1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Elan Microelectronics touch panels with I2C interface
4  *
5  * Copyright (C) 2014 Elan Microelectronics Corporation.
6  * Scott Liu <scott.liu@emc.com.tw>
7  *
8  * This code is partly based on hid-multitouch.c:
9  *
10  *  Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
11  *  Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
12  *  Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
13  *
14  * This code is partly based on i2c-hid.c:
15  *
16  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
17  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
18  * Copyright (c) 2012 Red Hat, Inc
19  */
20 
21 
22 #include <linux/bits.h>
23 #include <linux/module.h>
24 #include <linux/input.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/platform_device.h>
28 #include <linux/async.h>
29 #include <linux/i2c.h>
30 #include <linux/delay.h>
31 #include <linux/uaccess.h>
32 #include <linux/buffer_head.h>
33 #include <linux/slab.h>
34 #include <linux/firmware.h>
35 #include <linux/input/mt.h>
36 #include <linux/acpi.h>
37 #include <linux/of.h>
38 #include <linux/gpio/consumer.h>
39 #include <linux/regulator/consumer.h>
40 #include <asm/unaligned.h>
41 
42 /* Device, Driver information */
43 #define DEVICE_NAME	"elants_i2c"
44 
45 /* Convert from rows or columns into resolution */
46 #define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
47 
48 /* FW header data */
49 #define HEADER_SIZE		4
50 #define FW_HDR_TYPE		0
51 #define FW_HDR_COUNT		1
52 #define FW_HDR_LENGTH		2
53 
54 /* Buffer mode Queue Header information */
55 #define QUEUE_HEADER_SINGLE	0x62
56 #define QUEUE_HEADER_NORMAL	0X63
57 #define QUEUE_HEADER_WAIT	0x64
58 
59 /* Command header definition */
60 #define CMD_HEADER_WRITE	0x54
61 #define CMD_HEADER_READ		0x53
62 #define CMD_HEADER_6B_READ	0x5B
63 #define CMD_HEADER_ROM_READ	0x96
64 #define CMD_HEADER_RESP		0x52
65 #define CMD_HEADER_6B_RESP	0x9B
66 #define CMD_HEADER_ROM_RESP	0x95
67 #define CMD_HEADER_HELLO	0x55
68 #define CMD_HEADER_REK		0x66
69 
70 /* FW position data */
71 #define PACKET_SIZE		55
72 #define MAX_CONTACT_NUM		10
73 #define FW_POS_HEADER		0
74 #define FW_POS_STATE		1
75 #define FW_POS_TOTAL		2
76 #define FW_POS_XY		3
77 #define FW_POS_TOOL_TYPE	33
78 #define FW_POS_CHECKSUM		34
79 #define FW_POS_WIDTH		35
80 #define FW_POS_PRESSURE		45
81 
82 #define HEADER_REPORT_10_FINGER	0x62
83 
84 /* Header (4 bytes) plus 3 fill 10-finger packets */
85 #define MAX_PACKET_SIZE		169
86 
87 #define BOOT_TIME_DELAY_MS	50
88 
89 /* FW read command, 0x53 0x?? 0x0, 0x01 */
90 #define E_ELAN_INFO_FW_VER	0x00
91 #define E_ELAN_INFO_BC_VER	0x10
92 #define E_ELAN_INFO_TEST_VER	0xE0
93 #define E_ELAN_INFO_FW_ID	0xF0
94 #define E_INFO_OSR		0xD6
95 #define E_INFO_PHY_SCAN		0xD7
96 #define E_INFO_PHY_DRIVER	0xD8
97 
98 #define MAX_RETRIES		3
99 #define MAX_FW_UPDATE_RETRIES	30
100 
101 #define ELAN_FW_PAGESIZE	132
102 
103 /* calibration timeout definition */
104 #define ELAN_CALI_TIMEOUT_MSEC	12000
105 
106 #define ELAN_POWERON_DELAY_USEC	500
107 #define ELAN_RESET_DELAY_MSEC	20
108 
109 enum elants_state {
110 	ELAN_STATE_NORMAL,
111 	ELAN_WAIT_QUEUE_HEADER,
112 	ELAN_WAIT_RECALIBRATION,
113 };
114 
115 enum elants_iap_mode {
116 	ELAN_IAP_OPERATIONAL,
117 	ELAN_IAP_RECOVERY,
118 };
119 
120 /* struct elants_data - represents state of Elan touchscreen device */
121 struct elants_data {
122 	struct i2c_client *client;
123 	struct input_dev *input;
124 
125 	struct regulator *vcc33;
126 	struct regulator *vccio;
127 	struct gpio_desc *reset_gpio;
128 
129 	u16 fw_version;
130 	u8 test_version;
131 	u8 solution_version;
132 	u8 bc_version;
133 	u8 iap_version;
134 	u16 hw_version;
135 	unsigned int x_res;	/* resolution in units/mm */
136 	unsigned int y_res;
137 	unsigned int x_max;
138 	unsigned int y_max;
139 
140 	enum elants_state state;
141 	enum elants_iap_mode iap_mode;
142 
143 	/* Guards against concurrent access to the device via sysfs */
144 	struct mutex sysfs_mutex;
145 
146 	u8 cmd_resp[HEADER_SIZE];
147 	struct completion cmd_done;
148 
149 	bool wake_irq_enabled;
150 	bool keep_power_in_suspend;
151 
152 	/* Must be last to be used for DMA operations */
153 	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
154 };
155 
156 static int elants_i2c_send(struct i2c_client *client,
157 			   const void *data, size_t size)
158 {
159 	int ret;
160 
161 	ret = i2c_master_send(client, data, size);
162 	if (ret == size)
163 		return 0;
164 
165 	if (ret >= 0)
166 		ret = -EIO;
167 
168 	dev_err(&client->dev, "%s failed (%*ph): %d\n",
169 		__func__, (int)size, data, ret);
170 
171 	return ret;
172 }
173 
174 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
175 {
176 	int ret;
177 
178 	ret = i2c_master_recv(client, data, size);
179 	if (ret == size)
180 		return 0;
181 
182 	if (ret >= 0)
183 		ret = -EIO;
184 
185 	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
186 
187 	return ret;
188 }
189 
190 static int elants_i2c_execute_command(struct i2c_client *client,
191 				      const u8 *cmd, size_t cmd_size,
192 				      u8 *resp, size_t resp_size)
193 {
194 	struct i2c_msg msgs[2];
195 	int ret;
196 	u8 expected_response;
197 
198 	switch (cmd[0]) {
199 	case CMD_HEADER_READ:
200 		expected_response = CMD_HEADER_RESP;
201 		break;
202 
203 	case CMD_HEADER_6B_READ:
204 		expected_response = CMD_HEADER_6B_RESP;
