xref: /linux/drivers/input/mouse/elan_i2c_core.c (revision 507e190946297c34a27d9366b0661d5e506fdd03)
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/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	"1.6.3"
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 	u8			pattern;
82 	u16			product_id;
83 	u8			fw_version;
84 	u8			sm_version;
85 	u8			iap_version;
86 	u16			fw_checksum;
87 	int			pressure_adjustment;
88 	u8			mode;
89 	u16			ic_type;
90 	u16			fw_validpage_count;
91 	u16			fw_signature_address;
92 
93 	bool			irq_wake;
94 
95 	u8			min_baseline;
96 	u8			max_baseline;
97 	bool			baseline_ready;
98 };
99 
100 static int elan_get_fwinfo(u16 ic_type, u16 *validpage_count,
101 			   u16 *signature_address)
102 {
103 	switch (ic_type) {
104 	case 0x00:
105 	case 0x06:
106 	case 0x08:
107 		*validpage_count = 512;
108 		break;
109 	case 0x03:
110 	case 0x07:
111 	case 0x09:
112 	case 0x0A:
113 	case 0x0B:
114 	case 0x0C:
115 		*validpage_count = 768;
116 		break;
117 	case 0x0D:
118 		*validpage_count = 896;
119 		break;
120 	case 0x0E:
121 		*validpage_count = 640;
122 		break;
123 	case 0x10:
124 		*validpage_count = 1024;
125 		break;
126 	default:
127 		/* unknown ic type clear value */
128 		*validpage_count = 0;
129 		*signature_address = 0;
130 		return -ENXIO;
131 	}
132 
133 	*signature_address =
134 		(*validpage_count * ETP_FW_PAGE_SIZE) - ETP_FW_SIGNATURE_SIZE;
135 
136 	return 0;
137 }
138 
139 static int elan_enable_power(struct elan_tp_data *data)
140 {
141 	int repeat = ETP_RETRY_COUNT;
142 	int error;
143 
144 	error = regulator_enable(data->vcc);
145 	if (error) {
146 		dev_err(&data->client->dev,
147 			"failed to enable regulator: %d\n", error);
148 		return error;
149 	}
150 
151 	do {
152 		error = data->ops->power_control(data->client, true);
153 		if (error >= 0)
154 			return 0;
155 
156 		msleep(30);
157 	} while (--repeat > 0);
158 
159 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
160 	return error;
161 }
162 
163 static int elan_disable_power(struct elan_tp_data *data)
164 {
165 	int repeat = ETP_RETRY_COUNT;
166 	int error;
167 
168 	do {
169 		error = data->ops->power_control(data->client, false);
170 		if (!error) {
171 			error = regulator_disable(data->vcc);
172 			if (error) {
173 				dev_err(&data->client->dev,
174 					"failed to disable regulator: %d\n",
175 					error);
176 				/* Attempt to power the chip back up */
177 				data->ops->power_control(data->client, true);
178 				break;
179 			}
180 
181 			return 0;
182 		}
183 
184 		msleep(30);
185 	} while (--repeat > 0);
186 
187 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
188 	return error;
189 }
190 
191 static int elan_sleep(struct elan_tp_data *data)
192 {
193 	int repeat = ETP_RETRY_COUNT;
194 	int error;
195 
196 	do {
197 		error = data->ops->sleep_control(data->client, true);
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_product(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_sm_version(data->client, &data->ic_type,
216 					  &data->sm_version);
217 	if (error)
218 		return error;
219 
220 	return 0;
221 }
222 
223 static int elan_check_ASUS_special_fw(struct elan_tp_data *data)
224 {
225 	if (data->ic_type == 0x0E) {
226 		switch (data->product_id) {
227 		case 0x05 ... 0x07:
228 		case 0x09:
229 		case 0x13:
230 			return true;
231 		}
232 	} else if (data->ic_type == 0x08 && data->product_id == 0x26) {
233 		/* ASUS EeeBook X205TA */
234 		return true;
235 	}
236 
237 	return false;
238 }
239 
240 static int __elan_initialize(struct elan_tp_data *data)
241 {
242 	struct i2c_client *client = data->client;
243 	bool woken_up = false;
244 	int error;
245 
246 	error = data->ops->initialize(client);
247 	if (error) {
248 		dev_err(&client->dev, "device initialize failed: %d\n", error);
249 		return error;
250 	}
251 
252 	error = elan_query_product(data);
253 	if (error)
254 		return error;
255 
256 	/*
257 	 * Some ASUS devices were shipped with firmware that requires
258 	 * touchpads to be woken up first, before attempting to switch
259 	 * them into absolute reporting mode.
