linux/drivers/input/touchscreen/silead.c
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   1/* -------------------------------------------------------------------------
   2 * Copyright (C) 2014-2015, Intel Corporation
   3 *
   4 * Derived from:
   5 *  gslX68X.c
   6 *  Copyright (C) 2010-2015, Shanghai Sileadinc Co.Ltd
   7 *
   8 *  This program is free software; you can redistribute it and/or modify
   9 *  it under the terms of the GNU General Public License as published by
  10 *  the Free Software Foundation; either version 2 of the License, or
  11 *  (at your option) any later version.
  12 *
  13 *  This program is distributed in the hope that it will be useful,
  14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 *  GNU General Public License for more details.
  17 * -------------------------------------------------------------------------
  18 */
  19
  20#include <linux/i2c.h>
  21#include <linux/module.h>
  22#include <linux/acpi.h>
  23#include <linux/interrupt.h>
  24#include <linux/gpio/consumer.h>
  25#include <linux/delay.h>
  26#include <linux/firmware.h>
  27#include <linux/input.h>
  28#include <linux/input/mt.h>
  29#include <linux/input/touchscreen.h>
  30#include <linux/pm.h>
  31#include <linux/irq.h>
  32#include <linux/regulator/consumer.h>
  33
  34#include <asm/unaligned.h>
  35
  36#define SILEAD_TS_NAME          "silead_ts"
  37
  38#define SILEAD_REG_RESET        0xE0
  39#define SILEAD_REG_DATA         0x80
  40#define SILEAD_REG_TOUCH_NR     0x80
  41#define SILEAD_REG_POWER        0xBC
  42#define SILEAD_REG_CLOCK        0xE4
  43#define SILEAD_REG_STATUS       0xB0
  44#define SILEAD_REG_ID           0xFC
  45#define SILEAD_REG_MEM_CHECK    0xB0
  46
  47#define SILEAD_STATUS_OK        0x5A5A5A5A
  48#define SILEAD_TS_DATA_LEN      44
  49#define SILEAD_CLOCK            0x04
  50
  51#define SILEAD_CMD_RESET        0x88
  52#define SILEAD_CMD_START        0x00
  53
  54#define SILEAD_POINT_DATA_LEN   0x04
  55#define SILEAD_POINT_Y_OFF      0x00
  56#define SILEAD_POINT_Y_MSB_OFF  0x01
  57#define SILEAD_POINT_X_OFF      0x02
  58#define SILEAD_POINT_X_MSB_OFF  0x03
  59#define SILEAD_EXTRA_DATA_MASK  0xF0
  60
  61#define SILEAD_CMD_SLEEP_MIN    10000
  62#define SILEAD_CMD_SLEEP_MAX    20000
  63#define SILEAD_POWER_SLEEP      20
  64#define SILEAD_STARTUP_SLEEP    30
  65
  66#define SILEAD_MAX_FINGERS      10
  67
  68enum silead_ts_power {
  69        SILEAD_POWER_ON  = 1,
  70        SILEAD_POWER_OFF = 0
  71};
  72
  73struct silead_ts_data {
  74        struct i2c_client *client;
  75        struct gpio_desc *gpio_power;
  76        struct input_dev *input;
  77        struct regulator_bulk_data regulators[2];
  78        char fw_name[64];
  79        struct touchscreen_properties prop;
  80        u32 max_fingers;
  81        u32 chip_id;
  82        struct input_mt_pos pos[SILEAD_MAX_FINGERS];
  83        int slots[SILEAD_MAX_FINGERS];
  84        int id[SILEAD_MAX_FINGERS];
  85};
  86
  87struct silead_fw_data {
  88        u32 offset;
  89        u32 val;
  90};
  91
  92static int silead_ts_request_input_dev(struct silead_ts_data *data)
  93{
  94        struct device *dev = &data->client->dev;
  95        int error;
  96
  97        data->input = devm_input_allocate_device(dev);
  98        if (!data->input) {
  99                dev_err(dev,
 100                        "Failed to allocate input device\n");
 101                return -ENOMEM;
 102        }
 103
 104        input_set_abs_params(data->input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
 105        input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
 106        touchscreen_parse_properties(data->input, true, &data->prop);
 107
 108        input_mt_init_slots(data->input, data->max_fingers,
 109                            INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |
 110                            INPUT_MT_TRACK);
 111
 112        if (device_property_read_bool(dev, "silead,home-button"))
 113                input_set_capability(data->input, EV_KEY, KEY_LEFTMETA);
 114
 115        data->input->name = SILEAD_TS_NAME;
 116        data->input->phys = "input/ts";
 117        data->input->id.bustype = BUS_I2C;
 118
 119        error = input_register_device(data->input);
 120        if (error) {
 121                dev_err(dev, "Failed to register input device: %d\n", error);
 122                return error;
 123        }
 124
 125        return 0;
 126}
 127
 128static void silead_ts_set_power(struct i2c_client *client,
 129                                enum silead_ts_power state)
 130{
 131        struct silead_ts_data *data = i2c_get_clientdata(client);
