drivers/input/mouse/elan_i2c_i2c.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Elan I2C/SMBus Touchpad driver - I2C interface
   4  *
   5  * Copyright (c) 2013 ELAN Microelectronics Corp.
   6  *
   7  * Author: 林政維 (Duson Lin) <dusonlin@emc.com.tw>
   8  *
   9  * Based on cyapa driver:
  10  * copyright (c) 2011-2012 Cypress Semiconductor, Inc.
  11  * copyright (c) 2011-2012 Google, Inc.
  12  *
  13  * Trademarks are the property of their respective owners.
  14  */
  15
  16 #include <linux/completion.h>
  17 #include <linux/delay.h>
  18 #include <linux/i2c.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/jiffies.h>
  21 #include <linux/kernel.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <asm/unaligned.h>
  25
  26 #include "elan_i2c.h"
  27
  28 /* Elan i2c commands */
  29 #define ETP_I2C_RESET                   0x0100
  30 #define ETP_I2C_WAKE_UP                 0x0800
  31 #define ETP_I2C_SLEEP                   0x0801
  32 #define ETP_I2C_DESC_CMD                0x0001
  33 #define ETP_I2C_REPORT_DESC_CMD         0x0002
  34 #define ETP_I2C_STAND_CMD               0x0005
  35 #define ETP_I2C_PATTERN_CMD             0x0100
  36 #define ETP_I2C_UNIQUEID_CMD            0x0101
  37 #define ETP_I2C_FW_VERSION_CMD          0x0102
  38 #define ETP_I2C_IC_TYPE_CMD             0x0103
  39 #define ETP_I2C_OSM_VERSION_CMD         0x0103
  40 #define ETP_I2C_NSM_VERSION_CMD         0x0104
  41 #define ETP_I2C_XY_TRACENUM_CMD         0x0105
  42 #define ETP_I2C_MAX_X_AXIS_CMD          0x0106
  43 #define ETP_I2C_MAX_Y_AXIS_CMD          0x0107
  44 #define ETP_I2C_RESOLUTION_CMD          0x0108
  45 #define ETP_I2C_PRESSURE_CMD            0x010A
  46 #define ETP_I2C_IAP_VERSION_CMD         0x0110
  47 #define ETP_I2C_IC_TYPE_P0_CMD          0x0110
  48 #define ETP_I2C_IAP_VERSION_P0_CMD      0x0111
  49 #define ETP_I2C_SET_CMD                 0x0300
  50 #define ETP_I2C_POWER_CMD               0x0307
  51 #define ETP_I2C_FW_CHECKSUM_CMD         0x030F
  52 #define ETP_I2C_IAP_CTRL_CMD            0x0310
  53 #define ETP_I2C_IAP_CMD                 0x0311
  54 #define ETP_I2C_IAP_RESET_CMD           0x0314
  55 #define ETP_I2C_IAP_CHECKSUM_CMD        0x0315
  56 #define ETP_I2C_CALIBRATE_CMD           0x0316
  57 #define ETP_I2C_MAX_BASELINE_CMD        0x0317
  58 #define ETP_I2C_MIN_BASELINE_CMD        0x0318
  59 #define ETP_I2C_IAP_TYPE_REG            0x0040
  60 #define ETP_I2C_IAP_TYPE_CMD            0x0304
  61
  62 #define ETP_I2C_REPORT_LEN              34
  63 #define ETP_I2C_DESC_LENGTH             30
  64 #define ETP_I2C_REPORT_DESC_LENGTH      158
  65 #define ETP_I2C_INF_LENGTH              2
  66 #define ETP_I2C_IAP_PASSWORD            0x1EA5
  67 #define ETP_I2C_IAP_RESET               0xF0F0
  68 #define ETP_I2C_MAIN_MODE_ON            (1 << 9)
  69 #define ETP_I2C_IAP_REG_L               0x01
  70 #define ETP_I2C_IAP_REG_H               0x06
  71
  72 static int elan_i2c_read_block(struct i2c_client *client,
  73                                u16 reg, u8 *val, u16 len)
  74 {
  75         __le16 buf[] = {
  76                 cpu_to_le16(reg),
  77         };
  78         struct i2c_msg msgs[] = {
  79                 {
  80                         .addr = client->addr,
  81                         .flags = client->flags & I2C_M_TEN,
  82                         .len = sizeof(buf),
  83                         .buf = (u8 *)buf,
  84                 },
  85                 {
  86                         .addr = client->addr,
  87                         .flags = (client->flags & I2C_M_TEN) | I2C_M_RD,
  88                         .len = len,
  89                         .buf = val,
  90                 }
  91         };
  92         int ret;
  93
  94         ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  95         return ret == ARRAY_SIZE(msgs) ? 0 : (ret < 0 ? ret : -EIO);
  96 }
  97
  98 static int elan_i2c_read_cmd(struct i2c_client *client, u16 reg, u8 *val)
