xref: /linux/drivers/input/mouse/elan_i2c_core.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
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: 1.6.2
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/module.h>
30 #include <linux/slab.h>
31 #include <linux/kernel.h>
32 #include <linux/sched.h>
33 #include <linux/input.h>
34 #include <linux/uaccess.h>
35 #include <linux/jiffies.h>
36 #include <linux/completion.h>
37 #include <linux/of.h>
38 #include <linux/regulator/consumer.h>
39 #include <asm/unaligned.h>
40 
41 #include "elan_i2c.h"
42 
43 #define DRIVER_NAME		"elan_i2c"
44 #define ELAN_DRIVER_VERSION	"1.6.2"
45 #define ELAN_VENDOR_ID		0x04f3
46 #define ETP_MAX_PRESSURE	255
47 #define ETP_FWIDTH_REDUCE	90
48 #define ETP_FINGER_WIDTH	15
49 #define ETP_RETRY_COUNT		3
50 
51 #define ETP_MAX_FINGERS		5
52 #define ETP_FINGER_DATA_LEN	5
53 #define ETP_REPORT_ID		0x5D
54 #define ETP_REPORT_ID_OFFSET	2
55 #define ETP_TOUCH_INFO_OFFSET	3
56 #define ETP_FINGER_DATA_OFFSET	4
57 #define ETP_HOVER_INFO_OFFSET	30
58 #define ETP_MAX_REPORT_LEN	34
59 
60 /* The main device structure */
61 struct elan_tp_data {
62 	struct i2c_client	*client;
63 	struct input_dev	*input;
64 	struct regulator	*vcc;
65 
66 	const struct elan_transport_ops *ops;
67 
68 	/* for fw update */
69 	struct completion	fw_completion;
70 	bool			in_fw_update;
71 
72 	struct mutex		sysfs_mutex;
73 
74 	unsigned int		max_x;
75 	unsigned int		max_y;
76 	unsigned int		width_x;
77 	unsigned int		width_y;
78 	unsigned int		x_res;
79 	unsigned int		y_res;
80 
81 	u16			product_id;
82 	u8			fw_version;
83 	u8			sm_version;
84 	u8			iap_version;
85 	u16			fw_checksum;
86 	int			pressure_adjustment;
87 	u8			mode;
88 	u8			ic_type;
89 	u16			fw_validpage_count;
90 	u16			fw_signature_address;
91 
92 	bool			irq_wake;
93 
94 	u8			min_baseline;
95 	u8			max_baseline;
96 	bool			baseline_ready;
97 };
98 
99 static int elan_get_fwinfo(u8 iap_version, u16 *validpage_count,
100 			   u16 *signature_address)
101 {
102 	switch (iap_version) {
103 	case 0x00:
104 	case 0x06:
105 	case 0x08:
106 		*validpage_count = 512;
107 		break;
108 	case 0x03:
109 	case 0x07:
110 	case 0x09:
111 	case 0x0A:
112 	case 0x0B:
113 	case 0x0C:
114 		*validpage_count = 768;
115 		break;
116 	case 0x0D:
117 		*validpage_count = 896;
118 		break;
119 	case 0x0E:
120 		*validpage_count = 640;
121 		break;
122 	default:
123 		/* unknown ic type clear value */
124 		*validpage_count = 0;
125 		*signature_address = 0;
126 		return -ENXIO;
127 	}
128 
129 	*signature_address =
130 		(*validpage_count * ETP_FW_PAGE_SIZE) - ETP_FW_SIGNATURE_SIZE;
131 
132 	return 0;
133 }
134 
135 static int elan_enable_power(struct elan_tp_data *data)
136 {
137 	int repeat = ETP_RETRY_COUNT;
138 	int error;
139 
140 	error = regulator_enable(data->vcc);
141 	if (error) {
142 		dev_err(&data->client->dev,
143 			"failed to enable regulator: %d\n", error);
144 		return error;
145 	}
146 
147 	do {
148 		error = data->ops->power_control(data->client, true);
149 		if (error >= 0)
150 			return 0;
151 
152 		msleep(30);
153 	} while (--repeat > 0);
154 
155 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
156 	return error;
157 }
158 
159 static int elan_disable_power(struct elan_tp_data *data)
160 {
161 	int repeat = ETP_RETRY_COUNT;
162 	int error;
163 
164 	do {
165 		error = data->ops->power_control(data->client, false);
166 		if (!error) {
167 			error = regulator_disable(data->vcc);
168 			if (error) {
169 				dev_err(&data->client->dev,
170 					"failed to disable regulator: %d\n",
171 					error);
172 				/* Attempt to power the chip back up */
173 				data->ops->power_control(data->client, true);
174 				break;
175 			}
176 
177 			return 0;
178 		}
179 
180 		msleep(30);
181 	} while (--repeat > 0);
182 
183 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
184 	return error;
