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/input/touchscreen.h>
37 #include <linux/acpi.h>
38 #include <linux/of.h>
39 #include <linux/gpio/consumer.h>
40 #include <linux/regulator/consumer.h>
41 #include <asm/unaligned.h>
42 
43 /* Device, Driver information */
44 #define DEVICE_NAME	"elants_i2c"
45 
46 /* Convert from rows or columns into resolution */
47 #define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
48 
49 /* FW header data */
50 #define HEADER_SIZE		4
51 #define FW_HDR_TYPE		0
52 #define FW_HDR_COUNT		1
53 #define FW_HDR_LENGTH		2
54 
55 /* Buffer mode Queue Header information */
56 #define QUEUE_HEADER_SINGLE	0x62
57 #define QUEUE_HEADER_NORMAL	0X63
58 #define QUEUE_HEADER_WAIT	0x64
59 
60 /* Command header definition */
61 #define CMD_HEADER_WRITE	0x54
62 #define CMD_HEADER_READ		0x53
63 #define CMD_HEADER_6B_READ	0x5B
64 #define CMD_HEADER_ROM_READ	0x96
65 #define CMD_HEADER_RESP		0x52
66 #define CMD_HEADER_6B_RESP	0x9B
67 #define CMD_HEADER_ROM_RESP	0x95
68 #define CMD_HEADER_HELLO	0x55
69 #define CMD_HEADER_REK		0x66
70 
71 /* FW position data */
72 #define PACKET_SIZE		55
73 #define MAX_CONTACT_NUM		10
74 #define FW_POS_HEADER		0
75 #define FW_POS_STATE		1
76 #define FW_POS_TOTAL		2
77 #define FW_POS_XY		3
78 #define FW_POS_TOOL_TYPE	33
79 #define FW_POS_CHECKSUM		34
80 #define FW_POS_WIDTH		35
81 #define FW_POS_PRESSURE		45
82 
83 #define HEADER_REPORT_10_FINGER	0x62
84 
85 /* Header (4 bytes) plus 3 fill 10-finger packets */
86 #define MAX_PACKET_SIZE		169
87 
88 #define BOOT_TIME_DELAY_MS	50
89 
90 /* FW read command, 0x53 0x?? 0x0, 0x01 */
91 #define E_ELAN_INFO_FW_VER	0x00
92 #define E_ELAN_INFO_BC_VER	0x10
93 #define E_ELAN_INFO_REK		0xE0
94 #define E_ELAN_INFO_TEST_VER	0xE0
95 #define E_ELAN_INFO_FW_ID	0xF0
96 #define E_INFO_OSR		0xD6
97 #define E_INFO_PHY_SCAN		0xD7
98 #define E_INFO_PHY_DRIVER	0xD8
99 
100 #define MAX_RETRIES		3
101 #define MAX_FW_UPDATE_RETRIES	30
102 
103 #define ELAN_FW_PAGESIZE	132
104 
105 /* calibration timeout definition */
106 #define ELAN_CALI_TIMEOUT_MSEC	12000
107 
108 #define ELAN_POWERON_DELAY_USEC	500
109 #define ELAN_RESET_DELAY_MSEC	20
110 
111 enum elants_state {
112 	ELAN_STATE_NORMAL,
113 	ELAN_WAIT_QUEUE_HEADER,
114 	ELAN_WAIT_RECALIBRATION,
115 };
116 
117 enum elants_iap_mode {
118 	ELAN_IAP_OPERATIONAL,
119 	ELAN_IAP_RECOVERY,
120 };
121 
122 /* struct elants_data - represents state of Elan touchscreen device */
123 struct elants_data {
124 	struct i2c_client *client;
125 	struct input_dev *input;
126 
127 	struct regulator *vcc33;
128 	struct regulator *vccio;
129 	struct gpio_desc *reset_gpio;
130 
131 	u16 fw_version;
132 	u8 test_version;
133 	u8 solution_version;
134 	u8 bc_version;
135 	u8 iap_version;
136 	u16 hw_version;
137 	unsigned int x_res;	/* resolution in units/mm */
138 	unsigned int y_res;
139 	unsigned int x_max;
140 	unsigned int y_max;
141 	struct touchscreen_properties prop;
142 
143 	enum elants_state state;
144 	enum elants_iap_mode iap_mode;
145 
146 	/* Guards against concurrent access to the device via sysfs */
147 	struct mutex sysfs_mutex;
148 
149 	u8 cmd_resp[HEADER_SIZE];
150 	struct completion cmd_done;
151 
152 	bool wake_irq_enabled;
153 	bool keep_power_in_suspend;
154 
155 	/* Must be last to be used for DMA operations */
156 	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
157 };
158 
159 static int elants_i2c_send(struct i2c_client *client,
160 			   const void *data, size_t size)
161 {
162 	int ret;
163 
164 	ret = i2c_master_send(client, data, size);
165 	if (ret == size)
166 		return 0;
167 
168 	if (ret >= 0)
169 		ret = -EIO;
170 
171 	dev_err(&client->dev, "%s failed (%*ph): %d\n",
172 		__func__, (int)size, data, ret);
173 
174 	return ret;
175 }
176 
177 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
178 {
179 	int ret;
180 
181 	ret = i2c_master_recv(client, data, size);
182 	if (ret == size)
183 		return 0;
184 
185 	if (ret >= 0)
186 		ret = -EIO;
187 
188 	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
189 
190 	return ret;
191 }
192 
193 static int elants_i2c_execute_command(struct i2c_client *client,
194 				      const u8 *cmd, size_t cmd_size,
195 				      u8 *resp, size_t resp_size,
196 				      int retries, const char *cmd_name)
197 {
198 	struct i2c_msg msgs[2];
199 	int ret;
200 	u8 expected_response;
201 
202 	switch (cmd[0]) {
203 	case CMD_HEADER_READ:
204 		expected_response = CMD_HEADER_RESP;
205 		break;
206 
207 	case CMD_HEADER_6B_READ:
208 		expected_response = CMD_HEADER_6B_RESP;
209 		break;
210 
211 	case CMD_HEADER_ROM_READ:
212 		expected_response = CMD_HEADER_ROM_RESP;
213 		break;
214 
215 	default:
216 		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
217 			cmd_name, (int)cmd_size, cmd);
218 		return -EINVAL;
219 	}
220 
221 	for (;;) {
222 		msgs[0].addr = client->addr;
223 		msgs[0].flags = client->flags & I2C_M_TEN;
224 		msgs[0].len = cmd_size;
225 		msgs[0].buf = (u8 *)cmd;
226 
227 		msgs[1].addr = client->addr;
228 		msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
229 		msgs[1].flags |= I2C_M_RD;
