xref: /linux/drivers/input/touchscreen/elants_i2c.c (revision ffd01c3bcc1af4d8c3e7949152af0d9fe3d1fda5)
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/pm_wakeirq.h>
40 #include <linux/gpio/consumer.h>
41 #include <linux/regulator/consumer.h>
42 #include <linux/uuid.h>
43 #include <linux/unaligned.h>
44 
45 /* Device, Driver information */
46 #define DEVICE_NAME	"elants_i2c"
47 
48 /* Convert from rows or columns into resolution */
49 #define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
50 
51 /* FW header data */
52 #define HEADER_SIZE		4
53 #define FW_HDR_TYPE		0
54 #define FW_HDR_COUNT		1
55 #define FW_HDR_LENGTH		2
56 
57 /* Buffer mode Queue Header information */
58 #define QUEUE_HEADER_SINGLE	0x62
59 #define QUEUE_HEADER_NORMAL	0X63
60 #define QUEUE_HEADER_WAIT	0x64
61 #define QUEUE_HEADER_NORMAL2	0x66
62 
63 /* Command header definition */
64 #define CMD_HEADER_WRITE	0x54
65 #define CMD_HEADER_READ		0x53
66 #define CMD_HEADER_6B_READ	0x5B
67 #define CMD_HEADER_ROM_READ	0x96
68 #define CMD_HEADER_RESP		0x52
69 #define CMD_HEADER_6B_RESP	0x9B
70 #define CMD_HEADER_ROM_RESP	0x95
71 #define CMD_HEADER_HELLO	0x55
72 #define CMD_HEADER_REK		0x66
73 
74 /* FW position data */
75 #define PACKET_SIZE_OLD		40
76 #define PACKET_SIZE		55
77 #define MAX_CONTACT_NUM		10
78 #define FW_POS_HEADER		0
79 #define FW_POS_STATE		1
80 #define FW_POS_TOTAL		2
81 #define FW_POS_XY		3
82 #define FW_POS_TOOL_TYPE	33
83 #define FW_POS_CHECKSUM		34
84 #define FW_POS_WIDTH		35
85 #define FW_POS_PRESSURE		45
86 
87 #define HEADER_REPORT_10_FINGER	0x62
88 
89 /* Header (4 bytes) plus 3 full 10-finger packets */
90 #define MAX_PACKET_SIZE		169
91 
92 #define BOOT_TIME_DELAY_MS	50
93 
94 /* FW read command, 0x53 0x?? 0x0, 0x01 */
95 #define E_ELAN_INFO_FW_VER	0x00
96 #define E_ELAN_INFO_BC_VER	0x10
97 #define E_ELAN_INFO_X_RES	0x60
98 #define E_ELAN_INFO_Y_RES	0x63
99 #define E_ELAN_INFO_REK		0xD0
100 #define E_ELAN_INFO_TEST_VER	0xE0
101 #define E_ELAN_INFO_FW_ID	0xF0
102 #define E_INFO_OSR		0xD6
103 #define E_INFO_PHY_SCAN		0xD7
104 #define E_INFO_PHY_DRIVER	0xD8
105 
106 /* FW write command, 0x54 0x?? 0x0, 0x01 */
107 #define E_POWER_STATE_SLEEP	0x50
108 #define E_POWER_STATE_RESUME	0x58
109 
110 #define MAX_RETRIES		3
111 #define MAX_FW_UPDATE_RETRIES	30
112 
113 #define ELAN_FW_PAGESIZE	132
114 
115 /* calibration timeout definition */
116 #define ELAN_CALI_TIMEOUT_MSEC	12000
117 
118 #define ELAN_POWERON_DELAY_USEC	5000
119 #define ELAN_RESET_DELAY_MSEC	20
120 
121 /* FW boot code version */
122 #define BC_VER_H_BYTE_FOR_EKTH3900x1_I2C        0x72
123 #define BC_VER_H_BYTE_FOR_EKTH3900x2_I2C        0x82
124 #define BC_VER_H_BYTE_FOR_EKTH3900x3_I2C        0x92
125 #define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C        0x6D
126 #define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C        0x6E
127 #define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C       0x77
128 #define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C       0x78
129 #define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB    0x67
130 #define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB    0x68
131 #define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB   0x74
132 #define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB   0x75
133 
134 enum elants_chip_id {
135 	EKTH3500,
136 	EKTF3624,
137 };
138 
139 enum elants_state {
140 	ELAN_STATE_NORMAL,
141 	ELAN_WAIT_QUEUE_HEADER,
142 	ELAN_WAIT_RECALIBRATION,
143 };
144 
145 enum elants_iap_mode {
146 	ELAN_IAP_OPERATIONAL,
147 	ELAN_IAP_RECOVERY,
148 };
149 
150 /* struct elants_data - represents state of Elan touchscreen device */
151 struct elants_data {
152 	struct i2c_client *client;
153 	struct input_dev *input;
154 
155 	struct regulator *vcc33;
156 	struct regulator *vccio;
157 	struct gpio_desc *reset_gpio;
158 
159 	u16 fw_version;
160 	u8 test_version;
161 	u8 solution_version;
162 	u8 bc_version;
163 	u8 iap_version;
164 	u16 hw_version;
165 	u8 major_res;
166 	unsigned int x_res;	/* resolution in units/mm */
167 	unsigned int y_res;
168 	unsigned int x_max;
169 	unsigned int y_max;
170 	unsigned int phy_x;
171 	unsigned int phy_y;
172 	struct touchscreen_properties prop;
173 
174 	enum elants_state state;
175 	enum elants_chip_id chip_id;
176 	enum elants_iap_mode iap_mode;
177 
178 	/* Guards against concurrent access to the device via sysfs */
179 	struct mutex sysfs_mutex;
180 
181 	u8 cmd_resp[HEADER_SIZE];
182 	struct completion cmd_done;
183 
184 	bool keep_power_in_suspend;
185 
186 	/* Must be last to be used for DMA operations */
187 	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
188 };
189 
190 static int elants_i2c_send(struct i2c_client *client,
191 			   const void *data, size_t size)
192 {
193 	int ret;
194 
195 	ret = i2c_master_send(client, data, size);
196 	if (ret == size)
197 		return 0;
198 
199 	if (ret >= 0)
200 		ret = -EIO;
201 
202 	dev_err(&client->dev, "%s failed (%*ph): %d\n",
203 		__func__, (int)size, data, ret);
204 
205 	return ret;
206 }
207 
208 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
209 {
210 	int ret;
211 
212 	ret = i2c_master_recv(client, data, size);
213 	if (ret == size)
214 		return 0;
215 
216 	if (ret >= 0)
217 		ret = -EIO;
218 
219 	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
220 
221 	return ret;
222 }
223 
224 static int elants_i2c_execute_command(struct i2c_client *client,
225 				      const u8 *cmd, size_t cmd_size,
226 				      u8 *resp, size_t resp_size,
227 				      int retries, const char *cmd_name)
228 {
229 	struct i2c_msg msgs[2];
230 	int ret;
231 	u8 expected_response;
232 
233 	switch (cmd[0]) {
234 	case CMD_HEADER_READ:
235 		expected_response = CMD_HEADER_RESP;
236 		break;
237 
238 	case CMD_HEADER_6B_READ:
239 		expected_response = CMD_HEADER_6B_RESP;
240 		break;
241 
242 	case CMD_HEADER_ROM_READ:
243 		expected_response = CMD_HEADER_ROM_RESP;
244 		break;
245 
246 	default:
247 		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
248 			cmd_name, (int)cmd_size, cmd);
249 		return -EINVAL;
250 	}
251 
252 	for (;;) {
253 		msgs[0].addr = client->addr;
254 		msgs[0].flags = client->flags & I2C_M_TEN;
255 		msgs[0].len = cmd_size;
256 		msgs[0].buf = (u8 *)cmd;
257 
258 		msgs[1].addr = client->addr;
259 		msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
260 		msgs[1].flags |= I2C_M_RD;
261 		msgs[1].len = resp_size;
262 		msgs[1].buf = resp;
263 
264 		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
265 		if (ret < 0) {
266 			if (--retries > 0) {
267 				dev_dbg(&client->dev,
268 					"(%s) I2C transfer failed: %pe (retrying)\n",
269 					cmd_name, ERR_PTR(ret));
270 				continue;
271 			}
272 
273 			dev_err(&client->dev,
274 				"(%s) I2C transfer failed: %pe\n",
275 				cmd_name, ERR_PTR(ret));
276 			return ret;
277 		}
278 
279 		if (ret != ARRAY_SIZE(msgs) ||
280 		    resp[FW_HDR_TYPE] != expected_response) {
281 			if (--retries > 0) {
282 				dev_dbg(&client->dev,
283 					"(%s) unexpected response: %*ph (retrying)\n",
284 					cmd_name, ret, resp);
285 				continue;
286 			}
287 
288 			dev_err(&client->dev,
289 				"(%s) unexpected response: %*ph\n",
290 				cmd_name, ret, resp);
291 			return -EIO;
292 		}
293 
294 		return 0;
295 	}
296 }
297 
298 static int elants_i2c_calibrate(struct elants_data *ts)
299 {
300 	struct i2c_client *client = ts->client;
301 	int ret, error;
302 	static const u8 w_flashkey[] = { CMD_HEADER_WRITE, 0xC0, 0xE1, 0x5A };
303 	static const u8 rek[] = { CMD_HEADER_WRITE, 0x29, 0x00, 0x01 };
304 	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
305 
306 	scoped_guard(disable_irq, &client->irq) {
307 		ts->state = ELAN_WAIT_RECALIBRATION;
308 		reinit_completion(&ts->cmd_done);
309 
310 		elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
311 		elants_i2c_send(client, rek, sizeof(rek));
312 	}
313 
314 	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
315 				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
316 
317 	ts->state = ELAN_STATE_NORMAL;
318 
319 	if (ret <= 0) {
320 		error = ret < 0 ? ret : -ETIMEDOUT;
321 		dev_err(&client->dev,
322 			"error while waiting for calibration to complete: %d\n",
323 			error);
324 		return error;
325 	}
326 
327 	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
328 		dev_err(&client->dev,
329 			"unexpected calibration response: %*ph\n",
330 			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
331 		return -EINVAL;
332 	}
333 
334 	return 0;
335 }
336 
337 static int elants_i2c_sw_reset(struct i2c_client *client)
338 {
339 	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
340 	int error;
341 
342 	error = elants_i2c_send(client, soft_rst_cmd,
343 				sizeof(soft_rst_cmd));
344 	if (error) {
345 		dev_err(&client->dev, "software reset failed: %d\n", error);
346 		return error;
347 	}
348 
349 	/*
350 	 * We should wait at least 10 msec (but no more than 40) before
351 	 * sending fastboot or IAP command to the device.
352 	 */
353 	msleep(30);
354 
355 	return 0;
356 }
357 
358 static u16 elants_i2c_parse_version(u8 *buf)
359 {
360 	return get_unaligned_be32(buf) >> 4;
361 }
362 
363 static int elants_i2c_query_hw_version(struct elants_data *ts)
364 {
365 	struct i2c_client *client = ts->client;
366 	int retry_cnt = MAX_RETRIES;
367 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
368 	u8 resp[HEADER_SIZE];
369 	int error;
370 
371 	while (retry_cnt--) {
372 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
373 						   resp, sizeof(resp), 1,
374 						   "read fw id");
375 		if (error)
376 			return error;
377 
378 		ts->hw_version = elants_i2c_parse_version(resp);
379 		if (ts->hw_version != 0xffff)
380 			return 0;
381 	}
382 
383 	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
384 
385 	return -EINVAL;
386 }
387 
388 static int elants_i2c_query_fw_version(struct elants_data *ts)
389 {
390 	struct i2c_client *client = ts->client;
391 	int retry_cnt = MAX_RETRIES;
392 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
393 	u8 resp[HEADER_SIZE];
394 	int error;
395 
396 	while (retry_cnt--) {
397 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
398 						   resp, sizeof(resp), 1,
399 						   "read fw version");
400 		if (error)
401 			return error;
402 
403 		ts->fw_version = elants_i2c_parse_version(resp);
404 		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
405 			return 0;
406 
407 		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
408 			(int)sizeof(resp), resp);
409 	}
410 
411 	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
412 
413 	return -EINVAL;
414 }
415 
416 static int elants_i2c_query_test_version(struct elants_data *ts)
417 {
418 	struct i2c_client *client = ts->client;
419 	int error;
420 	u16 version;
421 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
422 	u8 resp[HEADER_SIZE];
423 
424 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
425 					   resp, sizeof(resp), MAX_RETRIES,
426 					   "read test version");
427 	if (error) {
428 		dev_err(&client->dev, "Failed to read test version\n");
429 		return error;
430 	}
431 
432 	version = elants_i2c_parse_version(resp);
433 	ts->test_version = version >> 8;
434 	ts->solution_version = version & 0xff;
435 
436 	return 0;
437 }
438 
439 static int elants_i2c_query_bc_version(struct elants_data *ts)
440 {
441 	struct i2c_client *client = ts->client;
442 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
