linux/drivers/input/touchscreen/zforce_ts.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2012-2013 MundoReader S.L.
   4 * Author: Heiko Stuebner <heiko@sntech.de>
   5 *
   6 * based in parts on Nook zforce driver
   7 *
   8 * Copyright (C) 2010 Barnes & Noble, Inc.
   9 * Author: Pieter Truter<ptruter@intrinsyc.com>
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/hrtimer.h>
  14#include <linux/slab.h>
  15#include <linux/input.h>
  16#include <linux/interrupt.h>
  17#include <linux/i2c.h>
  18#include <linux/delay.h>
  19#include <linux/gpio/consumer.h>
  20#include <linux/device.h>
  21#include <linux/sysfs.h>
  22#include <linux/input/mt.h>
  23#include <linux/platform_data/zforce_ts.h>
  24#include <linux/regulator/consumer.h>
  25#include <linux/of.h>
  26
  27#define WAIT_TIMEOUT            msecs_to_jiffies(1000)
  28
  29#define FRAME_START             0xee
  30#define FRAME_MAXSIZE           257
  31
  32/* Offsets of the different parts of the payload the controller sends */
  33#define PAYLOAD_HEADER          0
  34#define PAYLOAD_LENGTH          1
  35#define PAYLOAD_BODY            2
  36
  37/* Response offsets */
  38#define RESPONSE_ID             0
  39#define RESPONSE_DATA           1
  40
  41/* Commands */
  42#define COMMAND_DEACTIVATE      0x00
  43#define COMMAND_INITIALIZE      0x01
  44#define COMMAND_RESOLUTION      0x02
  45#define COMMAND_SETCONFIG       0x03
  46#define COMMAND_DATAREQUEST     0x04
  47#define COMMAND_SCANFREQ        0x08
  48#define COMMAND_STATUS          0X1e
  49
  50/*
  51 * Responses the controller sends as a result of
  52 * command requests
  53 */
  54#define RESPONSE_DEACTIVATE     0x00
  55#define RESPONSE_INITIALIZE     0x01
  56#define RESPONSE_RESOLUTION     0x02
  57#define RESPONSE_SETCONFIG      0x03
  58#define RESPONSE_SCANFREQ       0x08
  59#define RESPONSE_STATUS         0X1e
  60
  61/*
  62 * Notifications are sent by the touch controller without
  63 * being requested by the driver and include for example
  64 * touch indications
  65 */
  66#define NOTIFICATION_TOUCH              0x04
  67#define NOTIFICATION_BOOTCOMPLETE       0x07
  68#define NOTIFICATION_OVERRUN            0x25
  69#define NOTIFICATION_PROXIMITY          0x26
  70#define NOTIFICATION_INVALID_COMMAND    0xfe
  71
  72#define ZFORCE_REPORT_POINTS            2
  73#define ZFORCE_MAX_AREA                 0xff
  74
  75#define STATE_DOWN                      0
  76#define STATE_MOVE                      1
  77#define STATE_UP                        2
  78
  79#define SETCONFIG_DUALTOUCH             (1 << 0)
  80
  81struct zforce_point {
  82        int coord_x;
  83        int coord_y;
  84        int state;
  85        int id;
  86        int area_major;
  87        int area_minor;
  88        int orientation;
  89        int pressure;
  90        int prblty;
  91};
  92
  93/*
  94 * @client              the i2c_client
  95 * @input               the input device
  96 * @suspending          in the process of going to suspend (don't emit wakeup
  97 *                      events for commands executed to suspend the device)
  98 * @suspended           device suspended
  99 * @access_mutex        serialize i2c-access, to keep multipart reads together
 100 * @command_done        completion to wait for the command result
 101 * @command_mutex       serialize commands sent to the ic
 102 * @command_waiting     the id of the command that is currently waiting
 103 *                      for a result
 104 * @command_result      returned result of the command
 105 */
 106struct zforce_ts {
 107        struct i2c_client       *client;
 108        struct input_dev        *input;
 109        const struct zforce_ts_platdata *pdata;
 110        char                    phys[32];
 111
 112        struct regulator        *reg_vdd;
 113
 114        struct gpio_desc        *gpio_int;
 115        struct gpio_desc        *gpio_rst;
 116
 117        bool                    suspending;
 118        bool                    suspended;
 119        bool                    boot_complete;
 120
 121        /* Firmware version information */
 122        u16                     version_major;
 123        u16                     version_minor;
 124        u16                     version_build;
 125        u16                     version_rev;
 126
 127        struct mutex            access_mutex;
 128
 129        struct completion       command_done;
 130        struct mutex            command_mutex;
 131        int                     command_waiting;
 132        int                     command_result;
 133};
 134
 135static int zforce_command(struct zforce_ts *ts, u8 cmd)
 136{
 137        struct i2c_client *client = ts->client;
 138        char buf[3];
 139        int ret;
 140
 141        dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
 142
 143        buf[0] = FRAME_START;
 144        buf[1] = 1; /* data size, command only */
 145        buf[2] = cmd;
 146
 147        mutex_lock(&ts->access_mutex);
 148        ret = i2c_master_send(client, &buf[0], ARRAY_SIZE(buf));
 149        mutex_unlock(&ts->access_mutex);
 150        if (ret < 0) {
 151                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 152                return ret;
 153        }
 154
 155        return 0;
 156}
 157
 158static void zforce_reset_assert(struct zforce_ts *ts)
 159{
 160        gpiod_set_value_cansleep(ts->gpio_rst, 1);
 161}
 162
 163static void zforce_reset_deassert(struct zforce_ts *ts)
 164{
 165        gpiod_set_value_cansleep(ts->gpio_rst, 0);
 166}
 167
 168static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
 169{
 170        struct i2c_client *client = ts->client;
 171        int ret;
 172
 173        ret = mutex_trylock(&ts->command_mutex);
 174        if (!ret) {
 175                dev_err(&client->dev, "already waiting for a command\n");
 176                return -EBUSY;
 177        }
 178
 179        dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
 180                buf[1], buf[2]);
 181
 182        ts->command_waiting = buf[2];
 183
 184        mutex_lock(&ts->access_mutex);
 185        ret = i2c_master_send(client, buf, len);
 186        mutex_unlock(&ts->access_mutex);
 187        if (ret < 0) {
