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  * Author: KT Liao <kt.liao@emc.com.tw>
8  * Version: 1.6.3
9  *
10  * Based on cyapa driver:
11  * copyright (c) 2011-2012 Cypress Semiconductor, Inc.
12  * copyright (c) 2011-2012 Google, Inc.
13  *
14  * This program is free software; you can redistribute it and/or modify it
15  * under the terms of the GNU General Public License version 2 as published
16  * by the Free Software Foundation.
17  *
18  * Trademarks are the property of their respective owners.
19  */
20 
21 #include <linux/acpi.h>
22 #include <linux/delay.h>
23 #include <linux/device.h>
24 #include <linux/firmware.h>
25 #include <linux/i2c.h>
26 #include <linux/init.h>
27 #include <linux/input/mt.h>
28 #include <linux/interrupt.h>
29 #include <linux/irq.h>
30 #include <linux/module.h>
31 #include <linux/slab.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/input.h>
35 #include <linux/uaccess.h>
36 #include <linux/jiffies.h>
37 #include <linux/completion.h>
38 #include <linux/of.h>
39 #include <linux/regulator/consumer.h>
40 #include <asm/unaligned.h>
41 
42 #include "elan_i2c.h"
43 
44 #define DRIVER_NAME		"elan_i2c"
45 #define ELAN_DRIVER_VERSION	"1.6.3"
46 #define ELAN_VENDOR_ID		0x04f3
47 #define ETP_MAX_PRESSURE	255
48 #define ETP_FWIDTH_REDUCE	90
49 #define ETP_FINGER_WIDTH	15
50 #define ETP_RETRY_COUNT		3
51 
52 #define ETP_MAX_FINGERS		5
53 #define ETP_FINGER_DATA_LEN	5
54 #define ETP_REPORT_ID		0x5D
55 #define ETP_REPORT_ID_OFFSET	2
56 #define ETP_TOUCH_INFO_OFFSET	3
57 #define ETP_FINGER_DATA_OFFSET	4
58 #define ETP_HOVER_INFO_OFFSET	30
59 #define ETP_MAX_REPORT_LEN	34
60 
61 /* The main device structure */
62 struct elan_tp_data {
63 	struct i2c_client	*client;
64 	struct input_dev	*input;
65 	struct regulator	*vcc;
66 
67 	const struct elan_transport_ops *ops;
68 
69 	/* for fw update */
70 	struct completion	fw_completion;
71 	bool			in_fw_update;
72 
73 	struct mutex		sysfs_mutex;
74 
75 	unsigned int		max_x;
76 	unsigned int		max_y;
77 	unsigned int		width_x;
78 	unsigned int		width_y;
79 	unsigned int		x_res;
80 	unsigned int		y_res;
81 
82 	u8			pattern;
83 	u16			product_id;
84 	u8			fw_version;
85 	u8			sm_version;
86 	u8			iap_version;
87 	u16			fw_checksum;
88 	int			pressure_adjustment;
89 	u8			mode;
90 	u16			ic_type;
91 	u16			fw_validpage_count;
92 	u16			fw_signature_address;
93 
94 	bool			irq_wake;
95 
96 	u8			min_baseline;
97 	u8			max_baseline;
98 	bool			baseline_ready;
99 	u8			clickpad;
100 };
101 
102 static int elan_get_fwinfo(u16 ic_type, u16 *validpage_count,
103 			   u16 *signature_address)
104 {
105 	switch (ic_type) {
106 	case 0x00:
107 	case 0x06:
108 	case 0x08:
109 		*validpage_count = 512;
110 		break;
111 	case 0x03:
112 	case 0x07:
113 	case 0x09:
114 	case 0x0A:
115 	case 0x0B:
116 	case 0x0C:
117 		*validpage_count = 768;
118 		break;
119 	case 0x0D:
120 		*validpage_count = 896;
121 		break;
122 	case 0x0E:
123 		*validpage_count = 640;
124 		break;
125 	case 0x10:
126 		*validpage_count = 1024;
127 		break;
128 	default:
129 		/* unknown ic type clear value */
130 		*validpage_count = 0;
131 		*signature_address = 0;
132 		return -ENXIO;
133 	}
134 
135 	*signature_address =
136 		(*validpage_count * ETP_FW_PAGE_SIZE) - ETP_FW_SIGNATURE_SIZE;
137 
138 	return 0;
139 }
140 
141 static int elan_enable_power(struct elan_tp_data *data)
142 {
143 	int repeat = ETP_RETRY_COUNT;
144 	int error;
145 
146 	error = regulator_enable(data->vcc);
147 	if (error) {
148 		dev_err(&data->client->dev,
149 			"failed to enable regulator: %d\n", error);
150 		return error;
151 	}
152 
153 	do {
154 		error = data->ops->power_control(data->client, true);
155 		if (error >= 0)
156 			return 0;
157 
158 		msleep(30);
159 	} while (--repeat > 0);
160 
161 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
162 	return error;
163 }
164 
165 static int elan_disable_power(struct elan_tp_data *data)
166 {
167 	int repeat = ETP_RETRY_COUNT;
168 	int error;
169 
170 	do {
171 		error = data->ops->power_control(data->client, false);
172 		if (!error) {
173 			error = regulator_disable(data->vcc);
174 			if (error) {
175 				dev_err(&data->client->dev,
176 					"failed to disable regulator: %d\n",
177 					error);
178 				/* Attempt to power the chip back up */