205 		break;
206 
207 	case CMD_HEADER_ROM_READ:
208 		expected_response = CMD_HEADER_ROM_RESP;
209 		break;
210 
211 	default:
212 		dev_err(&client->dev, "%s: invalid command %*ph\n",
213 			__func__, (int)cmd_size, cmd);
214 		return -EINVAL;
215 	}
216 
217 	msgs[0].addr = client->addr;
218 	msgs[0].flags = client->flags & I2C_M_TEN;
219 	msgs[0].len = cmd_size;
220 	msgs[0].buf = (u8 *)cmd;
221 
222 	msgs[1].addr = client->addr;
223 	msgs[1].flags = client->flags & I2C_M_TEN;
224 	msgs[1].flags |= I2C_M_RD;
225 	msgs[1].len = resp_size;
226 	msgs[1].buf = resp;
227 
228 	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
229 	if (ret < 0)
230 		return ret;
231 
232 	if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
233 		return -EIO;
234 
235 	return 0;
236 }
237 
238 static int elants_i2c_calibrate(struct elants_data *ts)
239 {
240 	struct i2c_client *client = ts->client;
241 	int ret, error;
242 	static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
243 	static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
244 	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
245 
246 	disable_irq(client->irq);
247 
248 	ts->state = ELAN_WAIT_RECALIBRATION;
249 	reinit_completion(&ts->cmd_done);
250 
251 	elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
252 	elants_i2c_send(client, rek, sizeof(rek));
253 
254 	enable_irq(client->irq);
255 
256 	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
257 				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
258 
259 	ts->state = ELAN_STATE_NORMAL;
260 
261 	if (ret <= 0) {
262 		error = ret < 0 ? ret : -ETIMEDOUT;
263 		dev_err(&client->dev,
264 			"error while waiting for calibration to complete: %d\n",
265 			error);
266 		return error;
267 	}
268 
269 	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
270 		dev_err(&client->dev,
271 			"unexpected calibration response: %*ph\n",
272 			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
273 		return -EINVAL;
274 	}
275 
276 	return 0;
277 }
278 
279 static int elants_i2c_sw_reset(struct i2c_client *client)
280 {
281 	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
282 	int error;
283 
284 	error = elants_i2c_send(client, soft_rst_cmd,
285 				sizeof(soft_rst_cmd));
286 	if (error) {
287 		dev_err(&client->dev, "software reset failed: %d\n", error);
288 		return error;
289 	}
290 
291 	/*
292 	 * We should wait at least 10 msec (but no more than 40) before
293 	 * sending fastboot or IAP command to the device.
294 	 */
295 	msleep(30);
296 
297 	return 0;
298 }
299 
300 static u16 elants_i2c_parse_version(u8 *buf)
301 {
302 	return get_unaligned_be32(buf) >> 4;
303 }
304 
305 static int elants_i2c_query_hw_version(struct elants_data *ts)
306 {
307 	struct i2c_client *client = ts->client;
308 	int error, retry_cnt;
309 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
310 	u8 resp[HEADER_SIZE];
311 
312 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
313 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
314 						   resp, sizeof(resp));
315 		if (!error) {
316 			ts->hw_version = elants_i2c_parse_version(resp);
317 			if (ts->hw_version != 0xffff)
318 				return 0;
319 		}
320 
321 		dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
322 			error, (int)sizeof(resp), resp);
323 	}
324 
325 	if (error) {
326 		dev_err(&client->dev,
327 			"Failed to read fw id: %d\n", error);
328 		return error;
329 	}
330 
331 	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
332 
333 	return -EINVAL;
334 }
335 
336 static int elants_i2c_query_fw_version(struct elants_data *ts)
337 {
338 	struct i2c_client *client = ts->client;
339 	int error, retry_cnt;
340 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
341 	u8 resp[HEADER_SIZE];
342 
343 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
344 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
345 						   resp, sizeof(resp));
346 		if (!error) {
347 			ts->fw_version = elants_i2c_parse_version(resp);
348 			if (ts->fw_version != 0x0000 &&
349 			    ts->fw_version != 0xffff)
350 				return 0;
351 		}
352 
353 		dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
354 			error, (int)sizeof(resp), resp);
355 	}
356 
357 	dev_err(&client->dev,
358 		"Failed to read fw version or fw version is invalid\n");
359 
360 	return -EINVAL;
361 }
362 
363 static int elants_i2c_query_test_version(struct elants_data *ts)
364 {
365 	struct i2c_client *client = ts->client;
366 	int error, retry_cnt;
367 	u16 version;
368 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
369 	u8 resp[HEADER_SIZE];
370 
371 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
372 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
373 						   resp, sizeof(resp));
374 		if (!error) {
375 			version = elants_i2c_parse_version(resp);
376 			ts->test_version = version >> 8;
377 			ts->solution_version = version & 0xff;
378 
379 			return 0;
380 		}
381 
382 		dev_dbg(&client->dev,
383 			"read test version error rc=%d, buf=%*phC\n",
384 			error, (int)sizeof(resp), resp);
385 	}
386 
387 	dev_err(&client->dev, "Failed to read test version\n");
388 
389 	return -EINVAL;
390 }
391 
392 static int elants_i2c_query_bc_version(struct elants_data *ts)
393 {
394 	struct i2c_client *client = ts->client;
395 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
396 	u8 resp[HEADER_SIZE];
397 	u16 version;
398 	int error;