185 }
186 
187 static int elan_sleep(struct elan_tp_data *data)
188 {
189 	int repeat = ETP_RETRY_COUNT;
190 	int error;
191 
192 	do {
193 		error = data->ops->sleep_control(data->client, true);
194 		if (!error)
195 			return 0;
196 
197 		msleep(30);
198 	} while (--repeat > 0);
199 
200 	return error;
201 }
202 
203 static int elan_query_product(struct elan_tp_data *data)
204 {
205 	int error;
206 
207 	error = data->ops->get_product_id(data->client, &data->product_id);
208 	if (error)
209 		return error;
210 
211 	error = data->ops->get_sm_version(data->client, &data->ic_type,
212 					  &data->sm_version);
213 	if (error)
214 		return error;
215 
216 	return 0;
217 }
218 
219 static int elan_check_ASUS_special_fw(struct elan_tp_data *data)
220 {
221 	if (data->ic_type == 0x0E) {
222 		switch (data->product_id) {
223 		case 0x05 ... 0x07:
224 		case 0x09:
225 		case 0x13:
226 			return true;
227 		}
228 	} else if (data->ic_type == 0x08 && data->product_id == 0x26) {
229 		/* ASUS EeeBook X205TA */
230 		return true;
231 	}
232 
233 	return false;
234 }
235 
236 static int __elan_initialize(struct elan_tp_data *data)
237 {
238 	struct i2c_client *client = data->client;
239 	bool woken_up = false;
240 	int error;
241 
242 	error = data->ops->initialize(client);
243 	if (error) {
244 		dev_err(&client->dev, "device initialize failed: %d\n", error);
245 		return error;
246 	}
247 
248 	error = elan_query_product(data);
249 	if (error)
250 		return error;
251 
252 	/*
253 	 * Some ASUS devices were shipped with firmware that requires
254 	 * touchpads to be woken up first, before attempting to switch
255 	 * them into absolute reporting mode.
256 	 */
257 	if (elan_check_ASUS_special_fw(data)) {
258 		error = data->ops->sleep_control(client, false);
259 		if (error) {
260 			dev_err(&client->dev,
261 				"failed to wake device up: %d\n", error);
262 			return error;
263 		}
264 
265 		msleep(200);
266 		woken_up = true;
267 	}
268 
269 	data->mode |= ETP_ENABLE_ABS;
270 	error = data->ops->set_mode(client, data->mode);
271 	if (error) {
272 		dev_err(&client->dev,
273 			"failed to switch to absolute mode: %d\n", error);
274 		return error;
275 	}
276 
277 	if (!woken_up) {
278 		error = data->ops->sleep_control(client, false);
279 		if (error) {
280 			dev_err(&client->dev,
281 				"failed to wake device up: %d\n", error);
282 			return error;
283 		}
284 	}
285 
286 	return 0;
287 }
288 
289 static int elan_initialize(struct elan_tp_data *data)
290 {
291 	int repeat = ETP_RETRY_COUNT;
292 	int error;
293 
294 	do {
295 		error = __elan_initialize(data);
296 		if (!error)
297 			return 0;
298 
299 		msleep(30);
300 	} while (--repeat > 0);
301 
302 	return error;
303 }
304 
305 static int elan_query_device_info(struct elan_tp_data *data)
306 {
307 	int error;
308 
309 	error = data->ops->get_version(data->client, false, &data->fw_version);
310 	if (error)
311 		return error;
312 
313 	error = data->ops->get_checksum(data->client, false,
314 					&data->fw_checksum);
315 	if (error)
316 		return error;
317 
318 	error = data->ops->get_version(data->client, true, &data->iap_version);
319 	if (error)
320 		return error;
321 
322 	error = data->ops->get_pressure_adjustment(data->client,
323 						   &data->pressure_adjustment);
324 	if (error)
325 		return error;
326 
327 	error = elan_get_fwinfo(data->iap_version, &data->fw_validpage_count,
328 				&data->fw_signature_address);
329 	if (error)
330 		dev_warn(&data->client->dev,
331 			 "unexpected iap version %#04x (ic type: %#04x), firmware update will not work\n",
332 			 data->iap_version, data->ic_type);
333 
334 	return 0;
335 }
336 
337 static unsigned int elan_convert_resolution(u8 val)
338 {
339 	/*
340 	 * (value from firmware) * 10 + 790 = dpi
341 	 *
342 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
343 	 * point).
