linux/drivers/input/touchscreen/zforce_ts.c
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   1/*
   2 * Copyright (C) 2012-2013 MundoReader S.L.
   3 * Author: Heiko Stuebner <heiko@sntech.de>
   4 *
   5 * based in parts on Nook zforce driver
   6 *
   7 * Copyright (C) 2010 Barnes & Noble, Inc.
   8 * Author: Pieter Truter<ptruter@intrinsyc.com>
   9 *
  10 * This software is licensed under the terms of the GNU General Public
  11 * License version 2, as published by the Free Software Foundation, and
  12 * may be copied, distributed, and modified under those terms.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 */
  19
  20#include <linux/module.h>
  21#include <linux/hrtimer.h>
  22#include <linux/slab.h>
  23#include <linux/input.h>
  24#include <linux/interrupt.h>
  25#include <linux/i2c.h>
  26#include <linux/delay.h>
  27#include <linux/gpio.h>
  28#include <linux/device.h>
  29#include <linux/sysfs.h>
  30#include <linux/input/mt.h>
  31#include <linux/platform_data/zforce_ts.h>
  32#include <linux/regulator/consumer.h>
  33#include <linux/delay.h>
  34#include <linux/of.h>
  35#include <linux/of_gpio.h>
  36
  37#define WAIT_TIMEOUT            msecs_to_jiffies(1000)
  38
  39#define FRAME_START             0xee
  40#define FRAME_MAXSIZE           257
  41
  42/* Offsets of the different parts of the payload the controller sends */
  43#define PAYLOAD_HEADER          0
  44#define PAYLOAD_LENGTH          1
  45#define PAYLOAD_BODY            2
  46
  47/* Response offsets */
  48#define RESPONSE_ID             0
  49#define RESPONSE_DATA           1
  50
  51/* Commands */
  52#define COMMAND_DEACTIVATE      0x00
  53#define COMMAND_INITIALIZE      0x01
  54#define COMMAND_RESOLUTION      0x02
  55#define COMMAND_SETCONFIG       0x03
  56#define COMMAND_DATAREQUEST     0x04
  57#define COMMAND_SCANFREQ        0x08
  58#define COMMAND_STATUS          0X1e
  59
  60/*
  61 * Responses the controller sends as a result of
  62 * command requests
  63 */
  64#define RESPONSE_DEACTIVATE     0x00
  65#define RESPONSE_INITIALIZE     0x01
  66#define RESPONSE_RESOLUTION     0x02
  67#define RESPONSE_SETCONFIG      0x03
  68#define RESPONSE_SCANFREQ       0x08
  69#define RESPONSE_STATUS         0X1e
  70
  71/*
  72 * Notifications are sent by the touch controller without
  73 * being requested by the driver and include for example
  74 * touch indications
  75 */
  76#define NOTIFICATION_TOUCH              0x04
  77#define NOTIFICATION_BOOTCOMPLETE       0x07
  78#define NOTIFICATION_OVERRUN            0x25
  79#define NOTIFICATION_PROXIMITY          0x26
  80#define NOTIFICATION_INVALID_COMMAND    0xfe
  81
  82#define ZFORCE_REPORT_POINTS            2
  83#define ZFORCE_MAX_AREA                 0xff
  84
  85#define STATE_DOWN                      0
  86#define STATE_MOVE                      1
  87#define STATE_UP                        2
  88
  89#define SETCONFIG_DUALTOUCH             (1 << 0)
  90
  91struct zforce_point {
  92        int coord_x;
  93        int coord_y;
  94        int state;
  95        int id;
  96        int area_major;
  97        int area_minor;
  98        int orientation;
  99        int pressure;
 100        int prblty;
 101};
 102
 103/*
 104 * @client              the i2c_client
 105 * @input               the input device
 106 * @suspending          in the process of going to suspend (don't emit wakeup
 107 *                      events for commands executed to suspend the device)
 108 * @suspended           device suspended
 109 * @access_mutex        serialize i2c-access, to keep multipart reads together
 110 * @command_done        completion to wait for the command result
 111 * @command_mutex       serialize commands sent to the ic
 112 * @command_waiting     the id of the command that is currently waiting
 113 *                      for a result
 114 * @command_result      returned result of the command
 115 */
 116struct zforce_ts {
 117        struct i2c_client       *client;
 118        struct input_dev        *input;
 119        const struct zforce_ts_platdata *pdata;
 120        char                    phys[32];
 121
 122        struct regulator        *reg_vdd;
 123
 124        bool                    suspending;
 125        bool                    suspended;
 126        bool                    boot_complete;
 127
 128        /* Firmware version information */
 129        u16                     version_major;
 130        u16                     version_minor;
 131        u16                     version_build;
 132        u16                     version_rev;
 133
 134        struct mutex            access_mutex;
 135
 136        struct completion       command_done;
 137        struct mutex            command_mutex;
 138        int                     command_waiting;
 139        int                     command_result;
 140};
 141
 142static int zforce_command(struct zforce_ts *ts, u8 cmd)
 143{
 144        struct i2c_client *client = ts->client;
 145        char buf[3];
 146        int ret;
 147
 148        dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
 149
 150        buf[0] = FRAME_START;
