xref: /linux/drivers/input/mouse/elan_i2c_core.c (revision 9d796e66230205cd3366f5660387bd9ecca9d336)
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: 1.5.6
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	"1.5.6"
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 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
115 	return error;
116 }
117 
118 static int elan_disable_power(struct elan_tp_data *data)
119 {
120 	int repeat = ETP_RETRY_COUNT;
121 	int error;
122 
123 	do {
124 		error = data->ops->power_control(data->client, false);
125 		if (!error) {
126 			error = regulator_disable(data->vcc);
127 			if (error) {
128 				dev_err(&data->client->dev,
129 					"failed to disable regulator: %d\n",
130 					error);
131 				/* Attempt to power the chip back up */
132 				data->ops->power_control(data->client, true);
133 				break;
134 			}
135 
136 			return 0;
137 		}
138 
139 		msleep(30);
140 	} while (--repeat > 0);
141 
142 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
143 	return error;
144 }
145 
146 static int elan_sleep(struct elan_tp_data *data)
147 {
148 	int repeat = ETP_RETRY_COUNT;
149 	int error;
150 
151 	do {
152 		error = data->ops->sleep_control(data->client, true);
153 		if (!error)
154 			return 0;
155 
156 		msleep(30);
157 	} while (--repeat > 0);
158 
159 	return error;
160 }
161 
162 static int __elan_initialize(struct elan_tp_data *data)
163 {
164 	struct i2c_client *client = data->client;
165 	int error;
166 
167 	error = data->ops->initialize(client);
168 	if (error) {
169 		dev_err(&client->dev, "device initialize failed: %d\n", error);
170 		return error;
171 	}
172 
173 	data->mode |= ETP_ENABLE_ABS;
174 	error = data->ops->set_mode(client, data->mode);
175 	if (error) {
176 		dev_err(&client->dev,
177 			"failed to switch to absolute mode: %d\n", error);
178 		return error;
179 	}
180 
181 	error = data->ops->sleep_control(client, false);
182 	if (error) {
183 		dev_err(&client->dev,
184 			"failed to wake device up: %d\n", error);
185 		return error;
186 	}
187 
188 	return 0;
189 }
190 
191 static int elan_initialize(struct elan_tp_data *data)
192 {
193 	int repeat = ETP_RETRY_COUNT;
194 	int error;
195 
196 	do {
197 		error = __elan_initialize(data);
198 		if (!error)
199 			return 0;
200 
201 		msleep(30);
202 	} while (--repeat > 0);
203 
204 	return error;
205 }
206 
207 static int elan_query_device_info(struct elan_tp_data *data)
208 {
209 	int error;
210 
211 	error = data->ops->get_product_id(data->client, &data->product_id);
212 	if (error)
213 		return error;
214 
215 	error = data->ops->get_version(data->client, false, &data->fw_version);
216 	if (error)
217 		return error;
218 
219 	error = data->ops->get_checksum(data->client, false,
220 					&data->fw_checksum);
221 	if (error)
222 		return error;
223 
224 	error = data->ops->get_sm_version(data->client, &data->sm_version);
225 	if (error)
226 		return error;
227 
228 	error = data->ops->get_version(data->client, true, &data->iap_version);
229 	if (error)
230 		return error;
231 
232 	return 0;
233 }
234 
235 static unsigned int elan_convert_resolution(u8 val)
236 {
237 	/*
238 	 * (value from firmware) * 10 + 790 = dpi
239 	 *
240 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
241 	 * point).
