Loading...
1/*
2 * Elan Microelectronics touch panels with I2C interface
3 *
4 * Copyright (C) 2014 Elan Microelectronics Corporation.
5 * Scott Liu <scott.liu@emc.com.tw>
6 *
7 * This code is partly based on hid-multitouch.c:
8 *
9 * Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
10 * Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
11 * Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
12 *
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 * This software is licensed under the terms of the GNU General Public
23 * License version 2, as published by the Free Software Foundation, and
24 * may be copied, distributed, and modified under those terms.
25 */
26
27#include <linux/module.h>
28#include <linux/input.h>
29#include <linux/interrupt.h>
30#include <linux/platform_device.h>
31#include <linux/async.h>
32#include <linux/i2c.h>
33#include <linux/delay.h>
34#include <linux/uaccess.h>
35#include <linux/buffer_head.h>
36#include <linux/slab.h>
37#include <linux/firmware.h>
38#include <linux/input/mt.h>
39#include <linux/acpi.h>
40#include <linux/of.h>
41#include <linux/gpio/consumer.h>
42#include <linux/regulator/consumer.h>
43#include <asm/unaligned.h>
44
45/* Device, Driver information */
46#define DEVICE_NAME "elants_i2c"
47#define DRV_VERSION "1.0.9"
48
49/* Convert from rows or columns into resolution */
50#define ELAN_TS_RESOLUTION(n, m) (((n) - 1) * (m))
51
52/* FW header data */
53#define HEADER_SIZE 4
54#define FW_HDR_TYPE 0
55#define FW_HDR_COUNT 1
56#define FW_HDR_LENGTH 2
57
58/* Buffer mode Queue Header information */
59#define QUEUE_HEADER_SINGLE 0x62
60#define QUEUE_HEADER_NORMAL 0X63
61#define QUEUE_HEADER_WAIT 0x64
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_RESP 0x52
68#define CMD_HEADER_6B_RESP 0x9B
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_CHECKSUM 34
80#define FW_POS_WIDTH 35
81#define FW_POS_PRESSURE 45
82
83#define HEADER_REPORT_10_FINGER 0x62
84
85/* Header (4 bytes) plus 3 fill 10-finger packets */
86#define MAX_PACKET_SIZE 169
87
88#define BOOT_TIME_DELAY_MS 50
89
90/* FW read command, 0x53 0x?? 0x0, 0x01 */
91#define E_ELAN_INFO_FW_VER 0x00
92#define E_ELAN_INFO_BC_VER 0x10
93#define E_ELAN_INFO_TEST_VER 0xE0
94#define E_ELAN_INFO_FW_ID 0xF0
95#define E_INFO_OSR 0xD6
96#define E_INFO_PHY_SCAN 0xD7
97#define E_INFO_PHY_DRIVER 0xD8
98
99#define MAX_RETRIES 3
100#define MAX_FW_UPDATE_RETRIES 30
101
102#define ELAN_FW_PAGESIZE 132
103
104/* calibration timeout definition */
105#define ELAN_CALI_TIMEOUT_MSEC 12000
106
107#define ELAN_POWERON_DELAY_USEC 500
108#define ELAN_RESET_DELAY_MSEC 20
109
110enum elants_state {
111 ELAN_STATE_NORMAL,
112 ELAN_WAIT_QUEUE_HEADER,
113 ELAN_WAIT_RECALIBRATION,
114};
115
116enum elants_iap_mode {
117 ELAN_IAP_OPERATIONAL,
118 ELAN_IAP_RECOVERY,
119};
120
121/* struct elants_data - represents state of Elan touchscreen device */
122struct elants_data {
123 struct i2c_client *client;
124 struct input_dev *input;
125
126 struct regulator *vcc33;
127 struct regulator *vccio;
128 struct gpio_desc *reset_gpio;
129
130 u16 fw_version;
131 u8 test_version;
132 u8 solution_version;
133 u8 bc_version;
134 u8 iap_version;
135 u16 hw_version;
136 unsigned int x_res; /* resolution in units/mm */
137 unsigned int y_res;
138 unsigned int x_max;
139 unsigned int y_max;
140
141 enum elants_state state;
142 enum elants_iap_mode iap_mode;
143
144 /* Guards against concurrent access to the device via sysfs */
145 struct mutex sysfs_mutex;
146
147 u8 cmd_resp[HEADER_SIZE];
148 struct completion cmd_done;
149
150 u8 buf[MAX_PACKET_SIZE];
151
152 bool wake_irq_enabled;
153 bool keep_power_in_suspend;
154};
155
156static int elants_i2c_send(struct i2c_client *client,
157 const void *data, size_t size)
158{
159 int ret;
160
161 ret = i2c_master_send(client, data, size);
162 if (ret == size)
163 return 0;
164
165 if (ret >= 0)
166 ret = -EIO;
167
168 dev_err(&client->dev, "%s failed (%*ph): %d\n",
169 __func__, (int)size, data, ret);
170
171 return ret;
172}
173
174static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
175{
176 int ret;
177
178 ret = i2c_master_recv(client, data, size);
179 if (ret == size)
180 return 0;
181
182 if (ret >= 0)
183 ret = -EIO;
184
185 dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
186
187 return ret;
188}
189
190static int elants_i2c_execute_command(struct i2c_client *client,
191 const u8 *cmd, size_t cmd_size,
192 u8 *resp, size_t resp_size)
193{
194 struct i2c_msg msgs[2];
195 int ret;
196 u8 expected_response;
197
198 switch (cmd[0]) {
199 case CMD_HEADER_READ:
200 expected_response = CMD_HEADER_RESP;
201 break;
202
203 case CMD_HEADER_6B_READ:
204 expected_response = CMD_HEADER_6B_RESP;
205 break;
206
207 default:
208 dev_err(&client->dev, "%s: invalid command %*ph\n",
209 __func__, (int)cmd_size, cmd);
210 return -EINVAL;
211 }
212
213 msgs[0].addr = client->addr;
214 msgs[0].flags = client->flags & I2C_M_TEN;
215 msgs[0].len = cmd_size;
216 msgs[0].buf = (u8 *)cmd;
217
218 msgs[1].addr = client->addr;
219 msgs[1].flags = client->flags & I2C_M_TEN;
220 msgs[1].flags |= I2C_M_RD;
221 msgs[1].len = resp_size;
222 msgs[1].buf = resp;
223
224 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
225 if (ret < 0)
226 return ret;
227
228 if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
229 return -EIO;
230
231 return 0;
232}
233
234static int elants_i2c_calibrate(struct elants_data *ts)
235{
236 struct i2c_client *client = ts->client;
237 int ret, error;
238 static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
239 static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
240 static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
241
242 disable_irq(client->irq);
243
244 ts->state = ELAN_WAIT_RECALIBRATION;
245 reinit_completion(&ts->cmd_done);
246
247 elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
248 elants_i2c_send(client, rek, sizeof(rek));
249
250 enable_irq(client->irq);
251
252 ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
253 msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
254
255 ts->state = ELAN_STATE_NORMAL;
256
257 if (ret <= 0) {
258 error = ret < 0 ? ret : -ETIMEDOUT;
259 dev_err(&client->dev,
260 "error while waiting for calibration to complete: %d\n",
261 error);
262 return error;
263 }
264
265 if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
266 dev_err(&client->dev,
267 "unexpected calibration response: %*ph\n",
268 (int)sizeof(ts->cmd_resp), ts->cmd_resp);
269 return -EINVAL;
270 }
271
272 return 0;
273}
274
275static int elants_i2c_sw_reset(struct i2c_client *client)
276{
277 const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
278 int error;
279
280 error = elants_i2c_send(client, soft_rst_cmd,
281 sizeof(soft_rst_cmd));
282 if (error) {
283 dev_err(&client->dev, "software reset failed: %d\n", error);
284 return error;
285 }
286
287 /*
288 * We should wait at least 10 msec (but no more than 40) before
289 * sending fastboot or IAP command to the device.