399 
400 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
401 					   resp, sizeof(resp));
402 	if (error) {
403 		dev_err(&client->dev,
404 			"read BC version error=%d, buf=%*phC\n",
405 			error, (int)sizeof(resp), resp);
406 		return error;
407 	}
408 
409 	version = elants_i2c_parse_version(resp);
410 	ts->bc_version = version >> 8;
411 	ts->iap_version = version & 0xff;
412 
413 	return 0;
414 }
415 
416 static int elants_i2c_query_ts_info(struct elants_data *ts)
417 {
418 	struct i2c_client *client = ts->client;
419 	int error;
420 	u8 resp[17];
421 	u16 phy_x, phy_y, rows, cols, osr;
422 	const u8 get_resolution_cmd[] = {
423 		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
424 	};
425 	const u8 get_osr_cmd[] = {
426 		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
427 	};
428 	const u8 get_physical_scan_cmd[] = {
429 		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
430 	};
431 	const u8 get_physical_drive_cmd[] = {
432 		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
433 	};
434 
435 	/* Get trace number */
436 	error = elants_i2c_execute_command(client,
437 					   get_resolution_cmd,
438 					   sizeof(get_resolution_cmd),
439 					   resp, sizeof(resp));
440 	if (error) {
441 		dev_err(&client->dev, "get resolution command failed: %d\n",
442 			error);
443 		return error;
444 	}
445 
446 	rows = resp[2] + resp[6] + resp[10];
447 	cols = resp[3] + resp[7] + resp[11];
448 
449 	/* Process mm_to_pixel information */
450 	error = elants_i2c_execute_command(client,
451 					   get_osr_cmd, sizeof(get_osr_cmd),
452 					   resp, sizeof(resp));
453 	if (error) {
454 		dev_err(&client->dev, "get osr command failed: %d\n",
455 			error);
456 		return error;
457 	}
458 
459 	osr = resp[3];
460 
461 	error = elants_i2c_execute_command(client,
462 					   get_physical_scan_cmd,
463 					   sizeof(get_physical_scan_cmd),
464 					   resp, sizeof(resp));
465 	if (error) {
466 		dev_err(&client->dev, "get physical scan command failed: %d\n",
467 			error);
468 		return error;
469 	}
470 
471 	phy_x = get_unaligned_be16(&resp[2]);
472 
473 	error = elants_i2c_execute_command(client,
474 					   get_physical_drive_cmd,
475 					   sizeof(get_physical_drive_cmd),
476 					   resp, sizeof(resp));
477 	if (error) {
478 		dev_err(&client->dev, "get physical drive command failed: %d\n",
479 			error);
480 		return error;
481 	}
482 
483 	phy_y = get_unaligned_be16(&resp[2]);
484 
485 	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
486 
487 	if (rows == 0 || cols == 0 || osr == 0) {
488 		dev_warn(&client->dev,
489 			 "invalid trace number data: %d, %d, %d\n",
490 			 rows, cols, osr);
491 	} else {
492 		/* translate trace number to TS resolution */
493 		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
494 		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
495 		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
496 		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
497 	}
498 
499 	return 0;
500 }
501 
502 static int elants_i2c_fastboot(struct i2c_client *client)
503 {
504 	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
505 	int error;
506 
507 	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
508 	if (error) {
509 		dev_err(&client->dev, "boot failed: %d\n", error);
510 		return error;
511 	}
512 
513 	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
514 	return 0;
515 }
516 
517 static int elants_i2c_initialize(struct elants_data *ts)
518 {
519 	struct i2c_client *client = ts->client;
520 	int error, error2, retry_cnt;
521 	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
522 	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
523 	u8 buf[HEADER_SIZE];
524 
525 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
526 		error = elants_i2c_sw_reset(client);
527 		if (error) {
528 			/* Continue initializing if it's the last try */
529 			if (retry_cnt < MAX_RETRIES - 1)
530 				continue;
531 		}
532 
533 		error = elants_i2c_fastboot(client);
534 		if (error) {
535 			/* Continue initializing if it's the last try */
536 			if (retry_cnt < MAX_RETRIES - 1)
537 				continue;
538 		}
539 
540 		/* Wait for Hello packet */
541 		msleep(BOOT_TIME_DELAY_MS);
542 
543 		error = elants_i2c_read(client, buf, sizeof(buf));
544 		if (error) {
545 			dev_err(&client->dev,
546 				"failed to read 'hello' packet: %d\n", error);
547 		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
548 			ts->iap_mode = ELAN_IAP_OPERATIONAL;
549 			break;
550 		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
551 			/*
552 			 * Setting error code will mark device
553 			 * in recovery mode below.
554 			 */
555 			error = -EIO;
556 			break;
557 		} else {
558 			error = -EINVAL;
559 			dev_err(&client->dev,
560 				"invalid 'hello' packet: %*ph\n",
561 				(int)sizeof(buf), buf);
562 		}
563 	}
564 
565 	/* hw version is available even if device in recovery state */
566 	error2 = elants_i2c_query_hw_version(ts);
567 	if (!error2)
568 		error2 = elants_i2c_query_bc_version(ts);
569 	if (!error)
570 		error = error2;
571 
572 	if (!error)
573 		error = elants_i2c_query_fw_version(ts);
574 	if (!error)
575 		error = elants_i2c_query_test_version(ts);
576 	if (!error)
577 		error = elants_i2c_query_ts_info(ts);
578 
579 	if (error)
580 		ts->iap_mode = ELAN_IAP_RECOVERY;
581 
582 	return 0;
583 }
584 
585 /*
586  * Firmware update interface.