230 		msgs[1].len = resp_size;
231 		msgs[1].buf = resp;
232 
233 		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
234 		if (ret < 0) {
235 			if (--retries > 0) {
236 				dev_dbg(&client->dev,
237 					"(%s) I2C transfer failed: %pe (retrying)\n",
238 					cmd_name, ERR_PTR(ret));
239 				continue;
240 			}
241 
242 			dev_err(&client->dev,
243 				"(%s) I2C transfer failed: %pe\n",
244 				cmd_name, ERR_PTR(ret));
245 			return ret;
246 		}
247 
248 		if (ret != ARRAY_SIZE(msgs) ||
249 		    resp[FW_HDR_TYPE] != expected_response) {
250 			if (--retries > 0) {
251 				dev_dbg(&client->dev,
252 					"(%s) unexpected response: %*ph (retrying)\n",
253 					cmd_name, ret, resp);
254 				continue;
255 			}
256 
257 			dev_err(&client->dev,
258 				"(%s) unexpected response: %*ph\n",
259 				cmd_name, ret, resp);
260 			return -EIO;
261 		}
262 
263 		return 0;
264 	}
265 }
266 
267 static int elants_i2c_calibrate(struct elants_data *ts)
268 {
269 	struct i2c_client *client = ts->client;
270 	int ret, error;
271 	static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
272 	static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
273 	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
274 
275 	disable_irq(client->irq);
276 
277 	ts->state = ELAN_WAIT_RECALIBRATION;
278 	reinit_completion(&ts->cmd_done);
279 
280 	elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
281 	elants_i2c_send(client, rek, sizeof(rek));
282 
283 	enable_irq(client->irq);
284 
285 	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
286 				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
287 
288 	ts->state = ELAN_STATE_NORMAL;
289 
290 	if (ret <= 0) {
291 		error = ret < 0 ? ret : -ETIMEDOUT;
292 		dev_err(&client->dev,
293 			"error while waiting for calibration to complete: %d\n",
294 			error);
295 		return error;
296 	}
297 
298 	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
299 		dev_err(&client->dev,
300 			"unexpected calibration response: %*ph\n",
301 			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
302 		return -EINVAL;
303 	}
304 
305 	return 0;
306 }
307 
308 static int elants_i2c_sw_reset(struct i2c_client *client)
309 {
310 	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
311 	int error;
312 
313 	error = elants_i2c_send(client, soft_rst_cmd,
314 				sizeof(soft_rst_cmd));
315 	if (error) {
316 		dev_err(&client->dev, "software reset failed: %d\n", error);
317 		return error;
318 	}
319 
320 	/*
321 	 * We should wait at least 10 msec (but no more than 40) before
322 	 * sending fastboot or IAP command to the device.
323 	 */
324 	msleep(30);
325 
326 	return 0;
327 }
328 
329 static u16 elants_i2c_parse_version(u8 *buf)
330 {
331 	return get_unaligned_be32(buf) >> 4;
332 }
333 
334 static int elants_i2c_query_hw_version(struct elants_data *ts)
335 {
336 	struct i2c_client *client = ts->client;
337 	int retry_cnt = MAX_RETRIES;
338 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
339 	u8 resp[HEADER_SIZE];
340 	int error;
341 
342 	while (retry_cnt--) {
343 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
344 						   resp, sizeof(resp), 1,
345 						   "read fw id");
346 		if (error)
347 			return error;
348 
349 		ts->hw_version = elants_i2c_parse_version(resp);
350 		if (ts->hw_version != 0xffff)
351 			return 0;
352 	}
353 
354 	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
355 
356 	return -EINVAL;
357 }
358 
359 static int elants_i2c_query_fw_version(struct elants_data *ts)
360 {
361 	struct i2c_client *client = ts->client;
362 	int retry_cnt = MAX_RETRIES;
363 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
364 	u8 resp[HEADER_SIZE];
365 	int error;
366 
367 	while (retry_cnt--) {
368 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
369 						   resp, sizeof(resp), 1,
370 						   "read fw version");
371 		if (error)
372 			return error;
373 
374 		ts->fw_version = elants_i2c_parse_version(resp);
375 		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
376 			return 0;
377 
378 		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
379 			(int)sizeof(resp), resp);
380 	}
381 
382 	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
383 
384 	return -EINVAL;
385 }
386 
387 static int elants_i2c_query_test_version(struct elants_data *ts)
388 {
389 	struct i2c_client *client = ts->client;
390 	int error;
391 	u16 version;
392 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
393 	u8 resp[HEADER_SIZE];
394 
395 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
396 					   resp, sizeof(resp), MAX_RETRIES,
397 					   "read test version");
398 	if (error) {
399 		dev_err(&client->dev, "Failed to read test version\n");
400 		return error;
401 	}
402 
403 	version = elants_i2c_parse_version(resp);
404 	ts->test_version = version >> 8;
405 	ts->solution_version = version & 0xff;
406 
407 	return 0;
408 }
409 
410 static int elants_i2c_query_bc_version(struct elants_data *ts)
411 {
412 	struct i2c_client *client = ts->client;
413 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
414 	u8 resp[HEADER_SIZE];