260 	 */
261 	if (elan_check_ASUS_special_fw(data)) {
262 		error = data->ops->sleep_control(client, false);
263 		if (error) {
264 			dev_err(&client->dev,
265 				"failed to wake device up: %d\n", error);
266 			return error;
267 		}
268 
269 		msleep(200);
270 		woken_up = true;
271 	}
272 
273 	data->mode |= ETP_ENABLE_ABS;
274 	error = data->ops->set_mode(client, data->mode);
275 	if (error) {
276 		dev_err(&client->dev,
277 			"failed to switch to absolute mode: %d\n", error);
278 		return error;
279 	}
280 
281 	if (!woken_up) {
282 		error = data->ops->sleep_control(client, false);
283 		if (error) {
284 			dev_err(&client->dev,
285 				"failed to wake device up: %d\n", error);
286 			return error;
287 		}
288 	}
289 
290 	return 0;
291 }
292 
293 static int elan_initialize(struct elan_tp_data *data)
294 {
295 	int repeat = ETP_RETRY_COUNT;
296 	int error;
297 
298 	do {
299 		error = __elan_initialize(data);
300 		if (!error)
301 			return 0;
302 
303 		msleep(30);
304 	} while (--repeat > 0);
305 
306 	return error;
307 }
308 
309 static int elan_query_device_info(struct elan_tp_data *data)
310 {
311 	int error;
312 	u16 ic_type;
313 
314 	error = data->ops->get_version(data->client, false, &data->fw_version);
315 	if (error)
316 		return error;
317 
318 	error = data->ops->get_checksum(data->client, false,
319 					&data->fw_checksum);
320 	if (error)
321 		return error;
322 
323 	error = data->ops->get_version(data->client, true, &data->iap_version);
324 	if (error)
325 		return error;
326 
327 	error = data->ops->get_pressure_adjustment(data->client,
328 						   &data->pressure_adjustment);
329 	if (error)
330 		return error;
331 
332 	error = data->ops->get_pattern(data->client, &data->pattern);
333 	if (error)
334 		return error;
335 
336 	if (data->pattern == 0x01)
337 		ic_type = data->ic_type;
338 	else
339 		ic_type = data->iap_version;
340 
341 	error = elan_get_fwinfo(ic_type, &data->fw_validpage_count,
342 				&data->fw_signature_address);
343 	if (error)
344 		dev_warn(&data->client->dev,
345 			 "unexpected iap version %#04x (ic type: %#04x), firmware update will not work\n",
346 			 data->iap_version, data->ic_type);
347 
348 	return 0;
349 }
350 
351 static unsigned int elan_convert_resolution(u8 val)
352 {
353 	/*
354 	 * (value from firmware) * 10 + 790 = dpi
355 	 *
356 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
357 	 * point).
358 	 */
359 
360 	return ((int)(char)val * 10 + 790) * 10 / 254;
361 }
362 
363 static int elan_query_device_parameters(struct elan_tp_data *data)
364 {
365 	unsigned int x_traces, y_traces;
366 	u8 hw_x_res, hw_y_res;
367 	int error;
368 
369 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
370 	if (error)
371 		return error;
372 
373 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
374 	if (error)
375 		return error;
376 
377 	data->width_x = data->max_x / x_traces;
378 	data->width_y = data->max_y / y_traces;
379 
380 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
381 	if (error)
382 		return error;
383 
384 	data->x_res = elan_convert_resolution(hw_x_res);
385 	data->y_res = elan_convert_resolution(hw_y_res);
386 
387 	return 0;
388 }
389 
390 /*
391  **********************************************************
392  * IAP firmware updater related routines
393  **********************************************************
394  */
395 static int elan_write_fw_block(struct elan_tp_data *data,
396 			       const u8 *page, u16 checksum, int idx)
397 {
398 	int retry = ETP_RETRY_COUNT;
399 	int error;
400 
401 	do {
402 		error = data->ops->write_fw_block(data->client,
403 						  page, checksum, idx);
404 		if (!error)
405 			return 0;
406 
407 		dev_dbg(&data->client->dev,
408 			"IAP retrying page %d (error: %d)\n", idx, error);
409 	} while (--retry > 0);
410 
411 	return error;
412 }
413 
414 static int __elan_update_firmware(struct elan_tp_data *data,
415 				  const struct firmware *fw)
416 {
417 	struct i2c_client *client = data->client;
418 	struct device *dev = &client->dev;
419 	int i, j;
420 	int error;
421 	u16 iap_start_addr;
422 	u16 boot_page_count;
423 	u16 sw_checksum = 0, fw_checksum = 0;
424 
425 	error = data->ops->prepare_fw_update(client);
426 	if (error)
427 		return error;
428 
429 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