344 	 */
345 
346 	return ((int)(char)val * 10 + 790) * 10 / 254;
347 }
348 
349 static int elan_query_device_parameters(struct elan_tp_data *data)
350 {
351 	unsigned int x_traces, y_traces;
352 	u8 hw_x_res, hw_y_res;
353 	int error;
354 
355 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
356 	if (error)
357 		return error;
358 
359 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
360 	if (error)
361 		return error;
362 
363 	data->width_x = data->max_x / x_traces;
364 	data->width_y = data->max_y / y_traces;
365 
366 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
367 	if (error)
368 		return error;
369 
370 	data->x_res = elan_convert_resolution(hw_x_res);
371 	data->y_res = elan_convert_resolution(hw_y_res);
372 
373 	return 0;
374 }
375 
376 /*
377  **********************************************************
378  * IAP firmware updater related routines
379  **********************************************************
380  */
381 static int elan_write_fw_block(struct elan_tp_data *data,
382 			       const u8 *page, u16 checksum, int idx)
383 {
384 	int retry = ETP_RETRY_COUNT;
385 	int error;
386 
387 	do {
388 		error = data->ops->write_fw_block(data->client,
389 						  page, checksum, idx);
390 		if (!error)
391 			return 0;
392 
393 		dev_dbg(&data->client->dev,
394 			"IAP retrying page %d (error: %d)\n", idx, error);
395 	} while (--retry > 0);
396 
397 	return error;
398 }
399 
400 static int __elan_update_firmware(struct elan_tp_data *data,
401 				  const struct firmware *fw)
402 {
403 	struct i2c_client *client = data->client;
404 	struct device *dev = &client->dev;
405 	int i, j;
406 	int error;
407 	u16 iap_start_addr;
408 	u16 boot_page_count;
409 	u16 sw_checksum = 0, fw_checksum = 0;
410 
411 	error = data->ops->prepare_fw_update(client);
412 	if (error)
413 		return error;
414 
415 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
416 
417 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
418 	for (i = boot_page_count; i < data->fw_validpage_count; i++) {
419 		u16 checksum = 0;
420 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
421 
422 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
423 			checksum += ((page[j + 1] << 8) | page[j]);
424 
425 		error = elan_write_fw_block(data, page, checksum, i);
426 		if (error) {
427 			dev_err(dev, "write page %d fail: %d\n", i, error);
428 			return error;
429 		}
430 
431 		sw_checksum += checksum;
432 	}
433 
434 	/* Wait WDT reset and power on reset */
435 	msleep(600);
436 
437 	error = data->ops->finish_fw_update(client, &data->fw_completion);
438 	if (error)
439 		return error;
440 
441 	error = data->ops->get_checksum(client, true, &fw_checksum);
442 	if (error)
443 		return error;
444 
445 	if (sw_checksum != fw_checksum) {
446 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
447 			sw_checksum, fw_checksum);
448 		return -EIO;
449 	}
450 
451 	return 0;
452 }
453 
454 static int elan_update_firmware(struct elan_tp_data *data,
455 				const struct firmware *fw)
456 {
457 	struct i2c_client *client = data->client;
458 	int retval;
459 
460 	dev_dbg(&client->dev, "Starting firmware update....\n");
461 
462 	disable_irq(client->irq);
463 	data->in_fw_update = true;
464 
465 	retval = __elan_update_firmware(data, fw);
466 	if (retval) {
467 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
468 		data->ops->iap_reset(client);
469 	} else {
470 		/* Reinitialize TP after fw is updated */
471 		elan_initialize(data);
472 		elan_query_device_info(data);
473 	}
474 
475 	data->in_fw_update = false;
476 	enable_irq(client->irq);
477 
478 	return retval;
479 }
480 
481 /*
482  *******************************************************************
483  * SYSFS attributes
484  *******************************************************************
485  */
486 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
487 					   struct device_attribute *attr,
488 					   char *buf)
489 {
490 	struct i2c_client *client = to_i2c_client(dev);
491 	struct elan_tp_data *data = i2c_get_clientdata(client);
492 
493 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
494 }
495 
496 static ssize_t elan_sysfs_read_product_id(struct device *dev,
497 					 struct device_attribute *attr,
498 					 char *buf)
499 {
500 	struct i2c_client *client = to_i2c_client(dev);
501 	struct elan_tp_data *data = i2c_get_clientdata(client);
502 
503 	return sprintf(buf, ETP_PRODUCT_ID_FORMAT_STRING "\n",
504 		       data->product_id);
505 }
506 
507 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
508 				      struct device_attribute *attr,
509 				      char *buf)
510 {
511 	struct i2c_client *client = to_i2c_client(dev);
512 	struct elan_tp_data *data = i2c_get_clientdata(client);
513 
514 	return sprintf(buf, "%d.0\n", data->fw_version);
515 }
516 
517 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
518 				      struct device_attribute *attr,