443 	u8 resp[HEADER_SIZE];
444 	u16 version;
445 	int error;
446 
447 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
448 					   resp, sizeof(resp), 1,
449 					   "read BC version");
450 	if (error)
451 		return error;
452 
453 	version = elants_i2c_parse_version(resp);
454 	ts->bc_version = version >> 8;
455 	ts->iap_version = version & 0xff;
456 
457 	return 0;
458 }
459 
460 static int elants_i2c_query_ts_info_ektf(struct elants_data *ts)
461 {
462 	struct i2c_client *client = ts->client;
463 	int error;
464 	u8 resp[4];
465 	u16 phy_x, phy_y;
466 	const u8 get_xres_cmd[] = {
467 		CMD_HEADER_READ, E_ELAN_INFO_X_RES, 0x00, 0x00
468 	};
469 	const u8 get_yres_cmd[] = {
470 		CMD_HEADER_READ, E_ELAN_INFO_Y_RES, 0x00, 0x00
471 	};
472 
473 	/* Get X/Y size in mm */
474 	error = elants_i2c_execute_command(client, get_xres_cmd,
475 					   sizeof(get_xres_cmd),
476 					   resp, sizeof(resp), 1,
477 					   "get X size");
478 	if (error)
479 		return error;
480 
481 	phy_x = resp[2] | ((resp[3] & 0xF0) << 4);
482 
483 	error = elants_i2c_execute_command(client, get_yres_cmd,
484 					   sizeof(get_yres_cmd),
485 					   resp, sizeof(resp), 1,
486 					   "get Y size");
487 	if (error)
488 		return error;
489 
490 	phy_y = resp[2] | ((resp[3] & 0xF0) << 4);
491 
492 	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
493 
494 	ts->phy_x = phy_x;
495 	ts->phy_y = phy_y;
496 
497 	/* eKTF doesn't report max size, set it to default values */
498 	ts->x_max = 2240 - 1;
499 	ts->y_max = 1408 - 1;
500 
501 	return 0;
502 }
503 
504 static int elants_i2c_query_ts_info_ekth(struct elants_data *ts)
505 {
506 	struct i2c_client *client = ts->client;
507 	int error;
508 	u8 resp[17];
509 	u16 phy_x, phy_y, rows, cols, osr;
510 	const u8 get_resolution_cmd[] = {
511 		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
512 	};
513 	const u8 get_osr_cmd[] = {
514 		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
515 	};
516 	const u8 get_physical_scan_cmd[] = {
517 		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
518 	};
519 	const u8 get_physical_drive_cmd[] = {
520 		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
521 	};
522 
523 	/* Get trace number */
524 	error = elants_i2c_execute_command(client,
525 					   get_resolution_cmd,
526 					   sizeof(get_resolution_cmd),
527 					   resp, sizeof(resp), 1,
528 					   "get resolution");
529 	if (error)
530 		return error;
531 
532 	rows = resp[2] + resp[6] + resp[10];
533 	cols = resp[3] + resp[7] + resp[11];
534 
535 	/* Get report resolution value of ABS_MT_TOUCH_MAJOR */
536 	ts->major_res = resp[16];
537 
538 	/* Process mm_to_pixel information */
539 	error = elants_i2c_execute_command(client,
540 					   get_osr_cmd, sizeof(get_osr_cmd),
541 					   resp, sizeof(resp), 1, "get osr");
542 	if (error)
543 		return error;
544 
545 	osr = resp[3];
546 
547 	error = elants_i2c_execute_command(client,
548 					   get_physical_scan_cmd,
549 					   sizeof(get_physical_scan_cmd),
550 					   resp, sizeof(resp), 1,
551 					   "get physical scan");
552 	if (error)
553 		return error;
554 
555 	phy_x = get_unaligned_be16(&resp[2]);
556 
557 	error = elants_i2c_execute_command(client,
558 					   get_physical_drive_cmd,
559 					   sizeof(get_physical_drive_cmd),
560 					   resp, sizeof(resp), 1,
561 					   "get physical drive");
562 	if (error)
563 		return error;
564 
565 	phy_y = get_unaligned_be16(&resp[2]);
566 
567 	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
568 
569 	if (rows == 0 || cols == 0 || osr == 0) {
570 		dev_warn(&client->dev,
571 			 "invalid trace number data: %d, %d, %d\n",
572 			 rows, cols, osr);
573 	} else {
574 		/* translate trace number to TS resolution */
575 		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
576 		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
577 		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
578 		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
579 		ts->phy_x = phy_x;
580 		ts->phy_y = phy_y;
581 	}
582 
583 	return 0;
584 }
585 
586 static int elants_i2c_fastboot(struct i2c_client *client)
587 {
588 	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
589 	int error;
590 
591 	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
592 	if (error) {
593 		dev_err(&client->dev, "boot failed: %d\n", error);
594 		return error;
595 	}
596 
597 	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
598 	return 0;
599 }
600 
601 static int elants_i2c_initialize(struct elants_data *ts)
602 {
603 	struct i2c_client *client = ts->client;
604 	int error, error2, retry_cnt;
605 	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
606 	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
607 	u8 buf[HEADER_SIZE];
608 
609 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
610 		error = elants_i2c_sw_reset(client);
611 		if (error) {
612 			/* Continue initializing if it's the last try */
613 			if (retry_cnt < MAX_RETRIES - 1)
614 				continue;
615 		}
616 
617 		error = elants_i2c_fastboot(client);
618 		if (error) {
619 			/* Continue initializing if it's the last try */
620 			if (retry_cnt < MAX_RETRIES - 1)
621 				continue;
622 		}
623 
624 		/* Wait for Hello packet */
625 		msleep(BOOT_TIME_DELAY_MS);
626 
627 		error = elants_i2c_read(client, buf, sizeof(buf));
628 		if (error) {
629 			dev_err(&client->dev,
630 				"failed to read 'hello' packet: %d\n", error);
631 		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
632 			ts->iap_mode = ELAN_IAP_OPERATIONAL;
633 			break;
634 		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
635 			/*
636 			 * Setting error code will mark device
637 			 * in recovery mode below.
