drivers/input/touchscreen/elants_i2c.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Elan Microelectronics touch panels with I2C interface
   4  *
   5  * Copyright (C) 2014 Elan Microelectronics Corporation.
   6  * Scott Liu <scott.liu@emc.com.tw>
   7  *
   8  * This code is partly based on hid-multitouch.c:
   9  *
  10  *  Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
  11  *  Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
  12  *  Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
  13  *
  14  * This code is partly based on i2c-hid.c:
  15  *
  16  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
  17  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
  18  * Copyright (c) 2012 Red Hat, Inc
  19  */
  20
  21
  22 #include <linux/bits.h>
  23 #include <linux/module.h>
  24 #include <linux/input.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/irq.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/async.h>
  29 #include <linux/i2c.h>
  30 #include <linux/delay.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/buffer_head.h>
  33 #include <linux/slab.h>
  34 #include <linux/firmware.h>
  35 #include <linux/input/mt.h>
  36 #include <linux/input/touchscreen.h>
  37 #include <linux/acpi.h>
  38 #include <linux/of.h>
  39 #include <linux/gpio/consumer.h>
  40 #include <linux/regulator/consumer.h>
  41 #include <asm/unaligned.h>
  42
  43 /* Device, Driver information */
  44 #define DEVICE_NAME     "elants_i2c"
  45
  46 /* Convert from rows or columns into resolution */
  47 #define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
  48
  49 /* FW header data */
  50 #define HEADER_SIZE             4
  51 #define FW_HDR_TYPE             0
  52 #define FW_HDR_COUNT            1
  53 #define FW_HDR_LENGTH           2
  54
  55 /* Buffer mode Queue Header information */
  56 #define QUEUE_HEADER_SINGLE     0x62
  57 #define QUEUE_HEADER_NORMAL     0X63
  58 #define QUEUE_HEADER_WAIT       0x64
  59
  60 /* Command header definition */
  61 #define CMD_HEADER_WRITE        0x54
  62 #define CMD_HEADER_READ         0x53
  63 #define CMD_HEADER_6B_READ      0x5B
  64 #define CMD_HEADER_ROM_READ     0x96
  65 #define CMD_HEADER_RESP         0x52
  66 #define CMD_HEADER_6B_RESP      0x9B
  67 #define CMD_HEADER_ROM_RESP     0x95
  68 #define CMD_HEADER_HELLO        0x55
  69 #define CMD_HEADER_REK          0x66
  70
  71 /* FW position data */
  72 #define PACKET_SIZE             55
  73 #define MAX_CONTACT_NUM         10
  74 #define FW_POS_HEADER           0
  75 #define FW_POS_STATE            1
  76 #define FW_POS_TOTAL            2
  77 #define FW_POS_XY               3
  78 #define FW_POS_TOOL_TYPE        33
  79 #define FW_POS_CHECKSUM         34
  80 #define FW_POS_WIDTH            35
  81 #define FW_POS_PRESSURE         45
  82
  83 #define HEADER_REPORT_10_FINGER 0x62
  84
  85 /* Header (4 bytes) plus 3 full 10-finger packets */
  86 #define MAX_PACKET_SIZE         169
  87
  88 #define BOOT_TIME_DELAY_MS      50
  89
  90 /* FW read command, 0x53 0x?? 0x0, 0x01 */
  91 #define E_ELAN_INFO_FW_VER      0x00
  92 #define E_ELAN_INFO_BC_VER      0x10
  93 #define E_ELAN_INFO_REK         0xD0
  94 #define E_ELAN_INFO_TEST_VER    0xE0
  95 #define E_ELAN_INFO_FW_ID       0xF0
  96 #define E_INFO_OSR              0xD6
  97 #define E_INFO_PHY_SCAN         0xD7
  98 #define E_INFO_PHY_DRIVER       0xD8
  99
 100 /* FW write command, 0x54 0x?? 0x0, 0x01 */
 101 #define E_POWER_STATE_SLEEP     0x50
 102 #define E_POWER_STATE_RESUME    0x58
 103
 104 #define MAX_RETRIES             3
 105 #define MAX_FW_UPDATE_RETRIES   30
 106
 107 #define ELAN_FW_PAGESIZE        132
 108
 109 /* calibration timeout definition */
 110 #define ELAN_CALI_TIMEOUT_MSEC  12000
 111
 112 #define ELAN_POWERON_DELAY_USEC 500
 113 #define ELAN_RESET_DELAY_MSEC   20
 114
 115 enum elants_state {
 116         ELAN_STATE_NORMAL,
 117         ELAN_WAIT_QUEUE_HEADER,
 118         ELAN_WAIT_RECALIBRATION,
 119 };
 120
 121 enum elants_iap_mode {
 122         ELAN_IAP_OPERATIONAL,
 123         ELAN_IAP_RECOVERY,
 124 };
 125
 126 /* struct elants_data - represents state of Elan touchscreen device */
 127 struct elants_data {
 128         struct i2c_client *client;
 129         struct input_dev *input;
 130
 131         struct regulator *vcc33;
 132         struct regulator *vccio;
 133         struct gpio_desc *reset_gpio;
 134
 135         u16 fw_version;
 136         u8 test_version;
 137         u8 solution_version;
 138         u8 bc_version;
 139         u8 iap_version;
 140         u16 hw_version;
 141         u8 major_res;
 142         unsigned int x_res;     /* resolution in units/mm */
 143         unsigned int y_res;
 144         unsigned int x_max;
 145         unsigned int y_max;
 146         struct touchscreen_properties prop;
 147
 148         enum elants_state state;
 149         enum elants_iap_mode iap_mode;
 150
 151         /* Guards against concurrent access to the device via sysfs */
 152         struct mutex sysfs_mutex;
 153
 154         u8 cmd_resp[HEADER_SIZE];
 155         struct completion cmd_done;
 156
 157         bool wake_irq_enabled;
 158         bool keep_power_in_suspend;
 159
 160         /* Must be last to be used for DMA operations */
 161         u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
 162 };
 163
 164 static int elants_i2c_send(struct i2c_client *client,
 165                            const void *data, size_t size)
 166 {
 167         int ret;
 168
 169         ret = i2c_master_send(client, data, size);
 170         if (ret == size)
 171                 return 0;
 172
 173         if (ret >= 0)
 174                 ret = -EIO;
 175
 176         dev_err(&client->dev, "%s failed (%*ph): %d\n",