519 				      char *buf)
520 {
521 	struct i2c_client *client = to_i2c_client(dev);
522 	struct elan_tp_data *data = i2c_get_clientdata(client);
523 
524 	return sprintf(buf, "%d.0\n", data->sm_version);
525 }
526 
527 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
528 				       struct device_attribute *attr,
529 				       char *buf)
530 {
531 	struct i2c_client *client = to_i2c_client(dev);
532 	struct elan_tp_data *data = i2c_get_clientdata(client);
533 
534 	return sprintf(buf, "%d.0\n", data->iap_version);
535 }
536 
537 static ssize_t elan_sysfs_update_fw(struct device *dev,
538 				    struct device_attribute *attr,
539 				    const char *buf, size_t count)
540 {
541 	struct elan_tp_data *data = dev_get_drvdata(dev);
542 	const struct firmware *fw;
543 	char *fw_name;
544 	int error;
545 	const u8 *fw_signature;
546 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
547 
548 	if (data->fw_validpage_count == 0)
549 		return -EINVAL;
550 
551 	/* Look for a firmware with the product id appended. */
552 	fw_name = kasprintf(GFP_KERNEL, ETP_FW_NAME, data->product_id);
553 	if (!fw_name) {
554 		dev_err(dev, "failed to allocate memory for firmware name\n");
555 		return -ENOMEM;
556 	}
557 
558 	dev_info(dev, "requesting fw '%s'\n", fw_name);
559 	error = request_firmware(&fw, fw_name, dev);
560 	kfree(fw_name);
561 	if (error) {
562 		dev_err(dev, "failed to request firmware: %d\n", error);
563 		return error;
564 	}
565 
566 	/* Firmware file must match signature data */
567 	fw_signature = &fw->data[data->fw_signature_address];
568 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
569 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
570 			(int)sizeof(signature), signature,
571 			(int)sizeof(signature), fw_signature);
572 		error = -EBADF;
573 		goto out_release_fw;
574 	}
575 
576 	error = mutex_lock_interruptible(&data->sysfs_mutex);
577 	if (error)
578 		goto out_release_fw;
579 
580 	error = elan_update_firmware(data, fw);
581 
582 	mutex_unlock(&data->sysfs_mutex);
583 
584 out_release_fw:
585 	release_firmware(fw);
586 	return error ?: count;
587 }
588 
589 static ssize_t calibrate_store(struct device *dev,
590 			       struct device_attribute *attr,
591 			       const char *buf, size_t count)
592 {
593 	struct i2c_client *client = to_i2c_client(dev);
594 	struct elan_tp_data *data = i2c_get_clientdata(client);
595 	int tries = 20;
596 	int retval;
597 	int error;
598 	u8 val[3];
599 
600 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
601 	if (retval)
602 		return retval;
603 
604 	disable_irq(client->irq);
605 
606 	data->mode |= ETP_ENABLE_CALIBRATE;
607 	retval = data->ops->set_mode(client, data->mode);
608 	if (retval) {
609 		dev_err(dev, "failed to enable calibration mode: %d\n",
610 			retval);
611 		goto out;
612 	}
613 
614 	retval = data->ops->calibrate(client);
615 	if (retval) {
616 		dev_err(dev, "failed to start calibration: %d\n",
617 			retval);
618 		goto out_disable_calibrate;
619 	}
620 
621 	val[0] = 0xff;
622 	do {
623 		/* Wait 250ms before checking if calibration has completed. */
624 		msleep(250);
625 
626 		retval = data->ops->calibrate_result(client, val);
627 		if (retval)
628 			dev_err(dev, "failed to check calibration result: %d\n",
629 				retval);
630 		else if (val[0] == 0)
631 			break; /* calibration done */
632 
633 	} while (--tries);
634 
635 	if (tries == 0) {
636 		dev_err(dev, "failed to calibrate. Timeout.\n");
637 		retval = -ETIMEDOUT;
638 	}
639 
640 out_disable_calibrate:
641 	data->mode &= ~ETP_ENABLE_CALIBRATE;
642 	error = data->ops->set_mode(data->client, data->mode);
643 	if (error) {
644 		dev_err(dev, "failed to disable calibration mode: %d\n",
645 			error);
646 		if (!retval)
647 			retval = error;
648 	}
649 out:
650 	enable_irq(client->irq);
651 	mutex_unlock(&data->sysfs_mutex);
652 	return retval ?: count;
653 }
654 
655 static ssize_t elan_sysfs_read_mode(struct device *dev,
656 				    struct device_attribute *attr,
657 				    char *buf)
658 {
659 	struct i2c_client *client = to_i2c_client(dev);
660 	struct elan_tp_data *data = i2c_get_clientdata(client);
661 	int error;
662 	enum tp_mode mode;
663 
664 	error = mutex_lock_interruptible(&data->sysfs_mutex);
665 	if (error)
666 		return error;
667 
668 	error = data->ops->iap_get_mode(data->client, &mode);
669 
670 	mutex_unlock(&data->sysfs_mutex);
671 
672 	if (error)
673 		return error;
674 
675 	return sprintf(buf, "%d\n", (int)mode);
676 }
677 
678 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
679 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
680 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
681 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
682 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
683 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
684 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
685 
686 static DEVICE_ATTR_WO(calibrate);