179 				data->ops->power_control(data->client, true);
180 				break;
181 			}
182 
183 			return 0;
184 		}
185 
186 		msleep(30);
187 	} while (--repeat > 0);
188 
189 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
190 	return error;
191 }
192 
193 static int elan_sleep(struct elan_tp_data *data)
194 {
195 	int repeat = ETP_RETRY_COUNT;
196 	int error;
197 
198 	do {
199 		error = data->ops->sleep_control(data->client, true);
200 		if (!error)
201 			return 0;
202 
203 		msleep(30);
204 	} while (--repeat > 0);
205 
206 	return error;
207 }
208 
209 static int elan_query_product(struct elan_tp_data *data)
210 {
211 	int error;
212 
213 	error = data->ops->get_product_id(data->client, &data->product_id);
214 	if (error)
215 		return error;
216 
217 	error = data->ops->get_sm_version(data->client, &data->ic_type,
218 					  &data->sm_version, &data->clickpad);
219 	if (error)
220 		return error;
221 
222 	return 0;
223 }
224 
225 static int elan_check_ASUS_special_fw(struct elan_tp_data *data)
226 {
227 	if (data->ic_type == 0x0E) {
228 		switch (data->product_id) {
229 		case 0x05 ... 0x07:
230 		case 0x09:
231 		case 0x13:
232 			return true;
233 		}
234 	} else if (data->ic_type == 0x08 && data->product_id == 0x26) {
235 		/* ASUS EeeBook X205TA */
236 		return true;
237 	}
238 
239 	return false;
240 }
241 
242 static int __elan_initialize(struct elan_tp_data *data)
243 {
244 	struct i2c_client *client = data->client;
245 	bool woken_up = false;
246 	int error;
247 
248 	error = data->ops->initialize(client);
249 	if (error) {
250 		dev_err(&client->dev, "device initialize failed: %d\n", error);
251 		return error;
252 	}
253 
254 	error = elan_query_product(data);
255 	if (error)
256 		return error;
257 
258 	/*
259 	 * Some ASUS devices were shipped with firmware that requires
260 	 * touchpads to be woken up first, before attempting to switch
261 	 * them into absolute reporting mode.
262 	 */
263 	if (elan_check_ASUS_special_fw(data)) {
264 		error = data->ops->sleep_control(client, false);
265 		if (error) {
266 			dev_err(&client->dev,
267 				"failed to wake device up: %d\n", error);
268 			return error;
269 		}
270 
271 		msleep(200);
272 		woken_up = true;
273 	}
274 
275 	data->mode |= ETP_ENABLE_ABS;
276 	error = data->ops->set_mode(client, data->mode);
277 	if (error) {
278 		dev_err(&client->dev,
279 			"failed to switch to absolute mode: %d\n", error);
280 		return error;
281 	}
282 
283 	if (!woken_up) {
284 		error = data->ops->sleep_control(client, false);
285 		if (error) {
286 			dev_err(&client->dev,
287 				"failed to wake device up: %d\n", error);
288 			return error;
289 		}
290 	}
291 
292 	return 0;
293 }
294 
295 static int elan_initialize(struct elan_tp_data *data)
296 {
297 	int repeat = ETP_RETRY_COUNT;
298 	int error;
299 
300 	do {
301 		error = __elan_initialize(data);
302 		if (!error)
303 			return 0;
304 
305 		msleep(30);
306 	} while (--repeat > 0);
307 
308 	return error;
309 }
310 
311 static int elan_query_device_info(struct elan_tp_data *data)
312 {
313 	int error;
314 	u16 ic_type;
315 
316 	error = data->ops->get_version(data->client, false, &data->fw_version);
317 	if (error)
318 		return error;
319 
320 	error = data->ops->get_checksum(data->client, false,
321 					&data->fw_checksum);
322 	if (error)
323 		return error;
324 
325 	error = data->ops->get_version(data->client, true, &data->iap_version);
326 	if (error)
327 		return error;
328 
329 	error = data->ops->get_pressure_adjustment(data->client,
330 						   &data->pressure_adjustment);
331 	if (error)
332 		return error;
333 
334 	error = data->ops->get_pattern(data->client, &data->pattern);
335 	if (error)
336 		return error;
337 
338 	if (data->pattern == 0x01)
339 		ic_type = data->ic_type;
340 	else
341 		ic_type = data->iap_version;
342 
343 	error = elan_get_fwinfo(ic_type, &data->fw_validpage_count,
344 				&data->fw_signature_address);
345 	if (error)
346 		dev_warn(&data->client->dev,
347 			 "unexpected iap version %#04x (ic type: %#04x), firmware update will not work\n",
348 			 data->iap_version, data->ic_type);
349 
350 	return 0;
351 }
352 
353 static unsigned int elan_convert_resolution(u8 val)
354 {
355 	/*
356 	 * (value from firmware) * 10 + 790 = dpi
357 	 *
358 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
359 	 * point).
