xref: /linux/drivers/input/mouse/elan_i2c_core.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Elan I2C/SMBus Touchpad driver
3  *
4  * Copyright (c) 2013 ELAN Microelectronics Corp.
5  *
6  * Author: 林政維 (Duson Lin) <dusonlin@emc.com.tw>
7  * Version: 1.6.0
8  *
9  * Based on cyapa driver:
10  * copyright (c) 2011-2012 Cypress Semiconductor, Inc.
11  * copyright (c) 2011-2012 Google, Inc.
12  *
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms of the GNU General Public License version 2 as published
15  * by the Free Software Foundation.
16  *
17  * Trademarks are the property of their respective owners.
18  */
19 
20 #include <linux/acpi.h>
21 #include <linux/delay.h>
22 #include <linux/device.h>
23 #include <linux/firmware.h>
24 #include <linux/i2c.h>
25 #include <linux/init.h>
26 #include <linux/input/mt.h>
27 #include <linux/interrupt.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/kernel.h>
31 #include <linux/sched.h>
32 #include <linux/input.h>
33 #include <linux/uaccess.h>
34 #include <linux/jiffies.h>
35 #include <linux/completion.h>
36 #include <linux/of.h>
37 #include <linux/regulator/consumer.h>
38 #include <asm/unaligned.h>
39 
40 #include "elan_i2c.h"
41 
42 #define DRIVER_NAME		"elan_i2c"
43 #define ELAN_DRIVER_VERSION	"1.6.1"
44 #define ETP_MAX_PRESSURE	255
45 #define ETP_FWIDTH_REDUCE	90
46 #define ETP_FINGER_WIDTH	15
47 #define ETP_RETRY_COUNT		3
48 
49 #define ETP_MAX_FINGERS		5
50 #define ETP_FINGER_DATA_LEN	5
51 #define ETP_REPORT_ID		0x5D
52 #define ETP_REPORT_ID_OFFSET	2
53 #define ETP_TOUCH_INFO_OFFSET	3
54 #define ETP_FINGER_DATA_OFFSET	4
55 #define ETP_HOVER_INFO_OFFSET	30
56 #define ETP_MAX_REPORT_LEN	34
57 
58 /* The main device structure */
59 struct elan_tp_data {
60 	struct i2c_client	*client;
61 	struct input_dev	*input;
62 	struct regulator	*vcc;
63 
64 	const struct elan_transport_ops *ops;
65 
66 	/* for fw update */
67 	struct completion	fw_completion;
68 	bool			in_fw_update;
69 
70 	struct mutex		sysfs_mutex;
71 
72 	unsigned int		max_x;
73 	unsigned int		max_y;
74 	unsigned int		width_x;
75 	unsigned int		width_y;
76 	unsigned int		x_res;
77 	unsigned int		y_res;
78 
79 	u16			product_id;
80 	u8			fw_version;
81 	u8			sm_version;
82 	u8			iap_version;
83 	u16			fw_checksum;
84 	int			pressure_adjustment;
85 	u8			mode;
86 	u8			ic_type;
87 	u16			fw_validpage_count;
88 	u16			fw_signature_address;
89 
90 	bool			irq_wake;
91 
92 	u8			min_baseline;
93 	u8			max_baseline;
94 	bool			baseline_ready;
95 };
96 
97 static int elan_get_fwinfo(u8 iap_version, u16 *validpage_count,
98 			   u16 *signature_address)
99 {
100 	switch (iap_version) {
101 	case 0x00:
102 	case 0x06:
103 	case 0x08:
104 		*validpage_count = 512;
105 		break;
106 	case 0x03:
107 	case 0x07:
108 	case 0x09:
109 	case 0x0A:
110 	case 0x0B:
111 	case 0x0C:
112 		*validpage_count = 768;
113 		break;
114 	case 0x0D:
115 		*validpage_count = 896;
116 		break;
117 	case 0x0E:
118 		*validpage_count = 640;
119 		break;
120 	default:
121 		/* unknown ic type clear value */
122 		*validpage_count = 0;
123 		*signature_address = 0;
124 		return -ENXIO;
125 	}
126 
127 	*signature_address =
128 		(*validpage_count * ETP_FW_PAGE_SIZE) - ETP_FW_SIGNATURE_SIZE;
129 
130 	return 0;
131 }
132 
133 static int elan_enable_power(struct elan_tp_data *data)
134 {
135 	int repeat = ETP_RETRY_COUNT;
136 	int error;
137 
138 	error = regulator_enable(data->vcc);
139 	if (error) {
140 		dev_err(&data->client->dev,
141 			"failed to enable regulator: %d\n", error);
142 		return error;
143 	}
144 
145 	do {
146 		error = data->ops->power_control(data->client, true);
147 		if (error >= 0)
148 			return 0;
149 
150 		msleep(30);
151 	} while (--repeat > 0);
152 
153 	dev_err(&data->client->dev, "failed to enable power: %d\n", error);
154 	return error;
155 }
156 
157 static int elan_disable_power(struct elan_tp_data *data)
158 {
159 	int repeat = ETP_RETRY_COUNT;
160 	int error;
161 
162 	do {
163 		error = data->ops->power_control(data->client, false);
164 		if (!error) {
165 			error = regulator_disable(data->vcc);
166 			if (error) {
167 				dev_err(&data->client->dev,
168 					"failed to disable regulator: %d\n",
169 					error);
170 				/* Attempt to power the chip back up */
171 				data->ops->power_control(data->client, true);
172 				break;
173 			}
174 
175 			return 0;
176 		}
177 
178 		msleep(30);
179 	} while (--repeat > 0);
180 
181 	dev_err(&data->client->dev, "failed to disable power: %d\n", error);