  99 {
 100         int retval;
 101
 102         retval = elan_i2c_read_block(client, reg, val, ETP_I2C_INF_LENGTH);
 103         if (retval < 0) {
 104                 dev_err(&client->dev, "reading cmd (0x%04x) fail.\n", reg);
 105                 return retval;
 106         }
 107
 108         return 0;
 109 }
 110
 111 static int elan_i2c_write_cmd(struct i2c_client *client, u16 reg, u16 cmd)
 112 {
 113         __le16 buf[] = {
 114                 cpu_to_le16(reg),
 115                 cpu_to_le16(cmd),
 116         };
 117         struct i2c_msg msg = {
 118                 .addr = client->addr,
 119                 .flags = client->flags & I2C_M_TEN,
 120                 .len = sizeof(buf),
 121                 .buf = (u8 *)buf,
 122         };
 123         int ret;
 124
 125         ret = i2c_transfer(client->adapter, &msg, 1);
 126         if (ret != 1) {
 127                 if (ret >= 0)
 128                         ret = -EIO;
 129                 dev_err(&client->dev, "writing cmd (0x%04x) failed: %d\n",
 130                         reg, ret);
 131                 return ret;
 132         }
 133
 134         return 0;
 135 }
 136
 137 static int elan_i2c_initialize(struct i2c_client *client)
 138 {
 139         struct device *dev = &client->dev;
 140         int error;
 141         u8 val[256];
 142
 143         error = elan_i2c_write_cmd(client, ETP_I2C_STAND_CMD, ETP_I2C_RESET);
 144         if (error) {
 145                 dev_err(dev, "device reset failed: %d\n", error);
 146                 return error;
 147         }
 148
 149         /* Wait for the device to reset */
 150         msleep(100);
 151
 152         /* get reset acknowledgement 0000 */
 153         error = i2c_master_recv(client, val, ETP_I2C_INF_LENGTH);
 154         if (error < 0) {
 155                 dev_err(dev, "failed to read reset response: %d\n", error);
 156                 return error;
 157         }
 158
 159         error = elan_i2c_read_block(client, ETP_I2C_DESC_CMD,
 160                                     val, ETP_I2C_DESC_LENGTH);
 161         if (error) {
 162                 dev_err(dev, "cannot get device descriptor: %d\n", error);
 163                 return error;
 164         }
 165
 166         error = elan_i2c_read_block(client, ETP_I2C_REPORT_DESC_CMD,
 167                                     val, ETP_I2C_REPORT_DESC_LENGTH);
 168         if (error) {
 169                 dev_err(dev, "fetching report descriptor failed.: %d\n", error);
 170                 return error;
 171         }
 172
 173         return 0;
 174 }
 175
 176 static int elan_i2c_sleep_control(struct i2c_client *client, bool sleep)
 177 {
 178         return elan_i2c_write_cmd(client, ETP_I2C_STAND_CMD,
 179                                   sleep ? ETP_I2C_SLEEP : ETP_I2C_WAKE_UP);
 180 }
 181
 182 static int elan_i2c_power_control(struct i2c_client *client, bool enable)
 183 {
 184         u8 val[2];
 185         u16 reg;
 186         int error;
 187
 188         error = elan_i2c_read_cmd(client, ETP_I2C_POWER_CMD, val);
 189         if (error) {
 190                 dev_err(&client->dev,
 191                         "failed to read current power state: %d\n",
 192                         error);
 193                 return error;
 194         }
 195
 196         reg = le16_to_cpup((__le16 *)val);
 197         if (enable)
 198                 reg &= ~ETP_DISABLE_POWER;
 199         else
 200                 reg |= ETP_DISABLE_POWER;
 201
 202         error = elan_i2c_write_cmd(client, ETP_I2C_POWER_CMD, reg);
 203         if (error) {
 204                 dev_err(&client->dev,
 205                         "failed to write current power state: %d\n",
 206                         error);
 207                 return error;
 208         }
 209
 210         return 0;
 211 }
 212
 213 static int elan_i2c_set_mode(struct i2c_client *client, u8 mode)
 214 {