290 */
291 msleep(30);
292
293 return 0;
294}
295
296static u16 elants_i2c_parse_version(u8 *buf)
297{
298 return get_unaligned_be32(buf) >> 4;
299}
300
301static int elants_i2c_query_fw_id(struct elants_data *ts)
302{
303 struct i2c_client *client = ts->client;
304 int error, retry_cnt;
305 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
306 u8 resp[HEADER_SIZE];
307
308 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
309 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
310 resp, sizeof(resp));
311 if (!error) {
312 ts->hw_version = elants_i2c_parse_version(resp);
313 if (ts->hw_version != 0xffff)
314 return 0;
315 }
316
317 dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
318 error, (int)sizeof(resp), resp);
319 }
320
321 dev_err(&client->dev,
322 "Failed to read fw id or fw id is invalid\n");
323
324 return -EINVAL;
325}
326
327static int elants_i2c_query_fw_version(struct elants_data *ts)
328{
329 struct i2c_client *client = ts->client;
330 int error, retry_cnt;
331 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
332 u8 resp[HEADER_SIZE];
333
334 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
335 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
336 resp, sizeof(resp));
337 if (!error) {
338 ts->fw_version = elants_i2c_parse_version(resp);
339 if (ts->fw_version != 0x0000 &&
340 ts->fw_version != 0xffff)
341 return 0;
342 }
343
344 dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
345 error, (int)sizeof(resp), resp);
346 }
347
348 dev_err(&client->dev,
349 "Failed to read fw version or fw version is invalid\n");
350
351 return -EINVAL;
352}
353
354static int elants_i2c_query_test_version(struct elants_data *ts)
355{
356 struct i2c_client *client = ts->client;
357 int error, retry_cnt;
358 u16 version;
359 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
360 u8 resp[HEADER_SIZE];
361
362 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
363 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
364 resp, sizeof(resp));
365 if (!error) {
366 version = elants_i2c_parse_version(resp);
367 ts->test_version = version >> 8;
368 ts->solution_version = version & 0xff;
369
370 return 0;
371 }
372
373 dev_dbg(&client->dev,
374 "read test version error rc=%d, buf=%*phC\n",
375 error, (int)sizeof(resp), resp);
376 }
377
378 dev_err(&client->dev, "Failed to read test version\n");
379
380 return -EINVAL;
381}
382
383static int elants_i2c_query_bc_version(struct elants_data *ts)
384{
385 struct i2c_client *client = ts->client;
386 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
387 u8 resp[HEADER_SIZE];
388 u16 version;
389 int error;
390
391 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
392 resp, sizeof(resp));
393 if (error) {
394 dev_err(&client->dev,
395 "read BC version error=%d, buf=%*phC\n",
396 error, (int)sizeof(resp), resp);
397 return error;
398 }
399
400 version = elants_i2c_parse_version(resp);
401 ts->bc_version = version >> 8;
402 ts->iap_version = version & 0xff;
403
404 return 0;
405}
406
407static int elants_i2c_query_ts_info(struct elants_data *ts)
408{
409 struct i2c_client *client = ts->client;
410 int error;
411 u8 resp[17];
412 u16 phy_x, phy_y, rows, cols, osr;
413 const u8 get_resolution_cmd[] = {
414 CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
415 };
416 const u8 get_osr_cmd[] = {
417 CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
418 };
419 const u8 get_physical_scan_cmd[] = {
420 CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
421 };
422 const u8 get_physical_drive_cmd[] = {
423 CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
424 };
425
426 /* Get trace number */
427 error = elants_i2c_execute_command(client,
428 get_resolution_cmd,
429 sizeof(get_resolution_cmd),
430 resp, sizeof(resp));
431 if (error) {
432 dev_err(&client->dev, "get resolution command failed: %d\n",
433 error);
434 return error;
435 }
436
437 rows = resp[2] + resp[6] + resp[10];
438 cols = resp[3] + resp[7] + resp[11];
439
440 /* Process mm_to_pixel information */
441 error = elants_i2c_execute_command(client,
442 get_osr_cmd, sizeof(get_osr_cmd),
443 resp, sizeof(resp));
444 if (error) {
445 dev_err(&client->dev, "get osr command failed: %d\n",
446 error);
447 return error;
448 }
449
450 osr = resp[3];
451
452 error = elants_i2c_execute_command(client,
453 get_physical_scan_cmd,
454 sizeof(get_physical_scan_cmd),
455 resp, sizeof(resp));
456 if (error) {
457 dev_err(&client->dev, "get physical scan command failed: %d\n",
458 error);
459 return error;
460 }
461
462 phy_x = get_unaligned_be16(&resp[2]);
463
464 error = elants_i2c_execute_command(client,
465 get_physical_drive_cmd,
466 sizeof(get_physical_drive_cmd),
467 resp, sizeof(resp));
468 if (error) {
469 dev_err(&client->dev, "get physical drive command failed: %d\n",
470 error);
471 return error;
472 }
473
474 phy_y = get_unaligned_be16(&resp[2]);
475
476 dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
477
478 if (rows == 0 || cols == 0 || osr == 0) {
479 dev_warn(&client->dev,
480 "invalid trace number data: %d, %d, %d\n",
481 rows, cols, osr);
482 } else {
483 /* translate trace number to TS resolution */
484 ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
485 ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
486 ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
487 ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
488 }
489
490 return 0;
491}
492
493static int elants_i2c_fastboot(struct i2c_client *client)
494{
495 const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
496 int error;
497
498 error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
499 if (error) {
500 dev_err(&client->dev, "boot failed: %d\n", error);
501 return error;
502 }
503
504 dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
505 return 0;
506}
507
508static int elants_i2c_initialize(struct elants_data *ts)
509{
510 struct i2c_client *client = ts->client;
511 int error, retry_cnt;
512 const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
513 const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
514 u8 buf[HEADER_SIZE];
515
516 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
517 error = elants_i2c_sw_reset(client);
518 if (error) {
519 /* Continue initializing if it's the last try */
520 if (retry_cnt < MAX_RETRIES - 1)
521 continue;
522 }
523
524 error = elants_i2c_fastboot(client);
525 if (error) {
526 /* Continue initializing if it's the last try */
527 if (retry_cnt < MAX_RETRIES - 1)
528 continue;
529 }
530
531 /* Wait for Hello packet */
532 msleep(BOOT_TIME_DELAY_MS);
533
534 error = elants_i2c_read(client, buf, sizeof(buf));
535 if (error) {
536 dev_err(&client->dev,
537 "failed to read 'hello' packet: %d\n", error);
538 } else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
539 ts->iap_mode = ELAN_IAP_OPERATIONAL;
540 break;
541 } else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
542 /*
543 * Setting error code will mark device
544 * in recovery mode below.
545 */
546 error = -EIO;
547 break;
548 } else {
549 error = -EINVAL;
550 dev_err(&client->dev,
551 "invalid 'hello' packet: %*ph\n",
552 (int)sizeof(buf), buf);
553 }
554 }
555
556 if (!error)
557 error = elants_i2c_query_fw_id(ts);
558 if (!error)
559 error = elants_i2c_query_fw_version(ts);
560
561 if (error) {
562 ts->iap_mode = ELAN_IAP_RECOVERY;
563 } else {
564 elants_i2c_query_test_version(ts);
565 elants_i2c_query_bc_version(ts);
566 elants_i2c_query_ts_info(ts);
567 }
568
569 return 0;
570}
571
572/*
573 * Firmware update interface.
574 */
575
576static int elants_i2c_fw_write_page(struct i2c_client *client,
577 const void *page)
578{
579 const u8 ack_ok[] = { 0xaa, 0xaa };
580 u8 buf[2];
581 int retry;
582 int error;
583
584 for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
585 error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
586 if (error) {
587 dev_err(&client->dev,
588 "IAP Write Page failed: %d\n", error);
589 continue;
590 }
591
592 error = elants_i2c_read(client, buf, 2);
593 if (error) {
594 dev_err(&client->dev,
595 "IAP Ack read failed: %d\n", error);
596 return error;
597 }
598
599 if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
600 return 0;
601
602 error = -EIO;
603 dev_err(&client->dev,
604 "IAP Get Ack Error [%02x:%02x]\n",
605 buf[0], buf[1]);
606 }
607
608 return error;
609}
610
611static int elants_i2c_do_update_firmware(struct i2c_client *client,
612 const struct firmware *fw,
613 bool force)
614{
615 const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
616 const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
617 const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
618 const u8 close_idle[] = {0x54, 0x2c, 0x01, 0x01};
619 u8 buf[HEADER_SIZE];
620 u16 send_id;
621 int page, n_fw_pages;
622 int error;
623
624 /* Recovery mode detection! */
625 if (force) {
626 dev_dbg(&client->dev, "Recovery mode procedure\n");
627 error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
628 } else {
629 /* Start IAP Procedure */
630 dev_dbg(&client->dev, "Normal IAP procedure\n");
631 /* Close idle mode */
632 error = elants_i2c_send(client, close_idle, sizeof(close_idle));
633 if (error)
634 dev_err(&client->dev, "Failed close idle: %d\n", error);
635 msleep(60);
636 elants_i2c_sw_reset(client);
637 msleep(20);
638 error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
639 }
640
641 if (error) {
642 dev_err(&client->dev, "failed to enter IAP mode: %d\n", error);
643 return error;
644 }
645
646 msleep(20);
647
648 /* check IAP state */
649 error = elants_i2c_read(client, buf, 4);
650 if (error) {
651 dev_err(&client->dev,
652 "failed to read IAP acknowledgement: %d\n",
653 error);
654 return error;
655 }
656
657 if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
658 dev_err(&client->dev,
659 "failed to enter IAP: %*ph (expected %*ph)\n",
660 (int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
661 return -EIO;
662 }
663
664 dev_info(&client->dev, "successfully entered IAP mode");
665
666 send_id = client->addr;
667 error = elants_i2c_send(client, &send_id, 1);
668 if (error) {
669 dev_err(&client->dev, "sending dummy byte failed: %d\n",
670 error);
671 return error;
672 }
673
674 /* Clear the last page of Master */
675 error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
676 if (error) {
677 dev_err(&client->dev, "clearing of the last page failed: %d\n",
678 error);
679 return error;
680 }
681
682 error = elants_i2c_read(client, buf, 2);
683 if (error) {
684 dev_err(&client->dev,
685 "failed to read ACK for clearing the last page: %d\n",
686 error);
687 return error;
688 }
689
690 n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
691 dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
692
693 for (page = 0; page < n_fw_pages; page++) {
694 error = elants_i2c_fw_write_page(client,
695 fw->data + page * ELAN_FW_PAGESIZE);
696 if (error) {
697 dev_err(&client->dev,
698 "failed to write FW page %d: %d\n",
699 page, error);
700 return error;
701 }
702 }
703
704 /* Old iap needs to wait 200ms for WDT and rest is for hello packets */
705 msleep(300);
706
707 dev_info(&client->dev, "firmware update completed\n");
708 return 0;
709}
710
711static int elants_i2c_fw_update(struct elants_data *ts)
712{
713 struct i2c_client *client = ts->client;
714 const struct firmware *fw;
715 char *fw_name;
716 int error;
717
718 fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
719 if (!fw_name)
720 return -ENOMEM;
721
722 dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
723 error = request_firmware(&fw, fw_name, &client->dev);
724 kfree(fw_name);
725 if (error) {
726 dev_err(&client->dev, "failed to request firmware: %d\n",
727 error);
728 return error;
729 }
730
731 if (fw->size % ELAN_FW_PAGESIZE) {
732 dev_err(&client->dev, "invalid firmware length: %zu\n",
733 fw->size);
734 error = -EINVAL;
735 goto out;
736 }
737
738 disable_irq(client->irq);
739
740 error = elants_i2c_do_update_firmware(client, fw,
741 ts->iap_mode == ELAN_IAP_RECOVERY);
742 if (error) {
743 dev_err(&client->dev, "firmware update failed: %d\n", error);
744 ts->iap_mode = ELAN_IAP_RECOVERY;
745 goto out_enable_irq;
746 }
747
748 error = elants_i2c_initialize(ts);
749 if (error) {
750 dev_err(&client->dev,
751 "failed to initialize device after firmware update: %d\n",
752 error);
753 ts->iap_mode = ELAN_IAP_RECOVERY;
754 goto out_enable_irq;
755 }
756
757 ts->iap_mode = ELAN_IAP_OPERATIONAL;
758
759out_enable_irq:
760 ts->state = ELAN_STATE_NORMAL;
761 enable_irq(client->irq);
762 msleep(100);
763
764 if (!error)
765 elants_i2c_calibrate(ts);
766out:
767 release_firmware(fw);
768 return error;
769}
770
771/*
772 * Event reporting.
