treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / input / touchscreen / elants_i2c.c
blobd4ad24ea54c8ce2a9a8794308423667dd8add8bf
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Elan Microelectronics touch panels with I2C interface
5 * Copyright (C) 2014 Elan Microelectronics Corporation.
6 * Scott Liu <scott.liu@emc.com.tw>
8 * This code is partly based on hid-multitouch.c:
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
14 * This code is partly based on i2c-hid.c:
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
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>
41 /* Device, Driver information */
42 #define DEVICE_NAME "elants_i2c"
44 /* Convert from rows or columns into resolution */
45 #define ELAN_TS_RESOLUTION(n, m) (((n) - 1) * (m))
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
53 /* Buffer mode Queue Header information */
54 #define QUEUE_HEADER_SINGLE 0x62
55 #define QUEUE_HEADER_NORMAL 0X63
56 #define QUEUE_HEADER_WAIT 0x64
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
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
78 #define HEADER_REPORT_10_FINGER 0x62
80 /* Header (4 bytes) plus 3 fill 10-finger packets */
81 #define MAX_PACKET_SIZE 169
83 #define BOOT_TIME_DELAY_MS 50
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
94 #define MAX_RETRIES 3
95 #define MAX_FW_UPDATE_RETRIES 30
97 #define ELAN_FW_PAGESIZE 132
99 /* calibration timeout definition */
100 #define ELAN_CALI_TIMEOUT_MSEC 12000
102 #define ELAN_POWERON_DELAY_USEC 500
103 #define ELAN_RESET_DELAY_MSEC 20
105 enum elants_state {
106 ELAN_STATE_NORMAL,
107 ELAN_WAIT_QUEUE_HEADER,
108 ELAN_WAIT_RECALIBRATION,
111 enum elants_iap_mode {
112 ELAN_IAP_OPERATIONAL,
113 ELAN_IAP_RECOVERY,
116 /* struct elants_data - represents state of Elan touchscreen device */
117 struct elants_data {
118 struct i2c_client *client;
119 struct input_dev *input;
121 struct regulator *vcc33;
122 struct regulator *vccio;
123 struct gpio_desc *reset_gpio;
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;
136 enum elants_state state;
137 enum elants_iap_mode iap_mode;
139 /* Guards against concurrent access to the device via sysfs */
140 struct mutex sysfs_mutex;
142 u8 cmd_resp[HEADER_SIZE];
143 struct completion cmd_done;
145 bool wake_irq_enabled;
146 bool keep_power_in_suspend;
148 /* Must be last to be used for DMA operations */
149 u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
152 static int elants_i2c_send(struct i2c_client *client,
153 const void *data, size_t size)
155 int ret;
157 ret = i2c_master_send(client, data, size);
158 if (ret == size)
159 return 0;
161 if (ret >= 0)
162 ret = -EIO;
164 dev_err(&client->dev, "%s failed (%*ph): %d\n",
165 __func__, (int)size, data, ret);
167 return ret;
170 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
172 int ret;
174 ret = i2c_master_recv(client, data, size);
175 if (ret == size)
176 return 0;
178 if (ret >= 0)
179 ret = -EIO;
181 dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
183 return ret;
186 static int elants_i2c_execute_command(struct i2c_client *client,
187 const u8 *cmd, size_t cmd_size,
188 u8 *resp, size_t resp_size)
190 struct i2c_msg msgs[2];
191 int ret;
192 u8 expected_response;
194 switch (cmd[0]) {
195 case CMD_HEADER_READ:
196 expected_response = CMD_HEADER_RESP;
197 break;
199 case CMD_HEADER_6B_READ:
200 expected_response = CMD_HEADER_6B_RESP;
201 break;
203 default:
204 dev_err(&client->dev, "%s: invalid command %*ph\n",
205 __func__, (int)cmd_size, cmd);
206 return -EINVAL;
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;
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;
220 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
221 if (ret < 0)
222 return ret;
224 if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
225 return -EIO;
227 return 0;
230 static int elants_i2c_calibrate(struct elants_data *ts)
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 };
238 disable_irq(client->irq);
240 ts->state = ELAN_WAIT_RECALIBRATION;
241 reinit_completion(&ts->cmd_done);
243 elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
244 elants_i2c_send(client, rek, sizeof(rek));
246 enable_irq(client->irq);
248 ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
249 msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
251 ts->state = ELAN_STATE_NORMAL;
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;
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;
268 return 0;
271 static int elants_i2c_sw_reset(struct i2c_client *client)
273 const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
274 int error;
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;
284 * We should wait at least 10 msec (but no more than 40) before
285 * sending fastboot or IAP command to the device.