242 	 */
243 
244 	return ((int)(char)val * 10 + 790) * 10 / 254;
245 }
246 
247 static int elan_query_device_parameters(struct elan_tp_data *data)
248 {
249 	unsigned int x_traces, y_traces;
250 	u8 hw_x_res, hw_y_res;
251 	int error;
252 
253 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
254 	if (error)
255 		return error;
256 
257 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
258 	if (error)
259 		return error;
260 
261 	data->width_x = data->max_x / x_traces;
262 	data->width_y = data->max_y / y_traces;
263 
264 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
265 	if (error)
266 		return error;
267 
268 	data->x_res = elan_convert_resolution(hw_x_res);
269 	data->y_res = elan_convert_resolution(hw_y_res);
270 
271 	return 0;
272 }
273 
274 /*
275  **********************************************************
276  * IAP firmware updater related routines
277  **********************************************************
278  */
279 static int elan_write_fw_block(struct elan_tp_data *data,
280 			       const u8 *page, u16 checksum, int idx)
281 {
282 	int retry = ETP_RETRY_COUNT;
283 	int error;
284 
285 	do {
286 		error = data->ops->write_fw_block(data->client,
287 						  page, checksum, idx);
288 		if (!error)
289 			return 0;
290 
291 		dev_dbg(&data->client->dev,
292 			"IAP retrying page %d (error: %d)\n", idx, error);
293 	} while (--retry > 0);
294 
295 	return error;
296 }
297 
298 static int __elan_update_firmware(struct elan_tp_data *data,
299 				  const struct firmware *fw)
300 {
301 	struct i2c_client *client = data->client;
302 	struct device *dev = &client->dev;
303 	int i, j;
304 	int error;
305 	u16 iap_start_addr;
306 	u16 boot_page_count;
307 	u16 sw_checksum = 0, fw_checksum = 0;
308 
309 	error = data->ops->prepare_fw_update(client);
310 	if (error)
311 		return error;
312 
313 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
314 
315 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
316 	for (i = boot_page_count; i < ETP_FW_VAILDPAGE_COUNT; i++) {
317 		u16 checksum = 0;
318 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
319 
320 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
321 			checksum += ((page[j + 1] << 8) | page[j]);
322 
323 		error = elan_write_fw_block(data, page, checksum, i);
324 		if (error) {
325 			dev_err(dev, "write page %d fail: %d\n", i, error);
326 			return error;
327 		}
328 
329 		sw_checksum += checksum;
330 	}
331 
332 	/* Wait WDT reset and power on reset */
333 	msleep(600);
334 
335 	error = data->ops->finish_fw_update(client, &data->fw_completion);
336 	if (error)
337 		return error;
338 
339 	error = data->ops->get_checksum(client, true, &fw_checksum);
340 	if (error)
341 		return error;
342 
343 	if (sw_checksum != fw_checksum) {
344 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
345 			sw_checksum, fw_checksum);
346 		return -EIO;
347 	}
348 
349 	return 0;
350 }
351 
352 static int elan_update_firmware(struct elan_tp_data *data,
353 				const struct firmware *fw)
354 {
355 	struct i2c_client *client = data->client;
356 	int retval;
357 
358 	dev_dbg(&client->dev, "Starting firmware update....\n");
359 
360 	disable_irq(client->irq);
361 	data->in_fw_update = true;
362 
363 	retval = __elan_update_firmware(data, fw);
364 	if (retval) {
365 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
366 		data->ops->iap_reset(client);
367 	} else {
368 		/* Reinitialize TP after fw is updated */
369 		elan_initialize(data);
370 		elan_query_device_info(data);
371 	}
372 
373 	data->in_fw_update = false;
374 	enable_irq(client->irq);
375 
376 	return retval;
377 }
378 
379 /*
380  *******************************************************************
381  * SYSFS attributes
382  *******************************************************************
383  */
384 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
385 					   struct device_attribute *attr,
386 					   char *buf)
387 {
388 	struct i2c_client *client = to_i2c_client(dev);
389 	struct elan_tp_data *data = i2c_get_clientdata(client);
390 
391 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
392 }
393 
394 static ssize_t elan_sysfs_read_product_id(struct device *dev,
395 					 struct device_attribute *attr,
396 					 char *buf)
397 {
398 	struct i2c_client *client = to_i2c_client(dev);
399 	struct elan_tp_data *data = i2c_get_clientdata(client);
400 
401 	return sprintf(buf, "%d.0\n", data->product_id);
402 }
403 
404 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
405 				      struct device_attribute *attr,
406 				      char *buf)
407 {
408 	struct i2c_client *client = to_i2c_client(dev);
409 	struct elan_tp_data *data = i2c_get_clientdata(client);
410 
411 	return sprintf(buf, "%d.0\n", data->fw_version);
412 }
413 