773 */
774
775static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
776{
777 struct input_dev *input = ts->input;
778 unsigned int n_fingers;
779 u16 finger_state;
780 int i;
781
782 n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
783 finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
784 buf[FW_POS_STATE];
785
786 dev_dbg(&ts->client->dev,
787 "n_fingers: %u, state: %04x\n", n_fingers, finger_state);
788
789 for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
790 if (finger_state & 1) {
791 unsigned int x, y, p, w;
792 u8 *pos;
793
794 pos = &buf[FW_POS_XY + i * 3];
795 x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
796 y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
797 p = buf[FW_POS_PRESSURE + i];
798 w = buf[FW_POS_WIDTH + i];
799
800 dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
801 i, x, y, p, w);
802
803 input_mt_slot(input, i);
804 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
805 input_event(input, EV_ABS, ABS_MT_POSITION_X, x);
806 input_event(input, EV_ABS, ABS_MT_POSITION_Y, y);
807 input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
808 input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
809
810 n_fingers--;
811 }
812
813 finger_state >>= 1;
814 }
815
816 input_mt_sync_frame(input);
817 input_sync(input);
818}
819
820static u8 elants_i2c_calculate_checksum(u8 *buf)
821{
822 u8 checksum = 0;
823 u8 i;
824
825 for (i = 0; i < FW_POS_CHECKSUM; i++)
826 checksum += buf[i];
827
828 return checksum;
829}
830
831static void elants_i2c_event(struct elants_data *ts, u8 *buf)
832{
833 u8 checksum = elants_i2c_calculate_checksum(buf);
834
835 if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
836 dev_warn(&ts->client->dev,
837 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
838 __func__, buf[FW_POS_HEADER],
839 checksum, buf[FW_POS_CHECKSUM]);
840 else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
841 dev_warn(&ts->client->dev,
842 "%s: unknown packet type: %02x\n",
843 __func__, buf[FW_POS_HEADER]);
844 else
845 elants_i2c_mt_event(ts, buf);
846}
847
848static irqreturn_t elants_i2c_irq(int irq, void *_dev)
849{
850 const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
851 struct elants_data *ts = _dev;
852 struct i2c_client *client = ts->client;
853 int report_count, report_len;
854 int i;
855 int len;
856
857 len = i2c_master_recv(client, ts->buf, sizeof(ts->buf));
858 if (len < 0) {
859 dev_err(&client->dev, "%s: failed to read data: %d\n",
860 __func__, len);
861 goto out;
862 }
863
864 dev_dbg(&client->dev, "%s: packet %*ph\n",
865 __func__, HEADER_SIZE, ts->buf);
866
867 switch (ts->state) {
868 case ELAN_WAIT_RECALIBRATION:
869 if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
870 memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
871 complete(&ts->cmd_done);
872 ts->state = ELAN_STATE_NORMAL;
873 }
874 break;
875
876 case ELAN_WAIT_QUEUE_HEADER:
877 if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
878 break;
879
880 ts->state = ELAN_STATE_NORMAL;
881 /* fall through */
882
883 case ELAN_STATE_NORMAL:
884
885 switch (ts->buf[FW_HDR_TYPE]) {
886 case CMD_HEADER_HELLO:
887 case CMD_HEADER_RESP:
888 case CMD_HEADER_REK:
889 break;
890
891 case QUEUE_HEADER_WAIT:
892 if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
893 dev_err(&client->dev,
894 "invalid wait packet %*ph\n",
895 HEADER_SIZE, ts->buf);
896 } else {
897 ts->state = ELAN_WAIT_QUEUE_HEADER;
898 udelay(30);
899 }
900 break;
901
902 case QUEUE_HEADER_SINGLE:
903 elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
904 break;
905
906 case QUEUE_HEADER_NORMAL:
907 report_count = ts->buf[FW_HDR_COUNT];
908 if (report_count > 3) {
909 dev_err(&client->dev,
910 "too large report count: %*ph\n",
911 HEADER_SIZE, ts->buf);
912 break;
913 }
914
915 report_len = ts->buf[FW_HDR_LENGTH] / report_count;
916 if (report_len != PACKET_SIZE) {
917 dev_err(&client->dev,
918 "mismatching report length: %*ph\n",
919 HEADER_SIZE, ts->buf);
920 break;
921 }
922
923 for (i = 0; i < report_count; i++) {
924 u8 *buf = ts->buf + HEADER_SIZE +
925 i * PACKET_SIZE;
926 elants_i2c_event(ts, buf);
927 }
928 break;
929
930 default:
931 dev_err(&client->dev, "unknown packet %*ph\n",
932 HEADER_SIZE, ts->buf);
933 break;
934 }
935 break;
936 }
937
938out:
939 return IRQ_HANDLED;
940}
941
942/*
943 * sysfs interface
944 */
945static ssize_t calibrate_store(struct device *dev,
946 struct device_attribute *attr,
947 const char *buf, size_t count)
948{
949 struct i2c_client *client = to_i2c_client(dev);
950 struct elants_data *ts = i2c_get_clientdata(client);
951 int error;
952
953 error = mutex_lock_interruptible(&ts->sysfs_mutex);
954 if (error)
955 return error;
956
957 error = elants_i2c_calibrate(ts);
958
959 mutex_unlock(&ts->sysfs_mutex);
960 return error ?: count;
961}
962
963static ssize_t write_update_fw(struct device *dev,
964 struct device_attribute *attr,
965 const char *buf, size_t count)
966{
967 struct i2c_client *client = to_i2c_client(dev);
968 struct elants_data *ts = i2c_get_clientdata(client);
969 int error;
970
971 error = mutex_lock_interruptible(&ts->sysfs_mutex);
972 if (error)
973 return error;
974
975 error = elants_i2c_fw_update(ts);
976 dev_dbg(dev, "firmware update result: %d\n", error);
977
978 mutex_unlock(&ts->sysfs_mutex);
979 return error ?: count;
980}
981
982static ssize_t show_iap_mode(struct device *dev,
983 struct device_attribute *attr, char *buf)
984{
985 struct i2c_client *client = to_i2c_client(dev);
986 struct elants_data *ts = i2c_get_clientdata(client);
987
988 return sprintf(buf, "%s\n",
989 ts->iap_mode == ELAN_IAP_OPERATIONAL ?
990 "Normal" : "Recovery");
991}
992
993static DEVICE_ATTR(calibrate, S_IWUSR, NULL, calibrate_store);
994static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
995static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
996
997struct elants_version_attribute {
998 struct device_attribute dattr;
999 size_t field_offset;
1000 size_t field_size;
1001};
1002
1003#define __ELANTS_FIELD_SIZE(_field) \
1004 sizeof(((struct elants_data *)NULL)->_field)
1005#define __ELANTS_VERIFY_SIZE(_field) \
1006 (BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) + \
1007 __ELANTS_FIELD_SIZE(_field))
1008#define ELANTS_VERSION_ATTR(_field) \
1009 struct elants_version_attribute elants_ver_attr_##_field = { \
1010 .dattr = __ATTR(_field, S_IRUGO, \
1011 elants_version_attribute_show, NULL), \
1012 .field_offset = offsetof(struct elants_data, _field), \
1013 .field_size = __ELANTS_VERIFY_SIZE(_field), \
1014 }
1015
1016static ssize_t elants_version_attribute_show(struct device *dev,
1017 struct device_attribute *dattr,
1018 char *buf)
1019{
1020 struct i2c_client *client = to_i2c_client(dev);
1021 struct elants_data *ts = i2c_get_clientdata(client);
1022 struct elants_version_attribute *attr =
1023 container_of(dattr, struct elants_version_attribute, dattr);
1024 u8 *field = (u8 *)((char *)ts + attr->field_offset);
1025 unsigned int fmt_size;
1026 unsigned int val;
1027
1028 if (attr->field_size == 1) {
1029 val = *field;
1030 fmt_size = 2; /* 2 HEX digits */
1031 } else {
1032 val = *(u16 *)field;
1033 fmt_size = 4; /* 4 HEX digits */
1034 }
1035
1036 return sprintf(buf, "%0*x\n", fmt_size, val);
1037}
1038
1039static ELANTS_VERSION_ATTR(fw_version);
1040static ELANTS_VERSION_ATTR(hw_version);
1041static ELANTS_VERSION_ATTR(test_version);
1042static ELANTS_VERSION_ATTR(solution_version);
1043static ELANTS_VERSION_ATTR(bc_version);
1044static ELANTS_VERSION_ATTR(iap_version);
1045
1046static struct attribute *elants_attributes[] = {
1047 &dev_attr_calibrate.attr,
1048 &dev_attr_update_fw.attr,
1049 &dev_attr_iap_mode.attr,
1050
1051 &elants_ver_attr_fw_version.dattr.attr,
1052 &elants_ver_attr_hw_version.dattr.attr,
1053 &elants_ver_attr_test_version.dattr.attr,
1054 &elants_ver_attr_solution_version.dattr.attr,
1055 &elants_ver_attr_bc_version.dattr.attr,
1056 &elants_ver_attr_iap_version.dattr.attr,
1057 NULL
1058};
1059
1060static struct attribute_group elants_attribute_group = {
1061 .attrs = elants_attributes,
1062};
1063
1064static void elants_i2c_remove_sysfs_group(void *_data)
1065{
1066 struct elants_data *ts = _data;
1067
1068 sysfs_remove_group(&ts->client->dev.kobj, &elants_attribute_group);
1069}
1070
1071static int elants_i2c_power_on(struct elants_data *ts)
1072{
1073 int error;
1074
1075 /*
1076 * If we do not have reset gpio assume platform firmware
1077 * controls regulators and does power them on for us.