 132
 133        if (data->gpio_power) {
 134                gpiod_set_value_cansleep(data->gpio_power, state);
 135                msleep(SILEAD_POWER_SLEEP);
 136        }
 137}
 138
 139static void silead_ts_read_data(struct i2c_client *client)
 140{
 141        struct silead_ts_data *data = i2c_get_clientdata(client);
 142        struct input_dev *input = data->input;
 143        struct device *dev = &client->dev;
 144        u8 *bufp, buf[SILEAD_TS_DATA_LEN];
 145        int touch_nr, softbutton, error, i;
 146        bool softbutton_pressed = false;
 147
 148        error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,
 149                                              SILEAD_TS_DATA_LEN, buf);
 150        if (error < 0) {
 151                dev_err(dev, "Data read error %d\n", error);
 152                return;
 153        }
 154
 155        if (buf[0] > data->max_fingers) {
 156                dev_warn(dev, "More touches reported then supported %d > %d\n",
 157                         buf[0], data->max_fingers);
 158                buf[0] = data->max_fingers;
 159        }
 160
 161        touch_nr = 0;
 162        bufp = buf + SILEAD_POINT_DATA_LEN;
 163        for (i = 0; i < buf[0]; i++, bufp += SILEAD_POINT_DATA_LEN) {
 164                softbutton = (bufp[SILEAD_POINT_Y_MSB_OFF] &
 165                              SILEAD_EXTRA_DATA_MASK) >> 4;
 166
 167                if (softbutton) {
 168                        /*
 169                         * For now only respond to softbutton == 0x01, some
 170                         * tablets *without* a capacative button send 0x04
 171                         * when crossing the edges of the screen.
 172                         */
 173                        if (softbutton == 0x01)
 174                                softbutton_pressed = true;
 175
 176                        continue;
 177                }
 178
 179                /*
 180                 * Bits 4-7 are the touch id, note not all models have
 181                 * hardware touch ids so atm we don't use these.
 182                 */
 183                data->id[touch_nr] = (bufp[SILEAD_POINT_X_MSB_OFF] &
 184                                      SILEAD_EXTRA_DATA_MASK) >> 4;
 185                touchscreen_set_mt_pos(&data->pos[touch_nr], &data->prop,
 186                        get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,
 187                        get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);
 188                touch_nr++;
 189        }
 190
 191        input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
 192
 193        for (i = 0; i < touch_nr; i++) {
 194                input_mt_slot(input, data->slots[i]);
 195                input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
 196                input_report_abs(input, ABS_MT_POSITION_X, data->pos[i].x);
 197                input_report_abs(input, ABS_MT_POSITION_Y, data->pos[i].y);
 198
 199                dev_dbg(dev, "x=%d y=%d hw_id=%d sw_id=%d\n", data->pos[i].x,
 200                        data->pos[i].y, data->id[i], data->slots[i]);
 201        }
 202
 203        input_mt_sync_frame(input);
 204        input_report_key(input, KEY_LEFTMETA, softbutton_pressed);
 205        input_sync(input);
 206}
 207
 208static int silead_ts_init(struct i2c_client *client)
 209{
 210        struct silead_ts_data *data = i2c_get_clientdata(client);
 211        int error;
 212
 213        error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
 214                                          SILEAD_CMD_RESET);
 215        if (error)
 216                goto i2c_write_err;
 217        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 218
 219        error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
 220                                        data->max_fingers);
 221        if (error)
 222                goto i2c_write_err;
 223        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 224
 225        error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
 226                                          SILEAD_CLOCK);
 227        if (error)
 228                goto i2c_write_err;
 229        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 230
 231        error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
 232                                          SILEAD_CMD_START);
 233        if (error)
 234                goto i2c_write_err;
 235        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 236
 237        return 0;
 238
 239i2c_write_err:
 240        dev_err(&client->dev, "Registers clear error %d\n", error);
