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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 <linux/uuid.h>
42 #include <asm/unaligned.h>
43 
44 /* Device, Driver information */
45 #define DEVICE_NAME	"elants_i2c"
46 
47 /* Convert from rows or columns into resolution */
48 #define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
49 
50 /* FW header data */
51 #define HEADER_SIZE		4
52 #define FW_HDR_TYPE		0
53 #define FW_HDR_COUNT		1
54 #define FW_HDR_LENGTH		2
55 
56 /* Buffer mode Queue Header information */
57 #define QUEUE_HEADER_SINGLE	0x62
58 #define QUEUE_HEADER_NORMAL	0X63
59 #define QUEUE_HEADER_WAIT	0x64
60 
61 /* Command header definition */
62 #define CMD_HEADER_WRITE	0x54
63 #define CMD_HEADER_READ		0x53
64 #define CMD_HEADER_6B_READ	0x5B
65 #define CMD_HEADER_ROM_READ	0x96
66 #define CMD_HEADER_RESP		0x52
67 #define CMD_HEADER_6B_RESP	0x9B
68 #define CMD_HEADER_ROM_RESP	0x95
69 #define CMD_HEADER_HELLO	0x55
70 #define CMD_HEADER_REK		0x66
71 
72 /* FW position data */
73 #define PACKET_SIZE		55
74 #define MAX_CONTACT_NUM		10
75 #define FW_POS_HEADER		0
76 #define FW_POS_STATE		1
77 #define FW_POS_TOTAL		2
78 #define FW_POS_XY		3
79 #define FW_POS_TOOL_TYPE	33
80 #define FW_POS_CHECKSUM		34
81 #define FW_POS_WIDTH		35
82 #define FW_POS_PRESSURE		45
83 
84 #define HEADER_REPORT_10_FINGER	0x62
85 
86 /* Header (4 bytes) plus 3 fill 10-finger packets */
87 #define MAX_PACKET_SIZE		169
88 
89 #define BOOT_TIME_DELAY_MS	50
90 
91 /* FW read command, 0x53 0x?? 0x0, 0x01 */
92 #define E_ELAN_INFO_FW_VER	0x00
93 #define E_ELAN_INFO_BC_VER	0x10
94 #define E_ELAN_INFO_REK		0xD0
95 #define E_ELAN_INFO_TEST_VER	0xE0
96 #define E_ELAN_INFO_FW_ID	0xF0
97 #define E_INFO_OSR		0xD6
98 #define E_INFO_PHY_SCAN		0xD7
99 #define E_INFO_PHY_DRIVER	0xD8
100 
101 #define MAX_RETRIES		3
102 #define MAX_FW_UPDATE_RETRIES	30
103 
104 #define ELAN_FW_PAGESIZE	132
105 
106 /* calibration timeout definition */
107 #define ELAN_CALI_TIMEOUT_MSEC	12000
108 
109 #define ELAN_POWERON_DELAY_USEC	500
110 #define ELAN_RESET_DELAY_MSEC	20
111 
112 /* FW boot code version */
113 #define BC_VER_H_BYTE_FOR_EKTH3900x1_I2C        0x72
114 #define BC_VER_H_BYTE_FOR_EKTH3900x2_I2C        0x82
115 #define BC_VER_H_BYTE_FOR_EKTH3900x3_I2C        0x92
116 #define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C        0x6D
117 #define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C        0x6E
118 #define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C       0x77
119 #define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C       0x78
120 #define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB    0x67
121 #define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB    0x68
122 #define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB   0x74
123 #define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB   0x75
124 
125 enum elants_state {
126 	ELAN_STATE_NORMAL,
127 	ELAN_WAIT_QUEUE_HEADER,
128 	ELAN_WAIT_RECALIBRATION,
129 };
130 
131 enum elants_iap_mode {
132 	ELAN_IAP_OPERATIONAL,
133 	ELAN_IAP_RECOVERY,
134 };
135 
136 /* struct elants_data - represents state of Elan touchscreen device */
137 struct elants_data {
138 	struct i2c_client *client;
139 	struct input_dev *input;
140 
141 	struct regulator *vcc33;
142 	struct regulator *vccio;
143 	struct gpio_desc *reset_gpio;
144 
145 	u16 fw_version;
146 	u8 test_version;
147 	u8 solution_version;
148 	u8 bc_version;
149 	u8 iap_version;
150 	u16 hw_version;
151 	u8 major_res;
152 	unsigned int x_res;	/* resolution in units/mm */
153 	unsigned int y_res;
154 	unsigned int x_max;
155 	unsigned int y_max;
156 	struct touchscreen_properties prop;
157 
158 	enum elants_state state;
159 	enum elants_iap_mode iap_mode;
160 
161 	/* Guards against concurrent access to the device via sysfs */
162 	struct mutex sysfs_mutex;
163 
164 	u8 cmd_resp[HEADER_SIZE];
165 	struct completion cmd_done;
166 
167 	bool wake_irq_enabled;
168 	bool keep_power_in_suspend;
169 
170 	/* Must be last to be used for DMA operations */
171 	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
172 };
173 
elants_i2c_send(struct i2c_client * client,const void * data,size_t size)174 static int elants_i2c_send(struct i2c_client *client,
175 			   const void *data, size_t size)
176 {
177 	int ret;
178 
179 	ret = i2c_master_send(client, data, size);
180 	if (ret == size)
181 		return 0;
182 
183 	if (ret >= 0)
184 		ret = -EIO;
185 
186 	dev_err(&client->dev, "%s failed (%*ph): %d\n",
187 		__func__, (int)size, data, ret);
188 
189 	return ret;
190 }
191 
elants_i2c_read(struct i2c_client * client,void * data,size_t size)192 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
193 {
194 	int ret;
195 
196 	ret = i2c_master_recv(client, data, size);
197 	if (ret == size)
198 		return 0;
199 
200 	if (ret >= 0)
201 		ret = -EIO;
202 
203 	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
204 
205 	return ret;
206 }
207 
elants_i2c_execute_command(struct i2c_client * client,const u8 * cmd,size_t cmd_size,u8 * resp,size_t resp_size,int retries,const char * cmd_name)208 static int elants_i2c_execute_command(struct i2c_client *client,
209 				      const u8 *cmd, size_t cmd_size,
210 				      u8 *resp, size_t resp_size,
211 				      int retries, const char *cmd_name)
212 {
213 	struct i2c_msg msgs[2];
214 	int ret;
215 	u8 expected_response;
216 
217 	switch (cmd[0]) {
218 	case CMD_HEADER_READ:
219 		expected_response = CMD_HEADER_RESP;
220 		break;
221 
222 	case CMD_HEADER_6B_READ:
223 		expected_response = CMD_HEADER_6B_RESP;
224 		break;
225 
226 	case CMD_HEADER_ROM_READ:
227 		expected_response = CMD_HEADER_ROM_RESP;
228 		break;
229 
230 	default:
231 		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
232 			cmd_name, (int)cmd_size, cmd);
233 		return -EINVAL;
234 	}
235 
236 	for (;;) {
237 		msgs[0].addr = client->addr;
238 		msgs[0].flags = client->flags & I2C_M_TEN;
239 		msgs[0].len = cmd_size;
240 		msgs[0].buf = (u8 *)cmd;
241 
242 		msgs[1].addr = client->addr;
243 		msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
244 		msgs[1].flags |= I2C_M_RD;
245 		msgs[1].len = resp_size;
246 		msgs[1].buf = resp;
247 
248 		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
249 		if (ret < 0) {
250 			if (--retries > 0) {
251 				dev_dbg(&client->dev,
252 					"(%s) I2C transfer failed: %pe (retrying)\n",
253 					cmd_name, ERR_PTR(ret));
254 				continue;
255 			}
256 
257 			dev_err(&client->dev,
258 				"(%s) I2C transfer failed: %pe\n",
259 				cmd_name, ERR_PTR(ret));
260 			return ret;
261 		}
262 
263 		if (ret != ARRAY_SIZE(msgs) ||
264 		    resp[FW_HDR_TYPE] != expected_response) {
265 			if (--retries > 0) {
266 				dev_dbg(&client->dev,
267 					"(%s) unexpected response: %*ph (retrying)\n",
268 					cmd_name, ret, resp);
269 				continue;
270 			}
271 
272 			dev_err(&client->dev,
273 				"(%s) unexpected response: %*ph\n",
274 				cmd_name, ret, resp);
275 			return -EIO;
276 		}
277 
278 		return 0;
279 	}
280 }
281 
elants_i2c_calibrate(struct elants_data * ts)282 static int elants_i2c_calibrate(struct elants_data *ts)
283 {
284 	struct i2c_client *client = ts->client;
285 	int ret, error;
286 	static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
287 	static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
288 	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
289 
290 	disable_irq(client->irq);
291 
292 	ts->state = ELAN_WAIT_RECALIBRATION;
293 	reinit_completion(&ts->cmd_done);
294 
295 	elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
296 	elants_i2c_send(client, rek, sizeof(rek));
297 
298 	enable_irq(client->irq);
299 
300 	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
301 				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
302 
303 	ts->state = ELAN_STATE_NORMAL;
304 
305 	if (ret <= 0) {
306 		error = ret < 0 ? ret : -ETIMEDOUT;
307 		dev_err(&client->dev,
308 			"error while waiting for calibration to complete: %d\n",
309 			error);
310 		return error;
311 	}
312 
313 	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
314 		dev_err(&client->dev,
315 			"unexpected calibration response: %*ph\n",
316 			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
317 		return -EINVAL;
318 	}
319 
320 	return 0;
321 }
322 
elants_i2c_sw_reset(struct i2c_client * client)323 static int elants_i2c_sw_reset(struct i2c_client *client)
324 {
325 	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
326 	int error;
327 
328 	error = elants_i2c_send(client, soft_rst_cmd,
329 				sizeof(soft_rst_cmd));
330 	if (error) {
331 		dev_err(&client->dev, "software reset failed: %d\n", error);
332 		return error;
333 	}
334 
335 	/*
336 	 * We should wait at least 10 msec (but no more than 40) before
337 	 * sending fastboot or IAP command to the device.
338 	 */
339 	msleep(30);
340 
341 	return 0;
342 }
343 
elants_i2c_parse_version(u8 * buf)344 static u16 elants_i2c_parse_version(u8 *buf)
345 {
346 	return get_unaligned_be32(buf) >> 4;
347 }
348 
elants_i2c_query_hw_version(struct elants_data * ts)349 static int elants_i2c_query_hw_version(struct elants_data *ts)
350 {
351 	struct i2c_client *client = ts->client;
352 	int retry_cnt = MAX_RETRIES;
353 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
354 	u8 resp[HEADER_SIZE];
355 	int error;
356 
357 	while (retry_cnt--) {
358 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
359 						   resp, sizeof(resp), 1,
360 						   "read fw id");
361 		if (error)
362 			return error;
363 
364 		ts->hw_version = elants_i2c_parse_version(resp);
365 		if (ts->hw_version != 0xffff)
366 			return 0;
367 	}
368 
369 	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
370 
371 	return -EINVAL;
372 }
373 
elants_i2c_query_fw_version(struct elants_data * ts)374 static int elants_i2c_query_fw_version(struct elants_data *ts)
375 {
376 	struct i2c_client *client = ts->client;
377 	int retry_cnt = MAX_RETRIES;
378 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
379 	u8 resp[HEADER_SIZE];
380 	int error;
381 
382 	while (retry_cnt--) {
383 		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
384 						   resp, sizeof(resp), 1,
385 						   "read fw version");
386 		if (error)
387 			return error;
388 
389 		ts->fw_version = elants_i2c_parse_version(resp);
390 		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
391 			return 0;
392 
393 		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
394 			(int)sizeof(resp), resp);
395 	}
396 
397 	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
398 
399 	return -EINVAL;
400 }
401 
elants_i2c_query_test_version(struct elants_data * ts)402 static int elants_i2c_query_test_version(struct elants_data *ts)
403 {
404 	struct i2c_client *client = ts->client;
405 	int error;
406 	u16 version;
407 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
408 	u8 resp[HEADER_SIZE];
409 
410 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
411 					   resp, sizeof(resp), MAX_RETRIES,
412 					   "read test version");
413 	if (error) {
414 		dev_err(&client->dev, "Failed to read test version\n");
415 		return error;
416 	}
417 
418 	version = elants_i2c_parse_version(resp);
419 	ts->test_version = version >> 8;
420 	ts->solution_version = version & 0xff;