430 
431 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
432 	for (i = boot_page_count; i < data->fw_validpage_count; i++) {
433 		u16 checksum = 0;
434 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
435 
436 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
437 			checksum += ((page[j + 1] << 8) | page[j]);
438 
439 		error = elan_write_fw_block(data, page, checksum, i);
440 		if (error) {
441 			dev_err(dev, "write page %d fail: %d\n", i, error);
442 			return error;
443 		}
444 
445 		sw_checksum += checksum;
446 	}
447 
448 	/* Wait WDT reset and power on reset */
449 	msleep(600);
450 
451 	error = data->ops->finish_fw_update(client, &data->fw_completion);
452 	if (error)
453 		return error;
454 
455 	error = data->ops->get_checksum(client, true, &fw_checksum);
456 	if (error)
457 		return error;
458 
459 	if (sw_checksum != fw_checksum) {
460 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
461 			sw_checksum, fw_checksum);
462 		return -EIO;
463 	}
464 
465 	return 0;
466 }
467 
468 static int elan_update_firmware(struct elan_tp_data *data,
469 				const struct firmware *fw)
470 {
471 	struct i2c_client *client = data->client;
472 	int retval;
473 
474 	dev_dbg(&client->dev, "Starting firmware update....\n");
475 
476 	disable_irq(client->irq);
477 	data->in_fw_update = true;
478 
479 	retval = __elan_update_firmware(data, fw);
480 	if (retval) {
481 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
482 		data->ops->iap_reset(client);
483 	} else {
484 		/* Reinitialize TP after fw is updated */
485 		elan_initialize(data);
486 		elan_query_device_info(data);
487 	}
488 
489 	data->in_fw_update = false;
490 	enable_irq(client->irq);
491 
492 	return retval;
493 }
494 
495 /*
496  *******************************************************************
497  * SYSFS attributes
498  *******************************************************************
499  */
500 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
501 					   struct device_attribute *attr,
502 					   char *buf)
503 {
504 	struct i2c_client *client = to_i2c_client(dev);
505 	struct elan_tp_data *data = i2c_get_clientdata(client);
506 
507 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
508 }
509 
510 static ssize_t elan_sysfs_read_product_id(struct device *dev,
511 					 struct device_attribute *attr,
512 					 char *buf)
513 {
514 	struct i2c_client *client = to_i2c_client(dev);
515 	struct elan_tp_data *data = i2c_get_clientdata(client);
516 
517 	return sprintf(buf, ETP_PRODUCT_ID_FORMAT_STRING "\n",
518 		       data->product_id);
519 }
520 
521 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
522 				      struct device_attribute *attr,
523 				      char *buf)
524 {
525 	struct i2c_client *client = to_i2c_client(dev);
526 	struct elan_tp_data *data = i2c_get_clientdata(client);
527 
528 	return sprintf(buf, "%d.0\n", data->fw_version);
529 }
530 
531 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
532 				      struct device_attribute *attr,
533 				      char *buf)
534 {
535 	struct i2c_client *client = to_i2c_client(dev);
536 	struct elan_tp_data *data = i2c_get_clientdata(client);
537 
538 	return sprintf(buf, "%d.0\n", data->sm_version);
539 }
540 
541 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
542 				       struct device_attribute *attr,
543 				       char *buf)
544 {
545 	struct i2c_client *client = to_i2c_client(dev);
546 	struct elan_tp_data *data = i2c_get_clientdata(client);
547 
548 	return sprintf(buf, "%d.0\n", data->iap_version);
549 }
550 
551 static ssize_t elan_sysfs_update_fw(struct device *dev,
552 				    struct device_attribute *attr,
553 				    const char *buf, size_t count)
554 {
555 	struct elan_tp_data *data = dev_get_drvdata(dev);
556 	const struct firmware *fw;
557 	char *fw_name;
558 	int error;
559 	const u8 *fw_signature;
560 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
561 
562 	if (data->fw_validpage_count == 0)
563 		return -EINVAL;
564 
565 	/* Look for a firmware with the product id appended. */
566 	fw_name = kasprintf(GFP_KERNEL, ETP_FW_NAME, data->product_id);
567 	if (!fw_name) {
568 		dev_err(dev, "failed to allocate memory for firmware name\n");
569 		return -ENOMEM;
570 	}
571 
572 	dev_info(dev, "requesting fw '%s'\n", fw_name);