 241        return error;
 242}
 243
 244static int silead_ts_reset(struct i2c_client *client)
 245{
 246        int error;
 247
 248        error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
 249                                          SILEAD_CMD_RESET);
 250        if (error)
 251                goto i2c_write_err;
 252        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 253
 254        error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
 255                                          SILEAD_CLOCK);
 256        if (error)
 257                goto i2c_write_err;
 258        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 259
 260        error = i2c_smbus_write_byte_data(client, SILEAD_REG_POWER,
 261                                          SILEAD_CMD_START);
 262        if (error)
 263                goto i2c_write_err;
 264        usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 265
 266        return 0;
 267
 268i2c_write_err:
 269        dev_err(&client->dev, "Chip reset error %d\n", error);
 270        return error;
 271}
 272
 273static int silead_ts_startup(struct i2c_client *client)
 274{
 275        int error;
 276
 277        error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET, 0x00);
 278        if (error) {
 279                dev_err(&client->dev, "Startup error %d\n", error);
 280                return error;
 281        }
 282
 283        msleep(SILEAD_STARTUP_SLEEP);
 284
 285        return 0;
 286}
 287
 288static int silead_ts_load_fw(struct i2c_client *client)
 289{
 290        struct device *dev = &client->dev;
 291        struct silead_ts_data *data = i2c_get_clientdata(client);
 292        unsigned int fw_size, i;
 293        const struct firmware *fw;
 294        struct silead_fw_data *fw_data;
 295        int error;
 296
 297        dev_dbg(dev, "Firmware file name: %s", data->fw_name);
 298
 299        error = request_firmware(&fw, data->fw_name, dev);
 300        if (error) {
 301                dev_err(dev, "Firmware request error %d\n", error);
 302                return error;
 303        }
 304
 305        fw_size = fw->size / sizeof(*fw_data);
 306        fw_data = (struct silead_fw_data *)fw->data;
 307
 308        for (i = 0; i < fw_size; i++) {
 309                error = i2c_smbus_write_i2c_block_data(client,
 310                                                       fw_data[i].offset,
 311                                                       4,
 312                                                       (u8 *)&fw_data[i].val);
 313                if (error) {
 314                        dev_err(dev, "Firmware load error %d\n", error);
 315                        break;
 316                }
 317        }
 318
 319        release_firmware(fw);
 320        return error ?: 0;
 321}
 322
 323static u32 silead_ts_get_status(struct i2c_client *client)
 324{
 325        int error;
 326        __le32 status;
 327
 328        error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS,
 329                                              sizeof(status), (u8 *)&status);
 330        if (error < 0) {
 331                dev_err(&client->dev, "Status read error %d\n", error);
 332                return error;
 333        }
 334
 335        return le32_to_cpu(status);
 336}
 337
 338static int silead_ts_get_id(struct i2c_client *client)
 339{
 340        struct silead_ts_data *data = i2c_get_clientdata(client);
 341        __le32 chip_id;
 342        int error;
 343
 344        error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID,
 345                                              sizeof(chip_id), (u8 *)&chip_id);
 346        if (error < 0) {
 347                dev_err(&client->dev, "Chip ID read error %d\n", error);
 348                return error;
 349        }
 350
 351        data->chip_id = le32_to_cpu(chip_id);
 352        dev_info(&client->dev, "Silead chip ID: 0x%8X", data->chip_id);
 353
 354        return 0;
 355}
 356
 357static int silead_ts_setup(struct i2c_client *client)
 358{
 359        int error;
 360        u32 status;
 361
 362        silead_ts_set_power(client, SILEAD_POWER_OFF);
 363        silead_ts_set_power(client, SILEAD_POWER_ON);
 364
 365        error = silead_ts_get_id(client);
 366        if (error)
 367                return error;
 368
 369        error = silead_ts_init(client);
 370        if (error)
 371                return error;
 372
 373        error = silead_ts_reset(client);
 374        if (error)
 375                return error;
 376
 377        error = silead_ts_load_fw(client);
 378        if (error)
 379                return error;
 380