287 msleep(30);
289 return 0;
292 static u16 elants_i2c_parse_version(u8 *buf)
294 return get_unaligned_be32(buf) >> 4;
297 static int elants_i2c_query_hw_version(struct elants_data *ts)
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];
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;
313 dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
314 error, (int)sizeof(resp), resp);
317 if (error) {
318 dev_err(&client->dev,
319 "Failed to read fw id: %d\n", error);
320 return error;
323 dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
325 return -EINVAL;
328 static int elants_i2c_query_fw_version(struct elants_data *ts)
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];
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;
345 dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
346 error, (int)sizeof(resp), resp);
349 dev_err(&client->dev,
350 "Failed to read fw version or fw version is invalid\n");
352 return -EINVAL;
355 static int elants_i2c_query_test_version(struct elants_data *ts)
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];
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;
371 return 0;
374 dev_dbg(&client->dev,
375 "read test version error rc=%d, buf=%*phC\n",
376 error, (int)sizeof(resp), resp);
379 dev_err(&client->dev, "Failed to read test version\n");
381 return -EINVAL;
384 static int elants_i2c_query_bc_version(struct elants_data *ts)
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;
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;
401 version = elants_i2c_parse_version(resp);
402 ts->bc_version = version >> 8;
403 ts->iap_version = version & 0xff;
405 return 0;
408 static int elants_i2c_query_ts_info(struct elants_data *ts)
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
417 const u8 get_osr_cmd[] = {
418 CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
420 const u8 get_physical_scan_cmd[] = {
421 CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
423 const u8 get_physical_drive_cmd[] = {
424 CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
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;
438 rows = resp[2] + resp[6] + resp[10];
439 cols = resp[3] + resp[7] + resp[11];
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;
451 osr = resp[3];
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;
463 phy_x = get_unaligned_be16(&resp[2]);
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;
475 phy_y = get_unaligned_be16(&resp[2]);
477 dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
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);
491 return 0;
494 static int elants_i2c_fastboot(struct i2c_client *client)
496 const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
497 int error;
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;
505 dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
506 return 0;
509 static int elants_i2c_initialize(struct elants_data *ts)
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];
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;
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;
532 /* Wait for Hello packet */
533 msleep(BOOT_TIME_DELAY_MS);
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))) {
544 * Setting error code will mark device
545 * in recovery mode below.
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);
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;
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);
571 if (error)
572 ts->iap_mode = ELAN_IAP_RECOVERY;
574 return 0;
578 * Firmware update interface.
581 static int elants_i2c_fw_write_page(struct i2c_client *client,
582 const void *page)
584 const u8 ack_ok[] = { 0xaa, 0xaa };
585 u8 buf[2];
586 int retry;
587 int error;
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;
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;
604 if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
605 return 0;
607 error = -EIO;
608 dev_err(&client->dev,
609 "IAP Get Ack Error [%02x:%02x]\n",
610 buf[0], buf[1]);
613 return error;
616 static int elants_i2c_do_update_firmware(struct i2c_client *client,
617 const struct firmware *fw,
618 bool force)
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;
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));
646 if (error) {
647 dev_err(&client->dev, "failed to enter IAP mode: %d\n", error);
648 return error;
651 msleep(20);
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;
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;
669 dev_info(&client->dev, "successfully entered IAP mode");
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;
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;
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;
695 n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
696 dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
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;
709 /* Old iap needs to wait 200ms for WDT and rest is for hello packets */
710 msleep(300);
712 dev_info(&client->dev, "firmware update completed\n");
713 return 0;
716 static int elants_i2c_fw_update(struct elants_data *ts)
718 struct i2c_client *client = ts->client;
719 const struct firmware *fw;
720 char *fw_name;
721 int error;
723 fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
724 if (!fw_name)
725 return -ENOMEM;
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;
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;
743 disable_irq(client->irq);
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;
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;
762 ts->iap_mode = ELAN_IAP_OPERATIONAL;
764 out_enable_irq:
765 ts->state = ELAN_STATE_NORMAL;
766 enable_irq(client->irq);
767 msleep(100);
769 if (!error)
770 elants_i2c_calibrate(ts);
771 out:
772 release_firmware(fw);
773 return error;
777 * Event reporting.