 177                 __func__, (int)size, data, ret);
 178
 179         return ret;
 180 }
 181
 182 static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
 183 {
 184         int ret;
 185
 186         ret = i2c_master_recv(client, data, size);
 187         if (ret == size)
 188                 return 0;
 189
 190         if (ret >= 0)
 191                 ret = -EIO;
 192
 193         dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
 194
 195         return ret;
 196 }
 197
 198 static int elants_i2c_execute_command(struct i2c_client *client,
 199                                       const u8 *cmd, size_t cmd_size,
 200                                       u8 *resp, size_t resp_size,
 201                                       int retries, const char *cmd_name)
 202 {
 203         struct i2c_msg msgs[2];
 204         int ret;
 205         u8 expected_response;
 206
 207         switch (cmd[0]) {
 208         case CMD_HEADER_READ:
 209                 expected_response = CMD_HEADER_RESP;
 210                 break;
 211
 212         case CMD_HEADER_6B_READ:
 213                 expected_response = CMD_HEADER_6B_RESP;
 214                 break;
 215
 216         case CMD_HEADER_ROM_READ:
 217                 expected_response = CMD_HEADER_ROM_RESP;
 218                 break;
 219
 220         default:
 221                 dev_err(&client->dev, "(%s): invalid command: %*ph\n",
 222                         cmd_name, (int)cmd_size, cmd);
 223                 return -EINVAL;
 224         }
 225
 226         for (;;) {
 227                 msgs[0].addr = client->addr;
 228                 msgs[0].flags = client->flags & I2C_M_TEN;
 229                 msgs[0].len = cmd_size;
 230                 msgs[0].buf = (u8 *)cmd;
 231
 232                 msgs[1].addr = client->addr;
 233                 msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
 234                 msgs[1].flags |= I2C_M_RD;
 235                 msgs[1].len = resp_size;
 236                 msgs[1].buf = resp;
 237
 238                 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
 239                 if (ret < 0) {
 240                         if (--retries > 0) {
 241                                 dev_dbg(&client->dev,
 242                                         "(%s) I2C transfer failed: %pe (retrying)\n",
 243                                         cmd_name, ERR_PTR(ret));
 244                                 continue;
 245                         }
 246
 247                         dev_err(&client->dev,
 248                                 "(%s) I2C transfer failed: %pe\n",
 249                                 cmd_name, ERR_PTR(ret));
 250                         return ret;
 251                 }
 252
 253                 if (ret != ARRAY_SIZE(msgs) ||
 254                     resp[FW_HDR_TYPE] != expected_response) {
 255                         if (--retries > 0) {
 256                                 dev_dbg(&client->dev,
 257                                         "(%s) unexpected response: %*ph (retrying)\n",
 258                                         cmd_name, ret, resp);
 259                                 continue;
 260                         }
 261
 262                         dev_err(&client->dev,
 263                                 "(%s) unexpected response: %*ph\n",
 264                                 cmd_name, ret, resp);
 265                         return -EIO;
 266                 }
 267
 268                 return 0;
 269         }
 270 }
 271
 272 static int elants_i2c_calibrate(struct elants_data *ts)
 273 {
 274         struct i2c_client *client = ts->client;
 275         int ret, error;
 276         static const u8 w_flashkey[] = { CMD_HEADER_WRITE, 0xC0, 0xE1, 0x5A };
 277         static const u8 rek[] = { CMD_HEADER_WRITE, 0x29, 0x00, 0x01 };
 278         static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
 279
 280         disable_irq(client->irq);
 281
 282         ts->state = ELAN_WAIT_RECALIBRATION;
 283         reinit_completion(&ts->cmd_done);
 284
 285         elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
 286         elants_i2c_send(client, rek, sizeof(rek));
 287
 288         enable_irq(client->irq);
 289
 290         ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
 291                                 msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
 292
 293         ts->state = ELAN_STATE_NORMAL;
 294
 295         if (ret <= 0) {
 296                 error = ret < 0 ? ret : -ETIMEDOUT;
 297                 dev_err(&client->dev,
 298                         "error while waiting for calibration to complete: %d\n",
 299                         error);
 300                 return error;
 301         }
 302
 303         if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
 304                 dev_err(&client->dev,
 305                         "unexpected calibration response: %*ph\n",
 306                         (int)sizeof(ts->cmd_resp), ts->cmd_resp);
 307                 return -EINVAL;
 308         }
 309
 310         return 0;
 311 }
 312
 313 static int elants_i2c_sw_reset(struct i2c_client *client)
 314 {
 315         const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
 316         int error;
 317
 318         error = elants_i2c_send(client, soft_rst_cmd,
 319                                 sizeof(soft_rst_cmd));
 320         if (error) {
 321                 dev_err(&client->dev, "software reset failed: %d\n", error);
 322                 return error;
 323         }
 324
 325         /*
 326          * We should wait at least 10 msec (but no more than 40) before
 327          * sending fastboot or IAP command to the device.