 381        error = silead_ts_startup(client);
 382        if (error)
 383                return error;
 384
 385        status = silead_ts_get_status(client);
 386        if (status != SILEAD_STATUS_OK) {
 387                dev_err(&client->dev,
 388                        "Initialization error, status: 0x%X\n", status);
 389                return -ENODEV;
 390        }
 391
 392        return 0;
 393}
 394
 395static irqreturn_t silead_ts_threaded_irq_handler(int irq, void *id)
 396{
 397        struct silead_ts_data *data = id;
 398        struct i2c_client *client = data->client;
 399
 400        silead_ts_read_data(client);
 401
 402        return IRQ_HANDLED;
 403}
 404
 405static void silead_ts_read_props(struct i2c_client *client)
 406{
 407        struct silead_ts_data *data = i2c_get_clientdata(client);
 408        struct device *dev = &client->dev;
 409        const char *str;
 410        int error;
 411
 412        error = device_property_read_u32(dev, "silead,max-fingers",
 413                                         &data->max_fingers);
 414        if (error) {
 415                dev_dbg(dev, "Max fingers read error %d\n", error);
 416                data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
 417        }
 418
 419        error = device_property_read_string(dev, "firmware-name", &str);
 420        if (!error)
 421                snprintf(data->fw_name, sizeof(data->fw_name),
 422                         "silead/%s", str);
 423        else
 424                dev_dbg(dev, "Firmware file name read error. Using default.");
 425}
 426
 427#ifdef CONFIG_ACPI
 428static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
 429                                         const struct i2c_device_id *id)
 430{
 431        const struct acpi_device_id *acpi_id;
 432        struct device *dev = &data->client->dev;
 433        int i;
 434
 435        if (ACPI_HANDLE(dev)) {
 436                acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
 437                if (!acpi_id)
 438                        return -ENODEV;
 439
 440                snprintf(data->fw_name, sizeof(data->fw_name),
 441                         "silead/%s.fw", acpi_id->id);
 442
 443                for (i = 0; i < strlen(data->fw_name); i++)
 444                        data->fw_name[i] = tolower(data->fw_name[i]);
 445        } else {
 446                snprintf(data->fw_name, sizeof(data->fw_name),
 447                         "silead/%s.fw", id->name);
 448        }
 449
 450        return 0;
 451}
 452#else
 453static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
 454                                         const struct i2c_device_id *id)
 455{
 456        snprintf(data->fw_name, sizeof(data->fw_name),
 457                 "silead/%s.fw", id->name);
 458        return 0;
 459}
 460#endif
 461
 462static void silead_disable_regulator(void *arg)
 463{
 464        struct silead_ts_data *data = arg;
 465
 466        regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
 467}
 468
 469static int silead_ts_probe(struct i2c_client *client,
 470                           const struct i2c_device_id *id)
 471{
 472        struct silead_ts_data *data;
 473        struct device *dev = &client->dev;
 474        int error;
 475
 476        if (!i2c_check_functionality(client->adapter,
 477                                     I2C_FUNC_I2C |
 478                                     I2C_FUNC_SMBUS_READ_I2C_BLOCK |
 479                                     I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
 480                dev_err(dev, "I2C functionality check failed\n");
 481                return -ENXIO;
 482        }
 483
 484        data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 485        if (!data)
 486                return -ENOMEM;
 487
 488        i2c_set_clientdata(client, data);
 489        data->client = client;
 490
 491        error = silead_ts_set_default_fw_name(data, id);
 492        if (error)
 493                return error;
 494
 495        silead_ts_read_props(client);
 496
 497        /* We must have the IRQ provided by DT or ACPI subsytem */
 498        if (client->irq <= 0)
 499                return -ENODEV;
 500
 501        data->regulators[0].supply = "vddio";
 502        data->regulators[1].supply = "avdd";
 503        error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
 504                                        data->regulators);
 505        if (error)
 506                return error;
 507
 508        /*
 509         * Enable regulators at probe and disable them at remove, we need
 510         * to keep the chip powered otherwise it forgets its firmware.