182 	return error;
183 }
184 
185 static int elan_sleep(struct elan_tp_data *data)
186 {
187 	int repeat = ETP_RETRY_COUNT;
188 	int error;
189 
190 	do {
191 		error = data->ops->sleep_control(data->client, true);
192 		if (!error)
193 			return 0;
194 
195 		msleep(30);
196 	} while (--repeat > 0);
197 
198 	return error;
199 }
200 
201 static int __elan_initialize(struct elan_tp_data *data)
202 {
203 	struct i2c_client *client = data->client;
204 	int error;
205 
206 	error = data->ops->initialize(client);
207 	if (error) {
208 		dev_err(&client->dev, "device initialize failed: %d\n", error);
209 		return error;
210 	}
211 
212 	data->mode |= ETP_ENABLE_ABS;
213 	error = data->ops->set_mode(client, data->mode);
214 	if (error) {
215 		dev_err(&client->dev,
216 			"failed to switch to absolute mode: %d\n", error);
217 		return error;
218 	}
219 
220 	error = data->ops->sleep_control(client, false);
221 	if (error) {
222 		dev_err(&client->dev,
223 			"failed to wake device up: %d\n", error);
224 		return error;
225 	}
226 
227 	return 0;
228 }
229 
230 static int elan_initialize(struct elan_tp_data *data)
231 {
232 	int repeat = ETP_RETRY_COUNT;
233 	int error;
234 
235 	do {
236 		error = __elan_initialize(data);
237 		if (!error)
238 			return 0;
239 
240 		msleep(30);
241 	} while (--repeat > 0);
242 
243 	return error;
244 }
245 
246 static int elan_query_device_info(struct elan_tp_data *data)
247 {
248 	int error;
249 
250 	error = data->ops->get_product_id(data->client, &data->product_id);
251 	if (error)
252 		return error;
253 
254 	error = data->ops->get_version(data->client, false, &data->fw_version);
255 	if (error)
256 		return error;
257 
258 	error = data->ops->get_checksum(data->client, false,
259 					&data->fw_checksum);
260 	if (error)
261 		return error;
262 
263 	error = data->ops->get_sm_version(data->client, &data->ic_type,
264 					  &data->sm_version);
265 	if (error)
266 		return error;
267 
268 	error = data->ops->get_version(data->client, true, &data->iap_version);
269 	if (error)
270 		return error;
271 
272 	error = data->ops->get_pressure_adjustment(data->client,
273 						   &data->pressure_adjustment);
274 	if (error)
275 		return error;
276 
277 	error = elan_get_fwinfo(data->iap_version, &data->fw_validpage_count,
278 				&data->fw_signature_address);
279 	if (error)
280 		dev_warn(&data->client->dev,
281 			 "unexpected iap version %#04x (ic type: %#04x), firmware update will not work\n",
282 			 data->iap_version, data->ic_type);
283 
284 	return 0;
285 }
286 
287 static unsigned int elan_convert_resolution(u8 val)
288 {
289 	/*
290 	 * (value from firmware) * 10 + 790 = dpi
291 	 *
292 	 * We also have to convert dpi to dots/mm (*10/254 to avoid floating
293 	 * point).
294 	 */
295 
296 	return ((int)(char)val * 10 + 790) * 10 / 254;
297 }
298 
299 static int elan_query_device_parameters(struct elan_tp_data *data)
300 {
301 	unsigned int x_traces, y_traces;
302 	u8 hw_x_res, hw_y_res;
303 	int error;
304 
305 	error = data->ops->get_max(data->client, &data->max_x, &data->max_y);
306 	if (error)
307 		return error;
308 
309 	error = data->ops->get_num_traces(data->client, &x_traces, &y_traces);
310 	if (error)
311 		return error;
312 
313 	data->width_x = data->max_x / x_traces;
314 	data->width_y = data->max_y / y_traces;
315 
316 	error = data->ops->get_resolution(data->client, &hw_x_res, &hw_y_res);
317 	if (error)
318 		return error;
319 
320 	data->x_res = elan_convert_resolution(hw_x_res);
321 	data->y_res = elan_convert_resolution(hw_y_res);
322 
323 	return 0;
324 }
325 
326 /*
327  **********************************************************
328  * IAP firmware updater related routines
329  **********************************************************
330  */
331 static int elan_write_fw_block(struct elan_tp_data *data,
332 			       const u8 *page, u16 checksum, int idx)
333 {
334 	int retry = ETP_RETRY_COUNT;
335 	int error;
336 
337 	do {
338 		error = data->ops->write_fw_block(data->client,
339 						  page, checksum, idx);
340 		if (!error)
341 			return 0;
342 
343 		dev_dbg(&data->client->dev,
344 			"IAP retrying page %d (error: %d)\n", idx, error);
345 	} while (--retry > 0);
346 
347 	return error;
348 }
349 
350 static int __elan_update_firmware(struct elan_tp_data *data,
351 				  const struct firmware *fw)
352 {
353 	struct i2c_client *client = data->client;
354 	struct device *dev = &client->dev;
355 	int i, j;
356 	int error;