 151        buf[1] = 1; /* data size, command only */
 152        buf[2] = cmd;
 153
 154        mutex_lock(&ts->access_mutex);
 155        ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
 156        mutex_unlock(&ts->access_mutex);
 157        if (ret < 0) {
 158                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 159                return ret;
 160        }
 161
 162        return 0;
 163}
 164
 165static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
 166{
 167        struct i2c_client *client = ts->client;
 168        int ret;
 169
 170        ret = mutex_trylock(&ts->command_mutex);
 171        if (!ret) {
 172                dev_err(&client->dev, "already waiting for a command\n");
 173                return -EBUSY;
 174        }
 175
 176        dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
 177                buf[1], buf[2]);
 178
 179        ts->command_waiting = buf[2];
 180
 181        mutex_lock(&ts->access_mutex);
 182        ret = i2c_master_send(client, buf, len);
 183        mutex_unlock(&ts->access_mutex);
 184        if (ret < 0) {
 185                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 186                goto unlock;
 187        }
 188
 189        dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
 190
 191        if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
 192                ret = -ETIME;
 193                goto unlock;
 194        }
 195
 196        ret = ts->command_result;
 197
 198unlock:
 199        mutex_unlock(&ts->command_mutex);
 200        return ret;
 201}
 202
 203static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
 204{
 205        struct i2c_client *client = ts->client;
 206        char buf[3];
 207        int ret;
 208
 209        dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
 210
 211        buf[0] = FRAME_START;
 212        buf[1] = 1; /* data size, command only */
 213        buf[2] = cmd;
 214
 215        ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 216        if (ret < 0) {
 217                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 218                return ret;
 219        }
 220
 221        return 0;
 222}
 223
 224static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
 225{
 226        struct i2c_client *client = ts->client;
 227        char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
 228                        (x & 0xff), ((x >> 8) & 0xff),
 229                        (y & 0xff), ((y >> 8) & 0xff) };
 230
 231        dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
 232
 233        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 234}
 235
 236static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
 237                                 u16 stylus)
 238{
 239        struct i2c_client *client = ts->client;
 240        char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
 241                        (idle & 0xff), ((idle >> 8) & 0xff),
 242                        (finger & 0xff), ((finger >> 8) & 0xff),
 243                        (stylus & 0xff), ((stylus >> 8) & 0xff) };
 244
 245        dev_dbg(&client->dev,
 246                "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
 247                idle, finger, stylus);
 248
 249        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 250}
 251
 252static int zforce_setconfig(struct zforce_ts *ts, char b1)
 253{
 254        struct i2c_client *client = ts->client;
 255        char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
 256                        b1, 0, 0, 0 };
 257
 258        dev_dbg(&client->dev, "set config to (%d)\n", b1);
 259
 260        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 261}
 262
 263static int zforce_start(struct zforce_ts *ts)
 264{
 265        struct i2c_client *client = ts->client;
 266        const struct zforce_ts_platdata *pdata = ts->pdata;
 267        int ret;
 268
 269        dev_dbg(&client->dev, "starting device\n");
 270
 271        ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
 272        if (ret) {
 273                dev_err(&client->dev, "Unable to initialize, %d\n", ret);
 274                return ret;
 275        }
 276
 277        ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
 278        if (ret) {
 279                dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
 280                goto error;
 281        }
 282
 283        ret = zforce_scan_frequency(ts, 10, 50, 50);
 284        if (ret) {
 285                dev_err(&client->dev, "Unable to set scan frequency, %d\n",
 286                        ret);
 287                goto error;
 288        }
 289
 290        ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
 291        if (ret) {
 292                dev_err(&client->dev, "Unable to set config\n");
 293                goto error;
 294        }
 295
 296        /* start sending touch events */
 297        ret = zforce_command(ts, COMMAND_DATAREQUEST);
 298        if (ret) {
 299                dev_err(&client->dev, "Unable to request data\n");
 300                goto error;
 301        }
 302
 303        /*
 304         * Per NN, initial cal. take max. of 200msec.