414 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
415 				      struct device_attribute *attr,
416 				      char *buf)
417 {
418 	struct i2c_client *client = to_i2c_client(dev);
419 	struct elan_tp_data *data = i2c_get_clientdata(client);
420 
421 	return sprintf(buf, "%d.0\n", data->sm_version);
422 }
423 
424 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
425 				       struct device_attribute *attr,
426 				       char *buf)
427 {
428 	struct i2c_client *client = to_i2c_client(dev);
429 	struct elan_tp_data *data = i2c_get_clientdata(client);
430 
431 	return sprintf(buf, "%d.0\n", data->iap_version);
432 }
433 
434 static ssize_t elan_sysfs_update_fw(struct device *dev,
435 				    struct device_attribute *attr,
436 				    const char *buf, size_t count)
437 {
438 	struct elan_tp_data *data = dev_get_drvdata(dev);
439 	const struct firmware *fw;
440 	int error;
441 	const u8 *fw_signature;
442 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
443 
444 	error = request_firmware(&fw, ETP_FW_NAME, dev);
445 	if (error) {
446 		dev_err(dev, "cannot load firmware %s: %d\n",
447 			ETP_FW_NAME, error);
448 		return error;
449 	}
450 
451 	/* Firmware file must match signature data */
452 	fw_signature = &fw->data[ETP_FW_SIGNATURE_ADDRESS];
453 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
454 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
455 			(int)sizeof(signature), signature,
456 			(int)sizeof(signature), fw_signature);
457 		error = -EBADF;
458 		goto out_release_fw;
459 	}
460 
461 	error = mutex_lock_interruptible(&data->sysfs_mutex);
462 	if (error)
463 		goto out_release_fw;
464 
465 	error = elan_update_firmware(data, fw);
466 
467 	mutex_unlock(&data->sysfs_mutex);
468 
469 out_release_fw:
470 	release_firmware(fw);
471 	return error ?: count;
472 }
473 
474 static ssize_t calibrate_store(struct device *dev,
475 			       struct device_attribute *attr,
476 			       const char *buf, size_t count)
477 {
478 	struct i2c_client *client = to_i2c_client(dev);
479 	struct elan_tp_data *data = i2c_get_clientdata(client);
480 	int tries = 20;
481 	int retval;
482 	int error;
483 	u8 val[3];
484 
485 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
486 	if (retval)
487 		return retval;
488 
489 	disable_irq(client->irq);
490 
491 	data->mode |= ETP_ENABLE_CALIBRATE;
492 	retval = data->ops->set_mode(client, data->mode);
493 	if (retval) {
494 		dev_err(dev, "failed to enable calibration mode: %d\n",
495 			retval);
496 		goto out;
497 	}
498 
499 	retval = data->ops->calibrate(client);
500 	if (retval) {
501 		dev_err(dev, "failed to start calibration: %d\n",
502 			retval);
503 		goto out_disable_calibrate;
504 	}
505 
506 	val[0] = 0xff;
507 	do {
508 		/* Wait 250ms before checking if calibration has completed. */
509 		msleep(250);
510 
511 		retval = data->ops->calibrate_result(client, val);
512 		if (retval)
513 			dev_err(dev, "failed to check calibration result: %d\n",
514 				retval);
515 		else if (val[0] == 0)
516 			break; /* calibration done */
517 
518 	} while (--tries);
519 
520 	if (tries == 0) {
521 		dev_err(dev, "failed to calibrate. Timeout.\n");
522 		retval = -ETIMEDOUT;
523 	}
524 
525 out_disable_calibrate:
526 	data->mode &= ~ETP_ENABLE_CALIBRATE;
527 	error = data->ops->set_mode(data->client, data->mode);
528 	if (error) {
529 		dev_err(dev, "failed to disable calibration mode: %d\n",
530 			error);
531 		if (!retval)
532 			retval = error;
533 	}
534 out:
535 	enable_irq(client->irq);
536 	mutex_unlock(&data->sysfs_mutex);
537 	return retval ?: count;
538 }
539 
540 static ssize_t elan_sysfs_read_mode(struct device *dev,
541 				    struct device_attribute *attr,
542 				    char *buf)
543 {
544 	struct i2c_client *client = to_i2c_client(dev);
545 	struct elan_tp_data *data = i2c_get_clientdata(client);
546 	int error;
547 	enum tp_mode mode;
548 
549 	error = mutex_lock_interruptible(&data->sysfs_mutex);
550 	if (error)
551 		return error;
552 
553 	error = data->ops->iap_get_mode(data->client, &mode);
554 
555 	mutex_unlock(&data->sysfs_mutex);
556 
557 	if (error)
558 		return error;
559 
560 	return sprintf(buf, "%d\n", (int)mode);
561 }
562 
563 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
564 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
565 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
566 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
567 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
568 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
569 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
570 
571 static DEVICE_ATTR_WO(calibrate);
572 
573 static struct attribute *elan_sysfs_entries[] = {
574 	&dev_attr_product_id.attr,
575 	&dev_attr_firmware_version.attr,