573 	error = request_firmware(&fw, fw_name, dev);
574 	kfree(fw_name);
575 	if (error) {
576 		dev_err(dev, "failed to request firmware: %d\n", error);
577 		return error;
578 	}
579 
580 	/* Firmware file must match signature data */
581 	fw_signature = &fw->data[data->fw_signature_address];
582 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
583 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
584 			(int)sizeof(signature), signature,
585 			(int)sizeof(signature), fw_signature);
586 		error = -EBADF;
587 		goto out_release_fw;
588 	}
589 
590 	error = mutex_lock_interruptible(&data->sysfs_mutex);
591 	if (error)
592 		goto out_release_fw;
593 
594 	error = elan_update_firmware(data, fw);
595 
596 	mutex_unlock(&data->sysfs_mutex);
597 
598 out_release_fw:
599 	release_firmware(fw);
600 	return error ?: count;
601 }
602 
603 static ssize_t calibrate_store(struct device *dev,
604 			       struct device_attribute *attr,
605 			       const char *buf, size_t count)
606 {
607 	struct i2c_client *client = to_i2c_client(dev);
608 	struct elan_tp_data *data = i2c_get_clientdata(client);
609 	int tries = 20;
610 	int retval;
611 	int error;
612 	u8 val[3];
613 
614 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
615 	if (retval)
616 		return retval;
617 
618 	disable_irq(client->irq);
619 
620 	data->mode |= ETP_ENABLE_CALIBRATE;
621 	retval = data->ops->set_mode(client, data->mode);
622 	if (retval) {
623 		dev_err(dev, "failed to enable calibration mode: %d\n",
624 			retval);
625 		goto out;
626 	}
627 
628 	retval = data->ops->calibrate(client);
629 	if (retval) {
630 		dev_err(dev, "failed to start calibration: %d\n",
631 			retval);
632 		goto out_disable_calibrate;
633 	}
634 
635 	val[0] = 0xff;
636 	do {
637 		/* Wait 250ms before checking if calibration has completed. */
638 		msleep(250);
639 
640 		retval = data->ops->calibrate_result(client, val);
641 		if (retval)
642 			dev_err(dev, "failed to check calibration result: %d\n",
643 				retval);
644 		else if (val[0] == 0)
645 			break; /* calibration done */
646 
647 	} while (--tries);
648 
649 	if (tries == 0) {
650 		dev_err(dev, "failed to calibrate. Timeout.\n");
651 		retval = -ETIMEDOUT;
652 	}
653 
654 out_disable_calibrate:
655 	data->mode &= ~ETP_ENABLE_CALIBRATE;
656 	error = data->ops->set_mode(data->client, data->mode);
657 	if (error) {
658 		dev_err(dev, "failed to disable calibration mode: %d\n",
659 			error);
660 		if (!retval)
661 			retval = error;
662 	}
663 out:
664 	enable_irq(client->irq);
665 	mutex_unlock(&data->sysfs_mutex);
666 	return retval ?: count;
667 }
668 
669 static ssize_t elan_sysfs_read_mode(struct device *dev,
670 				    struct device_attribute *attr,
671 				    char *buf)
672 {
673 	struct i2c_client *client = to_i2c_client(dev);
674 	struct elan_tp_data *data = i2c_get_clientdata(client);
675 	int error;
676 	enum tp_mode mode;
677 
678 	error = mutex_lock_interruptible(&data->sysfs_mutex);
679 	if (error)
680 		return error;
681 
682 	error = data->ops->iap_get_mode(data->client, &mode);
683 
684 	mutex_unlock(&data->sysfs_mutex);
685 
686 	if (error)
687 		return error;
688 
689 	return sprintf(buf, "%d\n", (int)mode);
690 }
691 
692 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
693 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
694 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
695 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
696 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
697 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
698 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
699 
700 static DEVICE_ATTR_WO(calibrate);
701 
702 static struct attribute *elan_sysfs_entries[] = {
703 	&dev_attr_product_id.attr,
704 	&dev_attr_firmware_version.attr,
705 	&dev_attr_sample_version.attr,
706 	&dev_attr_iap_version.attr,
707 	&dev_attr_fw_checksum.attr,
708 	&dev_attr_calibrate.attr,
709 	&dev_attr_mode.attr,
710 	&dev_attr_update_fw.attr,
711 	NULL,
712 };
713 
714 static const struct attribute_group elan_sysfs_group = {
715 	.attrs = elan_sysfs_entries,
716 };
717 
718 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
719 			     const char *buf, size_t count)
720 {
721 	struct i2c_client *client = to_i2c_client(dev);