587  */
588 
589 static int elants_i2c_fw_write_page(struct i2c_client *client,
590 				    const void *page)
591 {
592 	const u8 ack_ok[] = { 0xaa, 0xaa };
593 	u8 buf[2];
594 	int retry;
595 	int error;
596 
597 	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
598 		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
599 		if (error) {
600 			dev_err(&client->dev,
601 				"IAP Write Page failed: %d\n", error);
602 			continue;
603 		}
604 
605 		error = elants_i2c_read(client, buf, 2);
606 		if (error) {
607 			dev_err(&client->dev,
608 				"IAP Ack read failed: %d\n", error);
609 			return error;
610 		}
611 
612 		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
613 			return 0;
614 
615 		error = -EIO;
616 		dev_err(&client->dev,
617 			"IAP Get Ack Error [%02x:%02x]\n",
618 			buf[0], buf[1]);
619 	}
620 
621 	return error;
622 }
623 
624 static int elants_i2c_validate_remark_id(struct elants_data *ts,
625 					 const struct firmware *fw)
626 {
627 	struct i2c_client *client = ts->client;
628 	int error;
629 	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
630 	u8 resp[6] = { 0 };
631 	u16 ts_remark_id = 0;
632 	u16 fw_remark_id = 0;
633 
634 	/* Compare TS Remark ID and FW Remark ID */
635 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
636 					resp, sizeof(resp));
637 	if (error) {
638 		dev_err(&client->dev, "failed to query Remark ID: %d\n", error);
639 		return error;
640 	}
641 
642 	ts_remark_id = get_unaligned_be16(&resp[3]);
643 
644 	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
645 
646 	if (fw_remark_id != ts_remark_id) {
647 		dev_err(&client->dev,
648 			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
649 			ts_remark_id, fw_remark_id);
650 		return -EINVAL;
651 	}
652 
653 	return 0;
654 }
655 
656 static int elants_i2c_do_update_firmware(struct i2c_client *client,
657 					 const struct firmware *fw,
658 					 bool force)
659 {
660 	struct elants_data *ts = i2c_get_clientdata(client);
661 	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
662 	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
663 	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
664 	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
665 	u8 buf[HEADER_SIZE];
666 	u16 send_id;
667 	int page, n_fw_pages;
668 	int error;
669 	bool check_remark_id = ts->iap_version >= 0x60;
670 
671 	/* Recovery mode detection! */
672 	if (force) {
673 		dev_dbg(&client->dev, "Recovery mode procedure\n");
674 
675 		if (check_remark_id) {
676 			error = elants_i2c_validate_remark_id(ts, fw);
677 			if (error)
678 				return error;
679 		}
680 
681 		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
682 		if (error) {
683 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
684 				error);
685 			return error;
686 		}
687 	} else {
688 		/* Start IAP Procedure */
689 		dev_dbg(&client->dev, "Normal IAP procedure\n");
690 
691 		/* Close idle mode */
692 		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
693 		if (error)
694 			dev_err(&client->dev, "Failed close idle: %d\n", error);
695 		msleep(60);
696 
697 		elants_i2c_sw_reset(client);
698 		msleep(20);
699 
700 		if (check_remark_id) {
701 			error = elants_i2c_validate_remark_id(ts, fw);
702 			if (error)
703 				return error;
704 		}
705 
706 		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
707 		if (error) {
708 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
709 				error);
710 			return error;
711 		}
712 	}
713 
714 	msleep(20);
715 
716 	/* check IAP state */
717 	error = elants_i2c_read(client, buf, 4);
718 	if (error) {
719 		dev_err(&client->dev,
720 			"failed to read IAP acknowledgement: %d\n",
721 			error);
722 		return error;
723 	}
724 
725 	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
726 		dev_err(&client->dev,
727 			"failed to enter IAP: %*ph (expected %*ph)\n",
728 			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
729 		return -EIO;
730 	}
731 
732 	dev_info(&client->dev, "successfully entered IAP mode");
733 
734 	send_id = client->addr;
735 	error = elants_i2c_send(client, &send_id, 1);
736 	if (error) {
737 		dev_err(&client->dev, "sending dummy byte failed: %d\n",
738 			error);
739 		return error;
740 	}
741 
742 	/* Clear the last page of Master */
743 	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
744 	if (error) {
745 		dev_err(&client->dev, "clearing of the last page failed: %d\n",
746 			error);
747 		return error;
748 	}
749 
750 	error = elants_i2c_read(client, buf, 2);
751 	if (error) {
752 		dev_err(&client->dev,
753 			"failed to read ACK for clearing the last page: %d\n",
754 			error);
755 		return error;
756 	}
757 
758 	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
759 	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
760 
761 	for (page = 0; page < n_fw_pages; page++) {
762 		error = elants_i2c_fw_write_page(client,
763 					fw->data + page * ELAN_FW_PAGESIZE);
764 		if (error) {
765 			dev_err(&client->dev,
766 				"failed to write FW page %d: %d\n",
767 				page, error);
768 			return error;
769 		}
770 	}
771 
772 	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
773 	msleep(300);
774 
775 	dev_info(&client->dev, "firmware update completed\n");
776 	return 0;
777 }
778 
779 static int elants_i2c_fw_update(struct elants_data *ts)
780 {
781 	struct i2c_client *client = ts->client;
782 	const struct firmware *fw;
783 	char *fw_name;
784 	int error;
785 
786 	fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
787 	if (!fw_name)
788 		return -ENOMEM;
789 
790 	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
791 	error = request_firmware(&fw, fw_name, &client->dev);
792 	kfree(fw_name);
793 	if (error) {
794 		dev_err(&client->dev, "failed to request firmware: %d\n",
795 			error);
796 		return error;
797 	}
798 
799 	if (fw->size % ELAN_FW_PAGESIZE) {
800 		dev_err(&client->dev, "invalid firmware length: %zu\n",
801 			fw->size);
802 		error = -EINVAL;
803 		goto out;
804 	}
805 
806 	disable_irq(client->irq);
807 
808 	error = elants_i2c_do_update_firmware(client, fw,
809 					ts->iap_mode == ELAN_IAP_RECOVERY);
810 	if (error) {
811 		dev_err(&client->dev, "firmware update failed: %d\n", error);
812 		ts->iap_mode = ELAN_IAP_RECOVERY;
813 		goto out_enable_irq;
814 	}
815 
816 	error = elants_i2c_initialize(ts);
817 	if (error) {
818 		dev_err(&client->dev,
819 			"failed to initialize device after firmware update: %d\n",
820 			error);
821 		ts->iap_mode = ELAN_IAP_RECOVERY;
822 		goto out_enable_irq;
823 	}
824 
825 	ts->iap_mode = ELAN_IAP_OPERATIONAL;
826 
827 out_enable_irq:
828 	ts->state = ELAN_STATE_NORMAL;
829 	enable_irq(client->irq);
830 	msleep(100);
831 
832 	if (!error)
833 		elants_i2c_calibrate(ts);
834 out:
835 	release_firmware(fw);
836 	return error;
837 }
838 
839 /*
840  * Event reporting.