360 	 */
361 
362 	return ((int)(char)val * 10 + 790) * 10 / 254;
363 }
364 
365 static int elan_query_device_parameters(struct elan_tp_data *data)
366 {
367 	unsigned int x_traces, y_traces;
368 	u8 hw_x_res, hw_y_res;
369 	int error;
370 
371 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
372 	if (error)
373 		return error;
374 
375 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
376 	if (error)
377 		return error;
378 
379 	data->width_x = data->max_x / x_traces;
380 	data->width_y = data->max_y / y_traces;
381 
382 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
383 	if (error)
384 		return error;
385 
386 	data->x_res = elan_convert_resolution(hw_x_res);
387 	data->y_res = elan_convert_resolution(hw_y_res);
388 
389 	return 0;
390 }
391 
392 /*
393  **********************************************************
394  * IAP firmware updater related routines
395  **********************************************************
396  */
397 static int elan_write_fw_block(struct elan_tp_data *data,
398 			       const u8 *page, u16 checksum, int idx)
399 {
400 	int retry = ETP_RETRY_COUNT;
401 	int error;
402 
403 	do {
404 		error = data->ops->write_fw_block(data->client,
405 						  page, checksum, idx);
406 		if (!error)
407 			return 0;
408 
409 		dev_dbg(&data->client->dev,
410 			"IAP retrying page %d (error: %d)\n", idx, error);
411 	} while (--retry > 0);
412 
413 	return error;
414 }
415 
416 static int __elan_update_firmware(struct elan_tp_data *data,
417 				  const struct firmware *fw)
418 {
419 	struct i2c_client *client = data->client;
420 	struct device *dev = &client->dev;
421 	int i, j;
422 	int error;
423 	u16 iap_start_addr;
424 	u16 boot_page_count;
425 	u16 sw_checksum = 0, fw_checksum = 0;
426 
427 	error = data->ops->prepare_fw_update(client);
428 	if (error)
429 		return error;
430 
431 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
432 
433 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
434 	for (i = boot_page_count; i < data->fw_validpage_count; i++) {
435 		u16 checksum = 0;
436 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
437 
438 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
439 			checksum += ((page[j + 1] << 8) | page[j]);
440 
441 		error = elan_write_fw_block(data, page, checksum, i);
442 		if (error) {
443 			dev_err(dev, "write page %d fail: %d\n", i, error);
444 			return error;
445 		}
446 
447 		sw_checksum += checksum;
448 	}
449 
450 	/* Wait WDT reset and power on reset */
451 	msleep(600);
452 
453 	error = data->ops->finish_fw_update(client, &data->fw_completion);
454 	if (error)
455 		return error;
456 
457 	error = data->ops->get_checksum(client, true, &fw_checksum);
458 	if (error)
459 		return error;
460 
461 	if (sw_checksum != fw_checksum) {
462 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
463 			sw_checksum, fw_checksum);
464 		return -EIO;
465 	}
466 
467 	return 0;
468 }
469 
470 static int elan_update_firmware(struct elan_tp_data *data,
471 				const struct firmware *fw)
472 {
473 	struct i2c_client *client = data->client;
474 	int retval;
475 
476 	dev_dbg(&client->dev, "Starting firmware update....\n");
477 
478 	disable_irq(client->irq);
479 	data->in_fw_update = true;
480 
481 	retval = __elan_update_firmware(data, fw);
482 	if (retval) {
483 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
484 		data->ops->iap_reset(client);
485 	} else {
486 		/* Reinitialize TP after fw is updated */
487 		elan_initialize(data);
488 		elan_query_device_info(data);
489 	}
490 
491 	data->in_fw_update = false;
492 	enable_irq(client->irq);
493 
494 	return retval;
495 }
496 
497 /*
498  *******************************************************************
499  * SYSFS attributes
500  *******************************************************************
501  */
502 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
503 					   struct device_attribute *attr,
504 					   char *buf)
505 {
506 	struct i2c_client *client = to_i2c_client(dev);
507 	struct elan_tp_data *data = i2c_get_clientdata(client);
508 
509 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
510 }
511 
512 static ssize_t elan_sysfs_read_product_id(struct device *dev,
513 					 struct device_attribute *attr,
514 					 char *buf)
515 {
516 	struct i2c_client *client = to_i2c_client(dev);
517 	struct elan_tp_data *data = i2c_get_clientdata(client);
518 
519 	return sprintf(buf, ETP_PRODUCT_ID_FORMAT_STRING "\n",
520 		       data->product_id);
521 }
522 
523 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
524 				      struct device_attribute *attr,
525 				      char *buf)
526 {
527 	struct i2c_client *client = to_i2c_client(dev);
528 	struct elan_tp_data *data = i2c_get_clientdata(client);
529 
530 	return sprintf(buf, "%d.0\n", data->fw_version);
531 }
532 
533 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
534 				      struct device_attribute *attr,