722 	struct elan_tp_data *data = i2c_get_clientdata(client);
723 	int error;
724 	int retval;
725 
726 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
727 	if (retval)
728 		return retval;
729 
730 	disable_irq(client->irq);
731 
732 	data->baseline_ready = false;
733 
734 	data->mode |= ETP_ENABLE_CALIBRATE;
735 	retval = data->ops->set_mode(data->client, data->mode);
736 	if (retval) {
737 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
738 			retval);
739 		goto out;
740 	}
741 
742 	msleep(250);
743 
744 	retval = data->ops->get_baseline_data(data->client, true,
745 					      &data->max_baseline);
746 	if (retval) {
747 		dev_err(dev, "Failed to read max baseline form device: %d\n",
748 			retval);
749 		goto out_disable_calibrate;
750 	}
751 
752 	retval = data->ops->get_baseline_data(data->client, false,
753 					      &data->min_baseline);
754 	if (retval) {
755 		dev_err(dev, "Failed to read min baseline form device: %d\n",
756 			retval);
757 		goto out_disable_calibrate;
758 	}
759 
760 	data->baseline_ready = true;
761 
762 out_disable_calibrate:
763 	data->mode &= ~ETP_ENABLE_CALIBRATE;
764 	error = data->ops->set_mode(data->client, data->mode);
765 	if (error) {
766 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
767 			error);
768 		if (!retval)
769 			retval = error;
770 	}
771 out:
772 	enable_irq(client->irq);
773 	mutex_unlock(&data->sysfs_mutex);
774 	return retval ?: count;
775 }
776 
777 static ssize_t min_show(struct device *dev,
778 			struct device_attribute *attr, char *buf)
779 {
780 	struct i2c_client *client = to_i2c_client(dev);
781 	struct elan_tp_data *data = i2c_get_clientdata(client);
782 	int retval;
783 
784 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
785 	if (retval)
786 		return retval;
787 
788 	if (!data->baseline_ready) {
789 		retval = -ENODATA;
790 		goto out;
791 	}
792 
793 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
794 
795 out:
796 	mutex_unlock(&data->sysfs_mutex);
797 	return retval;
798 }
799 
800 static ssize_t max_show(struct device *dev,
801 			struct device_attribute *attr, char *buf)
802 {
803 	struct i2c_client *client = to_i2c_client(dev);
804 	struct elan_tp_data *data = i2c_get_clientdata(client);
805 	int retval;
806 
807 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
808 	if (retval)
809 		return retval;
810 
811 	if (!data->baseline_ready) {
812 		retval = -ENODATA;
813 		goto out;
814 	}
815 
816 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
817 
818 out:
819 	mutex_unlock(&data->sysfs_mutex);
820 	return retval;
821 }
822 
823 
824 static DEVICE_ATTR_WO(acquire);
825 static DEVICE_ATTR_RO(min);
826 static DEVICE_ATTR_RO(max);
827 
828 static struct attribute *elan_baseline_sysfs_entries[] = {
829 	&dev_attr_acquire.attr,
830 	&dev_attr_min.attr,
831 	&dev_attr_max.attr,
832 	NULL,
833 };
834 
835 static const struct attribute_group elan_baseline_sysfs_group = {
836 	.name = "baseline",
837 	.attrs = elan_baseline_sysfs_entries,
838 };
839 
840 static const struct attribute_group *elan_sysfs_groups[] = {
841 	&elan_sysfs_group,
842 	&elan_baseline_sysfs_group,
843 	NULL
844 };
845 
846 /*
847  ******************************************************************
848  * Elan isr functions
849  ******************************************************************
850  */
851 static void elan_report_contact(struct elan_tp_data *data,
852 				int contact_num, bool contact_valid,
853 				u8 *finger_data)
854 {
855 	struct input_dev *input = data->input;
856 	unsigned int pos_x, pos_y;
857 	unsigned int pressure, mk_x, mk_y;
858 	unsigned int area_x, area_y, major, minor;
859 	unsigned int scaled_pressure;
860 
861 	if (contact_valid) {
862 		pos_x = ((finger_data[0] & 0xf0) << 4) |
863 						finger_data[1];
864 		pos_y = ((finger_data[0] & 0x0f) << 8) |
865 						finger_data[2];
866 		mk_x = (finger_data[3] & 0x0f);
867 		mk_y = (finger_data[3] >> 4);
868 		pressure = finger_data[4];
869 
870 		if (pos_x > data->max_x || pos_y > data->max_y) {
871 			dev_dbg(input->dev.parent,
872 				"[%d] x=%d y=%d over max (%d, %d)",
873 				contact_num, pos_x, pos_y,
874 				data->max_x, data->max_y);
875 			return;
876 		}
877 
878 		/*
879 		 * To avoid treating large finger as palm, let's reduce the
880 		 * width x and y per trace.