415 	u16 version;
416 	int error;
417 
418 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
419 					   resp, sizeof(resp), 1,
420 					   "read BC version");
421 	if (error)
422 		return error;
423 
424 	version = elants_i2c_parse_version(resp);
425 	ts->bc_version = version >> 8;
426 	ts->iap_version = version & 0xff;
427 
428 	return 0;
429 }
430 
431 static int elants_i2c_query_ts_info(struct elants_data *ts)
432 {
433 	struct i2c_client *client = ts->client;
434 	int error;
435 	u8 resp[17];
436 	u16 phy_x, phy_y, rows, cols, osr;
437 	const u8 get_resolution_cmd[] = {
438 		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
439 	};
440 	const u8 get_osr_cmd[] = {
441 		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
442 	};
443 	const u8 get_physical_scan_cmd[] = {
444 		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
445 	};
446 	const u8 get_physical_drive_cmd[] = {
447 		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
448 	};
449 
450 	/* Get trace number */
451 	error = elants_i2c_execute_command(client,
452 					   get_resolution_cmd,
453 					   sizeof(get_resolution_cmd),
454 					   resp, sizeof(resp), 1,
455 					   "get resolution");
456 	if (error)
457 		return error;
458 
459 	rows = resp[2] + resp[6] + resp[10];
460 	cols = resp[3] + resp[7] + resp[11];
461 
462 	/* Process mm_to_pixel information */
463 	error = elants_i2c_execute_command(client,
464 					   get_osr_cmd, sizeof(get_osr_cmd),
465 					   resp, sizeof(resp), 1, "get osr");
466 	if (error)
467 		return error;
468 
469 	osr = resp[3];
470 
471 	error = elants_i2c_execute_command(client,
472 					   get_physical_scan_cmd,
473 					   sizeof(get_physical_scan_cmd),
474 					   resp, sizeof(resp), 1,
475 					   "get physical scan");
476 	if (error)
477 		return error;
478 
479 	phy_x = get_unaligned_be16(&resp[2]);
480 
481 	error = elants_i2c_execute_command(client,
482 					   get_physical_drive_cmd,
483 					   sizeof(get_physical_drive_cmd),
484 					   resp, sizeof(resp), 1,
485 					   "get physical drive");
486 	if (error)
487 		return error;
488 
489 	phy_y = get_unaligned_be16(&resp[2]);
490 
491 	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
492 
493 	if (rows == 0 || cols == 0 || osr == 0) {
494 		dev_warn(&client->dev,
495 			 "invalid trace number data: %d, %d, %d\n",
496 			 rows, cols, osr);
497 	} else {
498 		/* translate trace number to TS resolution */
499 		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
500 		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
501 		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
502 		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
503 	}
504 
505 	return 0;
506 }
507 
508 static int elants_i2c_fastboot(struct i2c_client *client)
509 {
510 	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
511 	int error;
512 
513 	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
514 	if (error) {
515 		dev_err(&client->dev, "boot failed: %d\n", error);
516 		return error;
517 	}
518 
519 	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
520 	return 0;
521 }
522 
523 static int elants_i2c_initialize(struct elants_data *ts)
524 {
525 	struct i2c_client *client = ts->client;
526 	int error, error2, retry_cnt;
527 	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
528 	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
529 	u8 buf[HEADER_SIZE];
530 
531 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
532 		error = elants_i2c_sw_reset(client);
533 		if (error) {
534 			/* Continue initializing if it's the last try */
535 			if (retry_cnt < MAX_RETRIES - 1)
536 				continue;
537 		}
538 
539 		error = elants_i2c_fastboot(client);
540 		if (error) {
541 			/* Continue initializing if it's the last try */
542 			if (retry_cnt < MAX_RETRIES - 1)
543 				continue;
544 		}
545 
546 		/* Wait for Hello packet */
547 		msleep(BOOT_TIME_DELAY_MS);
548 
549 		error = elants_i2c_read(client, buf, sizeof(buf));
550 		if (error) {
551 			dev_err(&client->dev,
552 				"failed to read 'hello' packet: %d\n", error);
553 		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
554 			ts->iap_mode = ELAN_IAP_OPERATIONAL;
555 			break;
556 		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
557 			/*
558 			 * Setting error code will mark device
559 			 * in recovery mode below.
560 			 */
561 			error = -EIO;
562 			break;
563 		} else {
564 			error = -EINVAL;
565 			dev_err(&client->dev,
566 				"invalid 'hello' packet: %*ph\n",
567 				(int)sizeof(buf), buf);
568 		}
569 	}
570 
571 	/* hw version is available even if device in recovery state */
572 	error2 = elants_i2c_query_hw_version(ts);
573 	if (!error2)
574 		error2 = elants_i2c_query_bc_version(ts);
575 	if (!error)
576 		error = error2;
577 
578 	if (!error)
579 		error = elants_i2c_query_fw_version(ts);
580 	if (!error)
581 		error = elants_i2c_query_test_version(ts);
582 	if (!error)
583 		error = elants_i2c_query_ts_info(ts);
584 
585 	if (error)
586 		ts->iap_mode = ELAN_IAP_RECOVERY;
587 
588 	return 0;
589 }
590 
591 /*
592  * Firmware update interface.