1078 */
1079 if (IS_ERR_OR_NULL(ts->reset_gpio))
1080 return 0;
1081
1082 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1083
1084 error = regulator_enable(ts->vcc33);
1085 if (error) {
1086 dev_err(&ts->client->dev,
1087 "failed to enable vcc33 regulator: %d\n",
1088 error);
1089 goto release_reset_gpio;
1090 }
1091
1092 error = regulator_enable(ts->vccio);
1093 if (error) {
1094 dev_err(&ts->client->dev,
1095 "failed to enable vccio regulator: %d\n",
1096 error);
1097 regulator_disable(ts->vcc33);
1098 goto release_reset_gpio;
1099 }
1100
1101 /*
1102 * We need to wait a bit after powering on controller before
1103 * we are allowed to release reset GPIO.
1104 */
1105 udelay(ELAN_POWERON_DELAY_USEC);
1106
1107release_reset_gpio:
1108 gpiod_set_value_cansleep(ts->reset_gpio, 0);
1109 if (error)
1110 return error;
1111
1112 msleep(ELAN_RESET_DELAY_MSEC);
1113
1114 return 0;
1115}
1116
1117static void elants_i2c_power_off(void *_data)
1118{
1119 struct elants_data *ts = _data;
1120
1121 if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1122 /*
1123 * Activate reset gpio to prevent leakage through the
1124 * pin once we shut off power to the controller.
1125 */
1126 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1127 regulator_disable(ts->vccio);
1128 regulator_disable(ts->vcc33);
1129 }
1130}
1131
1132static int elants_i2c_probe(struct i2c_client *client,
1133 const struct i2c_device_id *id)
1134{
1135 union i2c_smbus_data dummy;
1136 struct elants_data *ts;
1137 unsigned long irqflags;
1138 int error;
1139
1140 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1141 dev_err(&client->dev,
1142 "%s: i2c check functionality error\n", DEVICE_NAME);
1143 return -ENXIO;
1144 }
1145
1146 ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1147 if (!ts)
1148 return -ENOMEM;
1149
1150 mutex_init(&ts->sysfs_mutex);
1151 init_completion(&ts->cmd_done);
1152
1153 ts->client = client;
1154 i2c_set_clientdata(client, ts);
1155
1156 ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1157 if (IS_ERR(ts->vcc33)) {
1158 error = PTR_ERR(ts->vcc33);
1159 if (error != -EPROBE_DEFER)
1160 dev_err(&client->dev,
1161 "Failed to get 'vcc33' regulator: %d\n",
1162 error);
1163 return error;
1164 }
1165
1166 ts->vccio = devm_regulator_get(&client->dev, "vccio");
1167 if (IS_ERR(ts->vccio)) {
1168 error = PTR_ERR(ts->vccio);
1169 if (error != -EPROBE_DEFER)
1170 dev_err(&client->dev,
1171 "Failed to get 'vccio' regulator: %d\n",
1172 error);
1173 return error;
1174 }
1175
1176 ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1177 if (IS_ERR(ts->reset_gpio)) {
1178 error = PTR_ERR(ts->reset_gpio);
1179
1180 if (error == -EPROBE_DEFER)
1181 return error;
1182
1183 if (error != -ENOENT && error != -ENOSYS) {
1184 dev_err(&client->dev,
1185 "failed to get reset gpio: %d\n",
1186 error);
1187 return error;
1188 }
1189
1190 ts->keep_power_in_suspend = true;
1191 }
1192
1193 error = elants_i2c_power_on(ts);
1194 if (error)
1195 return error;
1196
1197 error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1198 if (error) {
1199 dev_err(&client->dev,
1200 "failed to install power off action: %d\n", error);
1201 elants_i2c_power_off(ts);
1202 return error;
1203 }
1204
1205 /* Make sure there is something at this address */
1206 if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1207 I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1208 dev_err(&client->dev, "nothing at this address\n");
1209 return -ENXIO;
1210 }
1211
1212 error = elants_i2c_initialize(ts);
1213 if (error) {
1214 dev_err(&client->dev, "failed to initialize: %d\n", error);
1215 return error;
1216 }
1217
1218 ts->input = devm_input_allocate_device(&client->dev);
1219 if (!ts->input) {
1220 dev_err(&client->dev, "Failed to allocate input device\n");
1221 return -ENOMEM;
1222 }
1223
1224 ts->input->name = "Elan Touchscreen";
1225 ts->input->id.bustype = BUS_I2C;
1226
1227 __set_bit(BTN_TOUCH, ts->input->keybit);
1228 __set_bit(EV_ABS, ts->input->evbit);
1229 __set_bit(EV_KEY, ts->input->evbit);
1230
1231 /* Single touch input params setup */
1232 input_set_abs_params(ts->input, ABS_X, 0, ts->x_max, 0, 0);
1233 input_set_abs_params(ts->input, ABS_Y, 0, ts->y_max, 0, 0);
1234 input_set_abs_params(ts->input, ABS_PRESSURE, 0, 255, 0, 0);
1235 input_abs_set_res(ts->input, ABS_X, ts->x_res);
1236 input_abs_set_res(ts->input, ABS_Y, ts->y_res);
1237
1238 /* Multitouch input params setup */
1239 error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1240 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1241 if (error) {
1242 dev_err(&client->dev,
1243 "failed to initialize MT slots: %d\n", error);
1244 return error;
1245 }
1246
1247 input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1248 input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1249 input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1250 input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1251 input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1252 input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1253
1254 input_set_drvdata(ts->input, ts);
1255
1256 error = input_register_device(ts->input);
1257 if (error) {
1258 dev_err(&client->dev,
1259 "unable to register input device: %d\n", error);
1260 return error;
1261 }
1262
1263 /*
1264 * Systems using device tree should set up interrupt via DTS,
1265 * the rest will use the default falling edge interrupts.
1266 */
1267 irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
1268
1269 error = devm_request_threaded_irq(&client->dev, client->irq,
1270 NULL, elants_i2c_irq,
1271 irqflags | IRQF_ONESHOT,
1272 client->name, ts);
1273 if (error) {
1274 dev_err(&client->dev, "Failed to register interrupt\n");
1275 return error;
1276 }
1277
1278 /*
1279 * Systems using device tree should set up wakeup via DTS,
1280 * the rest will configure device as wakeup source by default.
1281 */
1282 if (!client->dev.of_node)
1283 device_init_wakeup(&client->dev, true);
1284
1285 error = sysfs_create_group(&client->dev.kobj, &elants_attribute_group);
1286 if (error) {
1287 dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1288 error);
1289 return error;
1290 }
1291
1292 error = devm_add_action(&client->dev,
1293 elants_i2c_remove_sysfs_group, ts);
1294 if (error) {
1295 elants_i2c_remove_sysfs_group(ts);
1296 dev_err(&client->dev,
1297 "Failed to add sysfs cleanup action: %d\n",
1298 error);
1299 return error;
1300 }
1301
1302 return 0;
1303}
1304
1305static int __maybe_unused elants_i2c_suspend(struct device *dev)
1306{
1307 struct i2c_client *client = to_i2c_client(dev);
1308 struct elants_data *ts = i2c_get_clientdata(client);
1309 const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
1310 int retry_cnt;
1311 int error;
1312
1313 /* Command not support in IAP recovery mode */
1314 if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1315 return -EBUSY;
1316
1317 disable_irq(client->irq);
1318
1319 if (device_may_wakeup(dev)) {
1320 /*
1321 * The device will automatically enter idle mode
1322 * that has reduced power consumption.