 215         return elan_i2c_write_cmd(client, ETP_I2C_SET_CMD, mode);
 216 }
 217
 218
 219 static int elan_i2c_calibrate(struct i2c_client *client)
 220 {
 221         return elan_i2c_write_cmd(client, ETP_I2C_CALIBRATE_CMD, 1);
 222 }
 223
 224 static int elan_i2c_calibrate_result(struct i2c_client *client, u8 *val)
 225 {
 226         return elan_i2c_read_block(client, ETP_I2C_CALIBRATE_CMD, val, 1);
 227 }
 228
 229 static int elan_i2c_get_baseline_data(struct i2c_client *client,
 230                                       bool max_baseline, u8 *value)
 231 {
 232         int error;
 233         u8 val[3];
 234
 235         error = elan_i2c_read_cmd(client,
 236                                   max_baseline ? ETP_I2C_MAX_BASELINE_CMD :
 237                                                  ETP_I2C_MIN_BASELINE_CMD,
 238                                   val);
 239         if (error)
 240                 return error;
 241
 242         *value = le16_to_cpup((__le16 *)val);
 243
 244         return 0;
 245 }
 246
 247 static int elan_i2c_get_pattern(struct i2c_client *client, u8 *pattern)
 248 {
 249         int error;
 250         u8 val[3];
 251
 252         error = elan_i2c_read_cmd(client, ETP_I2C_PATTERN_CMD, val);
 253         if (error) {
 254                 dev_err(&client->dev, "failed to get pattern: %d\n", error);
 255                 return error;
 256         }
 257
 258         /*
 259          * Not all versions of firmware implement "get pattern" command.
 260          * When this command is not implemented the device will respond
 261          * with 0xFF 0xFF, which we will treat as "old" pattern 0.
 262          */
 263         *pattern = val[0] == 0xFF && val[1] == 0xFF ? 0 : val[1];
 264
 265         return 0;
 266 }
 267
 268 static int elan_i2c_get_version(struct i2c_client *client,
 269                                 u8 pattern, bool iap, u8 *version)
 270 {
 271         int error;
 272         u16 cmd;
 273         u8 val[3];
 274
 275         if (!iap)
 276                 cmd = ETP_I2C_FW_VERSION_CMD;
 277         else if (pattern == 0)
 278                 cmd = ETP_I2C_IAP_VERSION_P0_CMD;
 279         else
 280                 cmd = ETP_I2C_IAP_VERSION_CMD;
 281
 282         error = elan_i2c_read_cmd(client, cmd, val);
 283         if (error) {
 284                 dev_err(&client->dev, "failed to get %s version: %d\n",
 285                         iap ? "IAP" : "FW", error);
 286                 return error;
 287         }
 288
 289         if (pattern >= 0x01)
 290                 *version = iap ? val[1] : val[0];
 291         else
 292                 *version = val[0];
 293         return 0;
 294 }
 295
 296 static int elan_i2c_get_sm_version(struct i2c_client *client, u8 pattern,
 297                                    u16 *ic_type, u8 *version, u8 *clickpad)
 298 {
 299         int error;
 300         u8 val[3];
 301
 302         if (pattern >= 0x01) {
 303                 error = elan_i2c_read_cmd(client, ETP_I2C_IC_TYPE_CMD, val);
 304                 if (error) {
 305                         dev_err(&client->dev, "failed to get ic type: %d\n",
 306                                 error);
 307                         return error;
 308                 }
 309                 *ic_type = be16_to_cpup((__be16 *)val);
 310
 311                 error = elan_i2c_read_cmd(client, ETP_I2C_NSM_VERSION_CMD,
 312                                           val);
 313                 if (error) {
 314                         dev_err(&client->dev, "failed to get SM version: %d\n",
 315                                 error);
 316                         return error;
 317                 }
 318                 *version = val[1];
 319                 *clickpad = val[0] & 0x10;
 320         } else {
 321                 error = elan_i2c_read_cmd(client, ETP_I2C_OSM_VERSION_CMD, val);
 322                 if (error) {