841  */
842 
843 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
844 {
845 	struct input_dev *input = ts->input;
846 	unsigned int n_fingers;
847 	unsigned int tool_type;
848 	u16 finger_state;
849 	int i;
850 
851 	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
852 	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
853 			buf[FW_POS_STATE];
854 
855 	dev_dbg(&ts->client->dev,
856 		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
857 
858 	/* Note: all fingers have the same tool type */
859 	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
860 			MT_TOOL_FINGER : MT_TOOL_PALM;
861 
862 	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
863 		if (finger_state & 1) {
864 			unsigned int x, y, p, w;
865 			u8 *pos;
866 
867 			pos = &buf[FW_POS_XY + i * 3];
868 			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
869 			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
870 			p = buf[FW_POS_PRESSURE + i];
871 			w = buf[FW_POS_WIDTH + i];
872 
873 			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
874 				i, x, y, p, w);
875 
876 			input_mt_slot(input, i);
877 			input_mt_report_slot_state(input, tool_type, true);
878 			input_event(input, EV_ABS, ABS_MT_POSITION_X, x);
879 			input_event(input, EV_ABS, ABS_MT_POSITION_Y, y);
880 			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
881 			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
882 
883 			n_fingers--;
884 		}
885 
886 		finger_state >>= 1;
887 	}
888 
889 	input_mt_sync_frame(input);
890 	input_sync(input);
891 }
892 
893 static u8 elants_i2c_calculate_checksum(u8 *buf)
894 {
895 	u8 checksum = 0;
896 	u8 i;
897 
898 	for (i = 0; i < FW_POS_CHECKSUM; i++)
899 		checksum += buf[i];
900 
901 	return checksum;
902 }
903 
904 static void elants_i2c_event(struct elants_data *ts, u8 *buf)
905 {
906 	u8 checksum = elants_i2c_calculate_checksum(buf);
907 
908 	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
909 		dev_warn(&ts->client->dev,
910 			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
911 			 __func__, buf[FW_POS_HEADER],
912 			 checksum, buf[FW_POS_CHECKSUM]);
913 	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
914 		dev_warn(&ts->client->dev,
915 			 "%s: unknown packet type: %02x\n",
916 			 __func__, buf[FW_POS_HEADER]);
917 	else
918 		elants_i2c_mt_event(ts, buf);
919 }
920 
921 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
922 {
923 	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
924 	struct elants_data *ts = _dev;
925 	struct i2c_client *client = ts->client;
926 	int report_count, report_len;
927 	int i;
928 	int len;
929 
930 	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
931 	if (len < 0) {
932 		dev_err(&client->dev, "%s: failed to read data: %d\n",
933 			__func__, len);
934 		goto out;
935 	}
936 
937 	dev_dbg(&client->dev, "%s: packet %*ph\n",
938 		__func__, HEADER_SIZE, ts->buf);
939 
940 	switch (ts->state) {
941 	case ELAN_WAIT_RECALIBRATION:
942 		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
943 			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
944 			complete(&ts->cmd_done);
945 			ts->state = ELAN_STATE_NORMAL;
946 		}
947 		break;
948 
949 	case ELAN_WAIT_QUEUE_HEADER:
950 		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
951 			break;
952 
953 		ts->state = ELAN_STATE_NORMAL;
954 		/* fall through */
955 
956 	case ELAN_STATE_NORMAL:
957 
958 		switch (ts->buf[FW_HDR_TYPE]) {
959 		case CMD_HEADER_HELLO:
960 		case CMD_HEADER_RESP:
961 		case CMD_HEADER_REK:
962 			break;
963 
964 		case QUEUE_HEADER_WAIT:
965 			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
966 				dev_err(&client->dev,
967 					"invalid wait packet %*ph\n",
968 					HEADER_SIZE, ts->buf);
969 			} else {
970 				ts->state = ELAN_WAIT_QUEUE_HEADER;
971 				udelay(30);
972 			}
973 			break;
974 
975 		case QUEUE_HEADER_SINGLE:
976 			elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
977 			break;
978 
979 		case QUEUE_HEADER_NORMAL:
980 			report_count = ts->buf[FW_HDR_COUNT];
981 			if (report_count == 0 || report_count > 3) {
982 				dev_err(&client->dev,
983 					"bad report count: %*ph\n",
984 					HEADER_SIZE, ts->buf);
985 				break;
986 			}
987 
988 			report_len = ts->buf[FW_HDR_LENGTH] / report_count;
989 			if (report_len != PACKET_SIZE) {
990 				dev_err(&client->dev,
991 					"mismatching report length: %*ph\n",
992 					HEADER_SIZE, ts->buf);
993 				break;
994 			}
995 
996 			for (i = 0; i < report_count; i++) {
997 				u8 *buf = ts->buf + HEADER_SIZE +