593  */
594 
595 static int elants_i2c_fw_write_page(struct i2c_client *client,
596 				    const void *page)
597 {
598 	const u8 ack_ok[] = { 0xaa, 0xaa };
599 	u8 buf[2];
600 	int retry;
601 	int error;
602 
603 	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
604 		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
605 		if (error) {
606 			dev_err(&client->dev,
607 				"IAP Write Page failed: %d\n", error);
608 			continue;
609 		}
610 
611 		error = elants_i2c_read(client, buf, 2);
612 		if (error) {
613 			dev_err(&client->dev,
614 				"IAP Ack read failed: %d\n", error);
615 			return error;
616 		}
617 
618 		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
619 			return 0;
620 
621 		error = -EIO;
622 		dev_err(&client->dev,
623 			"IAP Get Ack Error [%02x:%02x]\n",
624 			buf[0], buf[1]);
625 	}
626 
627 	return error;
628 }
629 
630 static int elants_i2c_validate_remark_id(struct elants_data *ts,
631 					 const struct firmware *fw)
632 {
633 	struct i2c_client *client = ts->client;
634 	int error;
635 	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
636 	u8 resp[6] = { 0 };
637 	u16 ts_remark_id = 0;
638 	u16 fw_remark_id = 0;
639 
640 	/* Compare TS Remark ID and FW Remark ID */
641 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
642 					   resp, sizeof(resp),
643 					   1, "read Remark ID");
644 	if (error)
645 		return error;
646 
647 	ts_remark_id = get_unaligned_be16(&resp[3]);
648 
649 	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
650 
651 	if (fw_remark_id != ts_remark_id) {
652 		dev_err(&client->dev,
653 			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
654 			ts_remark_id, fw_remark_id);
655 		return -EINVAL;
656 	}
657 
658 	return 0;
659 }
660 
661 static int elants_i2c_do_update_firmware(struct i2c_client *client,
662 					 const struct firmware *fw,
663 					 bool force)
664 {
665 	struct elants_data *ts = i2c_get_clientdata(client);
666 	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
667 	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
668 	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
669 	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
670 	u8 buf[HEADER_SIZE];
671 	u16 send_id;
672 	int page, n_fw_pages;
673 	int error;
674 	bool check_remark_id = ts->iap_version >= 0x60;
675 
676 	/* Recovery mode detection! */
677 	if (force) {
678 		dev_dbg(&client->dev, "Recovery mode procedure\n");
679 
680 		if (check_remark_id) {
681 			error = elants_i2c_validate_remark_id(ts, fw);
682 			if (error)
683 				return error;
684 		}
685 
686 		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
687 		if (error) {
688 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
689 				error);
690 			return error;
691 		}
692 	} else {
693 		/* Start IAP Procedure */
694 		dev_dbg(&client->dev, "Normal IAP procedure\n");
695 
696 		/* Close idle mode */
697 		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
698 		if (error)
699 			dev_err(&client->dev, "Failed close idle: %d\n", error);
700 		msleep(60);
701 
702 		elants_i2c_sw_reset(client);
703 		msleep(20);
704 
705 		if (check_remark_id) {
706 			error = elants_i2c_validate_remark_id(ts, fw);
707 			if (error)
708 				return error;
709 		}
710 
711 		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
712 		if (error) {
713 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
714 				error);
715 			return error;
716 		}
717 	}
718 
719 	msleep(20);
720 
721 	/* check IAP state */
722 	error = elants_i2c_read(client, buf, 4);
723 	if (error) {
724 		dev_err(&client->dev,
725 			"failed to read IAP acknowledgement: %d\n",
726 			error);
727 		return error;
728 	}
729 
730 	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
731 		dev_err(&client->dev,
732 			"failed to enter IAP: %*ph (expected %*ph)\n",
733 			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
734 		return -EIO;
735 	}
736 
737 	dev_info(&client->dev, "successfully entered IAP mode");
738 
739 	send_id = client->addr;
740 	error = elants_i2c_send(client, &send_id, 1);
741 	if (error) {
742 		dev_err(&client->dev, "sending dummy byte failed: %d\n",
743 			error);
744 		return error;
745 	}
746 
747 	/* Clear the last page of Master */
748 	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
749 	if (error) {
750 		dev_err(&client->dev, "clearing of the last page failed: %d\n",
751 			error);
752 		return error;
753 	}
754 
755 	error = elants_i2c_read(client, buf, 2);
756 	if (error) {
757 		dev_err(&client->dev,
758 			"failed to read ACK for clearing the last page: %d\n",
759 			error);
760 		return error;
761 	}
762 
763 	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
764 	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
765 
766 	for (page = 0; page < n_fw_pages; page++) {
767 		error = elants_i2c_fw_write_page(client,
768 					fw->data + page * ELAN_FW_PAGESIZE);
769 		if (error) {
770 			dev_err(&client->dev,
771 				"failed to write FW page %d: %d\n",
772 				page, error);
773 			return error;
774 		}
775 	}
776 
777 	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
778 	msleep(300);
779 
780 	dev_info(&client->dev, "firmware update completed\n");
781 	return 0;
782 }
783 
784 static int elants_i2c_fw_update(struct elants_data *ts)
785 {
786 	struct i2c_client *client = ts->client;
787 	const struct firmware *fw;
788 	char *fw_name;
789 	int error;
790 
791 	fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
792 	if (!fw_name)
793 		return -ENOMEM;
794 
795 	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
796 	error = request_firmware(&fw, fw_name, &client->dev);
797 	kfree(fw_name);
798 	if (error) {
799 		dev_err(&client->dev, "failed to request firmware: %d\n",
800 			error);
801 		return error;
802 	}
803 
804 	if (fw->size % ELAN_FW_PAGESIZE) {
805 		dev_err(&client->dev, "invalid firmware length: %zu\n",
806 			fw->size);
807 		error = -EINVAL;
808 		goto out;
809 	}
810 
811 	disable_irq(client->irq);
812 
813 	error = elants_i2c_do_update_firmware(client, fw,
814 					ts->iap_mode == ELAN_IAP_RECOVERY);
815 	if (error) {
816 		dev_err(&client->dev, "firmware update failed: %d\n", error);
817 		ts->iap_mode = ELAN_IAP_RECOVERY;
818 		goto out_enable_irq;
819 	}
820 
821 	error = elants_i2c_initialize(ts);
822 	if (error) {
823 		dev_err(&client->dev,
824 			"failed to initialize device after firmware update: %d\n",
825 			error);
826 		ts->iap_mode = ELAN_IAP_RECOVERY;
827 		goto out_enable_irq;
828 	}
829 
830 	ts->iap_mode = ELAN_IAP_OPERATIONAL;
831 
832 out_enable_irq:
833 	ts->state = ELAN_STATE_NORMAL;
834 	enable_irq(client->irq);
835 	msleep(100);
836 
837 	if (!error)
838 		elants_i2c_calibrate(ts);
839 out:
840 	release_firmware(fw);
841 	return error;
842 }
843 
844 /*
845  * Event reporting.