 323                         dev_err(&client->dev, "failed to get SM version: %d\n",
 324                                 error);
 325                         return error;
 326                 }
 327                 *version = val[0];
 328
 329                 error = elan_i2c_read_cmd(client, ETP_I2C_IC_TYPE_P0_CMD, val);
 330                 if (error) {
 331                         dev_err(&client->dev, "failed to get ic type: %d\n",
 332                                 error);
 333                         return error;
 334                 }
 335                 *ic_type = val[0];
 336
 337                 error = elan_i2c_read_cmd(client, ETP_I2C_NSM_VERSION_CMD,
 338                                           val);
 339                 if (error) {
 340                         dev_err(&client->dev, "failed to get SM version: %d\n",
 341                                 error);
 342                         return error;
 343                 }
 344                 *clickpad = val[0] & 0x10;
 345         }
 346
 347         return 0;
 348 }
 349
 350 static int elan_i2c_get_product_id(struct i2c_client *client, u16 *id)
 351 {
 352         int error;
 353         u8 val[3];
 354
 355         error = elan_i2c_read_cmd(client, ETP_I2C_UNIQUEID_CMD, val);
 356         if (error) {
 357                 dev_err(&client->dev, "failed to get product ID: %d\n", error);
 358                 return error;
 359         }
 360
 361         *id = le16_to_cpup((__le16 *)val);
 362         return 0;
 363 }
 364
 365 static int elan_i2c_get_checksum(struct i2c_client *client,
 366                                  bool iap, u16 *csum)
 367 {
 368         int error;
 369         u8 val[3];
 370
 371         error = elan_i2c_read_cmd(client,
 372                                   iap ? ETP_I2C_IAP_CHECKSUM_CMD :
 373                                         ETP_I2C_FW_CHECKSUM_CMD,
 374                                   val);
 375         if (error) {
 376                 dev_err(&client->dev, "failed to get %s checksum: %d\n",
 377                         iap ? "IAP" : "FW", error);
 378                 return error;
 379         }
 380
 381         *csum = le16_to_cpup((__le16 *)val);
 382         return 0;
 383 }
 384
 385 static int elan_i2c_get_max(struct i2c_client *client,
 386                             unsigned int *max_x, unsigned int *max_y)
 387 {
 388         int error;
 389         u8 val[3];
 390
 391         error = elan_i2c_read_cmd(client, ETP_I2C_MAX_X_AXIS_CMD, val);
 392         if (error) {
 393                 dev_err(&client->dev, "failed to get X dimension: %d\n", error);
 394                 return error;
 395         }
 396
 397         *max_x = le16_to_cpup((__le16 *)val) & 0x0fff;
 398
 399         error = elan_i2c_read_cmd(client, ETP_I2C_MAX_Y_AXIS_CMD, val);
 400         if (error) {
 401                 dev_err(&client->dev, "failed to get Y dimension: %d\n", error);
 402                 return error;
 403         }
 404
 405         *max_y = le16_to_cpup((__le16 *)val) & 0x0fff;
 406
 407         return 0;
 408 }
 409
 410 static int elan_i2c_get_resolution(struct i2c_client *client,
 411                                    u8 *hw_res_x, u8 *hw_res_y)
 412 {
 413         int error;
 414         u8 val[3];
 415
 416         error = elan_i2c_read_cmd(client, ETP_I2C_RESOLUTION_CMD, val);
 417         if (error) {
 418                 dev_err(&client->dev, "failed to get resolution: %d\n", error);
 419                 return error;
 420         }
 421
 422         *hw_res_x = val[0];
 423         *hw_res_y = val[1];
 424
 425         return 0;
 426 }
 427
 428 static int elan_i2c_get_num_traces(struct i2c_client *client,
 429                                    unsigned int *x_traces,
 430                                    unsigned int *y_traces)
 431 {
 432         int error;
 433         u8 val[3];
 434
 435         error = elan_i2c_read_cmd(client, ETP_I2C_XY_TRACENUM_CMD, val);
 436         if (error) {