357 	u16 iap_start_addr;
358 	u16 boot_page_count;
359 	u16 sw_checksum = 0, fw_checksum = 0;
360 
361 	error = data->ops->prepare_fw_update(client);
362 	if (error)
363 		return error;
364 
365 	iap_start_addr = get_unaligned_le16(&fw->data[ETP_IAP_START_ADDR * 2]);
366 
367 	boot_page_count = (iap_start_addr * 2) / ETP_FW_PAGE_SIZE;
368 	for (i = boot_page_count; i < data->fw_validpage_count; i++) {
369 		u16 checksum = 0;
370 		const u8 *page = &fw->data[i * ETP_FW_PAGE_SIZE];
371 
372 		for (j = 0; j < ETP_FW_PAGE_SIZE; j += 2)
373 			checksum += ((page[j + 1] << 8) | page[j]);
374 
375 		error = elan_write_fw_block(data, page, checksum, i);
376 		if (error) {
377 			dev_err(dev, "write page %d fail: %d\n", i, error);
378 			return error;
379 		}
380 
381 		sw_checksum += checksum;
382 	}
383 
384 	/* Wait WDT reset and power on reset */
385 	msleep(600);
386 
387 	error = data->ops->finish_fw_update(client, &data->fw_completion);
388 	if (error)
389 		return error;
390 
391 	error = data->ops->get_checksum(client, true, &fw_checksum);
392 	if (error)
393 		return error;
394 
395 	if (sw_checksum != fw_checksum) {
396 		dev_err(dev, "checksum diff sw=[%04X], fw=[%04X]\n",
397 			sw_checksum, fw_checksum);
398 		return -EIO;
399 	}
400 
401 	return 0;
402 }
403 
404 static int elan_update_firmware(struct elan_tp_data *data,
405 				const struct firmware *fw)
406 {
407 	struct i2c_client *client = data->client;
408 	int retval;
409 
410 	dev_dbg(&client->dev, "Starting firmware update....\n");
411 
412 	disable_irq(client->irq);
413 	data->in_fw_update = true;
414 
415 	retval = __elan_update_firmware(data, fw);
416 	if (retval) {
417 		dev_err(&client->dev, "firmware update failed: %d\n", retval);
418 		data->ops->iap_reset(client);
419 	} else {
420 		/* Reinitialize TP after fw is updated */
421 		elan_initialize(data);
422 		elan_query_device_info(data);
423 	}
424 
425 	data->in_fw_update = false;
426 	enable_irq(client->irq);
427 
428 	return retval;
429 }
430 
431 /*
432  *******************************************************************
433  * SYSFS attributes
434  *******************************************************************
435  */
436 static ssize_t elan_sysfs_read_fw_checksum(struct device *dev,
437 					   struct device_attribute *attr,
438 					   char *buf)
439 {
440 	struct i2c_client *client = to_i2c_client(dev);
441 	struct elan_tp_data *data = i2c_get_clientdata(client);
442 
443 	return sprintf(buf, "0x%04x\n", data->fw_checksum);
444 }
445 
446 static ssize_t elan_sysfs_read_product_id(struct device *dev,
447 					 struct device_attribute *attr,
448 					 char *buf)
449 {
450 	struct i2c_client *client = to_i2c_client(dev);
451 	struct elan_tp_data *data = i2c_get_clientdata(client);
452 
453 	return sprintf(buf, ETP_PRODUCT_ID_FORMAT_STRING "\n",
454 		       data->product_id);
455 }
456 
457 static ssize_t elan_sysfs_read_fw_ver(struct device *dev,
458 				      struct device_attribute *attr,
459 				      char *buf)
460 {
461 	struct i2c_client *client = to_i2c_client(dev);
462 	struct elan_tp_data *data = i2c_get_clientdata(client);
463 
464 	return sprintf(buf, "%d.0\n", data->fw_version);
465 }
466 
467 static ssize_t elan_sysfs_read_sm_ver(struct device *dev,
468 				      struct device_attribute *attr,
469 				      char *buf)
470 {
471 	struct i2c_client *client = to_i2c_client(dev);
472 	struct elan_tp_data *data = i2c_get_clientdata(client);
473 
474 	return sprintf(buf, "%d.0\n", data->sm_version);
475 }
476 
477 static ssize_t elan_sysfs_read_iap_ver(struct device *dev,
478 				       struct device_attribute *attr,
479 				       char *buf)
480 {
481 	struct i2c_client *client = to_i2c_client(dev);
482 	struct elan_tp_data *data = i2c_get_clientdata(client);
483 
484 	return sprintf(buf, "%d.0\n", data->iap_version);
485 }
486 
487 static ssize_t elan_sysfs_update_fw(struct device *dev,
488 				    struct device_attribute *attr,
489 				    const char *buf, size_t count)
490 {
491 	struct elan_tp_data *data = dev_get_drvdata(dev);
492 	const struct firmware *fw;
493 	char *fw_name;
494 	int error;
495 	const u8 *fw_signature;
496 	static const u8 signature[] = {0xAA, 0x55, 0xCC, 0x33, 0xFF, 0xFF};
497 
498 	if (data->fw_validpage_count == 0)
499 		return -EINVAL;
500 
501 	/* Look for a firmware with the product id appended. */
502 	fw_name = kasprintf(GFP_KERNEL, ETP_FW_NAME, data->product_id);
503 	if (!fw_name) {