 305         * Allow time to complete this calibration
 306         */
 307        msleep(200);
 308
 309        return 0;
 310
 311error:
 312        zforce_command_wait(ts, COMMAND_DEACTIVATE);
 313        return ret;
 314}
 315
 316static int zforce_stop(struct zforce_ts *ts)
 317{
 318        struct i2c_client *client = ts->client;
 319        int ret;
 320
 321        dev_dbg(&client->dev, "stopping device\n");
 322
 323        /* Deactivates touch sensing and puts the device into sleep. */
 324        ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
 325        if (ret != 0) {
 326                dev_err(&client->dev, "could not deactivate device, %d\n",
 327                        ret);
 328                return ret;
 329        }
 330
 331        return 0;
 332}
 333
 334static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
 335{
 336        struct i2c_client *client = ts->client;
 337        const struct zforce_ts_platdata *pdata = ts->pdata;
 338        struct zforce_point point;
 339        int count, i, num = 0;
 340
 341        count = payload[0];
 342        if (count > ZFORCE_REPORT_POINTS) {
 343                dev_warn(&client->dev,
 344                         "too many coordinates %d, expected max %d\n",
 345                         count, ZFORCE_REPORT_POINTS);
 346                count = ZFORCE_REPORT_POINTS;
 347        }
 348
 349        for (i = 0; i < count; i++) {
 350                point.coord_x =
 351                        payload[9 * i + 2] << 8 | payload[9 * i + 1];
 352                point.coord_y =
 353                        payload[9 * i + 4] << 8 | payload[9 * i + 3];
 354
 355                if (point.coord_x > pdata->x_max ||
 356                    point.coord_y > pdata->y_max) {
 357                        dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
 358                                point.coord_x, point.coord_y);
 359                        point.coord_x = point.coord_y = 0;
 360                }
 361
 362                point.state = payload[9 * i + 5] & 0x03;
 363                point.id = (payload[9 * i + 5] & 0xfc) >> 2;
 364
 365                /* determine touch major, minor and orientation */
 366                point.area_major = max(payload[9 * i + 6],
 367                                          payload[9 * i + 7]);
 368                point.area_minor = min(payload[9 * i + 6],
 369                                          payload[9 * i + 7]);
 370                point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
 371
 372                point.pressure = payload[9 * i + 8];
 373                point.prblty = payload[9 * i + 9];
 374
 375                dev_dbg(&client->dev,
 376                        "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
 377                        i, count, point.state, point.id,
 378                        point.pressure, point.prblty,
 379                        point.coord_x, point.coord_y,
 380                        point.area_major, point.area_minor,
 381                        point.orientation);
 382
 383                /* the zforce id starts with "1", so needs to be decreased */
 384                input_mt_slot(ts->input, point.id - 1);
 385
 386                input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
 387                                                point.state != STATE_UP);
 388
 389                if (point.state != STATE_UP) {
 390                        input_report_abs(ts->input, ABS_MT_POSITION_X,
 391                                         point.coord_x);
 392                        input_report_abs(ts->input, ABS_MT_POSITION_Y,
 393                                         point.coord_y);
 394                        input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
 395                                         point.area_major);
 396                        input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
 397                                         point.area_minor);
 398                        input_report_abs(ts->input, ABS_MT_ORIENTATION,
 399                                         point.orientation);
 400                        num++;
 401                }
 402        }
 403
 404        input_mt_sync_frame(ts->input);
 405
 406        input_mt_report_finger_count(ts->input, num);
 407
 408        input_sync(ts->input);
 409
 410        return 0;
 411}
 412
 413static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
 414{
 415        struct i2c_client *client = ts->client;