421 
422 	return 0;
423 }
424 
elants_i2c_query_bc_version(struct elants_data * ts)425 static int elants_i2c_query_bc_version(struct elants_data *ts)
426 {
427 	struct i2c_client *client = ts->client;
428 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
429 	u8 resp[HEADER_SIZE];
430 	u16 version;
431 	int error;
432 
433 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
434 					   resp, sizeof(resp), 1,
435 					   "read BC version");
436 	if (error)
437 		return error;
438 
439 	version = elants_i2c_parse_version(resp);
440 	ts->bc_version = version >> 8;
441 	ts->iap_version = version & 0xff;
442 
443 	return 0;
444 }
445 
elants_i2c_query_ts_info(struct elants_data * ts)446 static int elants_i2c_query_ts_info(struct elants_data *ts)
447 {
448 	struct i2c_client *client = ts->client;
449 	int error;
450 	u8 resp[17];
451 	u16 phy_x, phy_y, rows, cols, osr;
452 	const u8 get_resolution_cmd[] = {
453 		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
454 	};
455 	const u8 get_osr_cmd[] = {
456 		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
457 	};
458 	const u8 get_physical_scan_cmd[] = {
459 		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
460 	};
461 	const u8 get_physical_drive_cmd[] = {
462 		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
463 	};
464 
465 	/* Get trace number */
466 	error = elants_i2c_execute_command(client,
467 					   get_resolution_cmd,
468 					   sizeof(get_resolution_cmd),
469 					   resp, sizeof(resp), 1,
470 					   "get resolution");
471 	if (error)
472 		return error;
473 
474 	rows = resp[2] + resp[6] + resp[10];
475 	cols = resp[3] + resp[7] + resp[11];
476 
477 	/* Get report resolution value of ABS_MT_TOUCH_MAJOR */
478 	ts->major_res = resp[16];
479 
480 	/* Process mm_to_pixel information */
481 	error = elants_i2c_execute_command(client,
482 					   get_osr_cmd, sizeof(get_osr_cmd),
483 					   resp, sizeof(resp), 1, "get osr");
484 	if (error)
485 		return error;
486 
487 	osr = resp[3];
488 
489 	error = elants_i2c_execute_command(client,
490 					   get_physical_scan_cmd,
491 					   sizeof(get_physical_scan_cmd),
492 					   resp, sizeof(resp), 1,
493 					   "get physical scan");
494 	if (error)
495 		return error;
496 
497 	phy_x = get_unaligned_be16(&resp[2]);
498 
499 	error = elants_i2c_execute_command(client,
500 					   get_physical_drive_cmd,
501 					   sizeof(get_physical_drive_cmd),
502 					   resp, sizeof(resp), 1,
503 					   "get physical drive");
504 	if (error)
505 		return error;
506 
507 	phy_y = get_unaligned_be16(&resp[2]);
508 
509 	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
510 
511 	if (rows == 0 || cols == 0 || osr == 0) {
512 		dev_warn(&client->dev,
513 			 "invalid trace number data: %d, %d, %d\n",
514 			 rows, cols, osr);
515 	} else {
516 		/* translate trace number to TS resolution */
517 		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
518 		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
519 		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
520 		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
521 	}
522 
523 	return 0;
524 }
525 
elants_i2c_fastboot(struct i2c_client * client)526 static int elants_i2c_fastboot(struct i2c_client *client)
527 {
528 	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
529 	int error;
530 
531 	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
532 	if (error) {
533 		dev_err(&client->dev, "boot failed: %d\n", error);
534 		return error;
535 	}
536 
537 	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
538 	return 0;
539 }
540 
elants_i2c_initialize(struct elants_data * ts)541 static int elants_i2c_initialize(struct elants_data *ts)
542 {
543 	struct i2c_client *client = ts->client;
544 	int error, error2, retry_cnt;
545 	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
546 	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
547 	u8 buf[HEADER_SIZE];
548 
549 	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
550 		error = elants_i2c_sw_reset(client);
551 		if (error) {
552 			/* Continue initializing if it's the last try */
553 			if (retry_cnt < MAX_RETRIES - 1)
554 				continue;
555 		}
556 
557 		error = elants_i2c_fastboot(client);
558 		if (error) {
559 			/* Continue initializing if it's the last try */
560 			if (retry_cnt < MAX_RETRIES - 1)
561 				continue;
562 		}
563 
564 		/* Wait for Hello packet */
565 		msleep(BOOT_TIME_DELAY_MS);
566 
567 		error = elants_i2c_read(client, buf, sizeof(buf));
568 		if (error) {
569 			dev_err(&client->dev,
570 				"failed to read 'hello' packet: %d\n", error);
571 		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
572 			ts->iap_mode = ELAN_IAP_OPERATIONAL;
573 			break;
574 		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
575 			/*
576 			 * Setting error code will mark device
577 			 * in recovery mode below.
578 			 */
579 			error = -EIO;
580 			break;
581 		} else {
582 			error = -EINVAL;
583 			dev_err(&client->dev,
584 				"invalid 'hello' packet: %*ph\n",
585 				(int)sizeof(buf), buf);
586 		}
587 	}
588 
589 	/* hw version is available even if device in recovery state */
590 	error2 = elants_i2c_query_hw_version(ts);
591 	if (!error2)
592 		error2 = elants_i2c_query_bc_version(ts);
593 	if (!error)
594 		error = error2;
595 
596 	if (!error)
597 		error = elants_i2c_query_fw_version(ts);
598 	if (!error)
599 		error = elants_i2c_query_test_version(ts);
600 	if (!error)
601 		error = elants_i2c_query_ts_info(ts);
602 
603 	if (error)
604 		ts->iap_mode = ELAN_IAP_RECOVERY;
605 
606 	return 0;
607 }
608 
609 /*
610  * Firmware update interface.