881 		 */
882 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
883 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
884 
885 		major = max(area_x, area_y);
886 		minor = min(area_x, area_y);
887 
888 		scaled_pressure = pressure + data->pressure_adjustment;
889 
890 		if (scaled_pressure > ETP_MAX_PRESSURE)
891 			scaled_pressure = ETP_MAX_PRESSURE;
892 
893 		input_mt_slot(input, contact_num);
894 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
895 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
896 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
897 		input_report_abs(input, ABS_MT_PRESSURE, scaled_pressure);
898 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
899 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
900 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
901 	} else {
902 		input_mt_slot(input, contact_num);
903 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
904 	}
905 }
906 
907 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
908 {
909 	struct input_dev *input = data->input;
910 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
911 	int i;
912 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
913 	u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
914 	bool contact_valid, hover_event;
915 
916 	hover_event = hover_info & 0x40;
917 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
918 		contact_valid = tp_info & (1U << (3 + i));
919 		elan_report_contact(data, i, contact_valid, finger_data);
920 
921 		if (contact_valid)
922 			finger_data += ETP_FINGER_DATA_LEN;
923 	}
924 
925 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
926 	input_report_abs(input, ABS_DISTANCE, hover_event != 0);
927 	input_mt_report_pointer_emulation(input, true);
928 	input_sync(input);
929 }
930 
931 static irqreturn_t elan_isr(int irq, void *dev_id)
932 {
933 	struct elan_tp_data *data = dev_id;
934 	struct device *dev = &data->client->dev;
935 	int error;
936 	u8 report[ETP_MAX_REPORT_LEN];
937 
938 	/*
939 	 * When device is connected to i2c bus, when all IAP page writes
940 	 * complete, the driver will receive interrupt and must read
941 	 * 0000 to confirm that IAP is finished.
942 	*/
943 	if (data->in_fw_update) {
944 		complete(&data->fw_completion);
945 		goto out;
946 	}
947 
948 	error = data->ops->get_report(data->client, report);
949 	if (error)
950 		goto out;
951 
952 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
953 		dev_err(dev, "invalid report id data (%x)\n",
954 			report[ETP_REPORT_ID_OFFSET]);
955 	else
956 		elan_report_absolute(data, report);
957 
958 out:
959 	return IRQ_HANDLED;
960 }
961 
962 /*
963  ******************************************************************
964  * Elan initialization functions
965  ******************************************************************
966  */
967 static int elan_setup_input_device(struct elan_tp_data *data)
968 {
969 	struct device *dev = &data->client->dev;
970 	struct input_dev *input;
971 	unsigned int max_width = max(data->width_x, data->width_y);
972 	unsigned int min_width = min(data->width_x, data->width_y);
973 	int error;
974 
975 	input = devm_input_allocate_device(dev);
976 	if (!input)
977 		return -ENOMEM;
978 
979 	input->name = "Elan Touchpad";
980 	input->id.bustype = BUS_I2C;
981 	input->id.vendor = ELAN_VENDOR_ID;
982 	input->id.product = data->product_id;
983 	input_set_drvdata(input, data);
984 
985 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
986 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
987 	if (error) {
988 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
989 		return error;
990 	}
991 
992 	__set_bit(EV_ABS, input->evbit);
993 	__set_bit(INPUT_PROP_POINTER, input->propbit);
994 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
995 	__set_bit(BTN_LEFT, input->keybit);
996 
997 	/* Set up ST parameters */
998 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
999 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
1000 	input_abs_set_res(input, ABS_X, data->x_res);
1001 	input_abs_set_res(input, ABS_Y, data->y_res);
1002 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
1003 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
1004 	input_set_abs_params(input, ABS_DISTANCE, 0, 1, 0, 0);