687 
688 static struct attribute *elan_sysfs_entries[] = {
689 	&dev_attr_product_id.attr,
690 	&dev_attr_firmware_version.attr,
691 	&dev_attr_sample_version.attr,
692 	&dev_attr_iap_version.attr,
693 	&dev_attr_fw_checksum.attr,
694 	&dev_attr_calibrate.attr,
695 	&dev_attr_mode.attr,
696 	&dev_attr_update_fw.attr,
697 	NULL,
698 };
699 
700 static const struct attribute_group elan_sysfs_group = {
701 	.attrs = elan_sysfs_entries,
702 };
703 
704 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
705 			     const char *buf, size_t count)
706 {
707 	struct i2c_client *client = to_i2c_client(dev);
708 	struct elan_tp_data *data = i2c_get_clientdata(client);
709 	int error;
710 	int retval;
711 
712 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
713 	if (retval)
714 		return retval;
715 
716 	disable_irq(client->irq);
717 
718 	data->baseline_ready = false;
719 
720 	data->mode |= ETP_ENABLE_CALIBRATE;
721 	retval = data->ops->set_mode(data->client, data->mode);
722 	if (retval) {
723 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
724 			retval);
725 		goto out;
726 	}
727 
728 	msleep(250);
729 
730 	retval = data->ops->get_baseline_data(data->client, true,
731 					      &data->max_baseline);
732 	if (retval) {
733 		dev_err(dev, "Failed to read max baseline form device: %d\n",
734 			retval);
735 		goto out_disable_calibrate;
736 	}
737 
738 	retval = data->ops->get_baseline_data(data->client, false,
739 					      &data->min_baseline);
740 	if (retval) {
741 		dev_err(dev, "Failed to read min baseline form device: %d\n",
742 			retval);
743 		goto out_disable_calibrate;
744 	}
745 
746 	data->baseline_ready = true;
747 
748 out_disable_calibrate:
749 	data->mode &= ~ETP_ENABLE_CALIBRATE;
750 	error = data->ops->set_mode(data->client, data->mode);
751 	if (error) {
752 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
753 			error);
754 		if (!retval)
755 			retval = error;
756 	}
757 out:
758 	enable_irq(client->irq);
759 	mutex_unlock(&data->sysfs_mutex);
760 	return retval ?: count;
761 }
762 
763 static ssize_t min_show(struct device *dev,
764 			struct device_attribute *attr, char *buf)
765 {
766 	struct i2c_client *client = to_i2c_client(dev);
767 	struct elan_tp_data *data = i2c_get_clientdata(client);
768 	int retval;
769 
770 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
771 	if (retval)
772 		return retval;
773 
774 	if (!data->baseline_ready) {
775 		retval = -ENODATA;
776 		goto out;
777 	}
778 
779 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
780 
781 out:
782 	mutex_unlock(&data->sysfs_mutex);
783 	return retval;
784 }
785 
786 static ssize_t max_show(struct device *dev,
787 			struct device_attribute *attr, char *buf)
788 {
789 	struct i2c_client *client = to_i2c_client(dev);
790 	struct elan_tp_data *data = i2c_get_clientdata(client);
791 	int retval;
792 
793 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
794 	if (retval)
795 		return retval;
796 
797 	if (!data->baseline_ready) {
798 		retval = -ENODATA;
799 		goto out;
800 	}
801 
802 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
803 
804 out:
805 	mutex_unlock(&data->sysfs_mutex);
806 	return retval;
807 }
808 
809 
810 static DEVICE_ATTR_WO(acquire);
811 static DEVICE_ATTR_RO(min);
812 static DEVICE_ATTR_RO(max);
813 
814 static struct attribute *elan_baseline_sysfs_entries[] = {
815 	&dev_attr_acquire.attr,
816 	&dev_attr_min.attr,
817 	&dev_attr_max.attr,
818 	NULL,
819 };
820 
821 static const struct attribute_group elan_baseline_sysfs_group = {
822 	.name = "baseline",
823 	.attrs = elan_baseline_sysfs_entries,
824 };
825 
826 static const struct attribute_group *elan_sysfs_groups[] = {
827 	&elan_sysfs_group,
828 	&elan_baseline_sysfs_group,
829 	NULL
830 };
831 
832 /*
833  ******************************************************************
834  * Elan isr functions
835  ******************************************************************
836  */
837 static void elan_report_contact(struct elan_tp_data *data,
838 				int contact_num, bool contact_valid,
839 				u8 *finger_data)
840 {
841 	struct input_dev *input = data->input;
842 	unsigned int pos_x, pos_y;
843 	unsigned int pressure, mk_x, mk_y;
844 	unsigned int area_x, area_y, major, minor;
845 	unsigned int scaled_pressure;
846 
847 	if (contact_valid) {
848 		pos_x = ((finger_data[0] & 0xf0) << 4) |
849 						finger_data[1];
850 		pos_y = ((finger_data[0] & 0x0f) << 8) |
851 						finger_data[2];
852 		mk_x = (finger_data[3] & 0x0f);
853 		mk_y = (finger_data[3] >> 4);
854 		pressure = finger_data[4];
855 
856 		if (pos_x > data->max_x || pos_y > data->max_y) {
857 			dev_dbg(input->dev.parent,
858 				"[%d] x=%d y=%d over max (%d, %d)",
859 				contact_num, pos_x, pos_y,
860 				data->max_x, data->max_y);
861 			return;
862 		}
863 
864 		/*
865 		 * To avoid treating large finger as palm, let's reduce the
866 		 * width x and y per trace.