 437                 dev_err(&client->dev, "failed to get trace info: %d\n", error);
 438                 return error;
 439         }
 440
 441         *x_traces = val[0];
 442         *y_traces = val[1];
 443
 444         return 0;
 445 }
 446
 447 static int elan_i2c_get_pressure_adjustment(struct i2c_client *client,
 448                                             int *adjustment)
 449 {
 450         int error;
 451         u8 val[3];
 452
 453         error = elan_i2c_read_cmd(client, ETP_I2C_PRESSURE_CMD, val);
 454         if (error) {
 455                 dev_err(&client->dev, "failed to get pressure format: %d\n",
 456                         error);
 457                 return error;
 458         }
 459
 460         if ((val[0] >> 4) & 0x1)
 461                 *adjustment = 0;
 462         else
 463                 *adjustment = ETP_PRESSURE_OFFSET;
 464
 465         return 0;
 466 }
 467
 468 static int elan_i2c_iap_get_mode(struct i2c_client *client, enum tp_mode *mode)
 469 {
 470         int error;
 471         u16 constant;
 472         u8 val[3];
 473
 474         error = elan_i2c_read_cmd(client, ETP_I2C_IAP_CTRL_CMD, val);
 475         if (error) {
 476                 dev_err(&client->dev,
 477                         "failed to read iap control register: %d\n",
 478                         error);
 479                 return error;
 480         }
 481
 482         constant = le16_to_cpup((__le16 *)val);
 483         dev_dbg(&client->dev, "iap control reg: 0x%04x.\n", constant);
 484
 485         *mode = (constant & ETP_I2C_MAIN_MODE_ON) ? MAIN_MODE : IAP_MODE;
 486
 487         return 0;
 488 }
 489
 490 static int elan_i2c_iap_reset(struct i2c_client *client)
 491 {
 492         int error;
 493
 494         error = elan_i2c_write_cmd(client, ETP_I2C_IAP_RESET_CMD,
 495                                    ETP_I2C_IAP_RESET);
 496         if (error) {
 497                 dev_err(&client->dev, "cannot reset IC: %d\n", error);
 498                 return error;
 499         }
 500
 501         return 0;
 502 }
 503
 504 static int elan_i2c_set_flash_key(struct i2c_client *client)
 505 {
 506         int error;
 507
 508         error = elan_i2c_write_cmd(client, ETP_I2C_IAP_CMD,
 509                                    ETP_I2C_IAP_PASSWORD);
 510         if (error) {
 511                 dev_err(&client->dev, "cannot set flash key: %d\n", error);
 512                 return error;
 513         }
 514
 515         return 0;
 516 }
 517
 518 static int elan_read_write_iap_type(struct i2c_client *client)
 519 {
 520         int error;
 521         u16 constant;
 522         u8 val[3];
 523         int retry = 3;
 524
 525         do {
 526                 error = elan_i2c_write_cmd(client, ETP_I2C_IAP_TYPE_CMD,
 527                                            ETP_I2C_IAP_TYPE_REG);
 528                 if (error) {
 529                         dev_err(&client->dev,
 530                                 "cannot write iap type: %d\n", error);
 531                         return error;
 532                 }
 533
 534                 error = elan_i2c_read_cmd(client, ETP_I2C_IAP_TYPE_CMD, val);
 535                 if (error) {
 536                         dev_err(&client->dev,
 537                                 "failed to read iap type register: %d\n",
 538                                 error);
 539                         return error;
 540                 }
 541                 constant = le16_to_cpup((__le16 *)val);
 542                 dev_dbg(&client->dev, "iap type reg: 0x%04x\n", constant);
 543
 544                 if (constant == ETP_I2C_IAP_TYPE_REG)
 545                         return 0;
 546
 547         } while (--retry > 0);
 548
 549         dev_err(&client->dev, "cannot set iap type\n");
 550         return -EIO;
 551 }
 552
 553 static int elan_i2c_prepare_fw_update(struct i2c_client *client, u16 ic_type,