611  */
612 
elants_i2c_fw_write_page(struct i2c_client * client,const void * page)613 static int elants_i2c_fw_write_page(struct i2c_client *client,
614 				    const void *page)
615 {
616 	const u8 ack_ok[] = { 0xaa, 0xaa };
617 	u8 buf[2];
618 	int retry;
619 	int error;
620 
621 	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
622 		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
623 		if (error) {
624 			dev_err(&client->dev,
625 				"IAP Write Page failed: %d\n", error);
626 			continue;
627 		}
628 
629 		error = elants_i2c_read(client, buf, 2);
630 		if (error) {
631 			dev_err(&client->dev,
632 				"IAP Ack read failed: %d\n", error);
633 			return error;
634 		}
635 
636 		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
637 			return 0;
638 
639 		error = -EIO;
640 		dev_err(&client->dev,
641 			"IAP Get Ack Error [%02x:%02x]\n",
642 			buf[0], buf[1]);
643 	}
644 
645 	return error;
646 }
647 
elants_i2c_validate_remark_id(struct elants_data * ts,const struct firmware * fw)648 static int elants_i2c_validate_remark_id(struct elants_data *ts,
649 					 const struct firmware *fw)
650 {
651 	struct i2c_client *client = ts->client;
652 	int error;
653 	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
654 	u8 resp[6] = { 0 };
655 	u16 ts_remark_id = 0;
656 	u16 fw_remark_id = 0;
657 
658 	/* Compare TS Remark ID and FW Remark ID */
659 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
660 					   resp, sizeof(resp),
661 					   1, "read Remark ID");
662 	if (error)
663 		return error;
664 
665 	ts_remark_id = get_unaligned_be16(&resp[3]);
666 
667 	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
668 
669 	if (fw_remark_id != ts_remark_id) {
670 		dev_err(&client->dev,
671 			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
672 			ts_remark_id, fw_remark_id);
673 		return -EINVAL;
674 	}
675 
676 	return 0;
677 }
678 
elants_i2c_should_check_remark_id(struct elants_data * ts)679 static bool elants_i2c_should_check_remark_id(struct elants_data *ts)
680 {
681 	struct i2c_client *client = ts->client;
682 	const u8 bootcode_version = ts->iap_version;
683 	bool check;
684 
685 	/* I2C eKTH3900 and eKTH5312 are NOT support Remark ID */
686 	if ((bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x1_I2C) ||
687 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x2_I2C) ||
688 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x3_I2C) ||
689 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C) ||
690 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C) ||
691 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C) ||
692 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C) ||
693 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB) ||
694 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB) ||
695 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB) ||
696 	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB)) {
697 		dev_dbg(&client->dev,
698 			"eKTH3900/eKTH5312(0x%02x) are not support remark id\n",
699 			bootcode_version);
700 		check = false;
701 	} else if (bootcode_version >= 0x60) {
702 		check = true;
703 	} else {
704 		check = false;
705 	}
706 
707 	return check;
708 }
709 
elants_i2c_do_update_firmware(struct i2c_client * client,const struct firmware * fw,bool force)710 static int elants_i2c_do_update_firmware(struct i2c_client *client,
711 					 const struct firmware *fw,
712 					 bool force)
713 {
714 	struct elants_data *ts = i2c_get_clientdata(client);
715 	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
716 	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
717 	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
718 	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
719 	u8 buf[HEADER_SIZE];
720 	u16 send_id;
721 	int page, n_fw_pages;
722 	int error;
723 	bool check_remark_id = elants_i2c_should_check_remark_id(ts);
724 
725 	/* Recovery mode detection! */
726 	if (force) {
727 		dev_dbg(&client->dev, "Recovery mode procedure\n");
728 
729 		if (check_remark_id) {
730 			error = elants_i2c_validate_remark_id(ts, fw);
731 			if (error)
732 				return error;
733 		}
734 
735 		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
736 		if (error) {
737 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
738 				error);
739 			return error;
740 		}
741 	} else {
742 		/* Start IAP Procedure */
743 		dev_dbg(&client->dev, "Normal IAP procedure\n");
744 
745 		/* Close idle mode */
746 		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
747 		if (error)
748 			dev_err(&client->dev, "Failed close idle: %d\n", error);
749 		msleep(60);
750 
751 		elants_i2c_sw_reset(client);
752 		msleep(20);
753 
754 		if (check_remark_id) {
755 			error = elants_i2c_validate_remark_id(ts, fw);
756 			if (error)
757 				return error;
758 		}
759 
760 		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
761 		if (error) {
762 			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
763 				error);
764 			return error;
765 		}
766 	}
767 
768 	msleep(20);
769 
770 	/* check IAP state */
771 	error = elants_i2c_read(client, buf, 4);
772 	if (error) {
773 		dev_err(&client->dev,
774 			"failed to read IAP acknowledgement: %d\n",
775 			error);
776 		return error;
777 	}
778 
779 	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
780 		dev_err(&client->dev,
781 			"failed to enter IAP: %*ph (expected %*ph)\n",
782 			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
783 		return -EIO;
784 	}
785 
786 	dev_info(&client->dev, "successfully entered IAP mode");
787 
788 	send_id = client->addr;
789 	error = elants_i2c_send(client, &send_id, 1);
790 	if (error) {
791 		dev_err(&client->dev, "sending dummy byte failed: %d\n",
792 			error);
793 		return error;
794 	}
795 
796 	/* Clear the last page of Master */
797 	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
798 	if (error) {
799 		dev_err(&client->dev, "clearing of the last page failed: %d\n",
800 			error);
801 		return error;
802 	}
803 
804 	error = elants_i2c_read(client, buf, 2);
805 	if (error) {
806 		dev_err(&client->dev,
807 			"failed to read ACK for clearing the last page: %d\n",
808 			error);
809 		return error;
810 	}
811 
812 	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
813 	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
814 
815 	for (page = 0; page < n_fw_pages; page++) {
816 		error = elants_i2c_fw_write_page(client,
817 					fw->data + page * ELAN_FW_PAGESIZE);
818 		if (error) {
819 			dev_err(&client->dev,
820 				"failed to write FW page %d: %d\n",
821 				page, error);
822 			return error;
823 		}
824 	}
825 
826 	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
827 	msleep(300);
828 
829 	dev_info(&client->dev, "firmware update completed\n");
830 	return 0;
831 }
832 
elants_i2c_fw_update(struct elants_data * ts)833 static int elants_i2c_fw_update(struct elants_data *ts)
834 {
835 	struct i2c_client *client = ts->client;
836 	const struct firmware *fw;
837 	char *fw_name;
838 	int error;
839 
840 	fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
841 	if (!fw_name)
842 		return -ENOMEM;
843 
844 	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
845 	error = request_firmware(&fw, fw_name, &client->dev);
846 	kfree(fw_name);
847 	if (error) {
848 		dev_err(&client->dev, "failed to request firmware: %d\n",
849 			error);
850 		return error;
851 	}
852 
853 	if (fw->size % ELAN_FW_PAGESIZE) {
854 		dev_err(&client->dev, "invalid firmware length: %zu\n",
855 			fw->size);
856 		error = -EINVAL;
857 		goto out;
858 	}
859 
860 	disable_irq(client->irq);
861 
862 	error = elants_i2c_do_update_firmware(client, fw,
863 					ts->iap_mode == ELAN_IAP_RECOVERY);
864 	if (error) {
865 		dev_err(&client->dev, "firmware update failed: %d\n", error);
866 		ts->iap_mode = ELAN_IAP_RECOVERY;
867 		goto out_enable_irq;
868 	}
869 
870 	error = elants_i2c_initialize(ts);
871 	if (error) {
872 		dev_err(&client->dev,
873 			"failed to initialize device after firmware update: %d\n",
874 			error);
875 		ts->iap_mode = ELAN_IAP_RECOVERY;
876 		goto out_enable_irq;
877 	}
878 
879 	ts->iap_mode = ELAN_IAP_OPERATIONAL;
880 
881 out_enable_irq:
882 	ts->state = ELAN_STATE_NORMAL;
883 	enable_irq(client->irq);
884 	msleep(100);
885 
886 	if (!error)
887 		elants_i2c_calibrate(ts);
888 out:
889 	release_firmware(fw);
890 	return error;
891 }
892 
893 /*
894  * Event reporting.