 328          */
 329         msleep(30);
 330
 331         return 0;
 332 }
 333
 334 static u16 elants_i2c_parse_version(u8 *buf)
 335 {
 336         return get_unaligned_be32(buf) >> 4;
 337 }
 338
 339 static int elants_i2c_query_hw_version(struct elants_data *ts)
 340 {
 341         struct i2c_client *client = ts->client;
 342         int retry_cnt = MAX_RETRIES;
 343         const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
 344         u8 resp[HEADER_SIZE];
 345         int error;
 346
 347         while (retry_cnt--) {
 348                 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
 349                                                    resp, sizeof(resp), 1,
 350                                                    "read fw id");
 351                 if (error)
 352                         return error;
 353
 354                 ts->hw_version = elants_i2c_parse_version(resp);
 355                 if (ts->hw_version != 0xffff)
 356                         return 0;
 357         }
 358
 359         dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
 360
 361         return -EINVAL;
 362 }
 363
 364 static int elants_i2c_query_fw_version(struct elants_data *ts)
 365 {
 366         struct i2c_client *client = ts->client;
 367         int retry_cnt = MAX_RETRIES;
 368         const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
 369         u8 resp[HEADER_SIZE];
 370         int error;
 371
 372         while (retry_cnt--) {
 373                 error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
 374                                                    resp, sizeof(resp), 1,
 375                                                    "read fw version");
 376                 if (error)
 377                         return error;
 378
 379                 ts->fw_version = elants_i2c_parse_version(resp);
 380                 if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
 381                         return 0;
 382
 383                 dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
 384                         (int)sizeof(resp), resp);
 385         }
 386
 387         dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
 388
 389         return -EINVAL;
 390 }
 391
 392 static int elants_i2c_query_test_version(struct elants_data *ts)
 393 {
 394         struct i2c_client *client = ts->client;
 395         int error;
 396         u16 version;
 397         const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
 398         u8 resp[HEADER_SIZE];
 399
 400         error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
 401                                            resp, sizeof(resp), MAX_RETRIES,
 402                                            "read test version");
 403         if (error) {
 404                 dev_err(&client->dev, "Failed to read test version\n");
 405                 return error;
 406         }
 407
 408         version = elants_i2c_parse_version(resp);
 409         ts->test_version = version >> 8;
 410         ts->solution_version = version & 0xff;
 411
 412         return 0;
 413 }
 414
 415 static int elants_i2c_query_bc_version(struct elants_data *ts)
 416 {
 417         struct i2c_client *client = ts->client;
 418         const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
 419         u8 resp[HEADER_SIZE];
 420         u16 version;
 421         int error;
 422
 423         error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
 424                                            resp, sizeof(resp), 1,
 425                                            "read BC version");
 426         if (error)
 427                 return error;
 428
 429         version = elants_i2c_parse_version(resp);
 430         ts->bc_version = version >> 8;
 431         ts->iap_version = version & 0xff;
 432
 433         return 0;
 434 }
 435
 436 static int elants_i2c_query_ts_info(struct elants_data *ts)
 437 {
 438         struct i2c_client *client = ts->client;
 439         int error;
 440         u8 resp[17];
 441         u16 phy_x, phy_y, rows, cols, osr;
 442         const u8 get_resolution_cmd[] = {
 443                 CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
 444         };
 445         const u8 get_osr_cmd[] = {
 446                 CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
 447         };
 448         const u8 get_physical_scan_cmd[] = {
 449                 CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
 450         };
 451         const u8 get_physical_drive_cmd[] = {
 452                 CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
 453         };
 454
 455         /* Get trace number */
 456         error = elants_i2c_execute_command(client,
 457                                            get_resolution_cmd,
 458                                            sizeof(get_resolution_cmd),
 459                                            resp, sizeof(resp), 1,
 460                                            "get resolution");
 461         if (error)
 462                 return error;
 463
 464         rows = resp[2] + resp[6] + resp[10];
 465         cols = resp[3] + resp[7] + resp[11];
 466
 467         /* Get report resolution value of ABS_MT_TOUCH_MAJOR */
 468         ts->major_res = resp[16];
 469
 470         /* Process mm_to_pixel information */
 471         error = elants_i2c_execute_command(client,
 472                                            get_osr_cmd, sizeof(get_osr_cmd),
 473                                            resp, sizeof(resp), 1, "get osr");
 474         if (error)
 475                 return error;
 476
 477         osr = resp[3];
 478
 479         error = elants_i2c_execute_command(client,
 480                                            get_physical_scan_cmd,
 481                                            sizeof(get_physical_scan_cmd),
 482                                            resp, sizeof(resp), 1,
 483                                            "get physical scan");
 484         if (error)
 485                 return error;
 486
 487         phy_x = get_unaligned_be16(&resp[2]);
 488
 489         error = elants_i2c_execute_command(client,
 490                                            get_physical_drive_cmd,
 491                                            sizeof(get_physical_drive_cmd),
 492                                            resp, sizeof(resp), 1,
 493                                            "get physical drive");
 494         if (error)
 495                 return error;
 496
 497         phy_y = get_unaligned_be16(&resp[2]);
 498
 499         dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
 500
 501         if (rows == 0 || cols == 0 || osr == 0) {
 502                 dev_warn(&client->dev,
 503                          "invalid trace number data: %d, %d, %d\n",
 504                          rows, cols, osr);
 505         } else {
 506                 /* translate trace number to TS resolution */
 507                 ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
 508                 ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
 509                 ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
 510                 ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
 511         }
 512
 513         return 0;
 514 }
 515
 516 static int elants_i2c_fastboot(struct i2c_client *client)
 517 {
 518         const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
 519         int error;
 520
 521         error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
 522         if (error) {
 523                 dev_err(&client->dev, "boot failed: %d\n", error);
 524                 return error;
 525         }
 526
 527         dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
 528         return 0;
 529 }
 530
 531 static int elants_i2c_initialize(struct elants_data *ts)
 532 {
 533         struct i2c_client *client = ts->client;
 534         int error, error2, retry_cnt;
 535         const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
 536         const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
 537         u8 buf[HEADER_SIZE];
 538
 539         for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
 540                 error = elants_i2c_sw_reset(client);
 541                 if (error) {
 542                         /* Continue initializing if it's the last try */
 543                         if (retry_cnt < MAX_RETRIES - 1)
 544                                 continue;
 545                 }
 546
 547                 error = elants_i2c_fastboot(client);
 548                 if (error) {
 549                         /* Continue initializing if it's the last try */
 550                         if (retry_cnt < MAX_RETRIES - 1)
 551                                 continue;
 552                 }
 553
 554                 /* Wait for Hello packet */
 555                 msleep(BOOT_TIME_DELAY_MS);
 556
 557                 error = elants_i2c_read(client, buf, sizeof(buf));
 558                 if (error) {
 559                         dev_err(&client->dev,
 560                                 "failed to read 'hello' packet: %d\n", error);
 561                 } else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
 562                         ts->iap_mode = ELAN_IAP_OPERATIONAL;
 563                         break;
 564                 } else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
 565                         /*
 566                          * Setting error code will mark device
 567                          * in recovery mode below.