846  */
847 
848 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
849 {
850 	struct input_dev *input = ts->input;
851 	unsigned int n_fingers;
852 	unsigned int tool_type;
853 	u16 finger_state;
854 	int i;
855 
856 	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
857 	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
858 			buf[FW_POS_STATE];
859 
860 	dev_dbg(&ts->client->dev,
861 		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
862 
863 	/* Note: all fingers have the same tool type */
864 	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
865 			MT_TOOL_FINGER : MT_TOOL_PALM;
866 
867 	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
868 		if (finger_state & 1) {
869 			unsigned int x, y, p, w;
870 			u8 *pos;
871 
872 			pos = &buf[FW_POS_XY + i * 3];
873 			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
874 			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
875 			p = buf[FW_POS_PRESSURE + i];
876 			w = buf[FW_POS_WIDTH + i];
877 
878 			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
879 				i, x, y, p, w);
880 
881 			input_mt_slot(input, i);
882 			input_mt_report_slot_state(input, tool_type, true);
883 			touchscreen_report_pos(input, &ts->prop, x, y, true);
884 			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
885 			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
886 
887 			n_fingers--;
888 		}
889 
890 		finger_state >>= 1;
891 	}
892 
893 	input_mt_sync_frame(input);
894 	input_sync(input);
895 }
896 
897 static u8 elants_i2c_calculate_checksum(u8 *buf)
898 {
899 	u8 checksum = 0;
900 	u8 i;
901 
902 	for (i = 0; i < FW_POS_CHECKSUM; i++)
903 		checksum += buf[i];
904 
905 	return checksum;
906 }
907 
908 static void elants_i2c_event(struct elants_data *ts, u8 *buf)
909 {
910 	u8 checksum = elants_i2c_calculate_checksum(buf);
911 
912 	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
913 		dev_warn(&ts->client->dev,
914 			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
915 			 __func__, buf[FW_POS_HEADER],
916 			 checksum, buf[FW_POS_CHECKSUM]);
917 	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
918 		dev_warn(&ts->client->dev,
919 			 "%s: unknown packet type: %02x\n",
920 			 __func__, buf[FW_POS_HEADER]);
921 	else
922 		elants_i2c_mt_event(ts, buf);
923 }
924 
925 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
926 {
927 	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
928 	struct elants_data *ts = _dev;
929 	struct i2c_client *client = ts->client;
930 	int report_count, report_len;
931 	int i;
932 	int len;
933 
934 	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
935 	if (len < 0) {
936 		dev_err(&client->dev, "%s: failed to read data: %d\n",
937 			__func__, len);
938 		goto out;
939 	}
940 
941 	dev_dbg(&client->dev, "%s: packet %*ph\n",
942 		__func__, HEADER_SIZE, ts->buf);
943 
944 	switch (ts->state) {
945 	case ELAN_WAIT_RECALIBRATION:
946 		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
947 			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
948 			complete(&ts->cmd_done);
949 			ts->state = ELAN_STATE_NORMAL;
950 		}
951 		break;
952 
953 	case ELAN_WAIT_QUEUE_HEADER:
954 		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
955 			break;
956 
957 		ts->state = ELAN_STATE_NORMAL;
958 		/* fall through */
959 
960 	case ELAN_STATE_NORMAL:
961 
962 		switch (ts->buf[FW_HDR_TYPE]) {
963 		case CMD_HEADER_HELLO:
964 		case CMD_HEADER_RESP:
965 		case CMD_HEADER_REK:
966 			break;
967 
968 		case QUEUE_HEADER_WAIT:
969 			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
970 				dev_err(&client->dev,
971 					"invalid wait packet %*ph\n",
972 					HEADER_SIZE, ts->buf);
973 			} else {
974 				ts->state = ELAN_WAIT_QUEUE_HEADER;
975 				udelay(30);
976 			}
977 			break;
978 
979 		case QUEUE_HEADER_SINGLE:
980 			elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
981 			break;
982 
983 		case QUEUE_HEADER_NORMAL:
984 			report_count = ts->buf[FW_HDR_COUNT];
985 			if (report_count == 0 || report_count > 3) {
986 				dev_err(&client->dev,
987 					"bad report count: %*ph\n",
988 					HEADER_SIZE, ts->buf);
989 				break;
990 			}
991 
992 			report_len = ts->buf[FW_HDR_LENGTH] / report_count;
993 			if (report_len != PACKET_SIZE) {
994 				dev_err(&client->dev,
995 					"mismatching report length: %*ph\n",
996 					HEADER_SIZE, ts->buf);
997 				break;
998 			}
999 
1000 			for (i = 0; i < report_count; i++) {
1001 				u8 *buf = ts->buf + HEADER_SIZE +
1002 							i * PACKET_SIZE;
1003 				elants_i2c_event(ts, buf);
1004 			}
1005 			break;
1006 
1007 		default:
1008 			dev_err(&client->dev, "unknown packet %*ph\n",
1009 				HEADER_SIZE, ts->buf);
1010 			break;
1011 		}
1012 		break;
1013 	}
1014 
1015 out:
1016 	return IRQ_HANDLED;
1017 }
1018 
1019 /*
1020  * sysfs interface
1021  */
1022 static ssize_t calibrate_store(struct device *dev,