504 		dev_err(dev, "failed to allocate memory for firmware name\n");
505 		return -ENOMEM;
506 	}
507 
508 	dev_info(dev, "requesting fw '%s'\n", fw_name);
509 	error = request_firmware(&fw, fw_name, dev);
510 	kfree(fw_name);
511 	if (error) {
512 		dev_err(dev, "failed to request firmware: %d\n", error);
513 		return error;
514 	}
515 
516 	/* Firmware file must match signature data */
517 	fw_signature = &fw->data[data->fw_signature_address];
518 	if (memcmp(fw_signature, signature, sizeof(signature)) != 0) {
519 		dev_err(dev, "signature mismatch (expected %*ph, got %*ph)\n",
520 			(int)sizeof(signature), signature,
521 			(int)sizeof(signature), fw_signature);
522 		error = -EBADF;
523 		goto out_release_fw;
524 	}
525 
526 	error = mutex_lock_interruptible(&data->sysfs_mutex);
527 	if (error)
528 		goto out_release_fw;
529 
530 	error = elan_update_firmware(data, fw);
531 
532 	mutex_unlock(&data->sysfs_mutex);
533 
534 out_release_fw:
535 	release_firmware(fw);
536 	return error ?: count;
537 }
538 
539 static ssize_t calibrate_store(struct device *dev,
540 			       struct device_attribute *attr,
541 			       const char *buf, size_t count)
542 {
543 	struct i2c_client *client = to_i2c_client(dev);
544 	struct elan_tp_data *data = i2c_get_clientdata(client);
545 	int tries = 20;
546 	int retval;
547 	int error;
548 	u8 val[3];
549 
550 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
551 	if (retval)
552 		return retval;
553 
554 	disable_irq(client->irq);
555 
556 	data->mode |= ETP_ENABLE_CALIBRATE;
557 	retval = data->ops->set_mode(client, data->mode);
558 	if (retval) {
559 		dev_err(dev, "failed to enable calibration mode: %d\n",
560 			retval);
561 		goto out;
562 	}
563 
564 	retval = data->ops->calibrate(client);
565 	if (retval) {
566 		dev_err(dev, "failed to start calibration: %d\n",
567 			retval);
568 		goto out_disable_calibrate;
569 	}
570 
571 	val[0] = 0xff;
572 	do {
573 		/* Wait 250ms before checking if calibration has completed. */
574 		msleep(250);
575 
576 		retval = data->ops->calibrate_result(client, val);
577 		if (retval)
578 			dev_err(dev, "failed to check calibration result: %d\n",
579 				retval);
580 		else if (val[0] == 0)
581 			break; /* calibration done */
582 
583 	} while (--tries);
584 
585 	if (tries == 0) {
586 		dev_err(dev, "failed to calibrate. Timeout.\n");
587 		retval = -ETIMEDOUT;
588 	}
589 
590 out_disable_calibrate:
591 	data->mode &= ~ETP_ENABLE_CALIBRATE;
592 	error = data->ops->set_mode(data->client, data->mode);
593 	if (error) {
594 		dev_err(dev, "failed to disable calibration mode: %d\n",
595 			error);
596 		if (!retval)
597 			retval = error;
598 	}
599 out:
600 	enable_irq(client->irq);
601 	mutex_unlock(&data->sysfs_mutex);
602 	return retval ?: count;
603 }
604 
605 static ssize_t elan_sysfs_read_mode(struct device *dev,
606 				    struct device_attribute *attr,
607 				    char *buf)
608 {
609 	struct i2c_client *client = to_i2c_client(dev);
610 	struct elan_tp_data *data = i2c_get_clientdata(client);
611 	int error;
612 	enum tp_mode mode;
613 
614 	error = mutex_lock_interruptible(&data->sysfs_mutex);
615 	if (error)
616 		return error;
617 
618 	error = data->ops->iap_get_mode(data->client, &mode);
619 
620 	mutex_unlock(&data->sysfs_mutex);
621 
622 	if (error)
623 		return error;
624 
625 	return sprintf(buf, "%d\n", (int)mode);
626 }
627 
628 static DEVICE_ATTR(product_id, S_IRUGO, elan_sysfs_read_product_id, NULL);
629 static DEVICE_ATTR(firmware_version, S_IRUGO, elan_sysfs_read_fw_ver, NULL);
630 static DEVICE_ATTR(sample_version, S_IRUGO, elan_sysfs_read_sm_ver, NULL);
631 static DEVICE_ATTR(iap_version, S_IRUGO, elan_sysfs_read_iap_ver, NULL);
632 static DEVICE_ATTR(fw_checksum, S_IRUGO, elan_sysfs_read_fw_checksum, NULL);
633 static DEVICE_ATTR(mode, S_IRUGO, elan_sysfs_read_mode, NULL);
634 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, elan_sysfs_update_fw);
635 
636 static DEVICE_ATTR_WO(calibrate);
637 
638 static struct attribute *elan_sysfs_entries[] = {
639 	&dev_attr_product_id.attr,
640 	&dev_attr_firmware_version.attr,
641 	&dev_attr_sample_version.attr,
642 	&dev_attr_iap_version.attr,
643 	&dev_attr_fw_checksum.attr,
644 	&dev_attr_calibrate.attr,
645 	&dev_attr_mode.attr,
646 	&dev_attr_update_fw.attr,
647 	NULL,
648 };
649 
650 static const struct attribute_group elan_sysfs_group = {
651 	.attrs = elan_sysfs_entries,
652 };
653 
654 static ssize_t acquire_store(struct device *dev, struct device_attribute *attr,