638 			 */
639 			error = -EIO;
640 			break;
641 		} else {
642 			error = -EINVAL;
643 			dev_err(&client->dev,
644 				"invalid 'hello' packet: %*ph\n",
645 				(int)sizeof(buf), buf);
646 		}
647 	}
648 
649 	/* hw version is available even if device in recovery state */
650 	error2 = elants_i2c_query_hw_version(ts);
651 	if (!error2)
652 		error2 = elants_i2c_query_bc_version(ts);
653 	if (!error)
654 		error = error2;
655 
656 	if (!error)
657 		error = elants_i2c_query_fw_version(ts);
658 	if (!error)
659 		error = elants_i2c_query_test_version(ts);
660 
661 	switch (ts->chip_id) {
662 	case EKTH3500:
663 		if (!error)
664 			error = elants_i2c_query_ts_info_ekth(ts);
665 		break;
666 	case EKTF3624:
667 		if (!error)
668 			error = elants_i2c_query_ts_info_ektf(ts);
669 		break;
670 	default:
671 		BUG();
672 	}
673 
674 	if (error)
675 		ts->iap_mode = ELAN_IAP_RECOVERY;
676 
677 	return 0;
678 }
679 
680 /*
681  * Firmware update interface.
682  */
683 
684 static int elants_i2c_fw_write_page(struct i2c_client *client,
685 				    const void *page)
686 {
687 	const u8 ack_ok[] = { 0xaa, 0xaa };
688 	u8 buf[2];
689 	int retry;
690 	int error;
691 
692 	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
693 		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
694 		if (error) {
695 			dev_err(&client->dev,
696 				"IAP Write Page failed: %d\n", error);
697 			continue;
698 		}
699 
700 		error = elants_i2c_read(client, buf, 2);
701 		if (error) {
702 			dev_err(&client->dev,
703 				"IAP Ack read failed: %d\n", error);
704 			return error;
705 		}
706 
707 		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
708 			return 0;
709 
710 		error = -EIO;
711 		dev_err(&client->dev,
712 			"IAP Get Ack Error [%02x:%02x]\n",
713 			buf[0], buf[1]);
714 	}
715 
716 	return error;
717 }
718 
719 static int elants_i2c_validate_remark_id(struct elants_data *ts,
720 					 const struct firmware *fw)
721 {
722 	struct i2c_client *client = ts->client;
723 	int error;
724 	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
725 	u8 resp[6] = { 0 };
726 	u16 ts_remark_id = 0;
727 	u16 fw_remark_id = 0;
728 
729 	/* Compare TS Remark ID and FW Remark ID */
730 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
731 					   resp, sizeof(resp),
732 					   1, "read Remark ID");
733 	if (error)
734 		return error;
735 
736 	ts_remark_id = get_unaligned_be16(&resp[3]);
737 
738 	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
739 
740 	if (fw_remark_id != ts_remark_id) {
741 		dev_err(&client->dev,
742 			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
743 			ts_remark_id, fw_remark_id);
744 		return -EINVAL;
745 	}
746 
747 	return 0;
748 }
749 
750 static bool elants_i2c_should_check_remark_id(struct elants_data *ts)
751 {
752 	struct i2c_client *client = ts->client;
753 	const u8 bootcode_version = ts->iap_version;
754 	bool check;
755 
756 	/* I2C eKTH3900 and eKTH5312 are NOT support Remark ID */
757 	if ((bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x1_I2C) ||
758 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x2_I2C) ||
759 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x3_I2C) ||
760 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C) ||
761 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C) ||
762 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C) ||
763 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C) ||
764 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB) ||
765 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB) ||
766 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB) ||
767 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB)) {
768 		dev_dbg(&client->dev,
769 			"eKTH3900/eKTH5312(0x%02x) are not support remark id\n",
770 			bootcode_version);
771 		check = false;
772 	} else if (bootcode_version >= 0x60) {
773 		check = true;
774 	} else {
775 		check = false;
776 	}
777 
778 	return check;
779 }
780 
781 static int elants_i2c_do_update_firmware(struct i2c_client *client,
782 					 const struct firmware *fw,
783 					 bool force)
784 {
785 	struct elants_data *ts = i2c_get_clientdata(client);
786 	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
787 	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
788 	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
789 	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
790 	u8 buf[HEADER_SIZE];
791 	u16 send_id;
792 	int page, n_fw_pages;
793 	int error;
794 	bool check_remark_id = elants_i2c_should_check_remark_id(ts);
795 
796 	/* Recovery mode detection! */
797 	if (force) {
798 		dev_dbg(&client->dev, "Recovery mode procedure\n");
799 
800 		if (check_remark_id) {
801 			error = elants_i2c_validate_remark_id(ts, fw);
802 			if (error)
803 				return error;
804 		}
805 
806 		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
807 		if (error) {
808 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
809 				error);
810 			return error;
811 		}
812 	} else {
813 		/* Start IAP Procedure */
814 		dev_dbg(&client->dev, "Normal IAP procedure\n");
815 
816 		/* Close idle mode */
817 		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
818 		if (error)
819 			dev_err(&client->dev, "Failed close idle: %d\n", error);
820 		msleep(60);
821 
822 		elants_i2c_sw_reset(client);
823 		msleep(20);
824 
825 		if (check_remark_id) {
826 			error = elants_i2c_validate_remark_id(ts, fw);
827 			if (error)
828 				return error;
829 		}
830 
831 		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
832 		if (error) {
833 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
834 				error);
835 			return error;
836 		}
837 	}
838 
839 	msleep(20);
840 
841 	/* check IAP state */
842 	error = elants_i2c_read(client, buf, 4);
843 	if (error) {
844 		dev_err(&client->dev,
845 			"failed to read IAP acknowledgement: %d\n",
846 			error);
847 		return error;
848 	}
849 
850 	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
851 		dev_err(&client->dev,
852 			"failed to enter IAP: %*ph (expected %*ph)\n",
853 			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
854 		return -EIO;
855 	}
856 
857 	dev_info(&client->dev, "successfully entered IAP mode");
858 
859 	send_id = client->addr;
860 	error = elants_i2c_send(client, &send_id, 1);
861 	if (error) {
862 		dev_err(&client->dev, "sending dummy byte failed: %d\n",
863 			error);
864 		return error;
865 	}
866 
867 	/* Clear the last page of Master */
868 	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
869 	if (error) {
870 		dev_err(&client->dev, "clearing of the last page failed: %d\n",
871 			error);
872 		return error;
873 	}
874 
875 	error = elants_i2c_read(client, buf, 2);
876 	if (error) {
877 		dev_err(&client->dev,
878 			"failed to read ACK for clearing the last page: %d\n",
879 			error);
880 		return error;
881 	}
882 
883 	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
884 	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
885 
886 	for (page = 0; page < n_fw_pages; page++) {
887 		error = elants_i2c_fw_write_page(client,
888 					fw->data + page * ELAN_FW_PAGESIZE);
889 		if (error) {
890 			dev_err(&client->dev,
891 				"failed to write FW page %d: %d\n",
892 				page, error);
893 			return error;
894 		}
895 	}
896 
897 	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
898 	msleep(300);
899 
900 	dev_info(&client->dev, "firmware update completed\n");
901 	return 0;
902 }
903 
904 static int elants_i2c_fw_update(struct elants_data *ts)
905 {
906 	struct i2c_client *client = ts->client;
907 	int error;
908 
909 	const char *fw_name __free(kfree) =
910 		kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
911 	if (!fw_name)
912 		return -ENOMEM;
913 
914 	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
915 
916 	const struct firmware *fw __free(firmware) = NULL;
917 	error = request_firmware(&fw, fw_name, &client->dev);
918 	if (error) {
919 		dev_err(&client->dev, "failed to request firmware: %d\n",
920 			error);
921 		return error;
922 	}
923 
924 	if (fw->size % ELAN_FW_PAGESIZE) {
925 		dev_err(&client->dev, "invalid firmware length: %zu\n",
926 			fw->size);
927 		return -EINVAL;
928 	}
929 
930 	scoped_guard(disable_irq, &client->irq) {
931 		bool force_update = ts->iap_mode == ELAN_IAP_RECOVERY;
932 
933 		error = elants_i2c_do_update_firmware(client, fw, force_update);
934 		if (error) {
935 			dev_err(&client->dev, "firmware update failed: %d\n",
936 				error);
937 		} else {
938 			error = elants_i2c_initialize(ts);
939 			if (error)
940 				dev_err(&client->dev,
941 					"failed to initialize device after firmware update: %d\n",
942 					error);
943 		}
944 
945 		ts->iap_mode = error ? ELAN_IAP_RECOVERY : ELAN_IAP_OPERATIONAL;
946 		ts->state = ELAN_STATE_NORMAL;
947 	}
948 	msleep(100);
949 
950 	if (!error)
951 		elants_i2c_calibrate(ts);
952 
953 	return error;
954 }
955 
956 /*
957  * Event reporting.