576 	&dev_attr_sample_version.attr,
577 	&dev_attr_iap_version.attr,
578 	&dev_attr_fw_checksum.attr,
579 	&dev_attr_calibrate.attr,
580 	&dev_attr_mode.attr,
581 	&dev_attr_update_fw.attr,
582 	NULL,
583 };
584 
585 static const struct attribute_group elan_sysfs_group = {
586 	.attrs = elan_sysfs_entries,
587 };
588 
589 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
590 			     const char *buf, size_t count)
591 {
592 	struct i2c_client *client = to_i2c_client(dev);
593 	struct elan_tp_data *data = i2c_get_clientdata(client);
594 	int error;
595 	int retval;
596 
597 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
598 	if (retval)
599 		return retval;
600 
601 	disable_irq(client->irq);
602 
603 	data->baseline_ready = false;
604 
605 	data->mode |= ETP_ENABLE_CALIBRATE;
606 	retval = data->ops->set_mode(data->client, data->mode);
607 	if (retval) {
608 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
609 			retval);
610 		goto out;
611 	}
612 
613 	msleep(250);
614 
615 	retval = data->ops->get_baseline_data(data->client, true,
616 					      &data->max_baseline);
617 	if (retval) {
618 		dev_err(dev, "Failed to read max baseline form device: %d\n",
619 			retval);
620 		goto out_disable_calibrate;
621 	}
622 
623 	retval = data->ops->get_baseline_data(data->client, false,
624 					      &data->min_baseline);
625 	if (retval) {
626 		dev_err(dev, "Failed to read min baseline form device: %d\n",
627 			retval);
628 		goto out_disable_calibrate;
629 	}
630 
631 	data->baseline_ready = true;
632 
633 out_disable_calibrate:
634 	data->mode &= ~ETP_ENABLE_CALIBRATE;
635 	error = data->ops->set_mode(data->client, data->mode);
636 	if (error) {
637 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
638 			error);
639 		if (!retval)
640 			retval = error;
641 	}
642 out:
643 	enable_irq(client->irq);
644 	mutex_unlock(&data->sysfs_mutex);
645 	return retval ?: count;
646 }
647 
648 static ssize_t min_show(struct device *dev,
649 			struct device_attribute *attr, char *buf)
650 {
651 	struct i2c_client *client = to_i2c_client(dev);
652 	struct elan_tp_data *data = i2c_get_clientdata(client);
653 	int retval;
654 
655 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
656 	if (retval)
657 		return retval;
658 
659 	if (!data->baseline_ready) {
660 		retval = -ENODATA;
661 		goto out;
662 	}
663 
664 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
665 
666 out:
667 	mutex_unlock(&data->sysfs_mutex);
668 	return retval;
669 }
670 
671 static ssize_t max_show(struct device *dev,
672 			struct device_attribute *attr, char *buf)
673 {
674 	struct i2c_client *client = to_i2c_client(dev);
675 	struct elan_tp_data *data = i2c_get_clientdata(client);
676 	int retval;
677 
678 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
679 	if (retval)
680 		return retval;
681 
682 	if (!data->baseline_ready) {
683 		retval = -ENODATA;
684 		goto out;
685 	}
686 
687 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
688 
689 out:
690 	mutex_unlock(&data->sysfs_mutex);
691 	return retval;
692 }
693 
694 
695 static DEVICE_ATTR_WO(acquire);
696 static DEVICE_ATTR_RO(min);
697 static DEVICE_ATTR_RO(max);
698 
699 static struct attribute *elan_baseline_sysfs_entries[] = {
700 	&dev_attr_acquire.attr,
701 	&dev_attr_min.attr,
702 	&dev_attr_max.attr,
703 	NULL,
704 };
705 
706 static const struct attribute_group elan_baseline_sysfs_group = {
707 	.name = "baseline",
708 	.attrs = elan_baseline_sysfs_entries,
709 };
710 
711 static const struct attribute_group *elan_sysfs_groups[] = {
712 	&elan_sysfs_group,
713 	&elan_baseline_sysfs_group,
714 	NULL
715 };
716 
717 /*
718  ******************************************************************
719  * Elan isr functions
720  ******************************************************************
721  */
722 static void elan_report_contact(struct elan_tp_data *data,
723 				int contact_num, bool contact_valid,
724 				u8 *finger_data)
725 {
726 	struct input_dev *input = data->input;
727 	unsigned int pos_x, pos_y;
728 	unsigned int pressure, mk_x, mk_y;
729 	unsigned int area_x, area_y, major, minor, new_pressure;
730 
731 
732 	if (contact_valid) {
733 		pos_x = ((finger_data[0] & 0xf0) << 4) |
734 						finger_data[1];
735 		pos_y = ((finger_data[0] & 0x0f) << 8) |
736 						finger_data[2];
737 		mk_x = (finger_data[3] & 0x0f);
738 		mk_y = (finger_data[3] >> 4);
739 		pressure = finger_data[4];
740 
741 		if (pos_x > data->max_x || pos_y > data->max_y) {
742 			dev_dbg(input->dev.parent,
743 				"[%d] x=%d y=%d over max (%d, %d)",
744 				contact_num, pos_x, pos_y,
745 				data->max_x, data->max_y);
746 			return;
747 		}
748 
749 		/*
750 		 * To avoid treating large finger as palm, let's reduce the
751 		 * width x and y per trace.