1005 
1006 	/* And MT parameters */
1007 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
1008 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
1009 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
1010 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
1011 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
1012 			     ETP_MAX_PRESSURE, 0, 0);
1013 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
1014 			     ETP_FINGER_WIDTH * max_width, 0, 0);
1015 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
1016 			     ETP_FINGER_WIDTH * min_width, 0, 0);
1017 
1018 	data->input = input;
1019 
1020 	return 0;
1021 }
1022 
1023 static void elan_disable_regulator(void *_data)
1024 {
1025 	struct elan_tp_data *data = _data;
1026 
1027 	regulator_disable(data->vcc);
1028 }
1029 
1030 static void elan_remove_sysfs_groups(void *_data)
1031 {
1032 	struct elan_tp_data *data = _data;
1033 
1034 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
1035 }
1036 
1037 static int elan_probe(struct i2c_client *client,
1038 		      const struct i2c_device_id *dev_id)
1039 {
1040 	const struct elan_transport_ops *transport_ops;
1041 	struct device *dev = &client->dev;
1042 	struct elan_tp_data *data;
1043 	unsigned long irqflags;
1044 	int error;
1045 
1046 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
1047 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1048 		transport_ops = &elan_i2c_ops;
1049 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
1050 		   i2c_check_functionality(client->adapter,
1051 					   I2C_FUNC_SMBUS_BYTE_DATA |
1052 						I2C_FUNC_SMBUS_BLOCK_DATA |
1053 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
1054 		transport_ops = &elan_smbus_ops;
1055 	} else {
1056 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
1057 		return -EIO;
1058 	}
1059 
1060 	data = devm_kzalloc(dev, sizeof(struct elan_tp_data), GFP_KERNEL);
1061 	if (!data)
1062 		return -ENOMEM;
1063 
1064 	i2c_set_clientdata(client, data);
1065 
1066 	data->ops = transport_ops;
1067 	data->client = client;
1068 	init_completion(&data->fw_completion);
1069 	mutex_init(&data->sysfs_mutex);
1070 
1071 	data->vcc = devm_regulator_get(dev, "vcc");
1072 	if (IS_ERR(data->vcc)) {
1073 		error = PTR_ERR(data->vcc);
1074 		if (error != -EPROBE_DEFER)
1075 			dev_err(dev, "Failed to get 'vcc' regulator: %d\n",
1076 				error);
1077 		return error;
1078 	}
1079 
1080 	error = regulator_enable(data->vcc);
1081 	if (error) {
1082 		dev_err(dev, "Failed to enable regulator: %d\n", error);
1083 		return error;
1084 	}
1085 
1086 	error = devm_add_action(dev, elan_disable_regulator, data);
1087 	if (error) {
1088 		regulator_disable(data->vcc);
1089 		dev_err(dev, "Failed to add disable regulator action: %d\n",
1090 			error);
1091 		return error;
1092 	}
1093 
1094 	/* Make sure there is something at this address */
1095 	error = i2c_smbus_read_byte(client);
1096 	if (error < 0) {
1097 		dev_dbg(&client->dev, "nothing at this address: %d\n", error);
1098 		return -ENXIO;
1099 	}
1100 
1101 	/* Initialize the touchpad. */
1102 	error = elan_initialize(data);
1103 	if (error)
1104 		return error;
1105 
1106 	error = elan_query_device_info(data);
1107 	if (error)
1108 		return error;
1109 
1110 	error = elan_query_device_parameters(data);
1111 	if (error)
1112 		return error;
1113 
1114 	dev_info(dev,
1115 		 "Elan Touchpad: Module ID: 0x%04x, Firmware: 0x%04x, Sample: 0x%04x, IAP: 0x%04x\n",
1116 		 data->product_id,
1117 		 data->fw_version,
1118 		 data->sm_version,
1119 		 data->iap_version);
1120 
1121 	dev_dbg(dev,
1122 		"Elan Touchpad Extra Information:\n"
1123 		"    Max ABS X,Y:   %d,%d\n"
1124 		"    Width X,Y:   %d,%d\n"
1125 		"    Resolution X,Y:   %d,%d (dots/mm)\n"
1126 		"    ic type: 0x%x\n"
1127 		"    info pattern: 0x%x\n",
1128 		data->max_x, data->max_y,
1129 		data->width_x, data->width_y,
1130 		data->x_res, data->y_res,
1131 		data->ic_type, data->pattern);
1132 
1133 	/* Set up input device properties based on queried parameters. */
1134 	error = elan_setup_input_device(data);
1135 	if (error)
1136 		return error;
1137 
1138 	/*
1139 	 * Systems using device tree should set up interrupt via DTS,
1140 	 * the rest will use the default falling edge interrupts.