1323 */
1324 ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1325 } else if (ts->keep_power_in_suspend) {
1326 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1327 error = elants_i2c_send(client, set_sleep_cmd,
1328 sizeof(set_sleep_cmd));
1329 if (!error)
1330 break;
1331
1332 dev_err(&client->dev,
1333 "suspend command failed: %d\n", error);
1334 }
1335 } else {
1336 elants_i2c_power_off(ts);
1337 }
1338
1339 return 0;
1340}
1341
1342static int __maybe_unused elants_i2c_resume(struct device *dev)
1343{
1344 struct i2c_client *client = to_i2c_client(dev);
1345 struct elants_data *ts = i2c_get_clientdata(client);
1346 const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
1347 int retry_cnt;
1348 int error;
1349
1350 if (device_may_wakeup(dev)) {
1351 if (ts->wake_irq_enabled)
1352 disable_irq_wake(client->irq);
1353 elants_i2c_sw_reset(client);
1354 } else if (ts->keep_power_in_suspend) {
1355 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1356 error = elants_i2c_send(client, set_active_cmd,
1357 sizeof(set_active_cmd));
1358 if (!error)
1359 break;
1360
1361 dev_err(&client->dev,
1362 "resume command failed: %d\n", error);
1363 }
1364 } else {
1365 elants_i2c_power_on(ts);
1366 elants_i2c_initialize(ts);
1367 }
1368
1369 ts->state = ELAN_STATE_NORMAL;
1370 enable_irq(client->irq);
1371
1372 return 0;
1373}
1374
1375static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1376 elants_i2c_suspend, elants_i2c_resume);
1377
1378static const struct i2c_device_id elants_i2c_id[] = {
1379 { DEVICE_NAME, 0 },
1380 { }
1381};
1382MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1383
1384#ifdef CONFIG_ACPI
1385static const struct acpi_device_id elants_acpi_id[] = {
1386 { "ELAN0001", 0 },
1387 { }
1388};
1389MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1390#endif
1391
1392#ifdef CONFIG_OF
1393static const struct of_device_id elants_of_match[] = {
1394 { .compatible = "elan,ekth3500" },
1395 { /* sentinel */ }
1396};
1397MODULE_DEVICE_TABLE(of, elants_of_match);
1398#endif
1399
1400static struct i2c_driver elants_i2c_driver = {
1401 .probe = elants_i2c_probe,
1402 .id_table = elants_i2c_id,
1403 .driver = {
1404 .name = DEVICE_NAME,
1405 .pm = &elants_i2c_pm_ops,
1406 .acpi_match_table = ACPI_PTR(elants_acpi_id),
1407 .of_match_table = of_match_ptr(elants_of_match),
1408 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1409 },
1410};
1411module_i2c_driver(elants_i2c_driver);
1412
1413MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1414MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1415MODULE_VERSION(DRV_VERSION);
1416MODULE_LICENSE("GPL");
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/module.h>
23#include <linux/input.h>
24#include <linux/interrupt.h>
25#include <linux/irq.h>
26#include <linux/platform_device.h>
27#include <linux/async.h>
28#include <linux/i2c.h>
29#include <linux/delay.h>
30#include <linux/uaccess.h>
31#include <linux/buffer_head.h>
32#include <linux/slab.h>
33#include <linux/firmware.h>
34#include <linux/input/mt.h>
35#include <linux/acpi.h>
36#include <linux/of.h>
37#include <linux/gpio/consumer.h>
38#include <linux/regulator/consumer.h>
39#include <asm/unaligned.h>
40
41/* Device, Driver information */
42#define DEVICE_NAME "elants_i2c"
43
44/* Convert from rows or columns into resolution */
45#define ELAN_TS_RESOLUTION(n, m) (((n) - 1) * (m))
46
47/* FW header data */
48#define HEADER_SIZE 4
49#define FW_HDR_TYPE 0
50#define FW_HDR_COUNT 1
51#define FW_HDR_LENGTH 2
52
53/* Buffer mode Queue Header information */
54#define QUEUE_HEADER_SINGLE 0x62
55#define QUEUE_HEADER_NORMAL 0X63
56#define QUEUE_HEADER_WAIT 0x64
57
58/* Command header definition */
59#define CMD_HEADER_WRITE 0x54
60#define CMD_HEADER_READ 0x53
61#define CMD_HEADER_6B_READ 0x5B
62#define CMD_HEADER_RESP 0x52
63#define CMD_HEADER_6B_RESP 0x9B
64#define CMD_HEADER_HELLO 0x55
65#define CMD_HEADER_REK 0x66
66
67/* FW position data */
68#define PACKET_SIZE 55
69#define MAX_CONTACT_NUM 10
70#define FW_POS_HEADER 0
71#define FW_POS_STATE 1
72#define FW_POS_TOTAL 2
73#define FW_POS_XY 3
74#define FW_POS_CHECKSUM 34
75#define FW_POS_WIDTH 35
76#define FW_POS_PRESSURE 45
77
78#define HEADER_REPORT_10_FINGER 0x62
79
80/* Header (4 bytes) plus 3 fill 10-finger packets */
81#define MAX_PACKET_SIZE 169
82
83#define BOOT_TIME_DELAY_MS 50
84
85/* FW read command, 0x53 0x?? 0x0, 0x01 */
86#define E_ELAN_INFO_FW_VER 0x00
87#define E_ELAN_INFO_BC_VER 0x10
88#define E_ELAN_INFO_TEST_VER 0xE0
89#define E_ELAN_INFO_FW_ID 0xF0
90#define E_INFO_OSR 0xD6
91#define E_INFO_PHY_SCAN 0xD7
92#define E_INFO_PHY_DRIVER 0xD8
93
94#define MAX_RETRIES 3
95#define MAX_FW_UPDATE_RETRIES 30
96
97#define ELAN_FW_PAGESIZE 132
98
99/* calibration timeout definition */
100#define ELAN_CALI_TIMEOUT_MSEC 12000
101
102#define ELAN_POWERON_DELAY_USEC 500
103#define ELAN_RESET_DELAY_MSEC 20
104
105enum elants_state {
106 ELAN_STATE_NORMAL,
107 ELAN_WAIT_QUEUE_HEADER,
108 ELAN_WAIT_RECALIBRATION,
109};
110
111enum elants_iap_mode {
112 ELAN_IAP_OPERATIONAL,
113 ELAN_IAP_RECOVERY,
114};
115
116/* struct elants_data - represents state of Elan touchscreen device */
117struct elants_data {
118 struct i2c_client *client;
119 struct input_dev *input;
120
121 struct regulator *vcc33;
122 struct regulator *vccio;
123 struct gpio_desc *reset_gpio;
124
125 u16 fw_version;
126 u8 test_version;
127 u8 solution_version;
128 u8 bc_version;
129 u8 iap_version;
130 u16 hw_version;
131 unsigned int x_res; /* resolution in units/mm */
132 unsigned int y_res;
133 unsigned int x_max;
134 unsigned int y_max;
135
136 enum elants_state state;
137 enum elants_iap_mode iap_mode;
138
139 /* Guards against concurrent access to the device via sysfs */
140 struct mutex sysfs_mutex;
141
142 u8 cmd_resp[HEADER_SIZE];
143 struct completion cmd_done;
144
145 bool wake_irq_enabled;
146 bool keep_power_in_suspend;
147
148 /* Must be last to be used for DMA operations */
149 u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
150};
151
152static int elants_i2c_send(struct i2c_client *client,
153 const void *data, size_t size)
154{
155 int ret;
156
157 ret = i2c_master_send(client, data, size);
158 if (ret == size)
159 return 0;
160
161 if (ret >= 0)
162 ret = -EIO;
163
164 dev_err(&client->dev, "%s failed (%*ph): %d\n",
165 __func__, (int)size, data, ret);
166
167 return ret;
168}
169
170static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
171{
172 int ret;
173
174 ret = i2c_master_recv(client, data, size);
175 if (ret == size)
176 return 0;
177
178 if (ret >= 0)
179 ret = -EIO;
180
181 dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
182
183 return ret;
184}
185
186static int elants_i2c_execute_command(struct i2c_client *client,
187 const u8 *cmd, size_t cmd_size,
188 u8 *resp, size_t resp_size)
189{
190 struct i2c_msg msgs[2];
191 int ret;
192 u8 expected_response;
193
194 switch (cmd[0]) {
195 case CMD_HEADER_READ:
196 expected_response = CMD_HEADER_RESP;
197 break;
198
199 case CMD_HEADER_6B_READ:
200 expected_response = CMD_HEADER_6B_RESP;
201 break;
202
203 default:
204 dev_err(&client->dev, "%s: invalid command %*ph\n",
205 __func__, (int)cmd_size, cmd);
206 return -EINVAL;
207 }
208
209 msgs[0].addr = client->addr;
210 msgs[0].flags = client->flags & I2C_M_TEN;
211 msgs[0].len = cmd_size;
212 msgs[0].buf = (u8 *)cmd;
213
214 msgs[1].addr = client->addr;
215 msgs[1].flags = client->flags & I2C_M_TEN;
216 msgs[1].flags |= I2C_M_RD;
217 msgs[1].len = resp_size;
218 msgs[1].buf = resp;
219
220 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
221 if (ret < 0)
222 return ret;
223
224 if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
225 return -EIO;
226
227 return 0;
228}
229
230static int elants_i2c_calibrate(struct elants_data *ts)
231{
232 struct i2c_client *client = ts->client;
233 int ret, error;
234 static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
235 static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
236 static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
237
238 disable_irq(client->irq);
239
240 ts->state = ELAN_WAIT_RECALIBRATION;
241 reinit_completion(&ts->cmd_done);
242
243 elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
244 elants_i2c_send(client, rek, sizeof(rek));
245
246 enable_irq(client->irq);
247
248 ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
249 msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
250
251 ts->state = ELAN_STATE_NORMAL;
252
253 if (ret <= 0) {
254 error = ret < 0 ? ret : -ETIMEDOUT;
255 dev_err(&client->dev,
256 "error while waiting for calibration to complete: %d\n",
257 error);
258 return error;
259 }
260
261 if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
262 dev_err(&client->dev,
263 "unexpected calibration response: %*ph\n",
264 (int)sizeof(ts->cmd_resp), ts->cmd_resp);
265 return -EINVAL;
266 }
267
268 return 0;
269}
270
271static int elants_i2c_sw_reset(struct i2c_client *client)
272{
273 const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
274 int error;
275
276 error = elants_i2c_send(client, soft_rst_cmd,
277 sizeof(soft_rst_cmd));
278 if (error) {
279 dev_err(&client->dev, "software reset failed: %d\n", error);
280 return error;
281 }
282
283 /*
284 * We should wait at least 10 msec (but no more than 40) before
285 * sending fastboot or IAP command to the device.