958  */
959 
960 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf,
961 				size_t packet_size)
962 {
963 	struct input_dev *input = ts->input;
964 	unsigned int n_fingers;
965 	unsigned int tool_type;
966 	u16 finger_state;
967 	int i;
968 
969 	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
970 	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
971 			buf[FW_POS_STATE];
972 
973 	dev_dbg(&ts->client->dev,
974 		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
975 
976 	/* Note: all fingers have the same tool type */
977 	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
978 			MT_TOOL_FINGER : MT_TOOL_PALM;
979 
980 	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
981 		if (finger_state & 1) {
982 			unsigned int x, y, p, w;
983 			u8 *pos;
984 
985 			pos = &buf[FW_POS_XY + i * 3];
986 			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
987 			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
988 
989 			/*
990 			 * eKTF3624 may have use "old" touch-report format,
991 			 * depending on a device and TS firmware version.
992 			 * For example, ASUS Transformer devices use the "old"
993 			 * format, while ASUS Nexus 7 uses the "new" formant.
994 			 */
995 			if (packet_size == PACKET_SIZE_OLD &&
996 			    ts->chip_id == EKTF3624) {
997 				w = buf[FW_POS_WIDTH + i / 2];
998 				w >>= 4 * (~i & 1);
999 				w |= w << 4;
1000 				w |= !w;
1001 				p = w;
1002 			} else {
1003 				p = buf[FW_POS_PRESSURE + i];
1004 				w = buf[FW_POS_WIDTH + i];
1005 			}
1006 
1007 			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
1008 				i, x, y, p, w);
1009 
1010 			input_mt_slot(input, i);
1011 			input_mt_report_slot_state(input, tool_type, true);
1012 			touchscreen_report_pos(input, &ts->prop, x, y, true);
1013 			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
1014 			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
1015 
1016 			n_fingers--;
1017 		}
1018 
1019 		finger_state >>= 1;
1020 	}
1021 
1022 	input_mt_sync_frame(input);
1023 	input_sync(input);
1024 }
1025 
1026 static u8 elants_i2c_calculate_checksum(u8 *buf)
1027 {
1028 	u8 checksum = 0;
1029 	u8 i;
1030 
1031 	for (i = 0; i < FW_POS_CHECKSUM; i++)
1032 		checksum += buf[i];
1033 
1034 	return checksum;
1035 }
1036 
1037 static void elants_i2c_event(struct elants_data *ts, u8 *buf,
1038 			     size_t packet_size)
1039 {
1040 	u8 checksum = elants_i2c_calculate_checksum(buf);
1041 
1042 	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
1043 		dev_warn(&ts->client->dev,
1044 			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
1045 			 __func__, buf[FW_POS_HEADER],
1046 			 checksum, buf[FW_POS_CHECKSUM]);
1047 	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
1048 		dev_warn(&ts->client->dev,
1049 			 "%s: unknown packet type: %02x\n",
1050 			 __func__, buf[FW_POS_HEADER]);
1051 	else
1052 		elants_i2c_mt_event(ts, buf, packet_size);
1053 }
1054 
1055 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
1056 {
1057 	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
1058 	struct elants_data *ts = _dev;
1059 	struct i2c_client *client = ts->client;
1060 	int report_count, report_len;
1061 	int i;
1062 	int len;
1063 
1064 	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
1065 	if (len < 0) {
1066 		dev_err(&client->dev, "%s: failed to read data: %d\n",
1067 			__func__, len);
1068 		goto out;
1069 	}
1070 
1071 	dev_dbg(&client->dev, "%s: packet %*ph\n",
1072 		__func__, HEADER_SIZE, ts->buf);
1073 
1074 	switch (ts->state) {
1075 	case ELAN_WAIT_RECALIBRATION:
1076 		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
1077 			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
1078 			complete(&ts->cmd_done);
1079 			ts->state = ELAN_STATE_NORMAL;
1080 		}
1081 		break;
1082 
1083 	case ELAN_WAIT_QUEUE_HEADER:
1084 		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
1085 			break;
1086 
1087 		ts->state = ELAN_STATE_NORMAL;
1088 		fallthrough;
1089 
1090 	case ELAN_STATE_NORMAL:
1091 
1092 		switch (ts->buf[FW_HDR_TYPE]) {
1093 		case CMD_HEADER_HELLO:
1094 		case CMD_HEADER_RESP:
1095 			break;
1096 
1097 		case QUEUE_HEADER_WAIT:
1098 			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
1099 				dev_err(&client->dev,
1100 					"invalid wait packet %*ph\n",
1101 					HEADER_SIZE, ts->buf);
1102 			} else {
1103 				ts->state = ELAN_WAIT_QUEUE_HEADER;
1104 				udelay(30);
1105 			}
1106 			break;
1107 
1108 		case QUEUE_HEADER_SINGLE:
1109 			elants_i2c_event(ts, &ts->buf[HEADER_SIZE],
1110 					 ts->buf[FW_HDR_LENGTH]);
1111 			break;
1112 
1113 		case QUEUE_HEADER_NORMAL2: /* CMD_HEADER_REK */
1114 			/*
1115 			 * Depending on firmware version, eKTF3624 touchscreens
1116 			 * may utilize one of these opcodes for the touch events:
1117 			 * 0x63 (NORMAL) and 0x66 (NORMAL2).  The 0x63 is used by
1118 			 * older firmware version and differs from 0x66 such that
1119 			 * touch pressure value needs to be adjusted.  The 0x66
1120 			 * opcode of newer firmware is equal to 0x63 of eKTH3500.