535 				      char *buf)
536 {
537 	struct i2c_client *client = to_i2c_client(dev);
538 	struct elan_tp_data *data = i2c_get_clientdata(client);
539 
540 	return sprintf(buf, "%d.0\n", data->sm_version);
541 }
542 
543 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
544 				       struct device_attribute *attr,
545 				       char *buf)
546 {
547 	struct i2c_client *client = to_i2c_client(dev);
548 	struct elan_tp_data *data = i2c_get_clientdata(client);
549 
550 	return sprintf(buf, "%d.0\n", data->iap_version);
551 }
552 
553 static ssize_t elan_sysfs_update_fw(struct device *dev,
554 				    struct device_attribute *attr,
555 				    const char *buf, size_t count)
556 {
557 	struct elan_tp_data *data = dev_get_drvdata(dev);
558 	const struct firmware *fw;
559 	char *fw_name;
560 	int error;
561 	const u8 *fw_signature;
562 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
563 
564 	if (data->fw_validpage_count == 0)
565 		return -EINVAL;
566 
567 	/* Look for a firmware with the product id appended. */
568 	fw_name = kasprintf(GFP_KERNEL, ETP_FW_NAME, data->product_id);
569 	if (!fw_name) {
570 		dev_err(dev, "failed to allocate memory for firmware name\n");
571 		return -ENOMEM;
572 	}
573 
574 	dev_info(dev, "requesting fw '%s'\n", fw_name);
575 	error = request_firmware(&fw, fw_name, dev);
576 	kfree(fw_name);
577 	if (error) {
578 		dev_err(dev, "failed to request firmware: %d\n", error);
579 		return error;
580 	}
581 
582 	/* Firmware file must match signature data */
583 	fw_signature = &fw->data[data->fw_signature_address];
584 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
585 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
586 			(int)sizeof(signature), signature,
587 			(int)sizeof(signature), fw_signature);
588 		error = -EBADF;
589 		goto out_release_fw;
590 	}
591 
592 	error = mutex_lock_interruptible(&data->sysfs_mutex);
593 	if (error)
594 		goto out_release_fw;
595 
596 	error = elan_update_firmware(data, fw);
597 
598 	mutex_unlock(&data->sysfs_mutex);
599 
600 out_release_fw:
601 	release_firmware(fw);
602 	return error ?: count;
603 }
604 
605 static ssize_t calibrate_store(struct device *dev,
606 			       struct device_attribute *attr,
607 			       const char *buf, size_t count)
608 {
609 	struct i2c_client *client = to_i2c_client(dev);
610 	struct elan_tp_data *data = i2c_get_clientdata(client);
611 	int tries = 20;
612 	int retval;
613 	int error;
614 	u8 val[3];
615 
616 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
617 	if (retval)
618 		return retval;
619 
620 	disable_irq(client->irq);
621 
622 	data->mode |= ETP_ENABLE_CALIBRATE;
623 	retval = data->ops->set_mode(client, data->mode);
624 	if (retval) {
625 		dev_err(dev, "failed to enable calibration mode: %d\n",
626 			retval);
627 		goto out;
628 	}
629 
630 	retval = data->ops->calibrate(client);
631 	if (retval) {
632 		dev_err(dev, "failed to start calibration: %d\n",
633 			retval);
634 		goto out_disable_calibrate;
635 	}
636 
637 	val[0] = 0xff;
638 	do {
639 		/* Wait 250ms before checking if calibration has completed. */
640 		msleep(250);
641 
642 		retval = data->ops->calibrate_result(client, val);
643 		if (retval)
644 			dev_err(dev, "failed to check calibration result: %d\n",
645 				retval);
646 		else if (val[0] == 0)
647 			break; /* calibration done */
648 
649 	} while (--tries);
650 
651 	if (tries == 0) {
652 		dev_err(dev, "failed to calibrate. Timeout.\n");
653 		retval = -ETIMEDOUT;
654 	}
655 
656 out_disable_calibrate:
657 	data->mode &= ~ETP_ENABLE_CALIBRATE;
658 	error = data->ops->set_mode(data->client, data->mode);
659 	if (error) {
660 		dev_err(dev, "failed to disable calibration mode: %d\n",
661 			error);
662 		if (!retval)
663 			retval = error;
664 	}
665 out:
666 	enable_irq(client->irq);
667 	mutex_unlock(&data->sysfs_mutex);
668 	return retval ?: count;
669 }
670 
671 static ssize_t elan_sysfs_read_mode(struct device *dev,
672 				    struct device_attribute *attr,
673 				    char *buf)
674 {
675 	struct i2c_client *client = to_i2c_client(dev);
676 	struct elan_tp_data *data = i2c_get_clientdata(client);
677 	int error;
678 	enum tp_mode mode;
679 
680 	error = mutex_lock_interruptible(&data->sysfs_mutex);
681 	if (error)
682 		return error;
683 
684 	error = data->ops->iap_get_mode(data->client, &mode);
685 
686 	mutex_unlock(&data->sysfs_mutex);
687 
688 	if (error)
689 		return error;
690 
691 	return sprintf(buf, "%d\n", (int)mode);
692 }
693 
694 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
695 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
696 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
697 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
698 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
699 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
700 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
701 
702 static DEVICE_ATTR_WO(calibrate);