286 */
287 msleep(30);
288
289 return 0;
290}
291
292static u16 elants_i2c_parse_version(u8 *buf)
293{
294 return get_unaligned_be32(buf) >> 4;
295}
296
297static int elants_i2c_query_hw_version(struct elants_data *ts)
298{
299 struct i2c_client *client = ts->client;
300 int error, retry_cnt;
301 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
302 u8 resp[HEADER_SIZE];
303
304 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
305 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
306 resp, sizeof(resp));
307 if (!error) {
308 ts->hw_version = elants_i2c_parse_version(resp);
309 if (ts->hw_version != 0xffff)
310 return 0;
311 }
312
313 dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
314 error, (int)sizeof(resp), resp);
315 }
316
317 if (error) {
318 dev_err(&client->dev,
319 "Failed to read fw id: %d\n", error);
320 return error;
321 }
322
323 dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
324
325 return -EINVAL;
326}
327
328static int elants_i2c_query_fw_version(struct elants_data *ts)
329{
330 struct i2c_client *client = ts->client;
331 int error, retry_cnt;
332 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
333 u8 resp[HEADER_SIZE];
334
335 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
336 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
337 resp, sizeof(resp));
338 if (!error) {
339 ts->fw_version = elants_i2c_parse_version(resp);
340 if (ts->fw_version != 0x0000 &&
341 ts->fw_version != 0xffff)
342 return 0;
343 }
344
345 dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
346 error, (int)sizeof(resp), resp);
347 }
348
349 dev_err(&client->dev,
350 "Failed to read fw version or fw version is invalid\n");
351
352 return -EINVAL;
353}
354
355static int elants_i2c_query_test_version(struct elants_data *ts)
356{
357 struct i2c_client *client = ts->client;
358 int error, retry_cnt;
359 u16 version;
360 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
361 u8 resp[HEADER_SIZE];
362
363 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
364 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
365 resp, sizeof(resp));
366 if (!error) {
367 version = elants_i2c_parse_version(resp);
368 ts->test_version = version >> 8;
369 ts->solution_version = version & 0xff;
370
371 return 0;
372 }
373
374 dev_dbg(&client->dev,
375 "read test version error rc=%d, buf=%*phC\n",
376 error, (int)sizeof(resp), resp);
377 }
378
379 dev_err(&client->dev, "Failed to read test version\n");
380
381 return -EINVAL;
382}
383
384static int elants_i2c_query_bc_version(struct elants_data *ts)
385{
386 struct i2c_client *client = ts->client;
387 const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
388 u8 resp[HEADER_SIZE];
389 u16 version;
390 int error;
391
392 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
393 resp, sizeof(resp));
394 if (error) {
395 dev_err(&client->dev,
396 "read BC version error=%d, buf=%*phC\n",
397 error, (int)sizeof(resp), resp);
398 return error;
399 }
400
401 version = elants_i2c_parse_version(resp);
402 ts->bc_version = version >> 8;
403 ts->iap_version = version & 0xff;
404
405 return 0;
406}
407
408static int elants_i2c_query_ts_info(struct elants_data *ts)
409{
410 struct i2c_client *client = ts->client;
411 int error;
412 u8 resp[17];
413 u16 phy_x, phy_y, rows, cols, osr;
414 const u8 get_resolution_cmd[] = {
415 CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
416 };
417 const u8 get_osr_cmd[] = {
418 CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
419 };
420 const u8 get_physical_scan_cmd[] = {
421 CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
422 };
423 const u8 get_physical_drive_cmd[] = {
424 CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
425 };
426
427 /* Get trace number */
428 error = elants_i2c_execute_command(client,
429 get_resolution_cmd,
430 sizeof(get_resolution_cmd),
431 resp, sizeof(resp));
432 if (error) {
433 dev_err(&client->dev, "get resolution command failed: %d\n",
434 error);
435 return error;
436 }
437
438 rows = resp[2] + resp[6] + resp[10];
439 cols = resp[3] + resp[7] + resp[11];
440
441 /* Process mm_to_pixel information */
442 error = elants_i2c_execute_command(client,
443 get_osr_cmd, sizeof(get_osr_cmd),
444 resp, sizeof(resp));
445 if (error) {
446 dev_err(&client->dev, "get osr command failed: %d\n",
447 error);
448 return error;
449 }
450
451 osr = resp[3];
452
453 error = elants_i2c_execute_command(client,
454 get_physical_scan_cmd,
455 sizeof(get_physical_scan_cmd),
456 resp, sizeof(resp));
457 if (error) {
458 dev_err(&client->dev, "get physical scan command failed: %d\n",
459 error);
460 return error;
461 }
462
463 phy_x = get_unaligned_be16(&resp[2]);
464
465 error = elants_i2c_execute_command(client,
466 get_physical_drive_cmd,
467 sizeof(get_physical_drive_cmd),
468 resp, sizeof(resp));
469 if (error) {
470 dev_err(&client->dev, "get physical drive command failed: %d\n",
471 error);
472 return error;
473 }
474
475 phy_y = get_unaligned_be16(&resp[2]);
476
477 dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
478
479 if (rows == 0 || cols == 0 || osr == 0) {
480 dev_warn(&client->dev,
481 "invalid trace number data: %d, %d, %d\n",
482 rows, cols, osr);
483 } else {
484 /* translate trace number to TS resolution */
485 ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
486 ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
487 ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
488 ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
489 }
490
491 return 0;
492}
493
494static int elants_i2c_fastboot(struct i2c_client *client)
495{
496 const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
497 int error;
498
499 error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
500 if (error) {
501 dev_err(&client->dev, "boot failed: %d\n", error);
502 return error;
503 }
504
505 dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
506 return 0;
507}
508
509static int elants_i2c_initialize(struct elants_data *ts)
510{
511 struct i2c_client *client = ts->client;
512 int error, error2, retry_cnt;
513 const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
514 const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
515 u8 buf[HEADER_SIZE];
516
517 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
518 error = elants_i2c_sw_reset(client);
519 if (error) {
520 /* Continue initializing if it's the last try */
521 if (retry_cnt < MAX_RETRIES - 1)
522 continue;
523 }
524
525 error = elants_i2c_fastboot(client);
526 if (error) {
527 /* Continue initializing if it's the last try */
528 if (retry_cnt < MAX_RETRIES - 1)
529 continue;
530 }
531
532 /* Wait for Hello packet */
533 msleep(BOOT_TIME_DELAY_MS);
534
535 error = elants_i2c_read(client, buf, sizeof(buf));
536 if (error) {
537 dev_err(&client->dev,
538 "failed to read 'hello' packet: %d\n", error);
539 } else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
540 ts->iap_mode = ELAN_IAP_OPERATIONAL;
541 break;
542 } else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
543 /*
544 * Setting error code will mark device
545 * in recovery mode below.
546 */
547 error = -EIO;
548 break;
549 } else {
550 error = -EINVAL;
551 dev_err(&client->dev,
552 "invalid 'hello' packet: %*ph\n",
553 (int)sizeof(buf), buf);
554 }
555 }
556
557 /* hw version is available even if device in recovery state */
558 error2 = elants_i2c_query_hw_version(ts);
559 if (!error)
560 error = error2;
561
562 if (!error)
563 error = elants_i2c_query_fw_version(ts);
564 if (!error)
565 error = elants_i2c_query_test_version(ts);
566 if (!error)
567 error = elants_i2c_query_bc_version(ts);
568 if (!error)
569 error = elants_i2c_query_ts_info(ts);
570
571 if (error)
572 ts->iap_mode = ELAN_IAP_RECOVERY;
573
574 return 0;
575}
576
577/*
578 * Firmware update interface.
579 */
580
581static int elants_i2c_fw_write_page(struct i2c_client *client,
582 const void *page)
583{
584 const u8 ack_ok[] = { 0xaa, 0xaa };
585 u8 buf[2];
586 int retry;
587 int error;
588
589 for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
590 error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
591 if (error) {
592 dev_err(&client->dev,
593 "IAP Write Page failed: %d\n", error);
594 continue;
595 }
596
597 error = elants_i2c_read(client, buf, 2);
598 if (error) {
599 dev_err(&client->dev,
600 "IAP Ack read failed: %d\n", error);
601 return error;
602 }
603
604 if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
605 return 0;
606
607 error = -EIO;
608 dev_err(&client->dev,
609 "IAP Get Ack Error [%02x:%02x]\n",
610 buf[0], buf[1]);
611 }
612
613 return error;
614}
615
616static int elants_i2c_do_update_firmware(struct i2c_client *client,
617 const struct firmware *fw,
618 bool force)
619{
620 const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
621 const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
622 const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
623 const u8 close_idle[] = {0x54, 0x2c, 0x01, 0x01};
624 u8 buf[HEADER_SIZE];
625 u16 send_id;
626 int page, n_fw_pages;
627 int error;
628
629 /* Recovery mode detection! */
630 if (force) {
631 dev_dbg(&client->dev, "Recovery mode procedure\n");
632 error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
633 } else {
634 /* Start IAP Procedure */
635 dev_dbg(&client->dev, "Normal IAP procedure\n");
636 /* Close idle mode */
637 error = elants_i2c_send(client, close_idle, sizeof(close_idle));
638 if (error)
639 dev_err(&client->dev, "Failed close idle: %d\n", error);
640 msleep(60);
641 elants_i2c_sw_reset(client);
642 msleep(20);
643 error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
644 }
645
646 if (error) {
647 dev_err(&client->dev, "failed to enter IAP mode: %d\n", error);
648 return error;
649 }
650
651 msleep(20);
652
653 /* check IAP state */
654 error = elants_i2c_read(client, buf, 4);
655 if (error) {
656 dev_err(&client->dev,
657 "failed to read IAP acknowledgement: %d\n",
658 error);
659 return error;
660 }
661
662 if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
663 dev_err(&client->dev,
664 "failed to enter IAP: %*ph (expected %*ph)\n",
665 (int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
666 return -EIO;
667 }
668
669 dev_info(&client->dev, "successfully entered IAP mode");
670
671 send_id = client->addr;
672 error = elants_i2c_send(client, &send_id, 1);
673 if (error) {
674 dev_err(&client->dev, "sending dummy byte failed: %d\n",
675 error);
676 return error;
677 }
678
679 /* Clear the last page of Master */
680 error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
681 if (error) {
682 dev_err(&client->dev, "clearing of the last page failed: %d\n",
683 error);
684 return error;
685 }
686
687 error = elants_i2c_read(client, buf, 2);
688 if (error) {
689 dev_err(&client->dev,
690 "failed to read ACK for clearing the last page: %d\n",
691 error);
692 return error;
693 }
694
695 n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
696 dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
697
698 for (page = 0; page < n_fw_pages; page++) {
699 error = elants_i2c_fw_write_page(client,
700 fw->data + page * ELAN_FW_PAGESIZE);
701 if (error) {
702 dev_err(&client->dev,
703 "failed to write FW page %d: %d\n",
704 page, error);
705 return error;
706 }
707 }
708
709 /* Old iap needs to wait 200ms for WDT and rest is for hello packets */
710 msleep(300);
711
712 dev_info(&client->dev, "firmware update completed\n");
713 return 0;
714}
715
716static int elants_i2c_fw_update(struct elants_data *ts)
717{
718 struct i2c_client *client = ts->client;
719 const struct firmware *fw;
720 char *fw_name;
721 int error;
722
723 fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
724 if (!fw_name)
725 return -ENOMEM;
726
727 dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
728 error = request_firmware(&fw, fw_name, &client->dev);
729 kfree(fw_name);
730 if (error) {
731 dev_err(&client->dev, "failed to request firmware: %d\n",
732 error);
733 return error;
734 }
735
736 if (fw->size % ELAN_FW_PAGESIZE) {
737 dev_err(&client->dev, "invalid firmware length: %zu\n",
738 fw->size);
739 error = -EINVAL;
740 goto out;
741 }
742
743 disable_irq(client->irq);
744
745 error = elants_i2c_do_update_firmware(client, fw,
746 ts->iap_mode == ELAN_IAP_RECOVERY);
747 if (error) {
748 dev_err(&client->dev, "firmware update failed: %d\n", error);
749 ts->iap_mode = ELAN_IAP_RECOVERY;
750 goto out_enable_irq;
751 }
752
753 error = elants_i2c_initialize(ts);
754 if (error) {
755 dev_err(&client->dev,
756 "failed to initialize device after firmware update: %d\n",
757 error);
758 ts->iap_mode = ELAN_IAP_RECOVERY;
759 goto out_enable_irq;
760 }
761
762 ts->iap_mode = ELAN_IAP_OPERATIONAL;
763
764out_enable_irq:
765 ts->state = ELAN_STATE_NORMAL;
766 enable_irq(client->irq);
767 msleep(100);
768
769 if (!error)
770 elants_i2c_calibrate(ts);
771out:
772 release_firmware(fw);
773 return error;
774}
775
776/*
777 * Event reporting.