1141 	 */
1142 	irqflags = dev->of_node ? 0 : IRQF_TRIGGER_FALLING;
1143 
1144 	error = devm_request_threaded_irq(dev, client->irq, NULL, elan_isr,
1145 					  irqflags | IRQF_ONESHOT,
1146 					  client->name, data);
1147 	if (error) {
1148 		dev_err(dev, "cannot register irq=%d\n", client->irq);
1149 		return error;
1150 	}
1151 
1152 	error = sysfs_create_groups(&dev->kobj, elan_sysfs_groups);
1153 	if (error) {
1154 		dev_err(dev, "failed to create sysfs attributes: %d\n", error);
1155 		return error;
1156 	}
1157 
1158 	error = devm_add_action(dev, elan_remove_sysfs_groups, data);
1159 	if (error) {
1160 		elan_remove_sysfs_groups(data);
1161 		dev_err(dev, "Failed to add sysfs cleanup action: %d\n",
1162 			error);
1163 		return error;
1164 	}
1165 
1166 	error = input_register_device(data->input);
1167 	if (error) {
1168 		dev_err(dev, "failed to register input device: %d\n", error);
1169 		return error;
1170 	}
1171 
1172 	/*
1173 	 * Systems using device tree should set up wakeup via DTS,
1174 	 * the rest will configure device as wakeup source by default.
1175 	 */
1176 	if (!dev->of_node)
1177 		device_init_wakeup(dev, true);
1178 
1179 	return 0;
1180 }
1181 
1182 static int __maybe_unused elan_suspend(struct device *dev)
1183 {
1184 	struct i2c_client *client = to_i2c_client(dev);
1185 	struct elan_tp_data *data = i2c_get_clientdata(client);
1186 	int ret;
1187 
1188 	/*
1189 	 * We are taking the mutex to make sure sysfs operations are
1190 	 * complete before we attempt to bring the device into low[er]
1191 	 * power mode.
1192 	 */
1193 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1194 	if (ret)
1195 		return ret;
1196 
1197 	disable_irq(client->irq);
1198 
1199 	if (device_may_wakeup(dev)) {
1200 		ret = elan_sleep(data);
1201 		/* Enable wake from IRQ */
1202 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1203 	} else {
1204 		ret = elan_disable_power(data);
1205 	}
1206 
1207 	mutex_unlock(&data->sysfs_mutex);
1208 	return ret;
1209 }
1210 
1211 static int __maybe_unused elan_resume(struct device *dev)
1212 {
1213 	struct i2c_client *client = to_i2c_client(dev);
1214 	struct elan_tp_data *data = i2c_get_clientdata(client);
1215 	int error;
1216 
1217 	if (device_may_wakeup(dev) && data->irq_wake) {
1218 		disable_irq_wake(client->irq);
1219 		data->irq_wake = false;
1220 	}
1221 
1222 	error = elan_enable_power(data);
1223 	if (error) {
1224 		dev_err(dev, "power up when resuming failed: %d\n", error);
1225 		goto err;
1226 	}
1227 
1228 	error = elan_initialize(data);
1229 	if (error)
1230 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1231 
1232 err:
1233 	enable_irq(data->client->irq);
1234 	return error;
1235 }
1236 
1237 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1238 
1239 static const struct i2c_device_id elan_id[] = {
1240 	{ DRIVER_NAME, 0 },
1241 	{ },
1242 };
1243 MODULE_DEVICE_TABLE(i2c, elan_id);
1244 
1245 #ifdef CONFIG_ACPI
1246 static const struct acpi_device_id elan_acpi_id[] = {
1247 	{ "ELAN0000", 0 },
1248 	{ "ELAN0100", 0 },
1249 	{ "ELAN0600", 0 },
1250 	{ "ELAN0605", 0 },
1251 	{ "ELAN1000", 0 },
1252 	{ }
1253 };
1254 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1255 #endif
1256 
1257 #ifdef CONFIG_OF
1258 static const struct of_device_id elan_of_match[] = {
1259 	{ .compatible = "elan,ekth3000" },
1260 	{ /* sentinel */ }
1261 };
1262 MODULE_DEVICE_TABLE(of, elan_of_match);
1263 #endif
1264 
1265 static struct i2c_driver elan_driver = {
1266 	.driver = {
1267 		.name	= DRIVER_NAME,
1268 		.pm	= &elan_pm_ops,
1269 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1270 		.of_match_table = of_match_ptr(elan_of_match),
1271 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1272 	},
1273 	.probe		= elan_probe,
1274 	.id_table	= elan_id,
1275 };
1276 
1277 module_i2c_driver(elan_driver);
1278 
1279 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1280 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1281 MODULE_LICENSE("GPL");
1282 MODULE_VERSION(ELAN_DRIVER_VERSION);
1283