703 
704 static struct attribute *elan_sysfs_entries[] = {
705 	&dev_attr_product_id.attr,
706 	&dev_attr_firmware_version.attr,
707 	&dev_attr_sample_version.attr,
708 	&dev_attr_iap_version.attr,
709 	&dev_attr_fw_checksum.attr,
710 	&dev_attr_calibrate.attr,
711 	&dev_attr_mode.attr,
712 	&dev_attr_update_fw.attr,
713 	NULL,
714 };
715 
716 static const struct attribute_group elan_sysfs_group = {
717 	.attrs = elan_sysfs_entries,
718 };
719 
720 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
721 			     const char *buf, size_t count)
722 {
723 	struct i2c_client *client = to_i2c_client(dev);
724 	struct elan_tp_data *data = i2c_get_clientdata(client);
725 	int error;
726 	int retval;
727 
728 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
729 	if (retval)
730 		return retval;
731 
732 	disable_irq(client->irq);
733 
734 	data->baseline_ready = false;
735 
736 	data->mode |= ETP_ENABLE_CALIBRATE;
737 	retval = data->ops->set_mode(data->client, data->mode);
738 	if (retval) {
739 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
740 			retval);
741 		goto out;
742 	}
743 
744 	msleep(250);
745 
746 	retval = data->ops->get_baseline_data(data->client, true,
747 					      &data->max_baseline);
748 	if (retval) {
749 		dev_err(dev, "Failed to read max baseline form device: %d\n",
750 			retval);
751 		goto out_disable_calibrate;
752 	}
753 
754 	retval = data->ops->get_baseline_data(data->client, false,
755 					      &data->min_baseline);
756 	if (retval) {
757 		dev_err(dev, "Failed to read min baseline form device: %d\n",
758 			retval);
759 		goto out_disable_calibrate;
760 	}
761 
762 	data->baseline_ready = true;
763 
764 out_disable_calibrate:
765 	data->mode &= ~ETP_ENABLE_CALIBRATE;
766 	error = data->ops->set_mode(data->client, data->mode);
767 	if (error) {
768 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
769 			error);
770 		if (!retval)
771 			retval = error;
772 	}
773 out:
774 	enable_irq(client->irq);
775 	mutex_unlock(&data->sysfs_mutex);
776 	return retval ?: count;
777 }
778 
779 static ssize_t min_show(struct device *dev,
780 			struct device_attribute *attr, char *buf)
781 {
782 	struct i2c_client *client = to_i2c_client(dev);
783 	struct elan_tp_data *data = i2c_get_clientdata(client);
784 	int retval;
785 
786 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
787 	if (retval)
788 		return retval;
789 
790 	if (!data->baseline_ready) {
791 		retval = -ENODATA;
792 		goto out;
793 	}
794 
795 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
796 
797 out:
798 	mutex_unlock(&data->sysfs_mutex);
799 	return retval;
800 }
801 
802 static ssize_t max_show(struct device *dev,
803 			struct device_attribute *attr, char *buf)
804 {
805 	struct i2c_client *client = to_i2c_client(dev);
806 	struct elan_tp_data *data = i2c_get_clientdata(client);
807 	int retval;
808 
809 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
810 	if (retval)
811 		return retval;
812 
813 	if (!data->baseline_ready) {
814 		retval = -ENODATA;
815 		goto out;
816 	}
817 
818 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
819 
820 out:
821 	mutex_unlock(&data->sysfs_mutex);
822 	return retval;
823 }
824 
825 
826 static DEVICE_ATTR_WO(acquire);
827 static DEVICE_ATTR_RO(min);
828 static DEVICE_ATTR_RO(max);
829 
830 static struct attribute *elan_baseline_sysfs_entries[] = {
831 	&dev_attr_acquire.attr,
832 	&dev_attr_min.attr,
833 	&dev_attr_max.attr,
834 	NULL,
835 };
836 
837 static const struct attribute_group elan_baseline_sysfs_group = {
838 	.name = "baseline",
839 	.attrs = elan_baseline_sysfs_entries,
840 };
841 
842 static const struct attribute_group *elan_sysfs_groups[] = {
843 	&elan_sysfs_group,
844 	&elan_baseline_sysfs_group,
845 	NULL
846 };
847 
848 /*
849  ******************************************************************
850  * Elan isr functions
851  ******************************************************************
852  */
853 static void elan_report_contact(struct elan_tp_data *data,
854 				int contact_num, bool contact_valid,
855 				u8 *finger_data)
856 {
857 	struct input_dev *input = data->input;
858 	unsigned int pos_x, pos_y;
859 	unsigned int pressure, mk_x, mk_y;
860 	unsigned int area_x, area_y, major, minor;
861 	unsigned int scaled_pressure;
862 
863 	if (contact_valid) {
864 		pos_x = ((finger_data[0] & 0xf0) << 4) |
865 						finger_data[1];
866 		pos_y = ((finger_data[0] & 0x0f) << 8) |
867 						finger_data[2];
868 		mk_x = (finger_data[3] & 0x0f);
869 		mk_y = (finger_data[3] >> 4);
870 		pressure = finger_data[4];
871 
872 		if (pos_x > data->max_x || pos_y > data->max_y) {
873 			dev_dbg(input->dev.parent,
874 				"[%d] x=%d y=%d over max (%d, %d)",
875 				contact_num, pos_x, pos_y,
876 				data->max_x, data->max_y);
877 			return;
878 		}
879 
880 		/*
881 		 * To avoid treating large finger as palm, let's reduce the
882 		 * width x and y per trace.