895  */
896 
elants_i2c_mt_event(struct elants_data * ts,u8 * buf)897 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
898 {
899 	struct input_dev *input = ts->input;
900 	unsigned int n_fingers;
901 	unsigned int tool_type;
902 	u16 finger_state;
903 	int i;
904 
905 	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
906 	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
907 			buf[FW_POS_STATE];
908 
909 	dev_dbg(&ts->client->dev,
910 		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
911 
912 	/* Note: all fingers have the same tool type */
913 	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
914 			MT_TOOL_FINGER : MT_TOOL_PALM;
915 
916 	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
917 		if (finger_state & 1) {
918 			unsigned int x, y, p, w;
919 			u8 *pos;
920 
921 			pos = &buf[FW_POS_XY + i * 3];
922 			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
923 			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
924 			p = buf[FW_POS_PRESSURE + i];
925 			w = buf[FW_POS_WIDTH + i];
926 
927 			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
928 				i, x, y, p, w);
929 
930 			input_mt_slot(input, i);
931 			input_mt_report_slot_state(input, tool_type, true);
932 			touchscreen_report_pos(input, &ts->prop, x, y, true);
933 			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
934 			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
935 
936 			n_fingers--;
937 		}
938 
939 		finger_state >>= 1;
940 	}
941 
942 	input_mt_sync_frame(input);
943 	input_sync(input);
944 }
945 
elants_i2c_calculate_checksum(u8 * buf)946 static u8 elants_i2c_calculate_checksum(u8 *buf)
947 {
948 	u8 checksum = 0;
949 	u8 i;
950 
951 	for (i = 0; i < FW_POS_CHECKSUM; i++)
952 		checksum += buf[i];
953 
954 	return checksum;
955 }
956 
elants_i2c_event(struct elants_data * ts,u8 * buf)957 static void elants_i2c_event(struct elants_data *ts, u8 *buf)
958 {
959 	u8 checksum = elants_i2c_calculate_checksum(buf);
960 
961 	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
962 		dev_warn(&ts->client->dev,
963 			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
964 			 __func__, buf[FW_POS_HEADER],
965 			 checksum, buf[FW_POS_CHECKSUM]);
966 	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
967 		dev_warn(&ts->client->dev,
968 			 "%s: unknown packet type: %02x\n",
969 			 __func__, buf[FW_POS_HEADER]);
970 	else
971 		elants_i2c_mt_event(ts, buf);
972 }
973 
elants_i2c_irq(int irq,void * _dev)974 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
975 {
976 	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
977 	struct elants_data *ts = _dev;
978 	struct i2c_client *client = ts->client;
979 	int report_count, report_len;
980 	int i;
981 	int len;
982 
983 	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
984 	if (len < 0) {
985 		dev_err(&client->dev, "%s: failed to read data: %d\n",
986 			__func__, len);
987 		goto out;
988 	}
989 
990 	dev_dbg(&client->dev, "%s: packet %*ph\n",
991 		__func__, HEADER_SIZE, ts->buf);
992 
993 	switch (ts->state) {
994 	case ELAN_WAIT_RECALIBRATION:
995 		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
996 			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
997 			complete(&ts->cmd_done);
998 			ts->state = ELAN_STATE_NORMAL;
999 		}
1000 		break;
1001 
1002 	case ELAN_WAIT_QUEUE_HEADER:
1003 		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
1004 			break;
1005 
1006 		ts->state = ELAN_STATE_NORMAL;
1007 		fallthrough;
1008 
1009 	case ELAN_STATE_NORMAL:
1010 
1011 		switch (ts->buf[FW_HDR_TYPE]) {
1012 		case CMD_HEADER_HELLO:
1013 		case CMD_HEADER_RESP:
1014 		case CMD_HEADER_REK:
1015 			break;
1016 
1017 		case QUEUE_HEADER_WAIT:
1018 			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
1019 				dev_err(&client->dev,
1020 					"invalid wait packet %*ph\n",
1021 					HEADER_SIZE, ts->buf);
1022 			} else {
1023 				ts->state = ELAN_WAIT_QUEUE_HEADER;
1024 				udelay(30);
1025 			}
1026 			break;
1027 
1028 		case QUEUE_HEADER_SINGLE:
1029 			elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
1030 			break;
1031 
1032 		case QUEUE_HEADER_NORMAL:
1033 			report_count = ts->buf[FW_HDR_COUNT];
1034 			if (report_count == 0 || report_count > 3) {
1035 				dev_err(&client->dev,
1036 					"bad report count: %*ph\n",
1037 					HEADER_SIZE, ts->buf);
1038 				break;
1039 			}
1040 
1041 			report_len = ts->buf[FW_HDR_LENGTH] / report_count;
1042 			if (report_len != PACKET_SIZE) {
1043 				dev_err(&client->dev,
1044 					"mismatching report length: %*ph\n",
1045 					HEADER_SIZE, ts->buf);
1046 				break;
1047 			}
1048 
1049 			for (i = 0; i < report_count; i++) {
1050 				u8 *buf = ts->buf + HEADER_SIZE +
1051 							i * PACKET_SIZE;
1052 				elants_i2c_event(ts, buf);
1053 			}
1054 			break;
1055 
1056 		default:
1057 			dev_err(&client->dev, "unknown packet %*ph\n",
1058 				HEADER_SIZE, ts->buf);
1059 			break;
1060 		}
1061 		break;
1062 	}
1063 
1064 out:
1065 	return IRQ_HANDLED;
1066 }
1067 
1068 /*
1069  * sysfs interface
1070  */
calibrate_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1071 static ssize_t calibrate_store(struct device *dev,
1072 			       struct device_attribute *attr,
