
1053 	 */
1054 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1055 	if (ret)
1056 		return ret;
1057 
1058 	disable_irq(client->irq);
1059 
1060 	if (device_may_wakeup(dev)) {
1061 		ret = elan_sleep(data);
1062 		/* Enable wake from IRQ */
1063 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1064 	} else {
1065 		ret = elan_disable_power(data);
1066 	}
1067 
1068 	mutex_unlock(&data->sysfs_mutex);
1069 	return ret;
1070 }
1071 
1072 static int __maybe_unused elan_resume(struct device *dev)
1073 {
1074 	struct i2c_client *client = to_i2c_client(dev);
1075 	struct elan_tp_data *data = i2c_get_clientdata(client);
1076 	int error;
1077 
1078 	if (device_may_wakeup(dev) && data->irq_wake) {
1079 		disable_irq_wake(client->irq);
1080 		data->irq_wake = false;
1081 	}
1082 
1083 	error = elan_enable_power(data);
1084 	if (error)
1085 		dev_err(dev, "power up when resuming failed: %d\n", error);
1086 
1087 	error = elan_initialize(data);
1088 	if (error)
1089 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1090 
1091 	enable_irq(data->client->irq);
1092 
1093 	return 0;
1094 }
1095 
1096 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1097 
1098 static const struct i2c_device_id elan_id[] = {
1099 	{ DRIVER_NAME, 0 },
1100 	{ },
1101 };
1102 MODULE_DEVICE_TABLE(i2c, elan_id);
1103 
1104 #ifdef CONFIG_ACPI
1105 static const struct acpi_device_id elan_acpi_id[] = {
1106 	{ "ELAN0000", 0 },
1107 	{ }
1108 };
1109 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1110 #endif
1111 
1112 #ifdef CONFIG_OF
1113 static const struct of_device_id elan_of_match[] = {
1114 	{ .compatible = "elan,ekth3000" },
1115 	{ /* sentinel */ }
1116 };
1117 MODULE_DEVICE_TABLE(of, elan_of_match);
1118 #endif
1119 
1120 static struct i2c_driver elan_driver = {
1121 	.driver = {
1122 		.name	= DRIVER_NAME,
1123 		.owner	= THIS_MODULE,
1124 		.pm	= &elan_pm_ops,
1125 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1126 		.of_match_table = of_match_ptr(elan_of_match),
1127 	},
1128 	.probe		= elan_probe,
1129 	.id_table	= elan_id,
1130 };
1131 
1132 module_i2c_driver(elan_driver);
1133 
1134 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1135 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1136 MODULE_LICENSE("GPL");
1137 MODULE_VERSION(ELAN_DRIVER_VERSION);
1138