 568                          */
 569                         error = -EIO;
 570                         break;
 571                 } else {
 572                         error = -EINVAL;
 573                         dev_err(&client->dev,
 574                                 "invalid 'hello' packet: %*ph\n",
 575                                 (int)sizeof(buf), buf);
 576                 }
 577         }
 578
 579         /* hw version is available even if device in recovery state */
 580         error2 = elants_i2c_query_hw_version(ts);
 581         if (!error2)
 582                 error2 = elants_i2c_query_bc_version(ts);
 583         if (!error)
 584                 error = error2;
 585
 586         if (!error)
 587                 error = elants_i2c_query_fw_version(ts);
 588         if (!error)
 589                 error = elants_i2c_query_test_version(ts);
 590         if (!error)
 591                 error = elants_i2c_query_ts_info(ts);
 592
 593         if (error)
 594                 ts->iap_mode = ELAN_IAP_RECOVERY;
 595
 596         return 0;
 597 }
 598
 599 /*
 600  * Firmware update interface.
 601  */
 602
 603 static int elants_i2c_fw_write_page(struct i2c_client *client,
 604                                     const void *page)
 605 {
 606         const u8 ack_ok[] = { 0xaa, 0xaa };
 607         u8 buf[2];
 608         int retry;
 609         int error;
 610
 611         for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
 612                 error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
 613                 if (error) {
 614                         dev_err(&client->dev,
 615                                 "IAP Write Page failed: %d\n", error);
 616                         continue;
 617                 }
 618
 619                 error = elants_i2c_read(client, buf, 2);
 620                 if (error) {
 621                         dev_err(&client->dev,
 622                                 "IAP Ack read failed: %d\n", error);
 623                         return error;
 624                 }
 625
 626                 if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
 627                         return 0;
 628
 629                 error = -EIO;
 630                 dev_err(&client->dev,
 631                         "IAP Get Ack Error [%02x:%02x]\n",
 632                         buf[0], buf[1]);
 633         }
 634
 635         return error;
 636 }
 637
 638 static int elants_i2c_validate_remark_id(struct elants_data *ts,
 639                                          const struct firmware *fw)
 640 {
 641         struct i2c_client *client = ts->client;
 642         int error;
 643         const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
 644         u8 resp[6] = { 0 };
 645         u16 ts_remark_id = 0;
 646         u16 fw_remark_id = 0;
 647
 648         /* Compare TS Remark ID and FW Remark ID */
 649         error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
 650                                            resp, sizeof(resp),
 651                                            1, "read Remark ID");
 652         if (error)
 653                 return error;
 654
 655         ts_remark_id = get_unaligned_be16(&resp[3]);
 656
 657         fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
 658
 659         if (fw_remark_id != ts_remark_id) {
 660                 dev_err(&client->dev,
 661                         "Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
 662                         ts_remark_id, fw_remark_id);
 663                 return -EINVAL;
 664         }
 665
 666         return 0;
 667 }
 668
 669 static int elants_i2c_do_update_firmware(struct i2c_client *client,
 670                                          const struct firmware *fw,
 671                                          bool force)
 672 {
 673         struct elants_data *ts = i2c_get_clientdata(client);
 674         const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
 675         const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
 676         const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
 677         const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
 678         u8 buf[HEADER_SIZE];
 679         u16 send_id;
 680         int page, n_fw_pages;
 681         int error;
 682         bool check_remark_id = ts->iap_version >= 0x60;
 683
 684         /* Recovery mode detection! */
 685         if (force) {
 686                 dev_dbg(&client->dev, "Recovery mode procedure\n");
 687
 688                 if (check_remark_id) {
 689                         error = elants_i2c_validate_remark_id(ts, fw);
 690                         if (error)
 691                                 return error;
 692                 }
 693
 694                 error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
 695                 if (error) {
 696                         dev_err(&client->dev, "failed to enter IAP mode: %d\n",
 697                                 error);
 698                         return error;
 699                 }
 700         } else {
 701                 /* Start IAP Procedure */
 702                 dev_dbg(&client->dev, "Normal IAP procedure\n");
 703
 704                 /* Close idle mode */
 705                 error = elants_i2c_send(client, close_idle, sizeof(close_idle));
 706                 if (error)
 707                         dev_err(&client->dev, "Failed close idle: %d\n", error);
 708                 msleep(60);
 709
 710                 elants_i2c_sw_reset(client);
 711                 msleep(20);
 712
 713                 if (check_remark_id) {
 714                         error = elants_i2c_validate_remark_id(ts, fw);
 715                         if (error)
 716                                 return error;
 717                 }
 718
 719                 error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
 720                 if (error) {
 721                         dev_err(&client->dev, "failed to enter IAP mode: %d\n",
 722                                 error);
 723                         return error;
 724                 }
 725         }
 726
 727         msleep(20);
 728
 729         /* check IAP state */
 730         error = elants_i2c_read(client, buf, 4);
 731         if (error) {
 732                 dev_err(&client->dev,
 733                         "failed to read IAP acknowledgement: %d\n",
 734                         error);
 735                 return error;
 736         }
 737
 738         if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
 739                 dev_err(&client->dev,
 740                         "failed to enter IAP: %*ph (expected %*ph)\n",
 741                         (int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
 742                 return -EIO;
 743         }
 744
 745         dev_info(&client->dev, "successfully entered IAP mode");
 746
 747         send_id = client->addr;
 748         error = elants_i2c_send(client, &send_id, 1);
 749         if (error) {
 750                 dev_err(&client->dev, "sending dummy byte failed: %d\n",
 751                         error);
 752                 return error;
 753         }
 754
 755         /* Clear the last page of Master */
 756         error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
 757         if (error) {
 758                 dev_err(&client->dev, "clearing of the last page failed: %d\n",
 759                         error);
 760                 return error;
 761         }
 762
 763         error = elants_i2c_read(client, buf, 2);
 764         if (error) {
 765                 dev_err(&client->dev,
 766                         "failed to read ACK for clearing the last page: %d\n",
 767                         error);
 768                 return error;
 769         }
 770
 771         n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
 772         dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
 773