1073 			       const char *buf, size_t count)
1074 {
1075 	struct i2c_client *client = to_i2c_client(dev);
1076 	struct elants_data *ts = i2c_get_clientdata(client);
1077 	int error;
1078 
1079 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1080 	if (error)
1081 		return error;
1082 
1083 	error = elants_i2c_calibrate(ts);
1084 
1085 	mutex_unlock(&ts->sysfs_mutex);
1086 	return error ?: count;
1087 }
1088 
write_update_fw(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1089 static ssize_t write_update_fw(struct device *dev,
1090 			       struct device_attribute *attr,
1091 			       const char *buf, size_t count)
1092 {
1093 	struct i2c_client *client = to_i2c_client(dev);
1094 	struct elants_data *ts = i2c_get_clientdata(client);
1095 	int error;
1096 
1097 	error = mutex_lock_interruptible(&ts->sysfs_mutex);
1098 	if (error)
1099 		return error;
1100 
1101 	error = elants_i2c_fw_update(ts);
1102 	dev_dbg(dev, "firmware update result: %d\n", error);
1103 
1104 	mutex_unlock(&ts->sysfs_mutex);
1105 	return error ?: count;
1106 }
1107 
show_iap_mode(struct device * dev,struct device_attribute * attr,char * buf)1108 static ssize_t show_iap_mode(struct device *dev,
1109 			     struct device_attribute *attr, char *buf)
1110 {
1111 	struct i2c_client *client = to_i2c_client(dev);
1112 	struct elants_data *ts = i2c_get_clientdata(client);
1113 
1114 	return sprintf(buf, "%s\n",
1115 		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
1116 				"Normal" : "Recovery");
1117 }
1118 
show_calibration_count(struct device * dev,struct device_attribute * attr,char * buf)1119 static ssize_t show_calibration_count(struct device *dev,
1120 				      struct device_attribute *attr, char *buf)
1121 {
1122 	struct i2c_client *client = to_i2c_client(dev);
1123 	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
1124 	u8 resp[HEADER_SIZE];
1125 	u16 rek_count;
1126 	int error;
1127 
1128 	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
1129 					   resp, sizeof(resp), 1,
1130 					   "read ReK status");
1131 	if (error)
1132 		return sprintf(buf, "%d\n", error);
1133 
1134 	rek_count = get_unaligned_be16(&resp[2]);
1135 	return sprintf(buf, "0x%04x\n", rek_count);
1136 }
1137 
1138 static DEVICE_ATTR_WO(calibrate);
1139 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1140 static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
1141 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1142 
1143 struct elants_version_attribute {
1144 	struct device_attribute dattr;
1145 	size_t field_offset;
1146 	size_t field_size;
1147 };
1148 
1149 #define __ELANTS_FIELD_SIZE(_field)					\
1150 	sizeof(((struct elants_data *)NULL)->_field)
1151 #define __ELANTS_VERIFY_SIZE(_field)					\
1152 	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
1153 	 __ELANTS_FIELD_SIZE(_field))
1154 #define ELANTS_VERSION_ATTR(_field)					\
1155 	struct elants_version_attribute elants_ver_attr_##_field = {	\
1156 		.dattr = __ATTR(_field, S_IRUGO,			\
1157 				elants_version_attribute_show, NULL),	\
1158 		.field_offset = offsetof(struct elants_data, _field),	\
1159 		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
1160 	}
1161 
elants_version_attribute_show(struct device * dev,struct device_attribute * dattr,char * buf)1162 static ssize_t elants_version_attribute_show(struct device *dev,
1163 					     struct device_attribute *dattr,
1164 					     char *buf)
1165 {
1166 	struct i2c_client *client = to_i2c_client(dev);
1167 	struct elants_data *ts = i2c_get_clientdata(client);
1168 	struct elants_version_attribute *attr =
1169 		container_of(dattr, struct elants_version_attribute, dattr);
1170 	u8 *field = (u8 *)((char *)ts + attr->field_offset);
1171 	unsigned int fmt_size;
1172 	unsigned int val;
1173 
1174 	if (attr->field_size == 1) {
1175 		val = *field;
1176 		fmt_size = 2; /* 2 HEX digits */
1177 	} else {
1178 		val = *(u16 *)field;
1179 		fmt_size = 4; /* 4 HEX digits */
1180 	}
1181 
1182 	return sprintf(buf, "%0*x\n", fmt_size, val);
1183 }
1184 
1185 static ELANTS_VERSION_ATTR(fw_version);
1186 static ELANTS_VERSION_ATTR(hw_version);
1187 static ELANTS_VERSION_ATTR(test_version);
1188 static ELANTS_VERSION_ATTR(solution_version);
1189 static ELANTS_VERSION_ATTR(bc_version);
1190 static ELANTS_VERSION_ATTR(iap_version);
1191 
1192 static struct attribute *elants_attributes[] = {
1193 	&dev_attr_calibrate.attr,
1194 	&dev_attr_update_fw.attr,
1195 	&dev_attr_iap_mode.attr,
1196 	&dev_attr_calibration_count.attr,
1197 
1198 	&elants_ver_attr_fw_version.dattr.attr,
1199 	&elants_ver_attr_hw_version.dattr.attr,
1200 	&elants_ver_attr_test_version.dattr.attr,
1201 	&elants_ver_attr_solution_version.dattr.attr,
1202 	&elants_ver_attr_bc_version.dattr.attr,
1203 	&elants_ver_attr_iap_version.dattr.attr,
1204 	NULL
1205 };
1206 
1207 static const struct attribute_group elants_attribute_group = {
1208 	.attrs = elants_attributes,
1209 };
1210 
elants_i2c_power_on(struct elants_data * ts)1211 static int elants_i2c_power_on(struct elants_data *ts)
1212 {
1213 	int error;
1214 
1215 	/*
1216 	 * If we do not have reset gpio assume platform firmware
1217 	 * controls regulators and does power them on for us.