778 */
779
780static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
781{
782 struct input_dev *input = ts->input;
783 unsigned int n_fingers;
784 u16 finger_state;
785 int i;
786
787 n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
788 finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
789 buf[FW_POS_STATE];
790
791 dev_dbg(&ts->client->dev,
792 "n_fingers: %u, state: %04x\n", n_fingers, finger_state);
793
794 for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
795 if (finger_state & 1) {
796 unsigned int x, y, p, w;
797 u8 *pos;
798
799 pos = &buf[FW_POS_XY + i * 3];
800 x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
801 y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
802 p = buf[FW_POS_PRESSURE + i];
803 w = buf[FW_POS_WIDTH + i];
804
805 dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
806 i, x, y, p, w);
807
808 input_mt_slot(input, i);
809 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
810 input_event(input, EV_ABS, ABS_MT_POSITION_X, x);
811 input_event(input, EV_ABS, ABS_MT_POSITION_Y, y);
812 input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
813 input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
814
815 n_fingers--;
816 }
817
818 finger_state >>= 1;
819 }
820
821 input_mt_sync_frame(input);
822 input_sync(input);
823}
824
825static u8 elants_i2c_calculate_checksum(u8 *buf)
826{
827 u8 checksum = 0;
828 u8 i;
829
830 for (i = 0; i < FW_POS_CHECKSUM; i++)
831 checksum += buf[i];
832
833 return checksum;
834}
835
836static void elants_i2c_event(struct elants_data *ts, u8 *buf)
837{
838 u8 checksum = elants_i2c_calculate_checksum(buf);
839
840 if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
841 dev_warn(&ts->client->dev,
842 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
843 __func__, buf[FW_POS_HEADER],
844 checksum, buf[FW_POS_CHECKSUM]);
845 else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
846 dev_warn(&ts->client->dev,
847 "%s: unknown packet type: %02x\n",
848 __func__, buf[FW_POS_HEADER]);
849 else
850 elants_i2c_mt_event(ts, buf);
851}
852
853static irqreturn_t elants_i2c_irq(int irq, void *_dev)
854{
855 const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
856 struct elants_data *ts = _dev;
857 struct i2c_client *client = ts->client;
858 int report_count, report_len;
859 int i;
860 int len;
861
862 len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
863 if (len < 0) {
864 dev_err(&client->dev, "%s: failed to read data: %d\n",
865 __func__, len);
866 goto out;
867 }
868
869 dev_dbg(&client->dev, "%s: packet %*ph\n",
870 __func__, HEADER_SIZE, ts->buf);
871
872 switch (ts->state) {
873 case ELAN_WAIT_RECALIBRATION:
874 if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
875 memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
876 complete(&ts->cmd_done);
877 ts->state = ELAN_STATE_NORMAL;
878 }
879 break;
880
881 case ELAN_WAIT_QUEUE_HEADER:
882 if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
883 break;
884
885 ts->state = ELAN_STATE_NORMAL;
886 /* fall through */
887
888 case ELAN_STATE_NORMAL:
889
890 switch (ts->buf[FW_HDR_TYPE]) {
891 case CMD_HEADER_HELLO:
892 case CMD_HEADER_RESP:
893 case CMD_HEADER_REK:
894 break;
895
896 case QUEUE_HEADER_WAIT:
897 if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
898 dev_err(&client->dev,
899 "invalid wait packet %*ph\n",
900 HEADER_SIZE, ts->buf);
901 } else {
902 ts->state = ELAN_WAIT_QUEUE_HEADER;
903 udelay(30);
904 }
905 break;
906
907 case QUEUE_HEADER_SINGLE:
908 elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
909 break;
910
911 case QUEUE_HEADER_NORMAL:
912 report_count = ts->buf[FW_HDR_COUNT];
913 if (report_count == 0 || report_count > 3) {
914 dev_err(&client->dev,
915 "bad report count: %*ph\n",
916 HEADER_SIZE, ts->buf);
917 break;
918 }
919
920 report_len = ts->buf[FW_HDR_LENGTH] / report_count;
921 if (report_len != PACKET_SIZE) {
922 dev_err(&client->dev,
923 "mismatching report length: %*ph\n",
924 HEADER_SIZE, ts->buf);
925 break;
926 }
927
928 for (i = 0; i < report_count; i++) {
929 u8 *buf = ts->buf + HEADER_SIZE +
930 i * PACKET_SIZE;
931 elants_i2c_event(ts, buf);
932 }
933 break;
934
935 default:
936 dev_err(&client->dev, "unknown packet %*ph\n",
937 HEADER_SIZE, ts->buf);
938 break;
939 }
940 break;
941 }
942
943out:
944 return IRQ_HANDLED;
945}
946
947/*
948 * sysfs interface
949 */
950static ssize_t calibrate_store(struct device *dev,
951 struct device_attribute *attr,
952 const char *buf, size_t count)
953{
954 struct i2c_client *client = to_i2c_client(dev);
955 struct elants_data *ts = i2c_get_clientdata(client);
956 int error;
957
958 error = mutex_lock_interruptible(&ts->sysfs_mutex);
959 if (error)
960 return error;
961
962 error = elants_i2c_calibrate(ts);
963
964 mutex_unlock(&ts->sysfs_mutex);
965 return error ?: count;
966}
967
968static ssize_t write_update_fw(struct device *dev,
969 struct device_attribute *attr,
970 const char *buf, size_t count)
971{
972 struct i2c_client *client = to_i2c_client(dev);
973 struct elants_data *ts = i2c_get_clientdata(client);
974 int error;
975
976 error = mutex_lock_interruptible(&ts->sysfs_mutex);
977 if (error)
978 return error;
979
980 error = elants_i2c_fw_update(ts);
981 dev_dbg(dev, "firmware update result: %d\n", error);
982
983 mutex_unlock(&ts->sysfs_mutex);
984 return error ?: count;
985}
986
987static ssize_t show_iap_mode(struct device *dev,
988 struct device_attribute *attr, char *buf)
989{
990 struct i2c_client *client = to_i2c_client(dev);
991 struct elants_data *ts = i2c_get_clientdata(client);
992
993 return sprintf(buf, "%s\n",
994 ts->iap_mode == ELAN_IAP_OPERATIONAL ?
995 "Normal" : "Recovery");
996}
997
998static DEVICE_ATTR_WO(calibrate);
999static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1000static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1001
1002struct elants_version_attribute {
1003 struct device_attribute dattr;
1004 size_t field_offset;
1005 size_t field_size;
1006};
1007
1008#define __ELANTS_FIELD_SIZE(_field) \
1009 sizeof(((struct elants_data *)NULL)->_field)
1010#define __ELANTS_VERIFY_SIZE(_field) \
1011 (BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) + \
1012 __ELANTS_FIELD_SIZE(_field))
1013#define ELANTS_VERSION_ATTR(_field) \
1014 struct elants_version_attribute elants_ver_attr_##_field = { \
1015 .dattr = __ATTR(_field, S_IRUGO, \
1016 elants_version_attribute_show, NULL), \
1017 .field_offset = offsetof(struct elants_data, _field), \
1018 .field_size = __ELANTS_VERIFY_SIZE(_field), \
1019 }
1020
1021static ssize_t elants_version_attribute_show(struct device *dev,
1022 struct device_attribute *dattr,
1023 char *buf)
1024{
1025 struct i2c_client *client = to_i2c_client(dev);
1026 struct elants_data *ts = i2c_get_clientdata(client);
1027 struct elants_version_attribute *attr =
1028 container_of(dattr, struct elants_version_attribute, dattr);
1029 u8 *field = (u8 *)((char *)ts + attr->field_offset);
1030 unsigned int fmt_size;
1031 unsigned int val;
1032
1033 if (attr->field_size == 1) {
1034 val = *field;
1035 fmt_size = 2; /* 2 HEX digits */
1036 } else {
1037 val = *(u16 *)field;
1038 fmt_size = 4; /* 4 HEX digits */
1039 }
1040
1041 return sprintf(buf, "%0*x\n", fmt_size, val);
1042}
1043
1044static ELANTS_VERSION_ATTR(fw_version);
1045static ELANTS_VERSION_ATTR(hw_version);
1046static ELANTS_VERSION_ATTR(test_version);
1047static ELANTS_VERSION_ATTR(solution_version);
1048static ELANTS_VERSION_ATTR(bc_version);
1049static ELANTS_VERSION_ATTR(iap_version);
1050
1051static struct attribute *elants_attributes[] = {
1052 &dev_attr_calibrate.attr,
1053 &dev_attr_update_fw.attr,
1054 &dev_attr_iap_mode.attr,
1055
1056 &elants_ver_attr_fw_version.dattr.attr,
1057 &elants_ver_attr_hw_version.dattr.attr,
1058 &elants_ver_attr_test_version.dattr.attr,
1059 &elants_ver_attr_solution_version.dattr.attr,
1060 &elants_ver_attr_bc_version.dattr.attr,
1061 &elants_ver_attr_iap_version.dattr.attr,
1062 NULL
1063};
1064
1065static const struct attribute_group elants_attribute_group = {
1066 .attrs = elants_attributes,
1067};
1068
1069static int elants_i2c_power_on(struct elants_data *ts)
1070{
1071 int error;
1072
1073 /*
1074 * If we do not have reset gpio assume platform firmware
1075 * controls regulators and does power them on for us.