655 			     const char *buf, size_t count)
656 {
657 	struct i2c_client *client = to_i2c_client(dev);
658 	struct elan_tp_data *data = i2c_get_clientdata(client);
659 	int error;
660 	int retval;
661 
662 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
663 	if (retval)
664 		return retval;
665 
666 	disable_irq(client->irq);
667 
668 	data->baseline_ready = false;
669 
670 	data->mode |= ETP_ENABLE_CALIBRATE;
671 	retval = data->ops->set_mode(data->client, data->mode);
672 	if (retval) {
673 		dev_err(dev, "Failed to enable calibration mode to get baseline: %d\n",
674 			retval);
675 		goto out;
676 	}
677 
678 	msleep(250);
679 
680 	retval = data->ops->get_baseline_data(data->client, true,
681 					      &data->max_baseline);
682 	if (retval) {
683 		dev_err(dev, "Failed to read max baseline form device: %d\n",
684 			retval);
685 		goto out_disable_calibrate;
686 	}
687 
688 	retval = data->ops->get_baseline_data(data->client, false,
689 					      &data->min_baseline);
690 	if (retval) {
691 		dev_err(dev, "Failed to read min baseline form device: %d\n",
692 			retval);
693 		goto out_disable_calibrate;
694 	}
695 
696 	data->baseline_ready = true;
697 
698 out_disable_calibrate:
699 	data->mode &= ~ETP_ENABLE_CALIBRATE;
700 	error = data->ops->set_mode(data->client, data->mode);
701 	if (error) {
702 		dev_err(dev, "Failed to disable calibration mode after acquiring baseline: %d\n",
703 			error);
704 		if (!retval)
705 			retval = error;
706 	}
707 out:
708 	enable_irq(client->irq);
709 	mutex_unlock(&data->sysfs_mutex);
710 	return retval ?: count;
711 }
712 
713 static ssize_t min_show(struct device *dev,
714 			struct device_attribute *attr, char *buf)
715 {
716 	struct i2c_client *client = to_i2c_client(dev);
717 	struct elan_tp_data *data = i2c_get_clientdata(client);
718 	int retval;
719 
720 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
721 	if (retval)
722 		return retval;
723 
724 	if (!data->baseline_ready) {
725 		retval = -ENODATA;
726 		goto out;
727 	}
728 
729 	retval = snprintf(buf, PAGE_SIZE, "%d", data->min_baseline);
730 
731 out:
732 	mutex_unlock(&data->sysfs_mutex);
733 	return retval;
734 }
735 
736 static ssize_t max_show(struct device *dev,
737 			struct device_attribute *attr, char *buf)
738 {
739 	struct i2c_client *client = to_i2c_client(dev);
740 	struct elan_tp_data *data = i2c_get_clientdata(client);
741 	int retval;
742 
743 	retval = mutex_lock_interruptible(&data->sysfs_mutex);
744 	if (retval)
745 		return retval;
746 
747 	if (!data->baseline_ready) {
748 		retval = -ENODATA;
749 		goto out;
750 	}
751 
752 	retval = snprintf(buf, PAGE_SIZE, "%d", data->max_baseline);
753 
754 out:
755 	mutex_unlock(&data->sysfs_mutex);
756 	return retval;
757 }
758 
759 
760 static DEVICE_ATTR_WO(acquire);
761 static DEVICE_ATTR_RO(min);
762 static DEVICE_ATTR_RO(max);
763 
764 static struct attribute *elan_baseline_sysfs_entries[] = {
765 	&dev_attr_acquire.attr,
766 	&dev_attr_min.attr,
767 	&dev_attr_max.attr,
768 	NULL,
769 };
770 
771 static const struct attribute_group elan_baseline_sysfs_group = {
772 	.name = "baseline",
773 	.attrs = elan_baseline_sysfs_entries,
774 };
775 
776 static const struct attribute_group *elan_sysfs_groups[] = {
777 	&elan_sysfs_group,
778 	&elan_baseline_sysfs_group,
779 	NULL
780 };
781 
782 /*
783  ******************************************************************
784  * Elan isr functions
785  ******************************************************************
786  */
787 static void elan_report_contact(struct elan_tp_data *data,
788 				int contact_num, bool contact_valid,
789 				u8 *finger_data)
790 {
791 	struct input_dev *input = data->input;
792 	unsigned int pos_x, pos_y;
793 	unsigned int pressure, mk_x, mk_y;
794 	unsigned int area_x, area_y, major, minor;
795 	unsigned int scaled_pressure;
796 
797 	if (contact_valid) {
798 		pos_x = ((finger_data[0] & 0xf0) << 4) |
799 						finger_data[1];
800 		pos_y = ((finger_data[0] & 0x0f) << 8) |
801 						finger_data[2];
802 		mk_x = (finger_data[3] & 0x0f);
803 		mk_y = (finger_data[3] >> 4);
804 		pressure = finger_data[4];
805 
806 		if (pos_x > data->max_x || pos_y > data->max_y) {
807 			dev_dbg(input->dev.parent,
808 				"[%d] x=%d y=%d over max (%d, %d)",
809 				contact_num, pos_x, pos_y,
810 				data->max_x, data->max_y);
811 			return;
812 		}
813 
814 		/*
815 		 * To avoid treating large finger as palm, let's reduce the
816 		 * width x and y per trace.