 774         for (page = 0; page < n_fw_pages; page++) {
 775                 error = elants_i2c_fw_write_page(client,
 776                                         fw->data + page * ELAN_FW_PAGESIZE);
 777                 if (error) {
 778                         dev_err(&client->dev,
 779                                 "failed to write FW page %d: %d\n",
 780                                 page, error);
 781                         return error;
 782                 }
 783         }
 784
 785         /* Old iap needs to wait 200ms for WDT and rest is for hello packets */
 786         msleep(300);
 787
 788         dev_info(&client->dev, "firmware update completed\n");
 789         return 0;
 790 }
 791
 792 static int elants_i2c_fw_update(struct elants_data *ts)
 793 {
 794         struct i2c_client *client = ts->client;
 795         const struct firmware *fw;
 796         char *fw_name;
 797         int error;
 798
 799         fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
 800         if (!fw_name)
 801                 return -ENOMEM;
 802
 803         dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
 804         error = request_firmware(&fw, fw_name, &client->dev);
 805         kfree(fw_name);
 806         if (error) {
 807                 dev_err(&client->dev, "failed to request firmware: %d\n",
 808                         error);
 809                 return error;
 810         }
 811
 812         if (fw->size % ELAN_FW_PAGESIZE) {
 813                 dev_err(&client->dev, "invalid firmware length: %zu\n",
 814                         fw->size);
 815                 error = -EINVAL;
 816                 goto out;
 817         }
 818
 819         disable_irq(client->irq);
 820
 821         error = elants_i2c_do_update_firmware(client, fw,
 822                                         ts->iap_mode == ELAN_IAP_RECOVERY);
 823         if (error) {
 824                 dev_err(&client->dev, "firmware update failed: %d\n", error);
 825                 ts->iap_mode = ELAN_IAP_RECOVERY;
 826                 goto out_enable_irq;
 827         }
 828
 829         error = elants_i2c_initialize(ts);
 830         if (error) {
 831                 dev_err(&client->dev,
 832                         "failed to initialize device after firmware update: %d\n",
 833                         error);
 834                 ts->iap_mode = ELAN_IAP_RECOVERY;
 835                 goto out_enable_irq;
 836         }
 837
 838         ts->iap_mode = ELAN_IAP_OPERATIONAL;
 839
 840 out_enable_irq:
 841         ts->state = ELAN_STATE_NORMAL;
 842         enable_irq(client->irq);
 843         msleep(100);
 844
 845         if (!error)
 846                 elants_i2c_calibrate(ts);
 847 out:
 848         release_firmware(fw);
 849         return error;
 850 }
 851
 852 /*
 853  * Event reporting.
 854  */
 855
 856 static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
 857 {
 858         struct input_dev *input = ts->input;
 859         unsigned int n_fingers;
 860         unsigned int tool_type;
 861         u16 finger_state;
 862         int i;
 863
 864         n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
 865         finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
 866                         buf[FW_POS_STATE];
 867
 868         dev_dbg(&ts->client->dev,
 869                 "n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
 870
 871         /* Note: all fingers have the same tool type */
 872         tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
 873                         MT_TOOL_FINGER : MT_TOOL_PALM;
 874
 875         for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
 876                 if (finger_state & 1) {
 877                         unsigned int x, y, p, w;
 878                         u8 *pos;
 879
 880                         pos = &buf[FW_POS_XY + i * 3];
 881                         x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
 882                         y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
 883                         p = buf[FW_POS_PRESSURE + i];
 884                         w = buf[FW_POS_WIDTH + i];
 885
 886                         dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
 887                                 i, x, y, p, w);
 888
 889                         input_mt_slot(input, i);
 890                         input_mt_report_slot_state(input, tool_type, true);
 891                         touchscreen_report_pos(input, &ts->prop, x, y, true);
 892                         input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
 893                         input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
 894
 895                         n_fingers--;
 896                 }
 897
 898                 finger_state >>= 1;
 899         }
 900
 901         input_mt_sync_frame(input);
 902         input_sync(input);
 903 }
 904
 905 static u8 elants_i2c_calculate_checksum(u8 *buf)
 906 {
 907         u8 checksum = 0;
 908         u8 i;
 909
 910         for (i = 0; i < FW_POS_CHECKSUM; i++)
 911                 checksum += buf[i];
 912
 913         return checksum;
 914 }
 915
 916 static void elants_i2c_event(struct elants_data *ts, u8 *buf)
 917 {
 918         u8 checksum = elants_i2c_calculate_checksum(buf);
 919
 920         if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
 921                 dev_warn(&ts->client->dev,
 922                          "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
 923                          __func__, buf[FW_POS_HEADER],
 924                          checksum, buf[FW_POS_CHECKSUM]);
 925         else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
 926                 dev_warn(&ts->client->dev,
 927                          "%s: unknown packet type: %02x\n",
 928                          __func__, buf[FW_POS_HEADER]);
 929         else
 930                 elants_i2c_mt_event(ts, buf);
 931 }
 932
 933 static irqreturn_t elants_i2c_irq(int irq, void *_dev)
 934 {
 935         const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
 936         struct elants_data *ts = _dev;
 937         struct i2c_client *client = ts->client;
 938         int report_count, report_len;
 939         int i;
 940         int len;
 941
 942         len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
 943         if (len < 0) {
 944                 dev_err(&client->dev, "%s: failed to read data: %d\n",
 945                         __func__, len);
 946                 goto out;
 947         }
 948
 949         dev_dbg(&client->dev, "%s: packet %*ph\n",
 950                 __func__, HEADER_SIZE, ts->buf);
 951
 952         switch (ts->state) {
 953         case ELAN_WAIT_RECALIBRATION:
 954                 if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
 955                         memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
 956                         complete(&ts->cmd_done);
 957                         ts->state = ELAN_STATE_NORMAL;
 958                 }
 959                 break;
 960
 961         case ELAN_WAIT_QUEUE_HEADER:
 962                 if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
 963                         break;
 964
 965                 ts->state = ELAN_STATE_NORMAL;
 966                 fallthrough;
 967
 968         case ELAN_STATE_NORMAL:
 969
 970                 switch (ts->buf[FW_HDR_TYPE]) {
 971                 case CMD_HEADER_HELLO:
 972                 case CMD_HEADER_RESP:
 973                 case CMD_HEADER_REK:
 974                         break;
 975
 976                 case QUEUE_HEADER_WAIT:
 977                         if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
 978                                 dev_err(&client->dev,
 979                                         "invalid wait packet %*ph\n",
 980                                         HEADER_SIZE, ts->buf);
 981                         } else {