867 		 */
868 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
869 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
870 
871 		major = max(area_x, area_y);
872 		minor = min(area_x, area_y);
873 
874 		scaled_pressure = pressure + data->pressure_adjustment;
875 
876 		if (scaled_pressure > ETP_MAX_PRESSURE)
877 			scaled_pressure = ETP_MAX_PRESSURE;
878 
879 		input_mt_slot(input, contact_num);
880 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
881 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
882 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
883 		input_report_abs(input, ABS_MT_PRESSURE, scaled_pressure);
884 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
885 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
886 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
887 	} else {
888 		input_mt_slot(input, contact_num);
889 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
890 	}
891 }
892 
893 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
894 {
895 	struct input_dev *input = data->input;
896 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
897 	int i;
898 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
899 	u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
900 	bool contact_valid, hover_event;
901 
902 	hover_event = hover_info & 0x40;
903 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
904 		contact_valid = tp_info & (1U << (3 + i));
905 		elan_report_contact(data, i, contact_valid, finger_data);
906 
907 		if (contact_valid)
908 			finger_data += ETP_FINGER_DATA_LEN;
909 	}
910 
911 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
912 	input_report_abs(input, ABS_DISTANCE, hover_event != 0);
913 	input_mt_report_pointer_emulation(input, true);
914 	input_sync(input);
915 }
916 
917 static irqreturn_t elan_isr(int irq, void *dev_id)
918 {
919 	struct elan_tp_data *data = dev_id;
920 	struct device *dev = &data->client->dev;
921 	int error;
922 	u8 report[ETP_MAX_REPORT_LEN];
923 
924 	/*
925 	 * When device is connected to i2c bus, when all IAP page writes
926 	 * complete, the driver will receive interrupt and must read
927 	 * 0000 to confirm that IAP is finished.
928 	*/
929 	if (data->in_fw_update) {
930 		complete(&data->fw_completion);
931 		goto out;
932 	}
933 
934 	error = data->ops->get_report(data->client, report);
935 	if (error)
936 		goto out;
937 
938 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
939 		dev_err(dev, "invalid report id data (%x)\n",
940 			report[ETP_REPORT_ID_OFFSET]);
941 	else
942 		elan_report_absolute(data, report);
943 
944 out:
945 	return IRQ_HANDLED;
946 }
947 
948 /*
949  ******************************************************************
950  * Elan initialization functions
951  ******************************************************************
952  */
953 static int elan_setup_input_device(struct elan_tp_data *data)
954 {
955 	struct device *dev = &data->client->dev;
956 	struct input_dev *input;
957 	unsigned int max_width = max(data->width_x, data->width_y);
958 	unsigned int min_width = min(data->width_x, data->width_y);
959 	int error;
960 
961 	input = devm_input_allocate_device(dev);
962 	if (!input)
963 		return -ENOMEM;
964 
965 	input->name = "Elan Touchpad";
966 	input->id.bustype = BUS_I2C;
967 	input->id.vendor = ELAN_VENDOR_ID;
968 	input->id.product = data->product_id;
969 	input_set_drvdata(input, data);
970 
971 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
972 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
973 	if (error) {
974 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
975 		return error;
976 	}
977 
978 	__set_bit(EV_ABS, input->evbit);
979 	__set_bit(INPUT_PROP_POINTER, input->propbit);
980 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
981 	__set_bit(BTN_LEFT, input->keybit);
982 
983 	/* Set up ST parameters */
984 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
985 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
986 	input_abs_set_res(input, ABS_X, data->x_res);
987 	input_abs_set_res(input, ABS_Y, data->y_res);