883 		 */
884 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
885 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
886 
887 		major = max(area_x, area_y);
888 		minor = min(area_x, area_y);
889 
890 		scaled_pressure = pressure + data->pressure_adjustment;
891 
892 		if (scaled_pressure > ETP_MAX_PRESSURE)
893 			scaled_pressure = ETP_MAX_PRESSURE;
894 
895 		input_mt_slot(input, contact_num);
896 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
897 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
898 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
899 		input_report_abs(input, ABS_MT_PRESSURE, scaled_pressure);
900 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
901 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
902 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
903 	} else {
904 		input_mt_slot(input, contact_num);
905 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
906 	}
907 }
908 
909 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
910 {
911 	struct input_dev *input = data->input;
912 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
913 	int i;
914 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
915 	u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
916 	bool contact_valid, hover_event;
917 
918 	hover_event = hover_info & 0x40;
919 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
920 		contact_valid = tp_info & (1U << (3 + i));
921 		elan_report_contact(data, i, contact_valid, finger_data);
922 
923 		if (contact_valid)
924 			finger_data += ETP_FINGER_DATA_LEN;
925 	}
926 
927 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
928 	input_report_key(input, BTN_RIGHT, tp_info & 0x02);
929 	input_report_abs(input, ABS_DISTANCE, hover_event != 0);
930 	input_mt_report_pointer_emulation(input, true);
931 	input_sync(input);
932 }
933 
934 static irqreturn_t elan_isr(int irq, void *dev_id)
935 {
936 	struct elan_tp_data *data = dev_id;
937 	struct device *dev = &data->client->dev;
938 	int error;
939 	u8 report[ETP_MAX_REPORT_LEN];
940 
941 	/*
942 	 * When device is connected to i2c bus, when all IAP page writes
943 	 * complete, the driver will receive interrupt and must read
944 	 * 0000 to confirm that IAP is finished.
945 	*/
946 	if (data->in_fw_update) {
947 		complete(&data->fw_completion);
948 		goto out;
949 	}
950 
951 	error = data->ops->get_report(data->client, report);
952 	if (error)
953 		goto out;
954 
955 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
956 		dev_err(dev, "invalid report id data (%x)\n",
957 			report[ETP_REPORT_ID_OFFSET]);
958 	else
959 		elan_report_absolute(data, report);
960 
961 out:
962 	return IRQ_HANDLED;
963 }
964 
965 /*
966  ******************************************************************
967  * Elan initialization functions
968  ******************************************************************
969  */
970 static int elan_setup_input_device(struct elan_tp_data *data)
971 {
972 	struct device *dev = &data->client->dev;
973 	struct input_dev *input;
974 	unsigned int max_width = max(data->width_x, data->width_y);
975 	unsigned int min_width = min(data->width_x, data->width_y);
976 	int error;
977 
978 	input = devm_input_allocate_device(dev);
979 	if (!input)
980 		return -ENOMEM;
981 
982 	input->name = "Elan Touchpad";
983 	input->id.bustype = BUS_I2C;
984 	input->id.vendor = ELAN_VENDOR_ID;
985 	input->id.product = data->product_id;
986 	input_set_drvdata(input, data);
987 
988 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
989 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
990 	if (error) {
991 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
992 		return error;
993 	}
994 
995 	__set_bit(EV_ABS, input->evbit);
996 	__set_bit(INPUT_PROP_POINTER, input->propbit);
997 	if (data->clickpad)
998 		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
999 	else
1000 		__set_bit(BTN_RIGHT, input->keybit);
1001 	__set_bit(BTN_LEFT, input->keybit);
1002 
1003 	/* Set up ST parameters */
1004 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
1005 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
1006 	input_abs_set_res(input, ABS_X, data->x_res);
1007 	input_abs_set_res(input, ABS_Y, data->y_res);
1008 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
1009 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