1121 			 */
1122 			if (ts->chip_id != EKTF3624)
1123 				break;
1124 
1125 			fallthrough;
1126 
1127 		case QUEUE_HEADER_NORMAL:
1128 			report_count = ts->buf[FW_HDR_COUNT];
1129 			if (report_count == 0 || report_count > 3) {
1130 				dev_err(&client->dev,
1131 					"bad report count: %*ph\n",
1132 					HEADER_SIZE, ts->buf);
1133 				break;
1134 			}
1135 
1136 			report_len = ts->buf[FW_HDR_LENGTH] / report_count;
1137 
1138 			if (report_len == PACKET_SIZE_OLD &&
1139 			    ts->chip_id == EKTF3624) {
1140 				dev_dbg_once(&client->dev,
1141 					     "using old report format\n");
1142 			} else if (report_len != PACKET_SIZE) {
1143 				dev_err(&client->dev,
1144 					"mismatching report length: %*ph\n",
1145 					HEADER_SIZE, ts->buf);
1146 				break;
1147 			}
1148 
1149 			for (i = 0; i < report_count; i++) {
1150 				u8 *buf = ts->buf + HEADER_SIZE +
1151 							i * report_len;
1152 				elants_i2c_event(ts, buf, report_len);
1153 			}
1154 			break;
1155 
1156 		default:
1157 			dev_err(&client->dev, "unknown packet %*ph\n",
1158 				HEADER_SIZE, ts->buf);
1159 			break;
1160 		}
1161 		break;
1162 	}
1163 
1164 out:
1165 	return IRQ_HANDLED;
1166 }
1167 
1168 /*
1169  * sysfs interface
1170  */
1171 static ssize_t calibrate_store(struct device *dev,
1172 			       struct device_attribute *attr,
1173 			       const char *buf, size_t count)
1174 {
1175 	struct i2c_client *client = to_i2c_client(dev);
1176 	struct elants_data *ts = i2c_get_clientdata(client);
1177 	int error;
1178 
1179 	scoped_cond_guard(mutex_intr, return -EINTR, &ts->sysfs_mutex) {
1180 		error = elants_i2c_calibrate(ts);
1181 		if (error)
1182 			return error;
1183 	}
1184 
1185 	return count;
1186 }
1187 
1188 static ssize_t write_update_fw(struct device *dev,
1189 			       struct device_attribute *attr,
1190 			       const char *buf, size_t count)
1191 {
1192 	struct i2c_client *client = to_i2c_client(dev);
1193 	struct elants_data *ts = i2c_get_clientdata(client);
1194 	int error;
1195 
1196 	scoped_cond_guard(mutex_intr, return -EINTR, &ts->sysfs_mutex) {
1197 		error = elants_i2c_fw_update(ts);
1198 		if (error)
1199 			return error;
1200 	}
1201 
1202 	return count;
1203 }
1204 
1205 static ssize_t show_iap_mode(struct device *dev,
1206 			     struct device_attribute *attr, char *buf)
1207 {
1208 	struct i2c_client *client = to_i2c_client(dev);
1209 	struct elants_data *ts = i2c_get_clientdata(client);
1210 
1211 	return sprintf(buf, "%s\n",
1212 		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
1213 				"Normal" : "Recovery");
1214 }
1215 
1216 static ssize_t show_calibration_count(struct device *dev,
1217 				      struct device_attribute *attr, char *buf)
1218 {
1219 	struct i2c_client *client = to_i2c_client(dev);
1220 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
1221 	u8 resp[HEADER_SIZE];
1222 	u16 rek_count;
1223 	int error;
1224 
1225 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
1226 					   resp, sizeof(resp), 1,
1227 					   "read ReK status");
1228 	if (error)
1229 		return sprintf(buf, "%d\n", error);
1230 
1231 	rek_count = get_unaligned_be16(&resp[2]);
1232 	return sprintf(buf, "0x%04x\n", rek_count);
1233 }
1234 
1235 static DEVICE_ATTR_WO(calibrate);
1236 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1237 static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
1238 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1239 
1240 struct elants_version_attribute {
1241 	struct device_attribute dattr;
1242 	size_t field_offset;
1243 	size_t field_size;
1244 };
1245 
1246 #define __ELANTS_FIELD_SIZE(_field)					\
1247 	sizeof(((struct elants_data *)NULL)->_field)
1248 #define __ELANTS_VERIFY_SIZE(_field)					\
1249 	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
1250 	 __ELANTS_FIELD_SIZE(_field))
1251 #define ELANTS_VERSION_ATTR(_field)					\
1252 	struct elants_version_attribute elants_ver_attr_##_field = {	\
1253 		.dattr = __ATTR(_field, S_IRUGO,			\
1254 				elants_version_attribute_show, NULL),	\
1255 		.field_offset = offsetof(struct elants_data, _field),	\
1256 		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
1257 	}
1258 
1259 static ssize_t elants_version_attribute_show(struct device *dev,
1260 					     struct device_attribute *dattr,
1261 					     char *buf)
1262 {
1263 	struct i2c_client *client = to_i2c_client(dev);
1264 	struct elants_data *ts = i2c_get_clientdata(client);
1265 	struct elants_version_attribute *attr =
1266 		container_of(dattr, struct elants_version_attribute, dattr);
1267 	u8 *field = (u8 *)((char *)ts + attr->field_offset);
1268 	unsigned int fmt_size;
1269 	unsigned int val;
1270 
1271 	if (attr->field_size == 1) {
1272 		val = *field;
1273 		fmt_size = 2; /* 2 HEX digits */
1274 	} else {
1275 		val = *(u16 *)field;
1276 		fmt_size = 4; /* 4 HEX digits */
1277 	}
1278 
1279 	return sprintf(buf, "%0*x\n", fmt_size, val);
1280 }
1281 
1282 static ELANTS_VERSION_ATTR(fw_version);
1283 static ELANTS_VERSION_ATTR(hw_version);
1284 static ELANTS_VERSION_ATTR(test_version);
1285 static ELANTS_VERSION_ATTR(solution_version);
1286 static ELANTS_VERSION_ATTR(bc_version);
1287 static ELANTS_VERSION_ATTR(iap_version);
1288 
1289 static struct attribute *elants_i2c_attrs[] = {
1290 	&dev_attr_calibrate.attr,
1291 	&dev_attr_update_fw.attr,
1292 	&dev_attr_iap_mode.attr,
1293 	&dev_attr_calibration_count.attr,
1294 
1295 	&elants_ver_attr_fw_version.dattr.attr,
1296 	&elants_ver_attr_hw_version.dattr.attr,
1297 	&elants_ver_attr_test_version.dattr.attr,
1298 	&elants_ver_attr_solution_version.dattr.attr,
1299 	&elants_ver_attr_bc_version.dattr.attr,
1300 	&elants_ver_attr_iap_version.dattr.attr,
1301 	NULL
1302 };
1303 ATTRIBUTE_GROUPS(elants_i2c);
1304 
1305 static int elants_i2c_power_on(struct elants_data *ts)
1306 {
1307 	int error;
1308 
1309 	/*
1310 	 * If we do not have reset gpio assume platform firmware
1311 	 * controls regulators and does power them on for us.