 416        int ret;
 417
 418        mutex_lock(&ts->access_mutex);
 419
 420        /* read 2 byte message header */
 421        ret = i2c_master_recv(client, buf, 2);
 422        if (ret < 0) {
 423                dev_err(&client->dev, "error reading header: %d\n", ret);
 424                goto unlock;
 425        }
 426
 427        if (buf[PAYLOAD_HEADER] != FRAME_START) {
 428                dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
 429                ret = -EIO;
 430                goto unlock;
 431        }
 432
 433        if (buf[PAYLOAD_LENGTH] == 0) {
 434                dev_err(&client->dev, "invalid payload length: %d\n",
 435                        buf[PAYLOAD_LENGTH]);
 436                ret = -EIO;
 437                goto unlock;
 438        }
 439
 440        /* read the message */
 441        ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
 442        if (ret < 0) {
 443                dev_err(&client->dev, "error reading payload: %d\n", ret);
 444                goto unlock;
 445        }
 446
 447        dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
 448                buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
 449
 450unlock:
 451        mutex_unlock(&ts->access_mutex);
 452        return ret;
 453}
 454
 455static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
 456{
 457        struct i2c_client *client = ts->client;
 458
 459        if (ts->command_waiting == cmd) {
 460                dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
 461                ts->command_result = result;
 462                complete(&ts->command_done);
 463        } else {
 464                dev_dbg(&client->dev, "command %d not for us\n", cmd);
 465        }
 466}
 467
 468static irqreturn_t zforce_irq(int irq, void *dev_id)
 469{
 470        struct zforce_ts *ts = dev_id;
 471        struct i2c_client *client = ts->client;
 472
 473        if (ts->suspended && device_may_wakeup(&client->dev))
 474                pm_wakeup_event(&client->dev, 500);
 475
 476        return IRQ_WAKE_THREAD;
 477}
 478
 479static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
 480{
 481        struct zforce_ts *ts = dev_id;
 482        struct i2c_client *client = ts->client;
 483        const struct zforce_ts_platdata *pdata = ts->pdata;
 484        int ret;
 485        u8 payload_buffer[FRAME_MAXSIZE];
 486        u8 *payload;
 487
 488        /*
 489         * When still suspended, return.
 490         * Due to the level-interrupt we will get re-triggered later.
 491         */
 492        if (ts->suspended) {
 493                msleep(20);
 494                return IRQ_HANDLED;
 495        }
 496
 497        dev_dbg(&client->dev, "handling interrupt\n");
 498
 499        /* Don't emit wakeup events from commands run by zforce_suspend */
 500        if (!ts->suspending && device_may_wakeup(&client->dev))
 501                pm_stay_awake(&client->dev);
 502
 503        while (!gpio_get_value(pdata->gpio_int)) {
 504                ret = zforce_read_packet(ts, payload_buffer);
 505                if (ret < 0) {
 506                        dev_err(&client->dev,
 507                                "could not read packet, ret: %d\n", ret);
 508                        break;
 509                }
 510
 511                payload =  &payload_buffer[PAYLOAD_BODY];
 512
 513                switch (payload[RESPONSE_ID]) {
 514                case NOTIFICATION_TOUCH:
 515                        /*
 516                         * Always report touch-events received while
 517                         * suspending, when being a wakeup source
 518                         */
 519                        if (ts->suspending && device_may_wakeup(&client->dev))
 520                                pm_wakeup_event(&client->dev, 500);
 521                        zforce_touch_event(ts, &payload[RESPONSE_DATA]);
 522                        break;
 523
 524                case NOTIFICATION_BOOTCOMPLETE:
 525                        ts->boot_complete = payload[RESPONSE_DATA];
 526                        zforce_complete(ts, payload[RESPONSE_ID], 0);
 527                        break;
 528
 529                case RESPONSE_INITIALIZE:
 530                case RESPONSE_DEACTIVATE:
 531                case RESPONSE_SETCONFIG:
 532                case RESPONSE_RESOLUTION:
 533                case RESPONSE_SCANFREQ:
 534                        zforce_complete(ts, payload[RESPONSE_ID],
 535                                        payload[RESPONSE_DATA]);
