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