1023 			       struct device_attribute *attr,
1024 			       const char *buf, size_t count)
1025 {
1026 	struct i2c_client *client = to_i2c_client(dev);
1027 	struct elants_data *ts = i2c_get_clientdata(client);
1028 	int error;
1029 
1030 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1031 	if (error)
1032 		return error;
1033 
1034 	error = elants_i2c_calibrate(ts);
1035 
1036 	mutex_unlock(&ts->sysfs_mutex);
1037 	return error ?: count;
1038 }
1039 
1040 static ssize_t write_update_fw(struct device *dev,
1041 			       struct device_attribute *attr,
1042 			       const char *buf, size_t count)
1043 {
1044 	struct i2c_client *client = to_i2c_client(dev);
1045 	struct elants_data *ts = i2c_get_clientdata(client);
1046 	int error;
1047 
1048 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1049 	if (error)
1050 		return error;
1051 
1052 	error = elants_i2c_fw_update(ts);
1053 	dev_dbg(dev, "firmware update result: %d\n", error);
1054 
1055 	mutex_unlock(&ts->sysfs_mutex);
1056 	return error ?: count;
1057 }
1058 
1059 static ssize_t show_iap_mode(struct device *dev,
1060 			     struct device_attribute *attr, char *buf)
1061 {
1062 	struct i2c_client *client = to_i2c_client(dev);
1063 	struct elants_data *ts = i2c_get_clientdata(client);
1064 
1065 	return sprintf(buf, "%s\n",
1066 		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
1067 				"Normal" : "Recovery");
1068 }
1069 
1070 static ssize_t show_calibration_count(struct device *dev,
1071 				      struct device_attribute *attr, char *buf)
1072 {
1073 	struct i2c_client *client = to_i2c_client(dev);
1074 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
1075 	u8 resp[HEADER_SIZE];
1076 	u16 rek_count;
1077 	int error;
1078 
1079 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
1080 					   resp, sizeof(resp), 1,
1081 					   "read ReK status");
1082 	if (error)
1083 		return sprintf(buf, "%d\n", error);
1084 
1085 	rek_count = get_unaligned_be16(&resp[2]);
1086 	return sprintf(buf, "0x%04x\n", rek_count);
1087 }
1088 
1089 static DEVICE_ATTR_WO(calibrate);
1090 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1091 static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
1092 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1093 
1094 struct elants_version_attribute {
1095 	struct device_attribute dattr;
1096 	size_t field_offset;
1097 	size_t field_size;
1098 };
1099 
1100 #define __ELANTS_FIELD_SIZE(_field)					\
1101 	sizeof(((struct elants_data *)NULL)->_field)
1102 #define __ELANTS_VERIFY_SIZE(_field)					\
1103 	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
1104 	 __ELANTS_FIELD_SIZE(_field))
1105 #define ELANTS_VERSION_ATTR(_field)					\
1106 	struct elants_version_attribute elants_ver_attr_##_field = {	\
1107 		.dattr = __ATTR(_field, S_IRUGO,			\
1108 				elants_version_attribute_show, NULL),	\
1109 		.field_offset = offsetof(struct elants_data, _field),	\
1110 		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
1111 	}
1112 
1113 static ssize_t elants_version_attribute_show(struct device *dev,
1114 					     struct device_attribute *dattr,
1115 					     char *buf)
1116 {
1117 	struct i2c_client *client = to_i2c_client(dev);
1118 	struct elants_data *ts = i2c_get_clientdata(client);
1119 	struct elants_version_attribute *attr =
1120 		container_of(dattr, struct elants_version_attribute, dattr);
1121 	u8 *field = (u8 *)((char *)ts + attr->field_offset);
1122 	unsigned int fmt_size;
1123 	unsigned int val;
1124 
1125 	if (attr->field_size == 1) {
1126 		val = *field;
1127 		fmt_size = 2; /* 2 HEX digits */
1128 	} else {
1129 		val = *(u16 *)field;
1130 		fmt_size = 4; /* 4 HEX digits */
1131 	}
1132 
1133 	return sprintf(buf, "%0*x\n", fmt_size, val);
1134 }
1135 
1136 static ELANTS_VERSION_ATTR(fw_version);
1137 static ELANTS_VERSION_ATTR(hw_version);
1138 static ELANTS_VERSION_ATTR(test_version);
1139 static ELANTS_VERSION_ATTR(solution_version);
1140 static ELANTS_VERSION_ATTR(bc_version);
1141 static ELANTS_VERSION_ATTR(iap_version);
1142 
1143 static struct attribute *elants_attributes[] = {
1144 	&dev_attr_calibrate.attr,
1145 	&dev_attr_update_fw.attr,
1146 	&dev_attr_iap_mode.attr,
1147 	&dev_attr_calibration_count.attr,
1148 
1149 	&elants_ver_attr_fw_version.dattr.attr,
1150 	&elants_ver_attr_hw_version.dattr.attr,
1151 	&elants_ver_attr_test_version.dattr.attr,
1152 	&elants_ver_attr_solution_version.dattr.attr,
1153 	&elants_ver_attr_bc_version.dattr.attr,
1154 	&elants_ver_attr_iap_version.dattr.attr,
1155 	NULL
1156 };
1157 
1158 static const struct attribute_group elants_attribute_group = {
1159 	.attrs = elants_attributes,
1160 };
1161 
1162 static int elants_i2c_power_on(struct elants_data *ts)
1163 {
1164 	int error;
1165 
1166 	/*
1167 	 * If we do not have reset gpio assume platform firmware
1168 	 * controls regulators and does power them on for us.