 536                        break;
 537
 538                case RESPONSE_STATUS:
 539                        /*
 540                         * Version Payload Results
 541                         * [2:major] [2:minor] [2:build] [2:rev]
 542                         */
 543                        ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
 544                                                payload[RESPONSE_DATA];
 545                        ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
 546                                                payload[RESPONSE_DATA + 2];
 547                        ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
 548                                                payload[RESPONSE_DATA + 4];
 549                        ts->version_rev   = (payload[RESPONSE_DATA + 7] << 8) |
 550                                                payload[RESPONSE_DATA + 6];
 551                        dev_dbg(&ts->client->dev,
 552                                "Firmware Version %04x:%04x %04x:%04x\n",
 553                                ts->version_major, ts->version_minor,
 554                                ts->version_build, ts->version_rev);
 555
 556                        zforce_complete(ts, payload[RESPONSE_ID], 0);
 557                        break;
 558
 559                case NOTIFICATION_INVALID_COMMAND:
 560                        dev_err(&ts->client->dev, "invalid command: 0x%x\n",
 561                                payload[RESPONSE_DATA]);
 562                        break;
 563
 564                default:
 565                        dev_err(&ts->client->dev,
 566                                "unrecognized response id: 0x%x\n",
 567                                payload[RESPONSE_ID]);
 568                        break;
 569                }
 570        }
 571
 572        if (!ts->suspending && device_may_wakeup(&client->dev))
 573                pm_relax(&client->dev);
 574
 575        dev_dbg(&client->dev, "finished interrupt\n");
 576
 577        return IRQ_HANDLED;
 578}
 579
 580static int zforce_input_open(struct input_dev *dev)
 581{
 582        struct zforce_ts *ts = input_get_drvdata(dev);
 583        int ret;
 584
 585        ret = zforce_start(ts);
 586        if (ret)
 587                return ret;
 588
 589        return 0;
 590}
 591
 592static void zforce_input_close(struct input_dev *dev)
 593{
 594        struct zforce_ts *ts = input_get_drvdata(dev);
 595        struct i2c_client *client = ts->client;
 596        int ret;
 597
 598        ret = zforce_stop(ts);
 599        if (ret)
 600                dev_warn(&client->dev, "stopping zforce failed\n");
 601
 602        return;
 603}
 604
 605static int __maybe_unused zforce_suspend(struct device *dev)
 606{
 607        struct i2c_client *client = to_i2c_client(dev);
 608        struct zforce_ts *ts = i2c_get_clientdata(client);
 609        struct input_dev *input = ts->input;
 610        int ret = 0;
 611
 612        mutex_lock(&input->mutex);
 613        ts->suspending = true;
 614
 615        /*
 616         * When configured as a wakeup source device should always wake
 617         * the system, therefore start device if necessary.
 618         */
 619        if (device_may_wakeup(&client->dev)) {
 620                dev_dbg(&client->dev, "suspend while being a wakeup source\n");
 621
 622                /* Need to start device, if not open, to be a wakeup source. */
 623                if (!input->users) {
 624                        ret = zforce_start(ts);
 625                        if (ret)
 626                                goto unlock;
 627                }
 628
 629                enable_irq_wake(client->irq);
 630        } else if (input->users) {
 631                dev_dbg(&client->dev,
 632                        "suspend without being a wakeup source\n");
 633
 634                ret = zforce_stop(ts);
 635                if (ret)
 636                        goto unlock;
 637
 638                disable_irq(client->irq);
 639        }
 640
 641        ts->suspended = true;
 642
 643unlock:
 644        ts->suspending = false;
 645        mutex_unlock(&input->mutex);
 646
 647        return ret;
 648}
 649
 650static int __maybe_unused zforce_resume(struct device *dev)
 651{
 652        struct i2c_client *client = to_i2c_client(dev);
 653        struct zforce_ts *ts = i2c_get_clientdata(client);
 654        struct input_dev *input = ts->input;
 655        int ret = 0;
 656