1218 	 */
1219 	if (IS_ERR_OR_NULL(ts->reset_gpio))
1220 		return 0;
1221 
1222 	gpiod_set_value_cansleep(ts->reset_gpio, 1);
1223 
1224 	error = regulator_enable(ts->vcc33);
1225 	if (error) {
1226 		dev_err(&ts->client->dev,
1227 			"failed to enable vcc33 regulator: %d\n",
1228 			error);
1229 		goto release_reset_gpio;
1230 	}
1231 
1232 	error = regulator_enable(ts->vccio);
1233 	if (error) {
1234 		dev_err(&ts->client->dev,
1235 			"failed to enable vccio regulator: %d\n",
1236 			error);
1237 		regulator_disable(ts->vcc33);
1238 		goto release_reset_gpio;
1239 	}
1240 
1241 	/*
1242 	 * We need to wait a bit after powering on controller before
1243 	 * we are allowed to release reset GPIO.
1244 	 */
1245 	udelay(ELAN_POWERON_DELAY_USEC);
1246 
1247 release_reset_gpio:
1248 	gpiod_set_value_cansleep(ts->reset_gpio, 0);
1249 	if (error)
1250 		return error;
1251 
1252 	msleep(ELAN_RESET_DELAY_MSEC);
1253 
1254 	return 0;
1255 }
1256 
elants_i2c_power_off(void * _data)1257 static void elants_i2c_power_off(void *_data)
1258 {
1259 	struct elants_data *ts = _data;
1260 
1261 	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1262 		/*
1263 		 * Activate reset gpio to prevent leakage through the
1264 		 * pin once we shut off power to the controller.
1265 		 */
1266 		gpiod_set_value_cansleep(ts->reset_gpio, 1);
1267 		regulator_disable(ts->vccio);
1268 		regulator_disable(ts->vcc33);
1269 	}
1270 }
1271 
1272 #ifdef CONFIG_ACPI
1273 static const struct acpi_device_id i2c_hid_ids[] = {
1274 	{"ACPI0C50", 0 },
1275 	{"PNP0C50", 0 },
1276 	{ },
1277 };
1278 
1279 static const guid_t i2c_hid_guid =
1280 	GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
1281 		  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
1282 
elants_acpi_is_hid_device(struct device * dev)1283 static bool elants_acpi_is_hid_device(struct device *dev)
1284 {
1285 	acpi_handle handle = ACPI_HANDLE(dev);
1286 	union acpi_object *obj;
1287 
1288 	if (acpi_match_device_ids(ACPI_COMPANION(dev), i2c_hid_ids))
1289 		return false;
1290 
1291 	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, ACPI_TYPE_INTEGER);
1292 	if (obj) {
1293 		ACPI_FREE(obj);
1294 		return true;
1295 	}
1296 
1297 	return false;
1298 }
1299 #else
elants_acpi_is_hid_device(struct device * dev)1300 static bool elants_acpi_is_hid_device(struct device *dev)
1301 {
1302 	return false;
1303 }
1304 #endif
1305 
elants_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)1306 static int elants_i2c_probe(struct i2c_client *client,
1307 			    const struct i2c_device_id *id)
1308 {
1309 	union i2c_smbus_data dummy;
1310 	struct elants_data *ts;
1311 	unsigned long irqflags;
1312 	int error;
1313 
1314 	/* Don't bind to i2c-hid compatible devices, these are handled by the i2c-hid drv. */
1315 	if (elants_acpi_is_hid_device(&client->dev)) {
1316 		dev_warn(&client->dev, "This device appears to be an I2C-HID device, not binding\n");
1317 		return -ENODEV;
1318 	}
1319 
1320 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1321 		dev_err(&client->dev, "I2C check functionality error\n");
1322 		return -ENXIO;
1323 	}
1324 
1325 	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1326 	if (!ts)
1327 		return -ENOMEM;
1328 
1329 	mutex_init(&ts->sysfs_mutex);
1330 	init_completion(&ts->cmd_done);
1331 
1332 	ts->client = client;
1333 	i2c_set_clientdata(client, ts);
1334 
1335 	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1336 	if (IS_ERR(ts->vcc33)) {
1337 		error = PTR_ERR(ts->vcc33);
1338 		if (error != -EPROBE_DEFER)
1339 			dev_err(&client->dev,
1340 				"Failed to get 'vcc33' regulator: %d\n",
1341 				error);
1342 		return error;
1343 	}
1344 
1345 	ts->vccio = devm_regulator_get(&client->dev, "vccio");
1346 	if (IS_ERR(ts->vccio)) {
1347 		error = PTR_ERR(ts->vccio);
1348 		if (error != -EPROBE_DEFER)
1349 			dev_err(&client->dev,
1350 				"Failed to get 'vccio' regulator: %d\n",
1351 				error);
1352 		return error;
1353 	}
1354 
1355 	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1356 	if (IS_ERR(ts->reset_gpio)) {
1357 		error = PTR_ERR(ts->reset_gpio);
1358 
1359 		if (error == -EPROBE_DEFER)
1360 			return error;
1361 
1362 		if (error != -ENOENT && error != -ENOSYS) {
1363 			dev_err(&client->dev,
1364 				"failed to get reset gpio: %d\n",
1365 				error);
1366 			return error;
1367 		}
1368 
1369 		ts->keep_power_in_suspend = true;
1370 	}
1371 
1372 	error = elants_i2c_power_on(ts);
1373 	if (error)
1374 		return error;
1375 
1376 	error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1377 	if (error) {
1378 		dev_err(&client->dev,
1379 			"failed to install power off action: %d\n", error);
1380 		elants_i2c_power_off(ts);
1381 		return error;
1382 	}
1383 
1384 	/* Make sure there is something at this address */
1385 	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1386 			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1387 		dev_err(&client->dev, "nothing at this address\n");
1388 		return -ENXIO;
1389 	}
1390 
1391 	error = elants_i2c_initialize(ts);
1392 	if (error) {
1393 		dev_err(&client->dev, "failed to initialize: %d\n", error);
1394 		return error;
1395 	}
1396 
1397 	ts->input = devm_input_allocate_device(&client->dev);
1398 	if (!ts->input) {
1399 		dev_err(&client->dev, "Failed to allocate input device\n");
1400 		return -ENOMEM;
1401 	}
1402 
1403 	ts->input->name = "Elan Touchscreen";
1404 	ts->input->id.bustype = BUS_I2C;
1405 
1406 	/* Multitouch input params setup */
1407 
1408 	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1409 	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1410 	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1411 	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1412 	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
1413 			     0, MT_TOOL_PALM, 0, 0);
1414 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1415 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1416 	if (ts->major_res > 0)
1417 		input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->major_res);
1418 
1419 	touchscreen_parse_properties(ts->input, true, &ts->prop);
1420 
1421 	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1422 				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1423 	if (error) {
1424 		dev_err(&client->dev,
1425 			"failed to initialize MT slots: %d\n", error);
1426 		return error;
1427 	}
1428 
1429 	error = input_register_device(ts->input);
1430 	if (error) {
1431 		dev_err(&client->dev,
1432 			"unable to register input device: %d\n", error);
1433 		return error;
1434 	}
1435 
1436 	/*
1437 	 * Platform code (ACPI, DTS) should normally set up interrupt
1438 	 * for us, but in case it did not let's fall back to using falling
1439 	 * edge to be compatible with older Chromebooks.