1169 	 */
1170 	if (IS_ERR_OR_NULL(ts->reset_gpio))
1171 		return 0;
1172 
1173 	gpiod_set_value_cansleep(ts->reset_gpio, 1);
1174 
1175 	error = regulator_enable(ts->vcc33);
1176 	if (error) {
1177 		dev_err(&ts->client->dev,
1178 			"failed to enable vcc33 regulator: %d\n",
1179 			error);
1180 		goto release_reset_gpio;
1181 	}
1182 
1183 	error = regulator_enable(ts->vccio);
1184 	if (error) {
1185 		dev_err(&ts->client->dev,
1186 			"failed to enable vccio regulator: %d\n",
1187 			error);
1188 		regulator_disable(ts->vcc33);
1189 		goto release_reset_gpio;
1190 	}
1191 
1192 	/*
1193 	 * We need to wait a bit after powering on controller before
1194 	 * we are allowed to release reset GPIO.
1195 	 */
1196 	udelay(ELAN_POWERON_DELAY_USEC);
1197 
1198 release_reset_gpio:
1199 	gpiod_set_value_cansleep(ts->reset_gpio, 0);
1200 	if (error)
1201 		return error;
1202 
1203 	msleep(ELAN_RESET_DELAY_MSEC);
1204 
1205 	return 0;
1206 }
1207 
1208 static void elants_i2c_power_off(void *_data)
1209 {
1210 	struct elants_data *ts = _data;
1211 
1212 	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1213 		/*
1214 		 * Activate reset gpio to prevent leakage through the
1215 		 * pin once we shut off power to the controller.
1216 		 */
1217 		gpiod_set_value_cansleep(ts->reset_gpio, 1);
1218 		regulator_disable(ts->vccio);
1219 		regulator_disable(ts->vcc33);
1220 	}
1221 }
1222 
1223 static int elants_i2c_probe(struct i2c_client *client,
1224 			    const struct i2c_device_id *id)
1225 {
1226 	union i2c_smbus_data dummy;
1227 	struct elants_data *ts;
1228 	unsigned long irqflags;
1229 	int error;
1230 
1231 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1232 		dev_err(&client->dev,
1233 			"%s: i2c check functionality error\n", DEVICE_NAME);
1234 		return -ENXIO;
1235 	}
1236 
1237 	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1238 	if (!ts)
1239 		return -ENOMEM;
1240 
1241 	mutex_init(&ts->sysfs_mutex);
1242 	init_completion(&ts->cmd_done);
1243 
1244 	ts->client = client;
1245 	i2c_set_clientdata(client, ts);
1246 
1247 	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1248 	if (IS_ERR(ts->vcc33)) {
1249 		error = PTR_ERR(ts->vcc33);
1250 		if (error != -EPROBE_DEFER)
1251 			dev_err(&client->dev,
1252 				"Failed to get 'vcc33' regulator: %d\n",
1253 				error);
1254 		return error;
1255 	}
1256 
1257 	ts->vccio = devm_regulator_get(&client->dev, "vccio");
1258 	if (IS_ERR(ts->vccio)) {
1259 		error = PTR_ERR(ts->vccio);
1260 		if (error != -EPROBE_DEFER)
1261 			dev_err(&client->dev,
1262 				"Failed to get 'vccio' regulator: %d\n",
1263 				error);
1264 		return error;
1265 	}
1266 
1267 	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1268 	if (IS_ERR(ts->reset_gpio)) {
1269 		error = PTR_ERR(ts->reset_gpio);
1270 
1271 		if (error == -EPROBE_DEFER)
1272 			return error;
1273 
1274 		if (error != -ENOENT && error != -ENOSYS) {
1275 			dev_err(&client->dev,
1276 				"failed to get reset gpio: %d\n",
1277 				error);
1278 			return error;
1279 		}
1280 
1281 		ts->keep_power_in_suspend = true;
1282 	}
1283 
1284 	error = elants_i2c_power_on(ts);
1285 	if (error)
1286 		return error;
1287 
1288 	error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1289 	if (error) {
1290 		dev_err(&client->dev,
1291 			"failed to install power off action: %d\n", error);
1292 		elants_i2c_power_off(ts);
1293 		return error;
1294 	}
1295 
1296 	/* Make sure there is something at this address */
1297 	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1298 			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1299 		dev_err(&client->dev, "nothing at this address\n");
1300 		return -ENXIO;
1301 	}
1302 
1303 	error = elants_i2c_initialize(ts);
1304 	if (error) {
1305 		dev_err(&client->dev, "failed to initialize: %d\n", error);
1306 		return error;
1307 	}
1308 
1309 	ts->input = devm_input_allocate_device(&client->dev);
1310 	if (!ts->input) {
1311 		dev_err(&client->dev, "Failed to allocate input device\n");
1312 		return -ENOMEM;
1313 	}
1314 
1315 	ts->input->name = "Elan Touchscreen";
1316 	ts->input->id.bustype = BUS_I2C;
1317 
1318 	/* Multitouch input params setup */
1319 
1320 	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1321 	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1322 	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1323 	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1324 	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
1325 			     0, MT_TOOL_PALM, 0, 0);
1326 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1327 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1328 
1329 	touchscreen_parse_properties(ts->input, true, &ts->prop);
1330 
1331 	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1332 				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1333 	if (error) {
1334 		dev_err(&client->dev,
1335 			"failed to initialize MT slots: %d\n", error);
1336 		return error;
1337 	}
1338 
1339 	error = input_register_device(ts->input);
1340 	if (error) {
1341 		dev_err(&client->dev,
1342 			"unable to register input device: %d\n", error);
1343 		return error;
1344 	}
1345 
1346 	/*
1347 	 * Platform code (ACPI, DTS) should normally set up interrupt
1348 	 * for us, but in case it did not let's fall back to using falling
1349 	 * edge to be compatible with older Chromebooks.