1010 	input_set_abs_params(input, ABS_DISTANCE, 0, 1, 0, 0);
1011 
1012 	/* And MT parameters */
1013 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
1014 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
1015 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
1016 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
1017 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
1018 			     ETP_MAX_PRESSURE, 0, 0);
1019 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
1020 			     ETP_FINGER_WIDTH * max_width, 0, 0);
1021 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
1022 			     ETP_FINGER_WIDTH * min_width, 0, 0);
1023 
1024 	data->input = input;
1025 
1026 	return 0;
1027 }
1028 
1029 static void elan_disable_regulator(void *_data)
1030 {
1031 	struct elan_tp_data *data = _data;
1032 
1033 	regulator_disable(data->vcc);
1034 }
1035 
1036 static void elan_remove_sysfs_groups(void *_data)
1037 {
1038 	struct elan_tp_data *data = _data;
1039 
1040 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
1041 }
1042 
1043 static int elan_probe(struct i2c_client *client,
1044 		      const struct i2c_device_id *dev_id)
1045 {
1046 	const struct elan_transport_ops *transport_ops;
1047 	struct device *dev = &client->dev;
1048 	struct elan_tp_data *data;
1049 	unsigned long irqflags;
1050 	int error;
1051 
1052 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
1053 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1054 		transport_ops = &elan_i2c_ops;
1055 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
1056 		   i2c_check_functionality(client->adapter,
1057 					   I2C_FUNC_SMBUS_BYTE_DATA |
1058 						I2C_FUNC_SMBUS_BLOCK_DATA |
1059 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
1060 		transport_ops = &elan_smbus_ops;
1061 	} else {
1062 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
1063 		return -EIO;
1064 	}
1065 
1066 	data = devm_kzalloc(dev, sizeof(struct elan_tp_data), GFP_KERNEL);
1067 	if (!data)
1068 		return -ENOMEM;
1069 
1070 	i2c_set_clientdata(client, data);
1071 
1072 	data->ops = transport_ops;
1073 	data->client = client;
1074 	init_completion(&data->fw_completion);
1075 	mutex_init(&data->sysfs_mutex);
1076 
1077 	data->vcc = devm_regulator_get(dev, "vcc");
1078 	if (IS_ERR(data->vcc)) {
1079 		error = PTR_ERR(data->vcc);
1080 		if (error != -EPROBE_DEFER)
1081 			dev_err(dev, "Failed to get 'vcc' regulator: %d\n",
1082 				error);
1083 		return error;
1084 	}
1085 
1086 	error = regulator_enable(data->vcc);
1087 	if (error) {
1088 		dev_err(dev, "Failed to enable regulator: %d\n", error);
1089 		return error;
1090 	}
1091 
1092 	error = devm_add_action(dev, elan_disable_regulator, data);
1093 	if (error) {
1094 		regulator_disable(data->vcc);
1095 		dev_err(dev, "Failed to add disable regulator action: %d\n",
1096 			error);
1097 		return error;
1098 	}
1099 
1100 	/* Make sure there is something at this address */
1101 	error = i2c_smbus_read_byte(client);
1102 	if (error < 0) {
1103 		dev_dbg(&client->dev, "nothing at this address: %d\n", error);
1104 		return -ENXIO;
1105 	}
1106 
1107 	/* Initialize the touchpad. */
1108 	error = elan_initialize(data);
1109 	if (error)
1110 		return error;
1111 
1112 	error = elan_query_device_info(data);
1113 	if (error)
1114 		return error;
1115 
1116 	error = elan_query_device_parameters(data);
1117 	if (error)
1118 		return error;
1119 
1120 	dev_info(dev,
1121 		 "Elan Touchpad: Module ID: 0x%04x, Firmware: 0x%04x, Sample: 0x%04x, IAP: 0x%04x\n",
1122 		 data->product_id,
1123 		 data->fw_version,
1124 		 data->sm_version,
1125 		 data->iap_version);
1126 
1127 	dev_dbg(dev,
1128 		"Elan Touchpad Extra Information:\n"
1129 		"    Max ABS X,Y:   %d,%d\n"
1130 		"    Width X,Y:   %d,%d\n"
1131 		"    Resolution X,Y:   %d,%d (dots/mm)\n"
1132 		"    ic type: 0x%x\n"
1133 		"    info pattern: 0x%x\n",
1134 		data->max_x, data->max_y,
1135 		data->width_x, data->width_y,
1136 		data->x_res, data->y_res,
1137 		data->ic_type, data->pattern);
1138 
1139 	/* Set up input device properties based on queried parameters. */
1140 	error = elan_setup_input_device(data);
1141 	if (error)
1142 		return error;
1143 
1144 	/*
1145 	 * Platform code (ACPI, DTS) should normally set up interrupt
1146 	 * for us, but in case it did not let's fall back to using falling
1147 	 * edge to be compatible with older Chromebooks.