 511         */
 512        error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
 513                                      data->regulators);
 514        if (error)
 515                return error;
 516
 517        error = devm_add_action_or_reset(dev, silead_disable_regulator, data);
 518        if (error)
 519                return error;
 520
 521        /* Power GPIO pin */
 522        data->gpio_power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
 523        if (IS_ERR(data->gpio_power)) {
 524                if (PTR_ERR(data->gpio_power) != -EPROBE_DEFER)
 525                        dev_err(dev, "Shutdown GPIO request failed\n");
 526                return PTR_ERR(data->gpio_power);
 527        }
 528
 529        error = silead_ts_setup(client);
 530        if (error)
 531                return error;
 532
 533        error = silead_ts_request_input_dev(data);
 534        if (error)
 535                return error;
 536
 537        error = devm_request_threaded_irq(dev, client->irq,
 538                                          NULL, silead_ts_threaded_irq_handler,
 539                                          IRQF_ONESHOT, client->name, data);
 540        if (error) {
 541                if (error != -EPROBE_DEFER)
 542                        dev_err(dev, "IRQ request failed %d\n", error);
 543                return error;
 544        }
 545
 546        return 0;
 547}
 548
 549static int __maybe_unused silead_ts_suspend(struct device *dev)
 550{
 551        struct i2c_client *client = to_i2c_client(dev);
 552
 553        disable_irq(client->irq);
 554        silead_ts_set_power(client, SILEAD_POWER_OFF);
 555        return 0;
 556}
 557
 558static int __maybe_unused silead_ts_resume(struct device *dev)
 559{
 560        struct i2c_client *client = to_i2c_client(dev);
 561        int error, status;
 562
 563        silead_ts_set_power(client, SILEAD_POWER_ON);
 564
 565        error = silead_ts_reset(client);
 566        if (error)
 567                return error;
 568
 569        error = silead_ts_startup(client);
 570        if (error)
 571                return error;
 572
 573        status = silead_ts_get_status(client);
 574        if (status != SILEAD_STATUS_OK) {
 575                dev_err(dev, "Resume error, status: 0x%02x\n", status);
 576                return -ENODEV;
 577        }
 578
 579        enable_irq(client->irq);
 580
 581        return 0;
 582}
 583
 584static SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
 585
 586static const struct i2c_device_id silead_ts_id[] = {
 587        { "gsl1680", 0 },
 588        { "gsl1688", 0 },
 589        { "gsl3670", 0 },
 590        { "gsl3675", 0 },
 591        { "gsl3692", 0 },
 592        { "mssl1680", 0 },
 593        { }
 594};
 595MODULE_DEVICE_TABLE(i2c, silead_ts_id);
 596
 597#ifdef CONFIG_ACPI
 598static const struct acpi_device_id silead_ts_acpi_match[] = {
 599        { "GSL1680", 0 },
 600        { "GSL1688", 0 },
 601        { "GSL3670", 0 },
 602        { "GSL3675", 0 },
 603        { "GSL3692", 0 },
 604        { "MSSL1680", 0 },
 605        { "MSSL0001", 0 },
 606        { "MSSL0002", 0 },
 607        { }
 608};
 609MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
 610#endif
 611
 612#ifdef CONFIG_OF
 613static const struct of_device_id silead_ts_of_match[] = {
 614        { .compatible = "silead,gsl1680" },
 615        { .compatible = "silead,gsl1688" },
 616        { .compatible = "silead,gsl3670" },
 617        { .compatible = "silead,gsl3675" },
 618        { .compatible = "silead,gsl3692" },
 619        { },
 620};
 621MODULE_DEVICE_TABLE(of, silead_ts_of_match);
 622#endif
 623
 624static struct i2c_driver silead_ts_driver = {
 625        .probe = silead_ts_probe,
 626        .id_table = silead_ts_id,
 627        .driver = {
 628                .name = SILEAD_TS_NAME,
 629                .acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
 630                .of_match_table = of_match_ptr(silead_ts_of_match),
 631                .pm = &silead_ts_pm,
 632        },
 633};
 634module_i2c_driver(silead_ts_driver);
 635
 636MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
 637MODULE_DESCRIPTION("Silead I2C touchscreen driver");
 638MODULE_LICENSE("GPL");
 639