1312 	 */
1313 	if (IS_ERR_OR_NULL(ts->reset_gpio))
1314 		return 0;
1315 
1316 	error = regulator_enable(ts->vcc33);
1317 	if (error) {
1318 		dev_err(&ts->client->dev,
1319 			"failed to enable vcc33 regulator: %d\n",
1320 			error);
1321 		return error;
1322 	}
1323 
1324 	error = regulator_enable(ts->vccio);
1325 	if (error) {
1326 		dev_err(&ts->client->dev,
1327 			"failed to enable vccio regulator: %d\n",
1328 			error);
1329 		regulator_disable(ts->vcc33);
1330 		return error;
1331 	}
1332 
1333 	/*
1334 	 * We need to wait a bit after powering on controller before
1335 	 * we are allowed to release reset GPIO.
1336 	 */
1337 	usleep_range(ELAN_POWERON_DELAY_USEC, ELAN_POWERON_DELAY_USEC + 100);
1338 
1339 	gpiod_set_value_cansleep(ts->reset_gpio, 0);
1340 
1341 	msleep(ELAN_RESET_DELAY_MSEC);
1342 
1343 	return 0;
1344 }
1345 
1346 static void elants_i2c_power_off(void *_data)
1347 {
1348 	struct elants_data *ts = _data;
1349 
1350 	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1351 		/*
1352 		 * Activate reset gpio to prevent leakage through the
1353 		 * pin once we shut off power to the controller.
1354 		 */
1355 		gpiod_set_value_cansleep(ts->reset_gpio, 1);
1356 		regulator_disable(ts->vccio);
1357 		regulator_disable(ts->vcc33);
1358 	}
1359 }
1360 
1361 #ifdef CONFIG_ACPI
1362 static const struct acpi_device_id i2c_hid_ids[] = {
1363 	{"ACPI0C50", 0 },
1364 	{"PNP0C50", 0 },
1365 	{ },
1366 };
1367 
1368 static const guid_t i2c_hid_guid =
1369 	GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
1370 		  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
1371 
1372 static bool elants_acpi_is_hid_device(struct device *dev)
1373 {
1374 	acpi_handle handle = ACPI_HANDLE(dev);
1375 	union acpi_object *obj;
1376 
1377 	if (acpi_match_device_ids(ACPI_COMPANION(dev), i2c_hid_ids))
1378 		return false;
1379 
1380 	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, ACPI_TYPE_INTEGER);
1381 	if (obj) {
1382 		ACPI_FREE(obj);
1383 		return true;
1384 	}
1385 
1386 	return false;
1387 }
1388 #else
1389 static bool elants_acpi_is_hid_device(struct device *dev)
1390 {
1391 	return false;
1392 }
1393 #endif
1394 
1395 static int elants_i2c_probe(struct i2c_client *client)
1396 {
1397 	union i2c_smbus_data dummy;
1398 	struct elants_data *ts;
1399 	unsigned long irqflags;
1400 	int error;
1401 
1402 	/* Don't bind to i2c-hid compatible devices, these are handled by the i2c-hid drv. */
1403 	if (elants_acpi_is_hid_device(&client->dev)) {
1404 		dev_warn(&client->dev, "This device appears to be an I2C-HID device, not binding\n");
1405 		return -ENODEV;
1406 	}
1407 
1408 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1409 		dev_err(&client->dev, "I2C check functionality error\n");
1410 		return -ENXIO;
1411 	}
1412 
1413 	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1414 	if (!ts)
1415 		return -ENOMEM;
1416 
1417 	mutex_init(&ts->sysfs_mutex);
1418 	init_completion(&ts->cmd_done);
1419 
1420 	ts->client = client;
1421 	ts->chip_id = (enum elants_chip_id)(uintptr_t)device_get_match_data(&client->dev);
1422 	i2c_set_clientdata(client, ts);
1423 
1424 	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1425 	if (IS_ERR(ts->vcc33))
1426 		return dev_err_probe(&client->dev, PTR_ERR(ts->vcc33),
1427 				     "Failed to get 'vcc33' regulator\n");
1428 
1429 	ts->vccio = devm_regulator_get(&client->dev, "vccio");
1430 	if (IS_ERR(ts->vccio))
1431 		return dev_err_probe(&client->dev, PTR_ERR(ts->vccio),
1432 				     "Failed to get 'vccio' regulator\n");
1433 
1434 	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
1435 	if (IS_ERR(ts->reset_gpio)) {
1436 		error = PTR_ERR(ts->reset_gpio);
1437 
1438 		if (error == -EPROBE_DEFER)
1439 			return error;
1440 
1441 		if (error != -ENOENT && error != -ENOSYS) {
1442 			dev_err(&client->dev,
1443 				"failed to get reset gpio: %d\n",
1444 				error);
1445 			return error;
1446 		}
1447 
1448 		ts->keep_power_in_suspend = true;
1449 	}
1450 
1451 	error = elants_i2c_power_on(ts);
1452 	if (error)
1453 		return error;
1454 
1455 	error = devm_add_action_or_reset(&client->dev,
1456 					 elants_i2c_power_off, ts);
1457 	if (error) {
1458 		dev_err(&client->dev,
1459 			"failed to install power off action: %d\n", error);
1460 		return error;
1461 	}
1462 
1463 	/* Make sure there is something at this address */
1464 	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1465 			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1466 		dev_err(&client->dev, "nothing at this address\n");
1467 		return -ENXIO;
1468 	}
1469 
1470 	error = elants_i2c_initialize(ts);
1471 	if (error) {
1472 		dev_err(&client->dev, "failed to initialize: %d\n", error);
1473 		return error;
1474 	}
1475 
1476 	ts->input = devm_input_allocate_device(&client->dev);
1477 	if (!ts->input) {
1478 		dev_err(&client->dev, "Failed to allocate input device\n");
1479 		return -ENOMEM;
1480 	}
1481 
1482 	ts->input->name = "Elan Touchscreen";
1483 	ts->input->id.bustype = BUS_I2C;
1484 
1485 	/* Multitouch input params setup */
1486 
1487 	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1488 	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1489 	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1490 	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1491 	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
1492 			     0, MT_TOOL_PALM, 0, 0);
1493 
1494 	touchscreen_parse_properties(ts->input, true, &ts->prop);
1495 
1496 	if (ts->chip_id == EKTF3624 && ts->phy_x && ts->phy_y) {
1497 		/* calculate resolution from size */
1498 		ts->x_res = DIV_ROUND_CLOSEST(ts->prop.max_x, ts->phy_x);
1499 		ts->y_res = DIV_ROUND_CLOSEST(ts->prop.max_y, ts->phy_y);
1500 	}
1501 
1502 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1503 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1504 	input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->major_res);
1505 
1506 	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1507 				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1508 	if (error) {
1509 		dev_err(&client->dev,
1510 			"failed to initialize MT slots: %d\n", error);
1511 		return error;
1512 	}
1513 
1514 	error = input_register_device(ts->input);
1515 	if (error) {
1516 		dev_err(&client->dev,
1517 			"unable to register input device: %d\n", error);
1518 		return error;
1519 	}
1520 
1521 	/*
1522 	 * Platform code (ACPI, DTS) should normally set up interrupt
1523 	 * for us, but in case it did not let's fall back to using falling
1524 	 * edge to be compatible with older Chromebooks.