752 		 */
753 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
754 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
755 
756 		major = max(area_x, area_y);
757 		minor = min(area_x, area_y);
758 
759 		new_pressure = pressure + ETP_PRESSURE_OFFSET;
760 		if (new_pressure > ETP_MAX_PRESSURE)
761 			new_pressure = ETP_MAX_PRESSURE;
762 
763 		input_mt_slot(input, contact_num);
764 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
765 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
766 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
767 		input_report_abs(input, ABS_MT_PRESSURE, new_pressure);
768 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
769 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
770 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
771 	} else {
772 		input_mt_slot(input, contact_num);
773 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
774 	}
775 }
776 
777 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
778 {
779 	struct input_dev *input = data->input;
780 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
781 	int i;
782 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
783 	bool contact_valid;
784 
785 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
786 		contact_valid = tp_info & (1U << (3 + i));
787 		elan_report_contact(data, i, contact_valid, finger_data);
788 
789 		if (contact_valid)
790 			finger_data += ETP_FINGER_DATA_LEN;
791 	}
792 
793 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
794 	input_mt_report_pointer_emulation(input, true);
795 	input_sync(input);
796 }
797 
798 static irqreturn_t elan_isr(int irq, void *dev_id)
799 {
800 	struct elan_tp_data *data = dev_id;
801 	struct device *dev = &data->client->dev;
802 	int error;
803 	u8 report[ETP_MAX_REPORT_LEN];
804 
805 	/*
806 	 * When device is connected to i2c bus, when all IAP page writes
807 	 * complete, the driver will receive interrupt and must read
808 	 * 0000 to confirm that IAP is finished.
809 	*/
810 	if (data->in_fw_update) {
811 		complete(&data->fw_completion);
812 		goto out;
813 	}
814 
815 	error = data->ops->get_report(data->client, report);
816 	if (error)
817 		goto out;
818 
819 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
820 		dev_err(dev, "invalid report id data (%x)\n",
821 			report[ETP_REPORT_ID_OFFSET]);
822 	else
823 		elan_report_absolute(data, report);
824 
825 out:
826 	return IRQ_HANDLED;
827 }
828 
829 /*
830  ******************************************************************
831  * Elan initialization functions
832  ******************************************************************
833  */
834 static int elan_setup_input_device(struct elan_tp_data *data)
835 {
836 	struct device *dev = &data->client->dev;
837 	struct input_dev *input;
838 	unsigned int max_width = max(data->width_x, data->width_y);
839 	unsigned int min_width = min(data->width_x, data->width_y);
840 	int error;
841 
842 	input = devm_input_allocate_device(dev);
843 	if (!input)
844 		return -ENOMEM;
845 
846 	input->name = "Elan Touchpad";
847 	input->id.bustype = BUS_I2C;
848 	input_set_drvdata(input, data);
849 
850 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
851 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
852 	if (error) {
853 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
854 		return error;
855 	}
856 
857 	__set_bit(EV_ABS, input->evbit);
858 	__set_bit(INPUT_PROP_POINTER, input->propbit);
859 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
860 	__set_bit(BTN_LEFT, input->keybit);
861 
862 	/* Set up ST parameters */
863 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
864 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
865 	input_abs_set_res(input, ABS_X, data->x_res);
866 	input_abs_set_res(input, ABS_Y, data->y_res);
867 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
868 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
869 