1440 	 */
1441 	irqflags = irq_get_trigger_type(client->irq);
1442 	if (!irqflags)
1443 		irqflags = IRQF_TRIGGER_FALLING;
1444 
1445 	error = devm_request_threaded_irq(&client->dev, client->irq,
1446 					  NULL, elants_i2c_irq,
1447 					  irqflags | IRQF_ONESHOT,
1448 					  client->name, ts);
1449 	if (error) {
1450 		dev_err(&client->dev, "Failed to register interrupt\n");
1451 		return error;
1452 	}
1453 
1454 	/*
1455 	 * Systems using device tree should set up wakeup via DTS,
1456 	 * the rest will configure device as wakeup source by default.
1457 	 */
1458 	if (!client->dev.of_node)
1459 		device_init_wakeup(&client->dev, true);
1460 
1461 	error = devm_device_add_group(&client->dev, &elants_attribute_group);
1462 	if (error) {
1463 		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1464 			error);
1465 		return error;
1466 	}
1467 
1468 	return 0;
1469 }
1470 
elants_i2c_suspend(struct device * dev)1471 static int __maybe_unused elants_i2c_suspend(struct device *dev)
1472 {
1473 	struct i2c_client *client = to_i2c_client(dev);
1474 	struct elants_data *ts = i2c_get_clientdata(client);
1475 	const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
1476 	int retry_cnt;
1477 	int error;
1478 
1479 	/* Command not support in IAP recovery mode */
1480 	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1481 		return -EBUSY;
1482 
1483 	disable_irq(client->irq);
1484 
1485 	if (device_may_wakeup(dev)) {
1486 		/*
1487 		 * The device will automatically enter idle mode
1488 		 * that has reduced power consumption.
1489 		 */
1490 		ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1491 	} else if (ts->keep_power_in_suspend) {
1492 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1493 			error = elants_i2c_send(client, set_sleep_cmd,
1494 						sizeof(set_sleep_cmd));
1495 			if (!error)
1496 				break;
1497 
1498 			dev_err(&client->dev,
1499 				"suspend command failed: %d\n", error);
1500 		}
1501 	} else {
1502 		elants_i2c_power_off(ts);
1503 	}
1504 
1505 	return 0;
1506 }
1507 
elants_i2c_resume(struct device * dev)1508 static int __maybe_unused elants_i2c_resume(struct device *dev)
1509 {
1510 	struct i2c_client *client = to_i2c_client(dev);
1511 	struct elants_data *ts = i2c_get_clientdata(client);
1512 	const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
1513 	int retry_cnt;
1514 	int error;
1515 
1516 	if (device_may_wakeup(dev)) {
1517 		if (ts->wake_irq_enabled)
1518 			disable_irq_wake(client->irq);
1519 		elants_i2c_sw_reset(client);
1520 	} else if (ts->keep_power_in_suspend) {
1521 		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1522 			error = elants_i2c_send(client, set_active_cmd,
1523 						sizeof(set_active_cmd));
1524 			if (!error)
1525 				break;
1526 
1527 			dev_err(&client->dev,
1528 				"resume command failed: %d\n", error);
1529 		}
1530 	} else {
1531 		elants_i2c_power_on(ts);
1532 		elants_i2c_initialize(ts);
1533 	}
1534 
1535 	ts->state = ELAN_STATE_NORMAL;
1536 	enable_irq(client->irq);
1537 
1538 	return 0;
1539 }
1540 
1541 static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1542 			 elants_i2c_suspend, elants_i2c_resume);
1543 
1544 static const struct i2c_device_id elants_i2c_id[] = {
1545 	{ DEVICE_NAME, 0 },
1546 	{ }
1547 };
1548 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1549 
1550 #ifdef CONFIG_ACPI
1551 static const struct acpi_device_id elants_acpi_id[] = {
1552 	{ "ELAN0001", 0 },
1553 	{ }
1554 };
1555 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1556 #endif
1557 
1558 #ifdef CONFIG_OF
1559 static const struct of_device_id elants_of_match[] = {
1560 	{ .compatible = "elan,ekth3500" },
1561 	{ /* sentinel */ }
1562 };
1563 MODULE_DEVICE_TABLE(of, elants_of_match);
1564 #endif
1565 
1566 static struct i2c_driver elants_i2c_driver = {
1567 	.probe = elants_i2c_probe,
1568 	.id_table = elants_i2c_id,
1569 	.driver = {
1570 		.name = DEVICE_NAME,
1571 		.pm = &elants_i2c_pm_ops,
1572 		.acpi_match_table = ACPI_PTR(elants_acpi_id),
1573 		.of_match_table = of_match_ptr(elants_of_match),
1574 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1575 	},
1576 };
1577 module_i2c_driver(elants_i2c_driver);
1578 
1579 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1580 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1581 MODULE_LICENSE("GPL");
1582