817 		 */
818 		area_x = mk_x * (data->width_x - ETP_FWIDTH_REDUCE);
819 		area_y = mk_y * (data->width_y - ETP_FWIDTH_REDUCE);
820 
821 		major = max(area_x, area_y);
822 		minor = min(area_x, area_y);
823 
824 		scaled_pressure = pressure + data->pressure_adjustment;
825 
826 		if (scaled_pressure > ETP_MAX_PRESSURE)
827 			scaled_pressure = ETP_MAX_PRESSURE;
828 
829 		input_mt_slot(input, contact_num);
830 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
831 		input_report_abs(input, ABS_MT_POSITION_X, pos_x);
832 		input_report_abs(input, ABS_MT_POSITION_Y, data->max_y - pos_y);
833 		input_report_abs(input, ABS_MT_PRESSURE, scaled_pressure);
834 		input_report_abs(input, ABS_TOOL_WIDTH, mk_x);
835 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
836 		input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
837 	} else {
838 		input_mt_slot(input, contact_num);
839 		input_mt_report_slot_state(input, MT_TOOL_FINGER, false);
840 	}
841 }
842 
843 static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
844 {
845 	struct input_dev *input = data->input;
846 	u8 *finger_data = &packet[ETP_FINGER_DATA_OFFSET];
847 	int i;
848 	u8 tp_info = packet[ETP_TOUCH_INFO_OFFSET];
849 	u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
850 	bool contact_valid, hover_event;
851 
852 	hover_event = hover_info & 0x40;
853 	for (i = 0; i < ETP_MAX_FINGERS; i++) {
854 		contact_valid = tp_info & (1U << (3 + i));
855 		elan_report_contact(data, i, contact_valid, finger_data);
856 
857 		if (contact_valid)
858 			finger_data += ETP_FINGER_DATA_LEN;
859 	}
860 
861 	input_report_key(input, BTN_LEFT, tp_info & 0x01);
862 	input_report_abs(input, ABS_DISTANCE, hover_event != 0);
863 	input_mt_report_pointer_emulation(input, true);
864 	input_sync(input);
865 }
866 
867 static irqreturn_t elan_isr(int irq, void *dev_id)
868 {
869 	struct elan_tp_data *data = dev_id;
870 	struct device *dev = &data->client->dev;
871 	int error;
872 	u8 report[ETP_MAX_REPORT_LEN];
873 
874 	/*
875 	 * When device is connected to i2c bus, when all IAP page writes
876 	 * complete, the driver will receive interrupt and must read
877 	 * 0000 to confirm that IAP is finished.
878 	*/
879 	if (data->in_fw_update) {
880 		complete(&data->fw_completion);
881 		goto out;
882 	}
883 
884 	error = data->ops->get_report(data->client, report);
885 	if (error)
886 		goto out;
887 
888 	if (report[ETP_REPORT_ID_OFFSET] != ETP_REPORT_ID)
889 		dev_err(dev, "invalid report id data (%x)\n",
890 			report[ETP_REPORT_ID_OFFSET]);
891 	else
892 		elan_report_absolute(data, report);
893 
894 out:
895 	return IRQ_HANDLED;
896 }
897 
898 /*
899  ******************************************************************
900  * Elan initialization functions
901  ******************************************************************
902  */
903 static int elan_setup_input_device(struct elan_tp_data *data)
904 {
905 	struct device *dev = &data->client->dev;
906 	struct input_dev *input;
907 	unsigned int max_width = max(data->width_x, data->width_y);
908 	unsigned int min_width = min(data->width_x, data->width_y);
909 	int error;
910 
911 	input = devm_input_allocate_device(dev);
912 	if (!input)
913 		return -ENOMEM;
914 
915 	input->name = "Elan Touchpad";
916 	input->id.bustype = BUS_I2C;
917 	input_set_drvdata(input, data);
918 
919 	error = input_mt_init_slots(input, ETP_MAX_FINGERS,
920 				    INPUT_MT_POINTER | INPUT_MT_DROP_UNUSED);
921 	if (error) {
922 		dev_err(dev, "failed to initialize MT slots: %d\n", error);
923 		return error;
924 	}
925 
926 	__set_bit(EV_ABS, input->evbit);
927 	__set_bit(INPUT_PROP_POINTER, input->propbit);
928 	__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
929 	__set_bit(BTN_LEFT, input->keybit);
930 
931 	/* Set up ST parameters */
932 	input_set_abs_params(input, ABS_X, 0, data->max_x, 0, 0);
933 	input_set_abs_params(input, ABS_Y, 0, data->max_y, 0, 0);
934 	input_abs_set_res(input, ABS_X, data->x_res);
935 	input_abs_set_res(input, ABS_Y, data->y_res);
936 	input_set_abs_params(input, ABS_PRESSURE, 0, ETP_MAX_PRESSURE, 0, 0);
937 	input_set_abs_params(input, ABS_TOOL_WIDTH, 0, ETP_FINGER_WIDTH, 0, 0);