1525 	 */
1526 	irqflags = irq_get_trigger_type(client->irq);
1527 	if (!irqflags)
1528 		irqflags = IRQF_TRIGGER_FALLING;
1529 
1530 	error = devm_request_threaded_irq(&client->dev, client->irq,
1531 					  NULL, elants_i2c_irq,
1532 					  irqflags | IRQF_ONESHOT,
1533 					  client->name, ts);
1534 	if (error) {
1535 		dev_err(&client->dev, "Failed to register interrupt\n");
1536 		return error;
1537 	}
1538 
1539 	return 0;
1540 }
1541 
1542 static int elants_i2c_suspend(struct device *dev)
1543 {
1544 	struct i2c_client *client = to_i2c_client(dev);
1545 	struct elants_data *ts = i2c_get_clientdata(client);
1546 	const u8 set_sleep_cmd[] = {
1547 		CMD_HEADER_WRITE, E_POWER_STATE_SLEEP, 0x00, 0x01
1548 	};
1549 	int retry_cnt;
1550 	int error;
1551 
1552 	/* Command not support in IAP recovery mode */
1553 	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1554 		return -EBUSY;
1555 
1556 	disable_irq(client->irq);
1557 
1558 	if (device_may_wakeup(dev)) {
1559 		/*
1560 		 * The device will automatically enter idle mode
1561 		 * that has reduced power consumption.
1562 		 */
1563 		return 0;
1564 	} else if (ts->keep_power_in_suspend) {
1565 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1566 			error = elants_i2c_send(client, set_sleep_cmd,
1567 						sizeof(set_sleep_cmd));
1568 			if (!error)
1569 				break;
1570 
1571 			dev_err(&client->dev,
1572 				"suspend command failed: %d\n", error);
1573 		}
1574 	} else {
1575 		elants_i2c_power_off(ts);
1576 	}
1577 
1578 	return 0;
1579 }
1580 
1581 static int elants_i2c_resume(struct device *dev)
1582 {
1583 	struct i2c_client *client = to_i2c_client(dev);
1584 	struct elants_data *ts = i2c_get_clientdata(client);
1585 	const u8 set_active_cmd[] = {
1586 		CMD_HEADER_WRITE, E_POWER_STATE_RESUME, 0x00, 0x01
1587 	};
1588 	int retry_cnt;
1589 	int error;
1590 
1591 	if (device_may_wakeup(dev)) {
1592 		elants_i2c_sw_reset(client);
1593 	} else if (ts->keep_power_in_suspend) {
1594 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1595 			error = elants_i2c_send(client, set_active_cmd,
1596 						sizeof(set_active_cmd));
1597 			if (!error)
1598 				break;
1599 
1600 			dev_err(&client->dev,
1601 				"resume command failed: %d\n", error);
1602 		}
1603 	} else {
1604 		elants_i2c_power_on(ts);
1605 		elants_i2c_initialize(ts);
1606 	}
1607 
1608 	ts->state = ELAN_STATE_NORMAL;
1609 	enable_irq(client->irq);
1610 
1611 	return 0;
1612 }
1613 
1614 static DEFINE_SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1615 				elants_i2c_suspend, elants_i2c_resume);
1616 
1617 static const struct i2c_device_id elants_i2c_id[] = {
1618 	{ DEVICE_NAME, EKTH3500 },
1619 	{ "ekth3500", EKTH3500 },
1620 	{ "ektf3624", EKTF3624 },
1621 	{ }
1622 };
1623 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1624 
1625 #ifdef CONFIG_ACPI
1626 static const struct acpi_device_id elants_acpi_id[] = {
1627 	{ "ELAN0001", EKTH3500 },
1628 	{ }
1629 };
1630 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1631 #endif
1632 
1633 #ifdef CONFIG_OF
1634 static const struct of_device_id elants_of_match[] = {
1635 	{ .compatible = "elan,ekth3500", .data = (void *)EKTH3500 },
1636 	{ .compatible = "elan,ektf3624", .data = (void *)EKTF3624 },
1637 	{ /* sentinel */ }
1638 };
1639 MODULE_DEVICE_TABLE(of, elants_of_match);
1640 #endif
1641 
1642 static struct i2c_driver elants_i2c_driver = {
1643 	.probe = elants_i2c_probe,
1644 	.id_table = elants_i2c_id,
1645 	.driver = {
1646 		.name = DEVICE_NAME,
1647 		.dev_groups = elants_i2c_groups,
1648 		.pm = pm_sleep_ptr(&elants_i2c_pm_ops),
1649 		.acpi_match_table = ACPI_PTR(elants_acpi_id),
1650 		.of_match_table = of_match_ptr(elants_of_match),
1651 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1652 	},
1653 };
1654 module_i2c_driver(elants_i2c_driver);
1655 
1656 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1657 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1658 MODULE_LICENSE("GPL");
1659