998 							i * PACKET_SIZE;
999 				elants_i2c_event(ts, buf);
1000 			}
1001 			break;
1002 
1003 		default:
1004 			dev_err(&client->dev, "unknown packet %*ph\n",
1005 				HEADER_SIZE, ts->buf);
1006 			break;
1007 		}
1008 		break;
1009 	}
1010 
1011 out:
1012 	return IRQ_HANDLED;
1013 }
1014 
1015 /*
1016  * sysfs interface
1017  */
1018 static ssize_t calibrate_store(struct device *dev,
1019 			       struct device_attribute *attr,
1020 			      const char *buf, size_t count)
1021 {
1022 	struct i2c_client *client = to_i2c_client(dev);
1023 	struct elants_data *ts = i2c_get_clientdata(client);
1024 	int error;
1025 
1026 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1027 	if (error)
1028 		return error;
1029 
1030 	error = elants_i2c_calibrate(ts);
1031 
1032 	mutex_unlock(&ts->sysfs_mutex);
1033 	return error ?: count;
1034 }
1035 
1036 static ssize_t write_update_fw(struct device *dev,
1037 			       struct device_attribute *attr,
1038 			       const char *buf, size_t count)
1039 {
1040 	struct i2c_client *client = to_i2c_client(dev);
1041 	struct elants_data *ts = i2c_get_clientdata(client);
1042 	int error;
1043 
1044 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1045 	if (error)
1046 		return error;
1047 
1048 	error = elants_i2c_fw_update(ts);
1049 	dev_dbg(dev, "firmware update result: %d\n", error);
1050 
1051 	mutex_unlock(&ts->sysfs_mutex);
1052 	return error ?: count;
1053 }
1054 
1055 static ssize_t show_iap_mode(struct device *dev,
1056 			     struct device_attribute *attr, char *buf)
1057 {
1058 	struct i2c_client *client = to_i2c_client(dev);
1059 	struct elants_data *ts = i2c_get_clientdata(client);
1060 
1061 	return sprintf(buf, "%s\n",
1062 		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
1063 				"Normal" : "Recovery");
1064 }
1065 
1066 static DEVICE_ATTR_WO(calibrate);
1067 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1068 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1069 
1070 struct elants_version_attribute {
1071 	struct device_attribute dattr;
1072 	size_t field_offset;
1073 	size_t field_size;
1074 };
1075 
1076 #define __ELANTS_FIELD_SIZE(_field)					\
1077 	sizeof(((struct elants_data *)NULL)->_field)
1078 #define __ELANTS_VERIFY_SIZE(_field)					\
1079 	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
1080 	 __ELANTS_FIELD_SIZE(_field))
1081 #define ELANTS_VERSION_ATTR(_field)					\
1082 	struct elants_version_attribute elants_ver_attr_##_field = {	\
1083 		.dattr = __ATTR(_field, S_IRUGO,			\
1084 				elants_version_attribute_show, NULL),	\
1085 		.field_offset = offsetof(struct elants_data, _field),	\
1086 		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
1087 	}
1088 
1089 static ssize_t elants_version_attribute_show(struct device *dev,
1090 					     struct device_attribute *dattr,
1091 					     char *buf)
1092 {
1093 	struct i2c_client *client = to_i2c_client(dev);
1094 	struct elants_data *ts = i2c_get_clientdata(client);
1095 	struct elants_version_attribute *attr =
1096 		container_of(dattr, struct elants_version_attribute, dattr);
1097 	u8 *field = (u8 *)((char *)ts + attr->field_offset);
1098 	unsigned int fmt_size;
1099 	unsigned int val;
1100 
1101 	if (attr->field_size == 1) {
1102 		val = *field;
1103 		fmt_size = 2; /* 2 HEX digits */
1104 	} else {
1105 		val = *(u16 *)field;
1106 		fmt_size = 4; /* 4 HEX digits */
1107 	}
1108 
1109 	return sprintf(buf, "%0*x\n", fmt_size, val);
1110 }
1111 
1112 static ELANTS_VERSION_ATTR(fw_version);
1113 static ELANTS_VERSION_ATTR(hw_version);
1114 static ELANTS_VERSION_ATTR(test_version);
1115 static ELANTS_VERSION_ATTR(solution_version);
1116 static ELANTS_VERSION_ATTR(bc_version);
1117 static ELANTS_VERSION_ATTR(iap_version);
1118 
1119 static struct attribute *elants_attributes[] = {
1120 	&dev_attr_calibrate.attr,
1121 	&dev_attr_update_fw.attr,
1122 	&dev_attr_iap_mode.attr,
1123 
1124 	&elants_ver_attr_fw_version.dattr.attr,
1125 	&elants_ver_attr_hw_version.dattr.attr,
1126 	&elants_ver_attr_test_version.dattr.attr,
1127 	&elants_ver_attr_solution_version.dattr.attr,
1128 	&elants_ver_attr_bc_version.dattr.attr,
1129 	&elants_ver_attr_iap_version.dattr.attr,
1130 	NULL
1131 };
1132 
1133 static const struct attribute_group elants_attribute_group = {
1134 	.attrs = elants_attributes,
1135 };
1136 
1137 static int elants_i2c_power_on(struct elants_data *ts)
1138 {
1139 	int error;
1140 
1141 	/*
1142 	 * If we do not have reset gpio assume platform firmware
1143 	 * controls regulators and does power them on for us.