 657        mutex_lock(&input->mutex);
 658
 659        ts->suspended = false;
 660
 661        if (device_may_wakeup(&client->dev)) {
 662                dev_dbg(&client->dev, "resume from being a wakeup source\n");
 663
 664                disable_irq_wake(client->irq);
 665
 666                /* need to stop device if it was not open on suspend */
 667                if (!input->users) {
 668                        ret = zforce_stop(ts);
 669                        if (ret)
 670                                goto unlock;
 671                }
 672        } else if (input->users) {
 673                dev_dbg(&client->dev, "resume without being a wakeup source\n");
 674
 675                enable_irq(client->irq);
 676
 677                ret = zforce_start(ts);
 678                if (ret < 0)
 679                        goto unlock;
 680        }
 681
 682unlock:
 683        mutex_unlock(&input->mutex);
 684
 685        return ret;
 686}
 687
 688static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
 689
 690static void zforce_reset(void *data)
 691{
 692        struct zforce_ts *ts = data;
 693
 694        gpio_set_value(ts->pdata->gpio_rst, 0);
 695
 696        udelay(10);
 697
 698        if (!IS_ERR(ts->reg_vdd))
 699                regulator_disable(ts->reg_vdd);
 700}
 701
 702static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
 703{
 704        struct zforce_ts_platdata *pdata;
 705        struct device_node *np = dev->of_node;
 706
 707        if (!np)
 708                return ERR_PTR(-ENOENT);
 709
 710        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 711        if (!pdata) {
 712                dev_err(dev, "failed to allocate platform data\n");
 713                return ERR_PTR(-ENOMEM);
 714        }
 715
 716        pdata->gpio_int = of_get_gpio(np, 0);
 717        if (!gpio_is_valid(pdata->gpio_int)) {
 718                dev_err(dev, "failed to get interrupt gpio\n");
 719                return ERR_PTR(-EINVAL);
 720        }
 721
 722        pdata->gpio_rst = of_get_gpio(np, 1);
 723        if (!gpio_is_valid(pdata->gpio_rst)) {
 724                dev_err(dev, "failed to get reset gpio\n");
 725                return ERR_PTR(-EINVAL);
 726        }
 727
 728        if (of_property_read_u32(np, "x-size", &pdata->x_max)) {
 729                dev_err(dev, "failed to get x-size property\n");
 730                return ERR_PTR(-EINVAL);
 731        }
 732
 733        if (of_property_read_u32(np, "y-size", &pdata->y_max)) {
 734                dev_err(dev, "failed to get y-size property\n");
 735                return ERR_PTR(-EINVAL);
 736        }
 737
 738        return pdata;
 739}
 740
 741static int zforce_probe(struct i2c_client *client,
 742                        const struct i2c_device_id *id)
 743{
 744        const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
 745        struct zforce_ts *ts;
 746        struct input_dev *input_dev;
 747        int ret;
 748
 749        if (!pdata) {
 750                pdata = zforce_parse_dt(&client->dev);
 751                if (IS_ERR(pdata))
 752                        return PTR_ERR(pdata);
 753        }
 754
 755        ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
 756        if (!ts)
 757                return -ENOMEM;
 758
 759        ret = devm_gpio_request_one(&client->dev, pdata->gpio_int, GPIOF_IN,
 760                                    "zforce_ts_int");
 761        if (ret) {
 762                dev_err(&client->dev, "request of gpio %d failed, %d\n",
 763                        pdata->gpio_int, ret);
 764                return ret;
 765        }
 766
 767        ret = devm_gpio_request_one(&client->dev, pdata->gpio_rst,
 768                                    GPIOF_OUT_INIT_LOW, "zforce_ts_rst");
 769        if (ret) {
 770                dev_err(&client->dev, "request of gpio %d failed, %d\n",
 771                        pdata->gpio_rst, ret);
 772                return ret;
 773        }
 774
 775        ts->reg_vdd = devm_regulator_get_optional(&client->dev, "vdd");
 776        if (IS_ERR(ts->reg_vdd)) {
 777                ret = PTR_ERR(ts->reg_vdd);
 778                if (ret == -EPROBE_DEFER)
 779                        return ret;
 780        } else {
 781                ret = regulator_enable(ts->reg_vdd);
 782                if (ret)
 783                        return ret;
 784
 785                /*
 786                 * according to datasheet add 100us grace time after regular
 787                 * regulator enable delay.