 982                                 ts->state = ELAN_WAIT_QUEUE_HEADER;
 983                                 udelay(30);
 984                         }
 985                         break;
 986
 987                 case QUEUE_HEADER_SINGLE:
 988                         elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
 989                         break;
 990
 991                 case QUEUE_HEADER_NORMAL:
 992                         report_count = ts->buf[FW_HDR_COUNT];
 993                         if (report_count == 0 || report_count > 3) {
 994                                 dev_err(&client->dev,
 995                                         "bad report count: %*ph\n",
 996                                         HEADER_SIZE, ts->buf);
 997                                 break;
 998                         }
 999
1000                         report_len = ts->buf[FW_HDR_LENGTH] / report_count;
1001                         if (report_len != PACKET_SIZE) {
1002                                 dev_err(&client->dev,
1003                                         "mismatching report length: %*ph\n",
1004                                         HEADER_SIZE, ts->buf);
1005                                 break;
1006                         }
1007
1008                         for (i = 0; i < report_count; i++) {
1009                                 u8 *buf = ts->buf + HEADER_SIZE +
1010                                                         i * PACKET_SIZE;
1011                                 elants_i2c_event(ts, buf);
1012                         }
1013                         break;
1014
1015                 default:
1016                         dev_err(&client->dev, "unknown packet %*ph\n",
1017                                 HEADER_SIZE, ts->buf);
1018                         break;
1019                 }
1020                 break;
1021         }
1022
1023 out:
1024         return IRQ_HANDLED;
1025 }
1026
1027 /*
1028  * sysfs interface
1029  */
1030 static ssize_t calibrate_store(struct device *dev,
1031                                struct device_attribute *attr,
1032                                const char *buf, size_t count)
1033 {
1034         struct i2c_client *client = to_i2c_client(dev);
1035         struct elants_data *ts = i2c_get_clientdata(client);
1036         int error;
1037
1038         error = mutex_lock_interruptible(&ts->sysfs_mutex);
1039         if (error)
1040                 return error;
1041
1042         error = elants_i2c_calibrate(ts);
1043
1044         mutex_unlock(&ts->sysfs_mutex);
1045         return error ?: count;
1046 }
1047
1048 static ssize_t write_update_fw(struct device *dev,
1049                                struct device_attribute *attr,
1050                                const char *buf, size_t count)
1051 {
1052         struct i2c_client *client = to_i2c_client(dev);
1053         struct elants_data *ts = i2c_get_clientdata(client);
1054         int error;
1055
1056         error = mutex_lock_interruptible(&ts->sysfs_mutex);
1057         if (error)
1058                 return error;
1059
1060         error = elants_i2c_fw_update(ts);
1061         dev_dbg(dev, "firmware update result: %d\n", error);
1062
1063         mutex_unlock(&ts->sysfs_mutex);
1064         return error ?: count;
1065 }
1066
1067 static ssize_t show_iap_mode(struct device *dev,
1068                              struct device_attribute *attr, char *buf)
1069 {
1070         struct i2c_client *client = to_i2c_client(dev);
1071         struct elants_data *ts = i2c_get_clientdata(client);
1072
1073         return sprintf(buf, "%s\n",
1074                        ts->iap_mode == ELAN_IAP_OPERATIONAL ?
1075                                 "Normal" : "Recovery");
1076 }
1077
1078 static ssize_t show_calibration_count(struct device *dev,
1079                                       struct device_attribute *attr, char *buf)
1080 {
1081         struct i2c_client *client = to_i2c_client(dev);
1082         const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
1083         u8 resp[HEADER_SIZE];
1084         u16 rek_count;
1085         int error;
1086
1087         error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
1088                                            resp, sizeof(resp), 1,
1089                                            "read ReK status");
1090         if (error)
1091                 return sprintf(buf, "%d\n", error);
1092
1093         rek_count = get_unaligned_be16(&resp[2]);
1094         return sprintf(buf, "0x%04x\n", rek_count);
1095 }
1096
1097 static DEVICE_ATTR_WO(calibrate);
1098 static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
1099 static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
1100 static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
1101
1102 struct elants_version_attribute {
1103         struct device_attribute dattr;
1104         size_t field_offset;
1105         size_t field_size;
1106 };
1107
1108 #define __ELANTS_FIELD_SIZE(_field)                                     \
1109         sizeof(((struct elants_data *)NULL)->_field)
1110 #define __ELANTS_VERIFY_SIZE(_field)                                    \
1111         (BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +           \
1112          __ELANTS_FIELD_SIZE(_field))
1113 #define ELANTS_VERSION_ATTR(_field)                                     \
1114         struct elants_version_attribute elants_ver_attr_##_field = {    \
1115                 .dattr = __ATTR(_field, S_IRUGO,                        \
1116                                 elants_version_attribute_show, NULL),   \
1117                 .field_offset = offsetof(struct elants_data, _field),   \
1118                 .field_size = __ELANTS_VERIFY_SIZE(_field),             \
1119         }
1120
1121 static ssize_t elants_version_attribute_show(struct device *dev,
1122                                              struct device_attribute *dattr,
1123                                              char *buf)
1124 {
1125         struct i2c_client *client = to_i2c_client(dev);
1126         struct elants_data *ts = i2c_get_clientdata(client);
1127         struct elants_version_attribute *attr =
1128                 container_of(dattr, struct elants_version_attribute, dattr);
1129         u8 *field = (u8 *)((char *)ts + attr->field_offset);
1130         unsigned int fmt_size;
1131         unsigned int val;
1132
1133         if (attr->field_size == 1) {
1134                 val = *field;
1135                 fmt_size = 2; /* 2 HEX digits */
1136         } else {
1137                 val = *(u16 *)field;
1138                 fmt_size = 4; /* 4 HEX digits */
1139         }
1140
1141         return sprintf(buf, "%0*x\n", fmt_size, val);
1142 }
1143
1144 static ELANTS_VERSION_ATTR(fw_version);
1145 static ELANTS_VERSION_ATTR(hw_version);
1146 static ELANTS_VERSION_ATTR(test_version);
1147 static ELANTS_VERSION_ATTR(solution_version);
1148 static ELANTS_VERSION_ATTR(bc_version);
1149 static ELANTS_VERSION_ATTR(iap_version);
1150
1151 static struct attribute *elants_attributes[] = {
1152         &dev_attr_calibrate.attr,
1153         &dev_attr_update_fw.attr,
1154         &dev_attr_iap_mode.attr,
1155         &dev_attr_calibration_count.attr,
1156
1157         &elants_ver_attr_fw_version.dattr.attr,
1158         &elants_ver_attr_hw_version.dattr.attr,
1159         &elants_ver_attr_test_version.dattr.attr,
1160         &elants_ver_attr_solution_version.dattr.attr,
1161         &elants_ver_attr_bc_version.dattr.attr,
1162         &elants_ver_attr_iap_version.dattr.attr,
1163         NULL
1164 };
1165
1166 static const struct attribute_group elants_attribute_group = {
1167         .attrs = elants_attributes,
1168 };
1169
1170 static int elants_i2c_power_on(struct elants_data *ts)
1171 {
1172         int error;
1173
1174         /*
1175          * If we do not have reset gpio assume platform firmware
1176          * controls regulators and does power them on for us.