1350 	 */
1351 	irqflags = irq_get_trigger_type(client->irq);
1352 	if (!irqflags)
1353 		irqflags = IRQF_TRIGGER_FALLING;
1354 
1355 	error = devm_request_threaded_irq(&client->dev, client->irq,
1356 					  NULL, elants_i2c_irq,
1357 					  irqflags | IRQF_ONESHOT,
1358 					  client->name, ts);
1359 	if (error) {
1360 		dev_err(&client->dev, "Failed to register interrupt\n");
1361 		return error;
1362 	}
1363 
1364 	/*
1365 	 * Systems using device tree should set up wakeup via DTS,
1366 	 * the rest will configure device as wakeup source by default.
1367 	 */
1368 	if (!client->dev.of_node)
1369 		device_init_wakeup(&client->dev, true);
1370 
1371 	error = devm_device_add_group(&client->dev, &elants_attribute_group);
1372 	if (error) {
1373 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1374 			error);
1375 		return error;
1376 	}
1377 
1378 	return 0;
1379 }
1380 
1381 static int __maybe_unused elants_i2c_suspend(struct device *dev)
1382 {
1383 	struct i2c_client *client = to_i2c_client(dev);
1384 	struct elants_data *ts = i2c_get_clientdata(client);
1385 	const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
1386 	int retry_cnt;
1387 	int error;
1388 
1389 	/* Command not support in IAP recovery mode */
1390 	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1391 		return -EBUSY;
1392 
1393 	disable_irq(client->irq);
1394 
1395 	if (device_may_wakeup(dev)) {
1396 		/*
1397 		 * The device will automatically enter idle mode
1398 		 * that has reduced power consumption.
1399 		 */
1400 		ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1401 	} else if (ts->keep_power_in_suspend) {
1402 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1403 			error = elants_i2c_send(client, set_sleep_cmd,
1404 						sizeof(set_sleep_cmd));
1405 			if (!error)
1406 				break;
1407 
1408 			dev_err(&client->dev,
1409 				"suspend command failed: %d\n", error);
1410 		}
1411 	} else {
1412 		elants_i2c_power_off(ts);
1413 	}
1414 
1415 	return 0;
1416 }
1417 
1418 static int __maybe_unused elants_i2c_resume(struct device *dev)
1419 {
1420 	struct i2c_client *client = to_i2c_client(dev);
1421 	struct elants_data *ts = i2c_get_clientdata(client);
1422 	const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
1423 	int retry_cnt;
1424 	int error;
1425 
1426 	if (device_may_wakeup(dev)) {
1427 		if (ts->wake_irq_enabled)
1428 			disable_irq_wake(client->irq);
1429 		elants_i2c_sw_reset(client);
1430 	} else if (ts->keep_power_in_suspend) {
1431 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1432 			error = elants_i2c_send(client, set_active_cmd,
1433 						sizeof(set_active_cmd));
1434 			if (!error)
1435 				break;
1436 
1437 			dev_err(&client->dev,
1438 				"resume command failed: %d\n", error);
1439 		}
1440 	} else {
1441 		elants_i2c_power_on(ts);
1442 		elants_i2c_initialize(ts);
1443 	}
1444 
1445 	ts->state = ELAN_STATE_NORMAL;
1446 	enable_irq(client->irq);
1447 
1448 	return 0;
1449 }
1450 
1451 static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1452 			 elants_i2c_suspend, elants_i2c_resume);
1453 
1454 static const struct i2c_device_id elants_i2c_id[] = {
1455 	{ DEVICE_NAME, 0 },
1456 	{ }
1457 };
1458 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1459 
1460 #ifdef CONFIG_ACPI
1461 static const struct acpi_device_id elants_acpi_id[] = {
1462 	{ "ELAN0001", 0 },
1463 	{ }
1464 };
1465 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1466 #endif
1467 
1468 #ifdef CONFIG_OF
1469 static const struct of_device_id elants_of_match[] = {
1470 	{ .compatible = "elan,ekth3500" },
1471 	{ /* sentinel */ }
1472 };
1473 MODULE_DEVICE_TABLE(of, elants_of_match);
1474 #endif
1475 
1476 static struct i2c_driver elants_i2c_driver = {
1477 	.probe = elants_i2c_probe,
1478 	.id_table = elants_i2c_id,
1479 	.driver = {
1480 		.name = DEVICE_NAME,
1481 		.pm = &elants_i2c_pm_ops,
1482 		.acpi_match_table = ACPI_PTR(elants_acpi_id),
1483 		.of_match_table = of_match_ptr(elants_of_match),
1484 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1485 	},
1486 };
1487 module_i2c_driver(elants_i2c_driver);
1488 
1489 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1490 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1491 MODULE_LICENSE("GPL");
1492