1148 	 */
1149 	irqflags = irq_get_trigger_type(client->irq);
1150 	if (!irqflags)
1151 		irqflags = IRQF_TRIGGER_FALLING;
1152 
1153 	error = devm_request_threaded_irq(dev, client->irq, NULL, elan_isr,
1154 					  irqflags | IRQF_ONESHOT,
1155 					  client->name, data);
1156 	if (error) {
1157 		dev_err(dev, "cannot register irq=%d\n", client->irq);
1158 		return error;
1159 	}
1160 
1161 	error = sysfs_create_groups(&dev->kobj, elan_sysfs_groups);
1162 	if (error) {
1163 		dev_err(dev, "failed to create sysfs attributes: %d\n", error);
1164 		return error;
1165 	}
1166 
1167 	error = devm_add_action(dev, elan_remove_sysfs_groups, data);
1168 	if (error) {
1169 		elan_remove_sysfs_groups(data);
1170 		dev_err(dev, "Failed to add sysfs cleanup action: %d\n",
1171 			error);
1172 		return error;
1173 	}
1174 
1175 	error = input_register_device(data->input);
1176 	if (error) {
1177 		dev_err(dev, "failed to register input device: %d\n", error);
1178 		return error;
1179 	}
1180 
1181 	/*
1182 	 * Systems using device tree should set up wakeup via DTS,
1183 	 * the rest will configure device as wakeup source by default.
1184 	 */
1185 	if (!dev->of_node)
1186 		device_init_wakeup(dev, true);
1187 
1188 	return 0;
1189 }
1190 
1191 static int __maybe_unused elan_suspend(struct device *dev)
1192 {
1193 	struct i2c_client *client = to_i2c_client(dev);
1194 	struct elan_tp_data *data = i2c_get_clientdata(client);
1195 	int ret;
1196 
1197 	/*
1198 	 * We are taking the mutex to make sure sysfs operations are
1199 	 * complete before we attempt to bring the device into low[er]
1200 	 * power mode.
1201 	 */
1202 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1203 	if (ret)
1204 		return ret;
1205 
1206 	disable_irq(client->irq);
1207 
1208 	if (device_may_wakeup(dev)) {
1209 		ret = elan_sleep(data);
1210 		/* Enable wake from IRQ */
1211 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1212 	} else {
1213 		ret = elan_disable_power(data);
1214 	}
1215 
1216 	mutex_unlock(&data->sysfs_mutex);
1217 	return ret;
1218 }
1219 
1220 static int __maybe_unused elan_resume(struct device *dev)
1221 {
1222 	struct i2c_client *client = to_i2c_client(dev);
1223 	struct elan_tp_data *data = i2c_get_clientdata(client);
1224 	int error;
1225 
1226 	if (device_may_wakeup(dev) && data->irq_wake) {
1227 		disable_irq_wake(client->irq);
1228 		data->irq_wake = false;
1229 	}
1230 
1231 	error = elan_enable_power(data);
1232 	if (error) {
1233 		dev_err(dev, "power up when resuming failed: %d\n", error);
1234 		goto err;
1235 	}
1236 
1237 	error = elan_initialize(data);
1238 	if (error)
1239 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1240 
1241 err:
1242 	enable_irq(data->client->irq);
1243 	return error;
1244 }
1245 
1246 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1247 
1248 static const struct i2c_device_id elan_id[] = {
1249 	{ DRIVER_NAME, 0 },
1250 	{ },
1251 };
1252 MODULE_DEVICE_TABLE(i2c, elan_id);
1253 
1254 #ifdef CONFIG_ACPI
1255 static const struct acpi_device_id elan_acpi_id[] = {
1256 	{ "ELAN0000", 0 },
1257 	{ "ELAN0100", 0 },
1258 	{ "ELAN0600", 0 },
1259 	{ "ELAN0602", 0 },
1260 	{ "ELAN0605", 0 },
1261 	{ "ELAN0608", 0 },
1262 	{ "ELAN0609", 0 },
1263 	{ "ELAN060B", 0 },
1264 	{ "ELAN060C", 0 },
1265 	{ "ELAN0611", 0 },
1266 	{ "ELAN1000", 0 },
1267 	{ }
1268 };
1269 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1270 #endif
1271 
1272 #ifdef CONFIG_OF
1273 static const struct of_device_id elan_of_match[] = {
1274 	{ .compatible = "elan,ekth3000" },
1275 	{ /* sentinel */ }
1276 };
1277 MODULE_DEVICE_TABLE(of, elan_of_match);
1278 #endif
1279 
1280 static struct i2c_driver elan_driver = {
1281 	.driver = {
1282 		.name	= DRIVER_NAME,
1283 		.pm	= &elan_pm_ops,
1284 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1285 		.of_match_table = of_match_ptr(elan_of_match),
1286 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1287 	},
1288 	.probe		= elan_probe,
1289 	.id_table	= elan_id,
1290 };
1291 
1292 module_i2c_driver(elan_driver);
1293 
1294 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1295 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1296 MODULE_LICENSE("GPL");
1297 MODULE_VERSION(ELAN_DRIVER_VERSION);
1298