1144 	 */
1145 	if (IS_ERR_OR_NULL(ts->reset_gpio))
1146 		return 0;
1147 
1148 	gpiod_set_value_cansleep(ts->reset_gpio, 1);
1149 
1150 	error = regulator_enable(ts->vcc33);
1151 	if (error) {
1152 		dev_err(&ts->client->dev,
1153 			"failed to enable vcc33 regulator: %d\n",
1154 			error);
1155 		goto release_reset_gpio;
1156 	}
1157 
1158 	error = regulator_enable(ts->vccio);
1159 	if (error) {
1160 		dev_err(&ts->client->dev,
1161 			"failed to enable vccio regulator: %d\n",
1162 			error);
1163 		regulator_disable(ts->vcc33);
1164 		goto release_reset_gpio;
1165 	}
1166 
1167 	/*
1168 	 * We need to wait a bit after powering on controller before
1169 	 * we are allowed to release reset GPIO.
1170 	 */
1171 	udelay(ELAN_POWERON_DELAY_USEC);
1172 
1173 release_reset_gpio:
1174 	gpiod_set_value_cansleep(ts->reset_gpio, 0);
1175 	if (error)
1176 		return error;
1177 
1178 	msleep(ELAN_RESET_DELAY_MSEC);
1179 
1180 	return 0;
1181 }
1182 
1183 static void elants_i2c_power_off(void *_data)
1184 {
1185 	struct elants_data *ts = _data;
1186 
1187 	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1188 		/*
1189 		 * Activate reset gpio to prevent leakage through the
1190 		 * pin once we shut off power to the controller.
1191 		 */
1192 		gpiod_set_value_cansleep(ts->reset_gpio, 1);
1193 		regulator_disable(ts->vccio);
1194 		regulator_disable(ts->vcc33);
1195 	}
1196 }
1197 
1198 static int elants_i2c_probe(struct i2c_client *client,
1199 			    const struct i2c_device_id *id)
1200 {
1201 	union i2c_smbus_data dummy;
1202 	struct elants_data *ts;
1203 	unsigned long irqflags;
1204 	int error;
1205 
1206 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1207 		dev_err(&client->dev,
1208 			"%s: i2c check functionality error\n", DEVICE_NAME);
1209 		return -ENXIO;
1210 	}
1211 
1212 	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1213 	if (!ts)
1214 		return -ENOMEM;
1215 
1216 	mutex_init(&ts->sysfs_mutex);
1217 	init_completion(&ts->cmd_done);
1218 
1219 	ts->client = client;
1220 	i2c_set_clientdata(client, ts);
1221 
1222 	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1223 	if (IS_ERR(ts->vcc33)) {
1224 		error = PTR_ERR(ts->vcc33);
1225 		if (error != -EPROBE_DEFER)
1226 			dev_err(&client->dev,
1227 				"Failed to get 'vcc33' regulator: %d\n",
1228 				error);
1229 		return error;
1230 	}
1231 
1232 	ts->vccio = devm_regulator_get(&client->dev, "vccio");
1233 	if (IS_ERR(ts->vccio)) {
1234 		error = PTR_ERR(ts->vccio);
1235 		if (error != -EPROBE_DEFER)
1236 			dev_err(&client->dev,
1237 				"Failed to get 'vccio' regulator: %d\n",
1238 				error);
1239 		return error;
1240 	}
1241 
1242 	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1243 	if (IS_ERR(ts->reset_gpio)) {
1244 		error = PTR_ERR(ts->reset_gpio);
1245 
1246 		if (error == -EPROBE_DEFER)
1247 			return error;
1248 
1249 		if (error != -ENOENT && error != -ENOSYS) {
1250 			dev_err(&client->dev,
1251 				"failed to get reset gpio: %d\n",
1252 				error);
1253 			return error;
1254 		}
1255 
1256 		ts->keep_power_in_suspend = true;
1257 	}
1258 
1259 	error = elants_i2c_power_on(ts);
1260 	if (error)
1261 		return error;
1262 
1263 	error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1264 	if (error) {
1265 		dev_err(&client->dev,
1266 			"failed to install power off action: %d\n", error);
1267 		elants_i2c_power_off(ts);
1268 		return error;
1269 	}
1270 
1271 	/* Make sure there is something at this address */
1272 	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1273 			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1274 		dev_err(&client->dev, "nothing at this address\n");
1275 		return -ENXIO;
1276 	}
1277 
1278 	error = elants_i2c_initialize(ts);
1279 	if (error) {
1280 		dev_err(&client->dev, "failed to initialize: %d\n", error);
1281 		return error;
1282 	}
1283 
1284 	ts->input = devm_input_allocate_device(&client->dev);
1285 	if (!ts->input) {
1286 		dev_err(&client->dev, "Failed to allocate input device\n");
1287 		return -ENOMEM;
1288 	}
1289 
1290 	ts->input->name = "Elan Touchscreen";
1291 	ts->input->id.bustype = BUS_I2C;
1292 
1293 	__set_bit(BTN_TOUCH, ts->input->keybit);
1294 	__set_bit(EV_ABS, ts->input->evbit);
1295 	__set_bit(EV_KEY, ts->input->evbit);
1296 
1297 	/* Single touch input params setup */
1298 	input_set_abs_params(ts->input, ABS_X, 0, ts->x_max, 0, 0);
1299 	input_set_abs_params(ts->input, ABS_Y, 0, ts->y_max, 0, 0);
1300 	input_set_abs_params(ts->input, ABS_PRESSURE, 0, 255, 0, 0);
1301 	input_abs_set_res(ts->input, ABS_X, ts->x_res);
1302 	input_abs_set_res(ts->input, ABS_Y, ts->y_res);
1303 
1304 	/* Multitouch input params setup */
1305 	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1306 				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1307 	if (error) {
1308 		dev_err(&client->dev,
1309 			"failed to initialize MT slots: %d\n", error);
1310 		return error;
1311 	}
1312 
1313 	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1314 	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1315 	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1316 	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1317 	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
1318 			     0, MT_TOOL_PALM, 0, 0);
1319 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1320 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1321 	input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, 1);
1322 
1323 	error = input_register_device(ts->input);
1324 	if (error) {
1325 		dev_err(&client->dev,
1326 			"unable to register input device: %d\n", error);
1327 		return error;
1328 	}
1329 
1330 	/*
1331 	 * Platform code (ACPI, DTS) should normally set up interrupt
1332 	 * for us, but in case it did not let's fall back to using falling
1333 	 * edge to be compatible with older Chromebooks.