870 	/* And MT parameters */
871 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
872 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
873 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
874 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
875 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
876 			     ETP_MAX_PRESSURE, 0, 0);
877 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
878 			     ETP_FINGER_WIDTH * max_width, 0, 0);
879 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
880 			     ETP_FINGER_WIDTH * min_width, 0, 0);
881 
882 	data->input = input;
883 
884 	return 0;
885 }
886 
887 static void elan_disable_regulator(void *_data)
888 {
889 	struct elan_tp_data *data = _data;
890 
891 	regulator_disable(data->vcc);
892 }
893 
894 static void elan_remove_sysfs_groups(void *_data)
895 {
896 	struct elan_tp_data *data = _data;
897 
898 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
899 }
900 
901 static int elan_probe(struct i2c_client *client,
902 		      const struct i2c_device_id *dev_id)
903 {
904 	const struct elan_transport_ops *transport_ops;
905 	struct device *dev = &client->dev;
906 	struct elan_tp_data *data;
907 	unsigned long irqflags;
908 	int error;
909 
910 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
911 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
912 		transport_ops = &elan_i2c_ops;
913 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
914 		   i2c_check_functionality(client->adapter,
915 					   I2C_FUNC_SMBUS_BYTE_DATA |
916 						I2C_FUNC_SMBUS_BLOCK_DATA |
917 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
918 		transport_ops = &elan_smbus_ops;
919 	} else {
920 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
921 		return -EIO;
922 	}
923 
924 	data = devm_kzalloc(&client->dev, sizeof(struct elan_tp_data),
925 			    GFP_KERNEL);
926 	if (!data)
927 		return -ENOMEM;
928 
929 	i2c_set_clientdata(client, data);
930 
931 	data->ops = transport_ops;
932 	data->client = client;
933 	init_completion(&data->fw_completion);
934 	mutex_init(&data->sysfs_mutex);
935 
936 	data->vcc = devm_regulator_get(&client->dev, "vcc");
937 	if (IS_ERR(data->vcc)) {
938 		error = PTR_ERR(data->vcc);
939 		if (error != -EPROBE_DEFER)
940 			dev_err(&client->dev,
941 				"Failed to get 'vcc' regulator: %d\n",
942 				error);
943 		return error;
944 	}
945 
946 	error = regulator_enable(data->vcc);
947 	if (error) {
948 		dev_err(&client->dev,
949 			"Failed to enable regulator: %d\n", error);
950 		return error;
951 	}
952 
953 	error = devm_add_action(&client->dev,
954 				elan_disable_regulator, data);
955 	if (error) {
956 		regulator_disable(data->vcc);
957 		dev_err(&client->dev,
958 			"Failed to add disable regulator action: %d\n",
959 			error);
960 		return error;
961 	}
962 
963 	/* Initialize the touchpad. */
964 	error = elan_initialize(data);
965 	if (error)
966 		return error;
967 
968 	error = elan_query_device_info(data);
969 	if (error)
970 		return error;
971 
972 	error = elan_query_device_parameters(data);
973 	if (error)
974 		return error;
975 
976 	dev_dbg(&client->dev,
977 		"Elan Touchpad Information:\n"
978 		"    Module product ID:  0x%04x\n"
979 		"    Firmware Version:  0x%04x\n"
980 		"    Sample Version:  0x%04x\n"
981 		"    IAP Version:  0x%04x\n"
982 		"    Max ABS X,Y:   %d,%d\n"
983 		"    Width X,Y:   %d,%d\n"
984 		"    Resolution X,Y:   %d,%d (dots/mm)\n",
985 		data->product_id,
986 		data->fw_version,
987 		data->sm_version,
988 		data->iap_version,
989 		data->max_x, data->max_y,
990 		data->width_x, data->width_y,
991 		data->x_res, data->y_res);
992 
993 	/* Set up input device properties based on queried parameters. */
994 	error = elan_setup_input_device(data);
995 	if (error)
996 		return error;
997 
998 	/*
999 	 * Systems using device tree should set up interrupt via DTS,
1000 	 * the rest will use the default falling edge interrupts.