938 	input_set_abs_params(input, ABS_DISTANCE, 0, 1, 0, 0);
939 
940 	/* And MT parameters */
941 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, data->max_x, 0, 0);
942 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, data->max_y, 0, 0);
943 	input_abs_set_res(input, ABS_MT_POSITION_X, data->x_res);
944 	input_abs_set_res(input, ABS_MT_POSITION_Y, data->y_res);
945 	input_set_abs_params(input, ABS_MT_PRESSURE, 0,
946 			     ETP_MAX_PRESSURE, 0, 0);
947 	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0,
948 			     ETP_FINGER_WIDTH * max_width, 0, 0);
949 	input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0,
950 			     ETP_FINGER_WIDTH * min_width, 0, 0);
951 
952 	data->input = input;
953 
954 	return 0;
955 }
956 
957 static void elan_disable_regulator(void *_data)
958 {
959 	struct elan_tp_data *data = _data;
960 
961 	regulator_disable(data->vcc);
962 }
963 
964 static void elan_remove_sysfs_groups(void *_data)
965 {
966 	struct elan_tp_data *data = _data;
967 
968 	sysfs_remove_groups(&data->client->dev.kobj, elan_sysfs_groups);
969 }
970 
971 static int elan_probe(struct i2c_client *client,
972 		      const struct i2c_device_id *dev_id)
973 {
974 	const struct elan_transport_ops *transport_ops;
975 	struct device *dev = &client->dev;
976 	struct elan_tp_data *data;
977 	unsigned long irqflags;
978 	int error;
979 
980 	if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_I2C) &&
981 	    i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
982 		transport_ops = &elan_i2c_ops;
983 	} else if (IS_ENABLED(CONFIG_MOUSE_ELAN_I2C_SMBUS) &&
984 		   i2c_check_functionality(client->adapter,
985 					   I2C_FUNC_SMBUS_BYTE_DATA |
986 						I2C_FUNC_SMBUS_BLOCK_DATA |
987 						I2C_FUNC_SMBUS_I2C_BLOCK)) {
988 		transport_ops = &elan_smbus_ops;
989 	} else {
990 		dev_err(dev, "not a supported I2C/SMBus adapter\n");
991 		return -EIO;
992 	}
993 
994 	data = devm_kzalloc(&client->dev, sizeof(struct elan_tp_data),
995 			    GFP_KERNEL);
996 	if (!data)
997 		return -ENOMEM;
998 
999 	i2c_set_clientdata(client, data);
1000 
1001 	data->ops = transport_ops;
1002 	data->client = client;
1003 	init_completion(&data->fw_completion);
1004 	mutex_init(&data->sysfs_mutex);
1005 
1006 	data->vcc = devm_regulator_get(&client->dev, "vcc");
1007 	if (IS_ERR(data->vcc)) {
1008 		error = PTR_ERR(data->vcc);
1009 		if (error != -EPROBE_DEFER)
1010 			dev_err(&client->dev,
1011 				"Failed to get 'vcc' regulator: %d\n",
1012 				error);
1013 		return error;
1014 	}
1015 
1016 	error = regulator_enable(data->vcc);
1017 	if (error) {
1018 		dev_err(&client->dev,
1019 			"Failed to enable regulator: %d\n", error);
1020 		return error;
1021 	}
1022 
1023 	error = devm_add_action(&client->dev,
1024 				elan_disable_regulator, data);
1025 	if (error) {
1026 		regulator_disable(data->vcc);
1027 		dev_err(&client->dev,
1028 			"Failed to add disable regulator action: %d\n",
1029 			error);
1030 		return error;
1031 	}
1032 
1033 	/* Initialize the touchpad. */
1034 	error = elan_initialize(data);
1035 	if (error)
1036 		return error;
1037 
1038 	error = elan_query_device_info(data);
1039 	if (error)
1040 		return error;
1041 
1042 	error = elan_query_device_parameters(data);
1043 	if (error)
1044 		return error;
1045 
1046 	dev_dbg(&client->dev,
1047 		"Elan Touchpad Information:\n"
1048 		"    Module product ID:  0x%04x\n"
1049 		"    Firmware Version:  0x%04x\n"
1050 		"    Sample Version:  0x%04x\n"
1051 		"    IAP Version:  0x%04x\n"
1052 		"    Max ABS X,Y:   %d,%d\n"
1053 		"    Width X,Y:   %d,%d\n"
1054 		"    Resolution X,Y:   %d,%d (dots/mm)\n",
1055 		data->product_id,
1056 		data->fw_version,
1057 		data->sm_version,
1058 		data->iap_version,
1059 		data->max_x, data->max_y,
1060 		data->width_x, data->width_y,
1061 		data->x_res, data->y_res);
1062 
1063 	/* Set up input device properties based on queried parameters. */
1064 	error = elan_setup_input_device(data);
1065 	if (error)
1066 		return error;
1067 
1068 	/*
1069 	 * Systems using device tree should set up interrupt via DTS,
1070 	 * the rest will use the default falling edge interrupts.