780 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
782 struct input_dev *input = ts->input;
783 unsigned int n_fingers;
784 u16 finger_state;
785 int i;
787 n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
788 finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
789 buf[FW_POS_STATE];
791 dev_dbg(&ts->client->dev,
792 "n_fingers: %u, state: %04x\n", n_fingers, finger_state);
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;
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];
805 dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
806 i, x, y, p, w);
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);
815 n_fingers--;
818 finger_state >>= 1;
821 input_mt_sync_frame(input);
822 input_sync(input);
825 static u8 elants_i2c_calculate_checksum(u8 *buf)
827 u8 checksum = 0;
828 u8 i;
830 for (i = 0; i < FW_POS_CHECKSUM; i++)
831 checksum += buf[i];
833 return checksum;
836 static void elants_i2c_event(struct elants_data *ts, u8 *buf)
838 u8 checksum = elants_i2c_calculate_checksum(buf);
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);
853 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
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;
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;
869 dev_dbg(&client->dev, "%s: packet %*ph\n",
870 __func__, HEADER_SIZE, ts->buf);
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;
879 break;
881 case ELAN_WAIT_QUEUE_HEADER:
882 if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
883 break;
885 ts->state = ELAN_STATE_NORMAL;
886 /* fall through */
888 case ELAN_STATE_NORMAL:
890 switch (ts->buf[FW_HDR_TYPE]) {
891 case CMD_HEADER_HELLO:
892 case CMD_HEADER_RESP:
893 case CMD_HEADER_REK:
894 break;
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);
905 break;
907 case QUEUE_HEADER_SINGLE:
908 elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
909 break;
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;
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;
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);
933 break;
935 default:
936 dev_err(&client->dev, "unknown packet %*ph\n",
937 HEADER_SIZE, ts->buf);
938 break;
940 break;
943 out:
944 return IRQ_HANDLED;
948 * sysfs interface
950 static ssize_t calibrate_store(struct device *dev,
951 struct device_attribute *attr,
952 const char *buf, size_t count)
954 struct i2c_client *client = to_i2c_client(dev);
955 struct elants_data *ts = i2c_get_clientdata(client);
956 int error;
958 error = mutex_lock_interruptible(&ts->sysfs_mutex);
959 if (error)
960 return error;
962 error = elants_i2c_calibrate(ts);
964 mutex_unlock(&ts->sysfs_mutex);
965 return error ?: count;
968 static ssize_t write_update_fw(struct device *dev,
969 struct device_attribute *attr,
970 const char *buf, size_t count)
972 struct i2c_client *client = to_i2c_client(dev);
973 struct elants_data *ts = i2c_get_clientdata(client);
974 int error;
976 error = mutex_lock_interruptible(&ts->sysfs_mutex);
977 if (error)
978 return error;
980 error = elants_i2c_fw_update(ts);
981 dev_dbg(dev, "firmware update result: %d\n", error);
983 mutex_unlock(&ts->sysfs_mutex);
984 return error ?: count;
987 static ssize_t show_iap_mode(struct device *dev,
988 struct device_attribute *attr, char *buf)
990 struct i2c_client *client = to_i2c_client(dev);
991 struct elants_data *ts = i2c_get_clientdata(client);
993 return sprintf(buf, "%s\n",
994 ts->iap_mode == ELAN_IAP_OPERATIONAL ?
995 "Normal" : "Recovery");
998 static DEVICE_ATTR_WO(calibrate);
999 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1000 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1002 struct elants_version_attribute {
1003 struct device_attribute dattr;
1004 size_t field_offset;
1005 size_t field_size;
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), \
1021 static ssize_t elants_version_attribute_show(struct device *dev,
1022 struct device_attribute *dattr,
1023 char *buf)
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;
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 */
1041 return sprintf(buf, "%0*x\n", fmt_size, val);
1044 static ELANTS_VERSION_ATTR(fw_version);
1045 static ELANTS_VERSION_ATTR(hw_version);
1046 static ELANTS_VERSION_ATTR(test_version);
1047 static ELANTS_VERSION_ATTR(solution_version);
1048 static ELANTS_VERSION_ATTR(bc_version);
1049 static ELANTS_VERSION_ATTR(iap_version);
1051 static struct attribute *elants_attributes[] = {
1052 &dev_attr_calibrate.attr,
1053 &dev_attr_update_fw.attr,
1054 &dev_attr_iap_mode.attr,
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
1065 static const struct attribute_group elants_attribute_group = {
1066 .attrs = elants_attributes,
1069 static int elants_i2c_power_on(struct elants_data *ts)
1071 int error;
1074 * If we do not have reset gpio assume platform firmware
1075 * controls regulators and does power them on for us.