 788                 */
 789                udelay(100);
 790        }
 791
 792        ret = devm_add_action(&client->dev, zforce_reset, ts);
 793        if (ret) {
 794                dev_err(&client->dev, "failed to register reset action, %d\n",
 795                        ret);
 796
 797                /* hereafter the regulator will be disabled by the action */
 798                if (!IS_ERR(ts->reg_vdd))
 799                        regulator_disable(ts->reg_vdd);
 800
 801                return ret;
 802        }
 803
 804        snprintf(ts->phys, sizeof(ts->phys),
 805                 "%s/input0", dev_name(&client->dev));
 806
 807        input_dev = devm_input_allocate_device(&client->dev);
 808        if (!input_dev) {
 809                dev_err(&client->dev, "could not allocate input device\n");
 810                return -ENOMEM;
 811        }
 812
 813        mutex_init(&ts->access_mutex);
 814        mutex_init(&ts->command_mutex);
 815
 816        ts->pdata = pdata;
 817        ts->client = client;
 818        ts->input = input_dev;
 819
 820        input_dev->name = "Neonode zForce touchscreen";
 821        input_dev->phys = ts->phys;
 822        input_dev->id.bustype = BUS_I2C;
 823
 824        input_dev->open = zforce_input_open;
 825        input_dev->close = zforce_input_close;
 826
 827        __set_bit(EV_KEY, input_dev->evbit);
 828        __set_bit(EV_SYN, input_dev->evbit);
 829        __set_bit(EV_ABS, input_dev->evbit);
 830
 831        /* For multi touch */
 832        input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
 833                             pdata->x_max, 0, 0);
 834        input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
 835                             pdata->y_max, 0, 0);
 836
 837        input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
 838                             ZFORCE_MAX_AREA, 0, 0);
 839        input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
 840                             ZFORCE_MAX_AREA, 0, 0);
 841        input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
 842        input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
 843
 844        input_set_drvdata(ts->input, ts);
 845
 846        init_completion(&ts->command_done);
 847
 848        /*
 849         * The zforce pulls the interrupt low when it has data ready.
 850         * After it is triggered the isr thread runs until all the available
 851         * packets have been read and the interrupt is high again.
 852         * Therefore we can trigger the interrupt anytime it is low and do
 853         * not need to limit it to the interrupt edge.
 854         */
 855        ret = devm_request_threaded_irq(&client->dev, client->irq,
 856                                        zforce_irq, zforce_irq_thread,
 857                                        IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 858                                        input_dev->name, ts);
 859        if (ret) {
 860                dev_err(&client->dev, "irq %d request failed\n", client->irq);
 861                return ret;
 862        }
 863
 864        i2c_set_clientdata(client, ts);
 865
 866        /* let the controller boot */
 867        gpio_set_value(pdata->gpio_rst, 1);
 868
 869        ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
 870        if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
 871                dev_warn(&client->dev, "bootcomplete timed out\n");
 872
 873        /* need to start device to get version information */
 874        ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
 875        if (ret) {
 876                dev_err(&client->dev, "unable to initialize, %d\n", ret);
 877                return ret;
 878        }
 879
 880        /* this gets the firmware version among other information */
 881        ret = zforce_command_wait(ts, COMMAND_STATUS);
 882        if (ret < 0) {
 883                dev_err(&client->dev, "couldn't get status, %d\n", ret);
 884                zforce_stop(ts);
 885                return ret;
 886        }
 887
 888        /* stop device and put it into sleep until it is opened */
 889        ret = zforce_stop(ts);
 890        if (ret < 0)
 891                return ret;
 892
 893        device_set_wakeup_capable(&client->dev, true);
 894
 895        ret = input_register_device(input_dev);
 896        if (ret) {
 897                dev_err(&client->dev, "could not register input device, %d\n",
 898                        ret);
 899                return ret;
 900        }
 901
 902        return 0;
 903}
 904
 905static struct i2c_device_id zforce_idtable[] = {
 906        { "zforce-ts", 0 },
 907        { }
 908};
 909MODULE_DEVICE_TABLE(i2c, zforce_idtable);
 910
 911#ifdef CONFIG_OF
 912static const struct of_device_id zforce_dt_idtable[] = {
 913        { .compatible = "neonode,zforce" },
 914        {},
 915};
 916MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
 917#endif
 918
 919static struct i2c_driver zforce_driver = {
 920        .driver = {
 921                .owner  = THIS_MODULE,
 922                .name   = "zforce-ts",
 923                .pm     = &zforce_pm_ops,
 924                .of_match_table = of_match_ptr(zforce_dt_idtable),
 925        },
 926        .probe          = zforce_probe,
 927        .id_table       = zforce_idtable,
 928};
 929
 930module_i2c_driver(zforce_driver);
 931
 932MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 933MODULE_DESCRIPTION("zForce TouchScreen Driver");
 934MODULE_LICENSE("GPL");
 935
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