 554                                       u8 iap_version)
 555 {
 556         struct device *dev = &client->dev;
 557         int error;
 558         enum tp_mode mode;
 559         u8 val[3];
 560         u16 password;
 561
 562         /* Get FW in which mode (IAP_MODE/MAIN_MODE)  */
 563         error = elan_i2c_iap_get_mode(client, &mode);
 564         if (error)
 565                 return error;
 566
 567         if (mode == IAP_MODE) {
 568                 /* Reset IC */
 569                 error = elan_i2c_iap_reset(client);
 570                 if (error)
 571                         return error;
 572
 573                 msleep(30);
 574         }
 575
 576         /* Set flash key*/
 577         error = elan_i2c_set_flash_key(client);
 578         if (error)
 579                 return error;
 580
 581         /* Wait for F/W IAP initialization */
 582         msleep(mode == MAIN_MODE ? 100 : 30);
 583
 584         /* Check if we are in IAP mode or not */
 585         error = elan_i2c_iap_get_mode(client, &mode);
 586         if (error)
 587                 return error;
 588
 589         if (mode == MAIN_MODE) {
 590                 dev_err(dev, "wrong mode: %d\n", mode);
 591                 return -EIO;
 592         }
 593
 594         if (ic_type >= 0x0D && iap_version >= 1) {
 595                 error = elan_read_write_iap_type(client);
 596                 if (error)
 597                         return error;
 598         }
 599
 600         /* Set flash key again */
 601         error = elan_i2c_set_flash_key(client);
 602         if (error)
 603                 return error;
 604
 605         /* Wait for F/W IAP initialization */
 606         msleep(30);
 607
 608         /* read back to check we actually enabled successfully. */
 609         error = elan_i2c_read_cmd(client, ETP_I2C_IAP_CMD, val);
 610         if (error) {
 611                 dev_err(dev, "cannot read iap password: %d\n",
 612                         error);
 613                 return error;
 614         }
 615
 616         password = le16_to_cpup((__le16 *)val);
 617         if (password != ETP_I2C_IAP_PASSWORD) {
 618                 dev_err(dev, "wrong iap password: 0x%X\n", password);
 619                 return -EIO;
 620         }
 621
 622         return 0;
 623 }
 624
 625 static int elan_i2c_write_fw_block(struct i2c_client *client, u16 fw_page_size,
 626                                    const u8 *page, u16 checksum, int idx)
 627 {
 628         struct device *dev = &client->dev;
 629         u8 *page_store;
 630         u8 val[3];
 631         u16 result;
 632         int ret, error;
 633
 634         page_store = kmalloc(fw_page_size + 4, GFP_KERNEL);
 635         if (!page_store)
 636                 return -ENOMEM;
 637
 638         page_store[0] = ETP_I2C_IAP_REG_L;
 639         page_store[1] = ETP_I2C_IAP_REG_H;
 640         memcpy(&page_store[2], page, fw_page_size);
 641         /* recode checksum at last two bytes */
 642         put_unaligned_le16(checksum, &page_store[fw_page_size + 2]);
 643
 644         ret = i2c_master_send(client, page_store, fw_page_size + 4);
 645         if (ret != fw_page_size + 4) {
 646                 error = ret < 0 ? ret : -EIO;
 647                 dev_err(dev, "Failed to write page %d: %d\n", idx, error);
 648                 goto exit;
 649         }
 650
 651         /* Wait for F/W to update one page ROM data. */
 652         msleep(fw_page_size == ETP_FW_PAGE_SIZE_512 ? 50 : 35);
 653
 654         error = elan_i2c_read_cmd(client, ETP_I2C_IAP_CTRL_CMD, val);
 655         if (error) {
 656                 dev_err(dev, "Failed to read IAP write result: %d\n", error);
 657                 goto exit;
 658         }
 659
 660         result = le16_to_cpup((__le16 *)val);
 661         if (result & (ETP_FW_IAP_PAGE_ERR | ETP_FW_IAP_INTF_ERR)) {
 662                 dev_err(dev, "IAP reports failed write: %04hx\n",
 663                         result);