1077 if (IS_ERR_OR_NULL(ts->reset_gpio))
1078 return 0;
1080 gpiod_set_value_cansleep(ts->reset_gpio, 1);
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;
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;
1100 * We need to wait a bit after powering on controller before
1101 * we are allowed to release reset GPIO.
1103 udelay(ELAN_POWERON_DELAY_USEC);
1105 release_reset_gpio:
1106 gpiod_set_value_cansleep(ts->reset_gpio, 0);
1107 if (error)
1108 return error;
1110 msleep(ELAN_RESET_DELAY_MSEC);
1112 return 0;
1115 static void elants_i2c_power_off(void *_data)
1117 struct elants_data *ts = _data;
1119 if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1121 * Activate reset gpio to prevent leakage through the
1122 * pin once we shut off power to the controller.
1124 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1125 regulator_disable(ts->vccio);
1126 regulator_disable(ts->vcc33);
1130 static int elants_i2c_probe(struct i2c_client *client,
1131 const struct i2c_device_id *id)
1133 union i2c_smbus_data dummy;
1134 struct elants_data *ts;
1135 unsigned long irqflags;
1136 int error;
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;
1144 ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1145 if (!ts)
1146 return -ENOMEM;
1148 mutex_init(&ts->sysfs_mutex);
1149 init_completion(&ts->cmd_done);
1151 ts->client = client;
1152 i2c_set_clientdata(client, ts);
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;
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;
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);
1178 if (error == -EPROBE_DEFER)
1179 return error;
1181 if (error != -ENOENT && error != -ENOSYS) {
1182 dev_err(&client->dev,
1183 "failed to get reset gpio: %d\n",
1184 error);
1185 return error;
1188 ts->keep_power_in_suspend = true;
1191 error = elants_i2c_power_on(ts);
1192 if (error)
1193 return error;
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;
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;
1210 error = elants_i2c_initialize(ts);
1211 if (error) {
1212 dev_err(&client->dev, "failed to initialize: %d\n", error);
1213 return error;
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;
1222 ts->input->name = "Elan Touchscreen";
1223 ts->input->id.bustype = BUS_I2C;
1225 __set_bit(BTN_TOUCH, ts->input->keybit);
1226 __set_bit(EV_ABS, ts->input->evbit);
1227 __set_bit(EV_KEY, ts->input->evbit);
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);
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;
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);
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;
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.
1264 irqflags = irq_get_trigger_type(client->irq);
1265 if (!irqflags)
1266 irqflags = IRQF_TRIGGER_FALLING;
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;
1278 * Systems using device tree should set up wakeup via DTS,
1279 * the rest will configure device as wakeup source by default.
1281 if (!client->dev.of_node)
1282 device_init_wakeup(&client->dev, true);
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;
1291 return 0;
1294 static int __maybe_unused elants_i2c_suspend(struct device *dev)
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;
1302 /* Command not support in IAP recovery mode */
1303 if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1304 return -EBUSY;
1306 disable_irq(client->irq);
1308 if (device_may_wakeup(dev)) {
1310 * The device will automatically enter idle mode
1311 * that has reduced power consumption.
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;
1321 dev_err(&client->dev,
1322 "suspend command failed: %d\n", error);
1324 } else {
1325 elants_i2c_power_off(ts);
1328 return 0;
1331 static int __maybe_unused elants_i2c_resume(struct device *dev)
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;
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;
1350 dev_err(&client->dev,
1351 "resume command failed: %d\n", error);
1353 } else {
1354 elants_i2c_power_on(ts);
1355 elants_i2c_initialize(ts);
1358 ts->state = ELAN_STATE_NORMAL;
1359 enable_irq(client->irq);
1361 return 0;
1364 static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1365 elants_i2c_suspend, elants_i2c_resume);
1367 static const struct i2c_device_id elants_i2c_id[] = {
1368 { DEVICE_NAME, 0 },
1371 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1373 #ifdef CONFIG_ACPI
1374 static const struct acpi_device_id elants_acpi_id[] = {
1375 { "ELAN0001", 0 },
1378 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1379 #endif
1381 #ifdef CONFIG_OF
1382 static const struct of_device_id elants_of_match[] = {
1383 { .compatible = "elan,ekth3500" },
1384 { /* sentinel */ }
1386 MODULE_DEVICE_TABLE(of, elants_of_match);
1387 #endif
1389 static 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,
1400 module_i2c_driver(elants_i2c_driver);
1402 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1403 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1404 MODULE_LICENSE("GPL");