1076 */
1077 if (IS_ERR_OR_NULL(ts->reset_gpio))
1078 return 0;
1079
1080 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1081
1082 error = regulator_enable(ts->vcc33);
1083 if (error) {
1084 dev_err(&ts->client->dev,
1085 "failed to enable vcc33 regulator: %d\n",
1086 error);
1087 goto release_reset_gpio;
1088 }
1089
1090 error = regulator_enable(ts->vccio);
1091 if (error) {
1092 dev_err(&ts->client->dev,
1093 "failed to enable vccio regulator: %d\n",
1094 error);
1095 regulator_disable(ts->vcc33);
1096 goto release_reset_gpio;
1097 }
1098
1099 /*
1100 * We need to wait a bit after powering on controller before
1101 * we are allowed to release reset GPIO.
1102 */
1103 udelay(ELAN_POWERON_DELAY_USEC);
1104
1105release_reset_gpio:
1106 gpiod_set_value_cansleep(ts->reset_gpio, 0);
1107 if (error)
1108 return error;
1109
1110 msleep(ELAN_RESET_DELAY_MSEC);
1111
1112 return 0;
1113}
1114
1115static void elants_i2c_power_off(void *_data)
1116{
1117 struct elants_data *ts = _data;
1118
1119 if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1120 /*
1121 * Activate reset gpio to prevent leakage through the
1122 * pin once we shut off power to the controller.
1123 */
1124 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1125 regulator_disable(ts->vccio);
1126 regulator_disable(ts->vcc33);
1127 }
1128}
1129
1130static int elants_i2c_probe(struct i2c_client *client,
1131 const struct i2c_device_id *id)
1132{
1133 union i2c_smbus_data dummy;
1134 struct elants_data *ts;
1135 unsigned long irqflags;
1136 int error;
1137
1138 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1139 dev_err(&client->dev,
1140 "%s: i2c check functionality error\n", DEVICE_NAME);
1141 return -ENXIO;
1142 }
1143
1144 ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1145 if (!ts)
1146 return -ENOMEM;
1147
1148 mutex_init(&ts->sysfs_mutex);
1149 init_completion(&ts->cmd_done);
1150
1151 ts->client = client;
1152 i2c_set_clientdata(client, ts);
1153
1154 ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1155 if (IS_ERR(ts->vcc33)) {
1156 error = PTR_ERR(ts->vcc33);
1157 if (error != -EPROBE_DEFER)
1158 dev_err(&client->dev,
1159 "Failed to get 'vcc33' regulator: %d\n",
1160 error);
1161 return error;
1162 }
1163
1164 ts->vccio = devm_regulator_get(&client->dev, "vccio");
1165 if (IS_ERR(ts->vccio)) {
1166 error = PTR_ERR(ts->vccio);
1167 if (error != -EPROBE_DEFER)
1168 dev_err(&client->dev,
1169 "Failed to get 'vccio' regulator: %d\n",
1170 error);
1171 return error;
1172 }
1173
1174 ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1175 if (IS_ERR(ts->reset_gpio)) {
1176 error = PTR_ERR(ts->reset_gpio);
1177
1178 if (error == -EPROBE_DEFER)
1179 return error;
1180
1181 if (error != -ENOENT && error != -ENOSYS) {
1182 dev_err(&client->dev,
1183 "failed to get reset gpio: %d\n",
1184 error);
1185 return error;
1186 }
1187
1188 ts->keep_power_in_suspend = true;
1189 }
1190
1191 error = elants_i2c_power_on(ts);
1192 if (error)
1193 return error;
1194
1195 error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1196 if (error) {
1197 dev_err(&client->dev,
1198 "failed to install power off action: %d\n", error);
1199 elants_i2c_power_off(ts);
1200 return error;
1201 }
1202
1203 /* Make sure there is something at this address */
1204 if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1205 I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1206 dev_err(&client->dev, "nothing at this address\n");
1207 return -ENXIO;
1208 }
1209
1210 error = elants_i2c_initialize(ts);
1211 if (error) {
1212 dev_err(&client->dev, "failed to initialize: %d\n", error);
1213 return error;
1214 }
1215
1216 ts->input = devm_input_allocate_device(&client->dev);
1217 if (!ts->input) {
1218 dev_err(&client->dev, "Failed to allocate input device\n");
1219 return -ENOMEM;
1220 }
1221
1222 ts->input->name = "Elan Touchscreen";
1223 ts->input->id.bustype = BUS_I2C;
1224
1225 __set_bit(BTN_TOUCH, ts->input->keybit);
1226 __set_bit(EV_ABS, ts->input->evbit);
1227 __set_bit(EV_KEY, ts->input->evbit);
1228
1229 /* Single touch input params setup */
1230 input_set_abs_params(ts->input, ABS_X, 0, ts->x_max, 0, 0);
1231 input_set_abs_params(ts->input, ABS_Y, 0, ts->y_max, 0, 0);
1232 input_set_abs_params(ts->input, ABS_PRESSURE, 0, 255, 0, 0);
1233 input_abs_set_res(ts->input, ABS_X, ts->x_res);
1234 input_abs_set_res(ts->input, ABS_Y, ts->y_res);
1235
1236 /* Multitouch input params setup */
1237 error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1238 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1239 if (error) {
1240 dev_err(&client->dev,
1241 "failed to initialize MT slots: %d\n", error);
1242 return error;
1243 }
1244
1245 input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1246 input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1247 input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1248 input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1249 input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1250 input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1251
1252 error = input_register_device(ts->input);
1253 if (error) {
1254 dev_err(&client->dev,
1255 "unable to register input device: %d\n", error);
1256 return error;
1257 }
1258
1259 /*
1260 * Platform code (ACPI, DTS) should normally set up interrupt
1261 * for us, but in case it did not let's fall back to using falling
1262 * edge to be compatible with older Chromebooks.
1263 */
1264 irqflags = irq_get_trigger_type(client->irq);
1265 if (!irqflags)
1266 irqflags = IRQF_TRIGGER_FALLING;
1267
1268 error = devm_request_threaded_irq(&client->dev, client->irq,
1269 NULL, elants_i2c_irq,
1270 irqflags | IRQF_ONESHOT,
1271 client->name, ts);
1272 if (error) {
1273 dev_err(&client->dev, "Failed to register interrupt\n");
1274 return error;
1275 }
1276
1277 /*
1278 * Systems using device tree should set up wakeup via DTS,
1279 * the rest will configure device as wakeup source by default.
1280 */
1281 if (!client->dev.of_node)
1282 device_init_wakeup(&client->dev, true);
1283
1284 error = devm_device_add_group(&client->dev, &elants_attribute_group);
1285 if (error) {
1286 dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1287 error);
1288 return error;
1289 }
1290
1291 return 0;
1292}
1293
1294static int __maybe_unused elants_i2c_suspend(struct device *dev)
1295{
1296 struct i2c_client *client = to_i2c_client(dev);
1297 struct elants_data *ts = i2c_get_clientdata(client);
1298 const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
1299 int retry_cnt;
1300 int error;
1301
1302 /* Command not support in IAP recovery mode */
1303 if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1304 return -EBUSY;
1305
1306 disable_irq(client->irq);
1307
1308 if (device_may_wakeup(dev)) {
1309 /*
1310 * The device will automatically enter idle mode
1311 * that has reduced power consumption.
1312 */
1313 ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1314 } else if (ts->keep_power_in_suspend) {
1315 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1316 error = elants_i2c_send(client, set_sleep_cmd,
1317 sizeof(set_sleep_cmd));
1318 if (!error)
1319 break;
1320
1321 dev_err(&client->dev,
1322 "suspend command failed: %d\n", error);
1323 }
1324 } else {
1325 elants_i2c_power_off(ts);
1326 }
1327
1328 return 0;
1329}
1330
1331static int __maybe_unused elants_i2c_resume(struct device *dev)
1332{
1333 struct i2c_client *client = to_i2c_client(dev);
1334 struct elants_data *ts = i2c_get_clientdata(client);
1335 const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
1336 int retry_cnt;
1337 int error;
1338
1339 if (device_may_wakeup(dev)) {
1340 if (ts->wake_irq_enabled)
1341 disable_irq_wake(client->irq);
1342 elants_i2c_sw_reset(client);
1343 } else if (ts->keep_power_in_suspend) {
1344 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1345 error = elants_i2c_send(client, set_active_cmd,
1346 sizeof(set_active_cmd));
1347 if (!error)
1348 break;
1349
1350 dev_err(&client->dev,
1351 "resume command failed: %d\n", error);
1352 }
1353 } else {
1354 elants_i2c_power_on(ts);
1355 elants_i2c_initialize(ts);
1356 }
1357
1358 ts->state = ELAN_STATE_NORMAL;
1359 enable_irq(client->irq);
1360
1361 return 0;
1362}
1363
1364static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1365 elants_i2c_suspend, elants_i2c_resume);
1366
1367static const struct i2c_device_id elants_i2c_id[] = {
1368 { DEVICE_NAME, 0 },
1369 { }
1370};
1371MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1372
1373#ifdef CONFIG_ACPI
1374static const struct acpi_device_id elants_acpi_id[] = {
1375 { "ELAN0001", 0 },
1376 { }
1377};
1378MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1379#endif
1380
1381#ifdef CONFIG_OF
1382static const struct of_device_id elants_of_match[] = {
1383 { .compatible = "elan,ekth3500" },
1384 { /* sentinel */ }
1385};
1386MODULE_DEVICE_TABLE(of, elants_of_match);
1387#endif
1388
1389static struct i2c_driver elants_i2c_driver = {
1390 .probe = elants_i2c_probe,
1391 .id_table = elants_i2c_id,
1392 .driver = {
1393 .name = DEVICE_NAME,
1394 .pm = &elants_i2c_pm_ops,
1395 .acpi_match_table = ACPI_PTR(elants_acpi_id),
1396 .of_match_table = of_match_ptr(elants_of_match),
1397 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1398 },
1399};
1400module_i2c_driver(elants_i2c_driver);
1401
1402MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1403MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1404MODULE_LICENSE("GPL");