1334 	 */
1335 	irqflags = irq_get_trigger_type(client->irq);
1336 	if (!irqflags)
1337 		irqflags = IRQF_TRIGGER_FALLING;
1338 
1339 	error = devm_request_threaded_irq(&client->dev, client->irq,
1340 					  NULL, elants_i2c_irq,
1341 					  irqflags | IRQF_ONESHOT,
1342 					  client->name, ts);
1343 	if (error) {
1344 		dev_err(&client->dev, "Failed to register interrupt\n");
1345 		return error;
1346 	}
1347 
1348 	/*
1349 	 * Systems using device tree should set up wakeup via DTS,
1350 	 * the rest will configure device as wakeup source by default.
1351 	 */
1352 	if (!client->dev.of_node)
1353 		device_init_wakeup(&client->dev, true);
1354 
1355 	error = devm_device_add_group(&client->dev, &elants_attribute_group);
1356 	if (error) {
1357 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1358 			error);
1359 		return error;
1360 	}
1361 
1362 	return 0;
1363 }
1364 
1365 static int __maybe_unused elants_i2c_suspend(struct device *dev)
1366 {
1367 	struct i2c_client *client = to_i2c_client(dev);
1368 	struct elants_data *ts = i2c_get_clientdata(client);
1369 	const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
1370 	int retry_cnt;
1371 	int error;
1372 
1373 	/* Command not support in IAP recovery mode */
1374 	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1375 		return -EBUSY;
1376 
1377 	disable_irq(client->irq);
1378 
1379 	if (device_may_wakeup(dev)) {
1380 		/*
1381 		 * The device will automatically enter idle mode
1382 		 * that has reduced power consumption.
1383 		 */
1384 		ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1385 	} else if (ts->keep_power_in_suspend) {
1386 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1387 			error = elants_i2c_send(client, set_sleep_cmd,
1388 						sizeof(set_sleep_cmd));
1389 			if (!error)
1390 				break;
1391 
1392 			dev_err(&client->dev,
1393 				"suspend command failed: %d\n", error);
1394 		}
1395 	} else {
1396 		elants_i2c_power_off(ts);
1397 	}
1398 
1399 	return 0;
1400 }
1401 
1402 static int __maybe_unused elants_i2c_resume(struct device *dev)
1403 {
1404 	struct i2c_client *client = to_i2c_client(dev);
1405 	struct elants_data *ts = i2c_get_clientdata(client);
1406 	const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
1407 	int retry_cnt;
1408 	int error;
1409 
1410 	if (device_may_wakeup(dev)) {
1411 		if (ts->wake_irq_enabled)
1412 			disable_irq_wake(client->irq);
1413 		elants_i2c_sw_reset(client);
1414 	} else if (ts->keep_power_in_suspend) {
1415 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1416 			error = elants_i2c_send(client, set_active_cmd,
1417 						sizeof(set_active_cmd));
1418 			if (!error)
1419 				break;
1420 
1421 			dev_err(&client->dev,
1422 				"resume command failed: %d\n", error);
1423 		}
1424 	} else {
1425 		elants_i2c_power_on(ts);
1426 		elants_i2c_initialize(ts);
1427 	}
1428 
1429 	ts->state = ELAN_STATE_NORMAL;
1430 	enable_irq(client->irq);
1431 
1432 	return 0;
1433 }
1434 
1435 static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1436 			 elants_i2c_suspend, elants_i2c_resume);
1437 
1438 static const struct i2c_device_id elants_i2c_id[] = {
1439 	{ DEVICE_NAME, 0 },
1440 	{ }
1441 };
1442 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1443 
1444 #ifdef CONFIG_ACPI
1445 static const struct acpi_device_id elants_acpi_id[] = {
1446 	{ "ELAN0001", 0 },
1447 	{ }
1448 };
1449 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1450 #endif
1451 
1452 #ifdef CONFIG_OF
1453 static const struct of_device_id elants_of_match[] = {
1454 	{ .compatible = "elan,ekth3500" },
1455 	{ /* sentinel */ }
1456 };
1457 MODULE_DEVICE_TABLE(of, elants_of_match);
1458 #endif
1459 
1460 static struct i2c_driver elants_i2c_driver = {
1461 	.probe = elants_i2c_probe,
1462 	.id_table = elants_i2c_id,
1463 	.driver = {
1464 		.name = DEVICE_NAME,
1465 		.pm = &elants_i2c_pm_ops,
1466 		.acpi_match_table = ACPI_PTR(elants_acpi_id),
1467 		.of_match_table = of_match_ptr(elants_of_match),
1468 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1469 	},
1470 };
1471 module_i2c_driver(elants_i2c_driver);
1472 
1473 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1474 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1475 MODULE_LICENSE("GPL");
1476