1071 	 */
1072 	irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
1073 
1074 	error = devm_request_threaded_irq(&client->dev, client->irq,
1075 					  NULL, elan_isr,
1076 					  irqflags | IRQF_ONESHOT,
1077 					  client->name, data);
1078 	if (error) {
1079 		dev_err(&client->dev, "cannot register irq=%d\n", client->irq);
1080 		return error;
1081 	}
1082 
1083 	error = sysfs_create_groups(&client->dev.kobj, elan_sysfs_groups);
1084 	if (error) {
1085 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1086 			error);
1087 		return error;
1088 	}
1089 
1090 	error = devm_add_action(&client->dev,
1091 				elan_remove_sysfs_groups, data);
1092 	if (error) {
1093 		elan_remove_sysfs_groups(data);
1094 		dev_err(&client->dev,
1095 			"Failed to add sysfs cleanup action: %d\n",
1096 			error);
1097 		return error;
1098 	}
1099 
1100 	error = input_register_device(data->input);
1101 	if (error) {
1102 		dev_err(&client->dev, "failed to register input device: %d\n",
1103 			error);
1104 		return error;
1105 	}
1106 
1107 	/*
1108 	 * Systems using device tree should set up wakeup via DTS,
1109 	 * the rest will configure device as wakeup source by default.
1110 	 */
1111 	if (!client->dev.of_node)
1112 		device_init_wakeup(&client->dev, true);
1113 
1114 	return 0;
1115 }
1116 
1117 static int __maybe_unused elan_suspend(struct device *dev)
1118 {
1119 	struct i2c_client *client = to_i2c_client(dev);
1120 	struct elan_tp_data *data = i2c_get_clientdata(client);
1121 	int ret;
1122 
1123 	/*
1124 	 * We are taking the mutex to make sure sysfs operations are
1125 	 * complete before we attempt to bring the device into low[er]
1126 	 * power mode.
1127 	 */
1128 	ret = mutex_lock_interruptible(&data->sysfs_mutex);
1129 	if (ret)
1130 		return ret;
1131 
1132 	disable_irq(client->irq);
1133 
1134 	if (device_may_wakeup(dev)) {
1135 		ret = elan_sleep(data);
1136 		/* Enable wake from IRQ */
1137 		data->irq_wake = (enable_irq_wake(client->irq) == 0);
1138 	} else {
1139 		ret = elan_disable_power(data);
1140 	}
1141 
1142 	mutex_unlock(&data->sysfs_mutex);
1143 	return ret;
1144 }
1145 
1146 static int __maybe_unused elan_resume(struct device *dev)
1147 {
1148 	struct i2c_client *client = to_i2c_client(dev);
1149 	struct elan_tp_data *data = i2c_get_clientdata(client);
1150 	int error;
1151 
1152 	if (device_may_wakeup(dev) && data->irq_wake) {
1153 		disable_irq_wake(client->irq);
1154 		data->irq_wake = false;
1155 	}
1156 
1157 	error = elan_enable_power(data);
1158 	if (error) {
1159 		dev_err(dev, "power up when resuming failed: %d\n", error);
1160 		goto err;
1161 	}
1162 
1163 	error = elan_initialize(data);
1164 	if (error)
1165 		dev_err(dev, "initialize when resuming failed: %d\n", error);
1166 
1167 err:
1168 	enable_irq(data->client->irq);
1169 	return error;
1170 }
1171 
1172 static SIMPLE_DEV_PM_OPS(elan_pm_ops, elan_suspend, elan_resume);
1173 
1174 static const struct i2c_device_id elan_id[] = {
1175 	{ DRIVER_NAME, 0 },
1176 	{ },
1177 };
1178 MODULE_DEVICE_TABLE(i2c, elan_id);
1179 
1180 #ifdef CONFIG_ACPI
1181 static const struct acpi_device_id elan_acpi_id[] = {
1182 	{ "ELAN0000", 0 },
1183 	{ "ELAN0100", 0 },
1184 	{ "ELAN0600", 0 },
1185 	{ "ELAN1000", 0 },
1186 	{ }
1187 };
1188 MODULE_DEVICE_TABLE(acpi, elan_acpi_id);
1189 #endif
1190 
1191 #ifdef CONFIG_OF
1192 static const struct of_device_id elan_of_match[] = {
1193 	{ .compatible = "elan,ekth3000" },
1194 	{ /* sentinel */ }
1195 };
1196 MODULE_DEVICE_TABLE(of, elan_of_match);
1197 #endif
1198 
1199 static struct i2c_driver elan_driver = {
1200 	.driver = {
1201 		.name	= DRIVER_NAME,
1202 		.pm	= &elan_pm_ops,
1203 		.acpi_match_table = ACPI_PTR(elan_acpi_id),
1204 		.of_match_table = of_match_ptr(elan_of_match),
1205 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1206 	},
1207 	.probe		= elan_probe,
1208 	.id_table	= elan_id,
1209 };
1210 
1211 module_i2c_driver(elan_driver);
1212 
1213 MODULE_AUTHOR("Duson Lin <dusonlin@emc.com.tw>");
1214 MODULE_DESCRIPTION("Elan I2C/SMBus Touchpad driver");
1215 MODULE_LICENSE("GPL");
1216 MODULE_VERSION(ELAN_DRIVER_VERSION);
1217