1177          */
1178         if (IS_ERR_OR_NULL(ts->reset_gpio))
1179                 return 0;
1180
1181         gpiod_set_value_cansleep(ts->reset_gpio, 1);
1182
1183         error = regulator_enable(ts->vcc33);
1184         if (error) {
1185                 dev_err(&ts->client->dev,
1186                         "failed to enable vcc33 regulator: %d\n",
1187                         error);
1188                 goto release_reset_gpio;
1189         }
1190
1191         error = regulator_enable(ts->vccio);
1192         if (error) {
1193                 dev_err(&ts->client->dev,
1194                         "failed to enable vccio regulator: %d\n",
1195                         error);
1196                 regulator_disable(ts->vcc33);
1197                 goto release_reset_gpio;
1198         }
1199
1200         /*
1201          * We need to wait a bit after powering on controller before
1202          * we are allowed to release reset GPIO.
1203          */
1204         udelay(ELAN_POWERON_DELAY_USEC);
1205
1206 release_reset_gpio:
1207         gpiod_set_value_cansleep(ts->reset_gpio, 0);
1208         if (error)
1209                 return error;
1210
1211         msleep(ELAN_RESET_DELAY_MSEC);
1212
1213         return 0;
1214 }
1215
1216 static void elants_i2c_power_off(void *_data)
1217 {
1218         struct elants_data *ts = _data;
1219
1220         if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
1221                 /*
1222                  * Activate reset gpio to prevent leakage through the
1223                  * pin once we shut off power to the controller.
1224                  */
1225                 gpiod_set_value_cansleep(ts->reset_gpio, 1);
1226                 regulator_disable(ts->vccio);
1227                 regulator_disable(ts->vcc33);
1228         }
1229 }
1230
1231 static int elants_i2c_probe(struct i2c_client *client,
1232                             const struct i2c_device_id *id)
1233 {
1234         union i2c_smbus_data dummy;
1235         struct elants_data *ts;
1236         unsigned long irqflags;
1237         int error;
1238
1239         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1240                 dev_err(&client->dev,
1241                         "%s: i2c check functionality error\n", DEVICE_NAME);
1242                 return -ENXIO;
1243         }
1244
1245         ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
1246         if (!ts)
1247                 return -ENOMEM;
1248
1249         mutex_init(&ts->sysfs_mutex);
1250         init_completion(&ts->cmd_done);
1251
1252         ts->client = client;
1253         i2c_set_clientdata(client, ts);
1254
1255         ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
1256         if (IS_ERR(ts->vcc33)) {
1257                 error = PTR_ERR(ts->vcc33);
1258                 if (error != -EPROBE_DEFER)
1259                         dev_err(&client->dev,
1260                                 "Failed to get 'vcc33' regulator: %d\n",
1261                                 error);
1262                 return error;
1263         }
1264
1265         ts->vccio = devm_regulator_get(&client->dev, "vccio");
1266         if (IS_ERR(ts->vccio)) {
1267                 error = PTR_ERR(ts->vccio);
1268                 if (error != -EPROBE_DEFER)
1269                         dev_err(&client->dev,
1270                                 "Failed to get 'vccio' regulator: %d\n",
1271                                 error);
1272                 return error;
1273         }
1274
1275         ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
1276         if (IS_ERR(ts->reset_gpio)) {
1277                 error = PTR_ERR(ts->reset_gpio);
1278
1279                 if (error == -EPROBE_DEFER)
1280                         return error;
1281
1282                 if (error != -ENOENT && error != -ENOSYS) {
1283                         dev_err(&client->dev,
1284                                 "failed to get reset gpio: %d\n",
1285                                 error);
1286                         return error;
1287                 }
1288
1289                 ts->keep_power_in_suspend = true;
1290         }
1291
1292         error = elants_i2c_power_on(ts);
1293         if (error)
1294                 return error;
1295
1296         error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
1297         if (error) {
1298                 dev_err(&client->dev,
1299                         "failed to install power off action: %d\n", error);
1300                 elants_i2c_power_off(ts);
1301                 return error;
1302         }
1303
1304         /* Make sure there is something at this address */
1305         if (i2c_smbus_xfer(client->adapter, client->addr, 0,
1306                            I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
1307                 dev_err(&client->dev, "nothing at this address\n");
1308                 return -ENXIO;
1309         }
1310
1311         error = elants_i2c_initialize(ts);
1312         if (error) {
1313                 dev_err(&client->dev, "failed to initialize: %d\n", error);
1314                 return error;
1315         }
1316
1317         ts->input = devm_input_allocate_device(&client->dev);
1318         if (!ts->input) {
1319                 dev_err(&client->dev, "Failed to allocate input device\n");
1320                 return -ENOMEM;
1321         }
1322
1323         ts->input->name = "Elan Touchscreen";
1324         ts->input->id.bustype = BUS_I2C;
1325
1326         /* Multitouch input params setup */
1327
1328         input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
1329         input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
1330         input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
1331         input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
1332         input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
1333                              0, MT_TOOL_PALM, 0, 0);
1334         input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
1335         input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
1336         if (ts->major_res > 0)
1337                 input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->major_res);
1338
1339         touchscreen_parse_properties(ts->input, true, &ts->prop);
1340
1341         error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
1342                                     INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1343         if (error) {
1344                 dev_err(&client->dev,
1345                         "failed to initialize MT slots: %d\n", error);
1346                 return error;
1347         }
1348
1349         error = input_register_device(ts->input);
1350         if (error) {
1351                 dev_err(&client->dev,
1352                         "unable to register input device: %d\n", error);
1353                 return error;
1354         }
1355
1356         /*
1357          * Platform code (ACPI, DTS) should normally set up interrupt
1358          * for us, but in case it did not let's fall back to using falling
1359          * edge to be compatible with older Chromebooks.