988 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
989 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
990 	input_set_abs_params(input, ABS_DISTANCE, 0, 1, 0, 0);
991 
992 	/* And MT parameters */
993 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
994 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
995 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
996 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
997 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
998 			     ETP_MAX_PRESSURE, 0, 0);
999 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
1000 			     ETP_FINGER_WIDTH * max_width, 0, 0);
1001 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
1002 			     ETP_FINGER_WIDTH * min_width, 0, 0);
1003 
1004 	data->input = input;
1005 
1006 	return 0;
1007 }
1008 
1009 static void elan_disable_regulator(void *_data)
1010 {
1011 	struct elan_tp_data *data = _data;
1012 
1013 	regulator_disable(data->vcc);
1014 }
1015 
1016 static void elan_remove_sysfs_groups(void *_data)
1017 {
1018 	struct elan_tp_data *data = _data;
1019 
1020 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
1021 }
1022 
1023 static int elan_probe(struct i2c_client *client,
1024 		      const struct i2c_device_id *dev_id)
1025 {
1026 	const struct elan_transport_ops *transport_ops;
1027 	struct device *dev = &client->dev;
1028 	struct elan_tp_data *data;
1029 	unsigned long irqflags;
1030 	int error;
1031 
1032 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
1033 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1034 		transport_ops = &elan_i2c_ops;
1035 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
1036 		   i2c_check_functionality(client->adapter,
1037 					   I2C_FUNC_SMBUS_BYTE_DATA |
1038 						I2C_FUNC_SMBUS_BLOCK_DATA |
1039 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
1040 		transport_ops = &elan_smbus_ops;
1041 	} else {
1042 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
1043 		return -EIO;
1044 	}
1045 
1046 	data = devm_kzalloc(dev, sizeof(struct elan_tp_data), GFP_KERNEL);
1047 	if (!data)
1048 		return -ENOMEM;
1049 
1050 	i2c_set_clientdata(client, data);
1051 
1052 	data->ops = transport_ops;
1053 	data->client = client;
1054 	init_completion(&data->fw_completion);
1055 	mutex_init(&data->sysfs_mutex);
1056 
1057 	data->vcc = devm_regulator_get(dev, "vcc");
1058 	if (IS_ERR(data->vcc)) {
1059 		error = PTR_ERR(data->vcc);
1060 		if (error != -EPROBE_DEFER)
1061 			dev_err(dev, "Failed to get 'vcc' regulator: %d\n",
1062 				error);
1063 		return error;
1064 	}
1065 
1066 	error = regulator_enable(data->vcc);
1067 	if (error) {
1068 		dev_err(dev, "Failed to enable regulator: %d\n", error);
1069 		return error;
1070 	}
1071 
1072 	error = devm_add_action(dev, elan_disable_regulator, data);
1073 	if (error) {
1074 		regulator_disable(data->vcc);
1075 		dev_err(dev, "Failed to add disable regulator action: %d\n",
1076 			error);
1077 		return error;
1078 	}
1079 
1080 	/* Initialize the touchpad. */
1081 	error = elan_initialize(data);
1082 	if (error)
1083 		return error;
1084 
1085 	error = elan_query_device_info(data);
1086 	if (error)
1087 		return error;
1088 
1089 	error = elan_query_device_parameters(data);
1090 	if (error)
1091 		return error;
1092 
1093 	dev_info(dev,
1094 		 "Elan Touchpad: Module ID: 0x%04x, Firmware: 0x%04x, Sample: 0x%04x, IAP: 0x%04x\n",
1095 		 data->product_id,
1096 		 data->fw_version,
1097 		 data->sm_version,
1098 		 data->iap_version);
1099 
1100 	dev_dbg(dev,
1101 		"Elan Touchpad Extra Information:\n"
1102 		"    Max ABS X,Y:   %d,%d\n"
1103 		"    Width X,Y:   %d,%d\n"
1104 		"    Resolution X,Y:   %d,%d (dots/mm)\n",
1105 		data->max_x, data->max_y,
1106 		data->width_x, data->width_y,
1107 		data->x_res, data->y_res);
1108 
1109 	/* Set up input device properties based on queried parameters. */
1110 	error = elan_setup_input_device(data);
1111 	if (error)
1112 		return error;
1113 
1114 	/*
1115 	 * Systems using device tree should set up interrupt via DTS,
1116 	 * the rest will use the default falling edge interrupts.