1001 	 */
1002 	irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
1003 
1004 	error = devm_request_threaded_irq(&client->dev, client->irq,
1005 					  NULL, elan_isr,
1006 					  irqflags | IRQF_ONESHOT,
1007 					  client->name, data);
1008 	if (error) {
1009 		dev_err(&client->dev, "cannot register irq=%d\n", client->irq);
1010 		return error;
1011 	}
1012 
1013 	error = sysfs_create_groups(&client->dev.kobj, elan_sysfs_groups);
1014 	if (error) {
1015 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1016 			error);
1017 		return error;
1018 	}
1019 
1020 	error = devm_add_action(&client->dev,
1021 				elan_remove_sysfs_groups, data);
1022 	if (error) {
1023 		elan_remove_sysfs_groups(data);
1024 		dev_err(&client->dev,
1025 			"Failed to add sysfs cleanup action: %d\n",
1026 			error);
1027 		return error;
1028 	}
1029 
1030 	error = input_register_device(data->input);
1031 	if (error) {
1032 		dev_err(&client->dev, "failed to register input device: %d\n",
1033 			error);
1034 		return error;
1035 	}
1036 
1037 	/*
1038 	 * Systems using device tree should set up wakeup via DTS,
1039 	 * the rest will configure device as wakeup source by default.
1040 	 */
1041 	if (!client->dev.of_node)
1042 		device_init_wakeup(&client->dev, true);
1043 
1044 	return 0;
1045 }
1046 
1047 static int __maybe_unused elan_suspend(struct device *dev)
1048 {
1049 	struct i2c_client *client = to_i2c_client(dev);
1050 	struct elan_tp_data *data = i2c_get_clientdata(client);
1051 	int ret;
1052 
1053 	/*
1054 	 * We are taking the mutex to make sure sysfs operations are
1055 	 * complete before we attempt to bring the device into low[er]
1056 	 * power mode.
1057 	 */
1058 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1059 	if (ret)
1060 		return ret;
1061 
1062 	disable_irq(client->irq);
1063 
1064 	if (device_may_wakeup(dev)) {
1065 		ret = elan_sleep(data);
1066 		/* Enable wake from IRQ */
1067 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1068 	} else {
1069 		ret = elan_disable_power(data);
1070 	}
1071 
1072 	mutex_unlock(&data->sysfs_mutex);
1073 	return ret;
1074 }
1075 
1076 static int __maybe_unused elan_resume(struct device *dev)
1077 {
1078 	struct i2c_client *client = to_i2c_client(dev);
1079 	struct elan_tp_data *data = i2c_get_clientdata(client);
1080 	int error;
1081 
1082 	if (device_may_wakeup(dev) && data->irq_wake) {
1083 		disable_irq_wake(client->irq);
1084 		data->irq_wake = false;
1085 	}
1086 
1087 	error = elan_enable_power(data);
1088 	if (error) {
1089 		dev_err(dev, "power up when resuming failed: %d\n", error);
1090 		goto err;
1091 	}
1092 
1093 	error = elan_initialize(data);
1094 	if (error)
1095 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1096 
1097 err:
1098 	enable_irq(data->client->irq);
1099 	return error;
1100 }
1101 
1102 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1103 
1104 static const struct i2c_device_id elan_id[] = {
1105 	{ DRIVER_NAME, 0 },
1106 	{ },
1107 };
1108 MODULE_DEVICE_TABLE(i2c, elan_id);
1109 
1110 #ifdef CONFIG_ACPI
1111 static const struct acpi_device_id elan_acpi_id[] = {
1112 	{ "ELAN0000", 0 },
1113 	{ }
1114 };
1115 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1116 #endif
1117 
1118 #ifdef CONFIG_OF
1119 static const struct of_device_id elan_of_match[] = {
1120 	{ .compatible = "elan,ekth3000" },
1121 	{ /* sentinel */ }
1122 };
1123 MODULE_DEVICE_TABLE(of, elan_of_match);
1124 #endif
1125 
1126 static struct i2c_driver elan_driver = {
1127 	.driver = {
1128 		.name	= DRIVER_NAME,
1129 		.owner	= THIS_MODULE,
1130 		.pm	= &elan_pm_ops,
1131 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1132 		.of_match_table = of_match_ptr(elan_of_match),
1133 	},
1134 	.probe		= elan_probe,
1135 	.id_table	= elan_id,
1136 };
1137 
1138 module_i2c_driver(elan_driver);
1139 
1140 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1141 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1142 MODULE_LICENSE("GPL");
1143 MODULE_VERSION(ELAN_DRIVER_VERSION);
1144