1360          */
1361         irqflags = irq_get_trigger_type(client->irq);
1362         if (!irqflags)
1363                 irqflags = IRQF_TRIGGER_FALLING;
1364
1365         error = devm_request_threaded_irq(&client->dev, client->irq,
1366                                           NULL, elants_i2c_irq,
1367                                           irqflags | IRQF_ONESHOT,
1368                                           client->name, ts);
1369         if (error) {
1370                 dev_err(&client->dev, "Failed to register interrupt\n");
1371                 return error;
1372         }
1373
1374         /*
1375          * Systems using device tree should set up wakeup via DTS,
1376          * the rest will configure device as wakeup source by default.
1377          */
1378         if (!client->dev.of_node)
1379                 device_init_wakeup(&client->dev, true);
1380
1381         error = devm_device_add_group(&client->dev, &elants_attribute_group);
1382         if (error) {
1383                 dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
1384                         error);
1385                 return error;
1386         }
1387
1388         return 0;
1389 }
1390
1391 static int __maybe_unused elants_i2c_suspend(struct device *dev)
1392 {
1393         struct i2c_client *client = to_i2c_client(dev);
1394         struct elants_data *ts = i2c_get_clientdata(client);
1395         const u8 set_sleep_cmd[] = {
1396                 CMD_HEADER_WRITE, E_POWER_STATE_SLEEP, 0x00, 0x01
1397         };
1398         int retry_cnt;
1399         int error;
1400
1401         /* Command not support in IAP recovery mode */
1402         if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
1403                 return -EBUSY;
1404
1405         disable_irq(client->irq);
1406
1407         if (device_may_wakeup(dev)) {
1408                 /*
1409                  * The device will automatically enter idle mode
1410                  * that has reduced power consumption.
1411                  */
1412                 ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
1413         } else if (ts->keep_power_in_suspend) {
1414                 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1415                         error = elants_i2c_send(client, set_sleep_cmd,
1416                                                 sizeof(set_sleep_cmd));
1417                         if (!error)
1418                                 break;
1419
1420                         dev_err(&client->dev,
1421                                 "suspend command failed: %d\n", error);
1422                 }
1423         } else {
1424                 elants_i2c_power_off(ts);
1425         }
1426
1427         return 0;
1428 }
1429
1430 static int __maybe_unused elants_i2c_resume(struct device *dev)
1431 {
1432         struct i2c_client *client = to_i2c_client(dev);
1433         struct elants_data *ts = i2c_get_clientdata(client);
1434         const u8 set_active_cmd[] = {
1435                 CMD_HEADER_WRITE, E_POWER_STATE_RESUME, 0x00, 0x01
1436         };
1437         int retry_cnt;
1438         int error;
1439
1440         if (device_may_wakeup(dev)) {
1441                 if (ts->wake_irq_enabled)
1442                         disable_irq_wake(client->irq);
1443                 elants_i2c_sw_reset(client);
1444         } else if (ts->keep_power_in_suspend) {
1445                 for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
1446                         error = elants_i2c_send(client, set_active_cmd,
1447                                                 sizeof(set_active_cmd));
1448                         if (!error)
1449                                 break;
1450
1451                         dev_err(&client->dev,
1452                                 "resume command failed: %d\n", error);
1453                 }
1454         } else {
1455                 elants_i2c_power_on(ts);
1456                 elants_i2c_initialize(ts);
1457         }
1458
1459         ts->state = ELAN_STATE_NORMAL;
1460         enable_irq(client->irq);
1461
1462         return 0;
1463 }
1464
1465 static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
1466                          elants_i2c_suspend, elants_i2c_resume);
1467
1468 static const struct i2c_device_id elants_i2c_id[] = {
1469         { DEVICE_NAME, 0 },
1470         { }
1471 };
1472 MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
1473
1474 #ifdef CONFIG_ACPI
1475 static const struct acpi_device_id elants_acpi_id[] = {
1476         { "ELAN0001", 0 },
1477         { }
1478 };
1479 MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
1480 #endif
1481
1482 #ifdef CONFIG_OF
1483 static const struct of_device_id elants_of_match[] = {
1484         { .compatible = "elan,ekth3500" },
1485         { /* sentinel */ }
1486 };
1487 MODULE_DEVICE_TABLE(of, elants_of_match);
1488 #endif
1489
1490 static struct i2c_driver elants_i2c_driver = {
1491         .probe = elants_i2c_probe,
1492         .id_table = elants_i2c_id,
1493         .driver = {
1494                 .name = DEVICE_NAME,
1495                 .pm = &elants_i2c_pm_ops,
1496                 .acpi_match_table = ACPI_PTR(elants_acpi_id),
1497                 .of_match_table = of_match_ptr(elants_of_match),
1498                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1499         },
1500 };
1501 module_i2c_driver(elants_i2c_driver);
1502
1503 MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
1504 MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
1505 MODULE_LICENSE("GPL");