1117 	 */
1118 	irqflags = dev->of_node ? 0 : IRQF_TRIGGER_FALLING;
1119 
1120 	error = devm_request_threaded_irq(dev, client->irq, NULL, elan_isr,
1121 					  irqflags | IRQF_ONESHOT,
1122 					  client->name, data);
1123 	if (error) {
1124 		dev_err(dev, "cannot register irq=%d\n", client->irq);
1125 		return error;
1126 	}
1127 
1128 	error = sysfs_create_groups(&dev->kobj, elan_sysfs_groups);
1129 	if (error) {
1130 		dev_err(dev, "failed to create sysfs attributes: %d\n", error);
1131 		return error;
1132 	}
1133 
1134 	error = devm_add_action(dev, elan_remove_sysfs_groups, data);
1135 	if (error) {
1136 		elan_remove_sysfs_groups(data);
1137 		dev_err(dev, "Failed to add sysfs cleanup action: %d\n",
1138 			error);
1139 		return error;
1140 	}
1141 
1142 	error = input_register_device(data->input);
1143 	if (error) {
1144 		dev_err(dev, "failed to register input device: %d\n", error);
1145 		return error;
1146 	}
1147 
1148 	/*
1149 	 * Systems using device tree should set up wakeup via DTS,
1150 	 * the rest will configure device as wakeup source by default.
1151 	 */
1152 	if (!dev->of_node)
1153 		device_init_wakeup(dev, true);
1154 
1155 	return 0;
1156 }
1157 
1158 static int __maybe_unused elan_suspend(struct device *dev)
1159 {
1160 	struct i2c_client *client = to_i2c_client(dev);
1161 	struct elan_tp_data *data = i2c_get_clientdata(client);
1162 	int ret;
1163 
1164 	/*
1165 	 * We are taking the mutex to make sure sysfs operations are
1166 	 * complete before we attempt to bring the device into low[er]
1167 	 * power mode.
1168 	 */
1169 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1170 	if (ret)
1171 		return ret;
1172 
1173 	disable_irq(client->irq);
1174 
1175 	if (device_may_wakeup(dev)) {
1176 		ret = elan_sleep(data);
1177 		/* Enable wake from IRQ */
1178 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1179 	} else {
1180 		ret = elan_disable_power(data);
1181 	}
1182 
1183 	mutex_unlock(&data->sysfs_mutex);
1184 	return ret;
1185 }
1186 
1187 static int __maybe_unused elan_resume(struct device *dev)
1188 {
1189 	struct i2c_client *client = to_i2c_client(dev);
1190 	struct elan_tp_data *data = i2c_get_clientdata(client);
1191 	int error;
1192 
1193 	if (device_may_wakeup(dev) && data->irq_wake) {
1194 		disable_irq_wake(client->irq);
1195 		data->irq_wake = false;
1196 	}
1197 
1198 	error = elan_enable_power(data);
1199 	if (error) {
1200 		dev_err(dev, "power up when resuming failed: %d\n", error);
1201 		goto err;
1202 	}
1203 
1204 	error = elan_initialize(data);
1205 	if (error)
1206 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1207 
1208 err:
1209 	enable_irq(data->client->irq);
1210 	return error;
1211 }
1212 
1213 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1214 
1215 static const struct i2c_device_id elan_id[] = {
1216 	{ DRIVER_NAME, 0 },
1217 	{ },
1218 };
1219 MODULE_DEVICE_TABLE(i2c, elan_id);
1220 
1221 #ifdef CONFIG_ACPI
1222 static const struct acpi_device_id elan_acpi_id[] = {
1223 	{ "ELAN0000", 0 },
1224 	{ "ELAN0100", 0 },
1225 	{ "ELAN0600", 0 },
1226 	{ "ELAN0605", 0 },
1227 	{ "ELAN1000", 0 },
1228 	{ }
1229 };
1230 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1231 #endif
1232 
1233 #ifdef CONFIG_OF
1234 static const struct of_device_id elan_of_match[] = {
1235 	{ .compatible = "elan,ekth3000" },
1236 	{ /* sentinel */ }
1237 };
1238 MODULE_DEVICE_TABLE(of, elan_of_match);
1239 #endif
1240 
1241 static struct i2c_driver elan_driver = {
1242 	.driver = {
1243 		.name	= DRIVER_NAME,
1244 		.pm	= &elan_pm_ops,
1245 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1246 		.of_match_table = of_match_ptr(elan_of_match),
1247 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1248 	},
1249 	.probe		= elan_probe,
1250 	.id_table	= elan_id,
1251 };
1252 
1253 module_i2c_driver(elan_driver);
1254 
1255 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1256 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1257 MODULE_LICENSE("GPL");
1258 MODULE_VERSION(ELAN_DRIVER_VERSION);
1259