 664                 error = -EIO;
 665                 goto exit;
 666         }
 667
 668 exit:
 669         kfree(page_store);
 670         return error;
 671 }
 672
 673 static int elan_i2c_finish_fw_update(struct i2c_client *client,
 674                                      struct completion *completion)
 675 {
 676         struct device *dev = &client->dev;
 677         int error;
 678         int len;
 679         u8 buffer[ETP_I2C_REPORT_LEN];
 680
 681         len = i2c_master_recv(client, buffer, ETP_I2C_REPORT_LEN);
 682         if (len != ETP_I2C_REPORT_LEN) {
 683                 error = len < 0 ? len : -EIO;
 684                 dev_warn(dev, "failed to read I2C data after FW WDT reset: %d (%d)\n",
 685                         error, len);
 686         }
 687
 688         reinit_completion(completion);
 689         enable_irq(client->irq);
 690
 691         error = elan_i2c_write_cmd(client, ETP_I2C_STAND_CMD, ETP_I2C_RESET);
 692         if (error) {
 693                 dev_err(dev, "device reset failed: %d\n", error);
 694         } else if (!wait_for_completion_timeout(completion,
 695                                                 msecs_to_jiffies(300))) {
 696                 dev_err(dev, "timeout waiting for device reset\n");
 697                 error = -ETIMEDOUT;
 698         }
 699
 700         disable_irq(client->irq);
 701
 702         if (error)
 703                 return error;
 704
 705         len = i2c_master_recv(client, buffer, ETP_I2C_INF_LENGTH);
 706         if (len != ETP_I2C_INF_LENGTH) {
 707                 error = len < 0 ? len : -EIO;
 708                 dev_err(dev, "failed to read INT signal: %d (%d)\n",
 709                         error, len);
 710                 return error;
 711         }
 712
 713         return 0;
 714 }
 715
 716 static int elan_i2c_get_report(struct i2c_client *client, u8 *report)
 717 {
 718         int len;
 719
 720         len = i2c_master_recv(client, report, ETP_I2C_REPORT_LEN);
 721         if (len < 0) {
 722                 dev_err(&client->dev, "failed to read report data: %d\n", len);
 723                 return len;
 724         }
 725
 726         if (len != ETP_I2C_REPORT_LEN) {
 727                 dev_err(&client->dev,
 728                         "wrong report length (%d vs %d expected)\n",
 729                         len, ETP_I2C_REPORT_LEN);
 730                 return -EIO;
 731         }
 732
 733         return 0;
 734 }
 735
 736 const struct elan_transport_ops elan_i2c_ops = {
 737         .initialize             = elan_i2c_initialize,
 738         .sleep_control          = elan_i2c_sleep_control,
 739         .power_control          = elan_i2c_power_control,
 740         .set_mode               = elan_i2c_set_mode,
 741
 742         .calibrate              = elan_i2c_calibrate,
 743         .calibrate_result       = elan_i2c_calibrate_result,
 744
 745         .get_baseline_data      = elan_i2c_get_baseline_data,
 746
 747         .get_version            = elan_i2c_get_version,
 748         .get_sm_version         = elan_i2c_get_sm_version,
 749         .get_product_id         = elan_i2c_get_product_id,
 750         .get_checksum           = elan_i2c_get_checksum,
 751         .get_pressure_adjustment = elan_i2c_get_pressure_adjustment,
 752
 753         .get_max                = elan_i2c_get_max,
 754         .get_resolution         = elan_i2c_get_resolution,
 755         .get_num_traces         = elan_i2c_get_num_traces,
 756
 757         .iap_get_mode           = elan_i2c_iap_get_mode,
 758         .iap_reset              = elan_i2c_iap_reset,
 759
 760         .prepare_fw_update      = elan_i2c_prepare_fw_update,
 761         .write_fw_block         = elan_i2c_write_fw_block,
 762         .finish_fw_update       = elan_i2c_finish_fw_update,
 763
 764         .get_pattern            = elan_i2c_get_pattern,
 765
 766         .get_report             = elan_i2c_get_report,
 767 };