 188                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 189                goto unlock;
 190        }
 191
 192        dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
 193
 194        if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0) {
 195                ret = -ETIME;
 196                goto unlock;
 197        }
 198
 199        ret = ts->command_result;
 200
 201unlock:
 202        mutex_unlock(&ts->command_mutex);
 203        return ret;
 204}
 205
 206static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
 207{
 208        struct i2c_client *client = ts->client;
 209        char buf[3];
 210        int ret;
 211
 212        dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
 213
 214        buf[0] = FRAME_START;
 215        buf[1] = 1; /* data size, command only */
 216        buf[2] = cmd;
 217
 218        ret = zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 219        if (ret < 0) {
 220                dev_err(&client->dev, "i2c send data request error: %d\n", ret);
 221                return ret;
 222        }
 223
 224        return 0;
 225}
 226
 227static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
 228{
 229        struct i2c_client *client = ts->client;
 230        char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
 231                        (x & 0xff), ((x >> 8) & 0xff),
 232                        (y & 0xff), ((y >> 8) & 0xff) };
 233
 234        dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
 235
 236        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 237}
 238
 239static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
 240                                 u16 stylus)
 241{
 242        struct i2c_client *client = ts->client;
 243        char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
 244                        (idle & 0xff), ((idle >> 8) & 0xff),
 245                        (finger & 0xff), ((finger >> 8) & 0xff),
 246                        (stylus & 0xff), ((stylus >> 8) & 0xff) };
 247
 248        dev_dbg(&client->dev,
 249                "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
 250                idle, finger, stylus);
 251
 252        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 253}
 254
 255static int zforce_setconfig(struct zforce_ts *ts, char b1)
 256{
 257        struct i2c_client *client = ts->client;
 258        char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
 259                        b1, 0, 0, 0 };
 260
 261        dev_dbg(&client->dev, "set config to (%d)\n", b1);
 262
 263        return zforce_send_wait(ts, &buf[0], ARRAY_SIZE(buf));
 264}
 265
 266static int zforce_start(struct zforce_ts *ts)
 267{
 268        struct i2c_client *client = ts->client;
 269        const struct zforce_ts_platdata *pdata = ts->pdata;
 270        int ret;
 271
 272        dev_dbg(&client->dev, "starting device\n");
 273
 274        ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
 275        if (ret) {
 276                dev_err(&client->dev, "Unable to initialize, %d\n", ret);
 277                return ret;
 278        }
 279
 280        ret = zforce_resolution(ts, pdata->x_max, pdata->y_max);
 281        if (ret) {
 282                dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
 283                goto error;
 284        }
 285
 286        ret = zforce_scan_frequency(ts, 10, 50, 50);
 287        if (ret) {
 288                dev_err(&client->dev, "Unable to set scan frequency, %d\n",
 289                        ret);
 290                goto error;
 291        }
 292
 293        ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
 294        if (ret) {
 295                dev_err(&client->dev, "Unable to set config\n");
 296                goto error;
 297        }
 298
 299        /* start sending touch events */
 300        ret = zforce_command(ts, COMMAND_DATAREQUEST);
 301        if (ret) {
 302                dev_err(&client->dev, "Unable to request data\n");
 303                goto error;
 304        }
 305
 306        /*
 307         * Per NN, initial cal. take max. of 200msec.
 308         * Allow time to complete this calibration
 309         */
 310        msleep(200);
 311
 312        return 0;
 313
 314error:
 315        zforce_command_wait(ts, COMMAND_DEACTIVATE);
 316        return ret;
 317}
 318
 319static int zforce_stop(struct zforce_ts *ts)
 320{
 321        struct i2c_client *client = ts->client;
 322        int ret;
 323
 324        dev_dbg(&client->dev, "stopping device\n");
 325
 326        /* Deactivates touch sensing and puts the device into sleep. */
 327        ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
 328        if (ret != 0) {
 329                dev_err(&client->dev, "could not deactivate device, %d\n",
 330                        ret);
 331                return ret;
 332        }
 333
 334        return 0;
 335}
 336
 337static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
 338{
 339        struct i2c_client *client = ts->client;
 340        const struct zforce_ts_platdata *pdata = ts->pdata;
 341        struct zforce_point point;
 342        int count, i, num = 0;
 343
 344        count = payload[0];
 345        if (count > ZFORCE_REPORT_POINTS) {
 346                dev_warn(&client->dev,
 347                         "too many coordinates %d, expected max %d\n",
 348                         count, ZFORCE_REPORT_POINTS);
 349                count = ZFORCE_REPORT_POINTS;
 350        }
 351
 352        for (i = 0; i < count; i++) {
 353                point.coord_x =
 354                        payload[9 * i + 2] << 8 | payload[9 * i + 1];
 355                point.coord_y =
 356                        payload[9 * i + 4] << 8 | payload[9 * i + 3];
 357
 358                if (point.coord_x > pdata->x_max ||
 359                    point.coord_y > pdata->y_max) {
 360                        dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
 361                                point.coord_x, point.coord_y);
 362                        point.coord_x = point.coord_y = 0;
 363                }
 364
 365                point.state = payload[9 * i + 5] & 0x0f;
 366                point.id = (payload[9 * i + 5] & 0xf0) >> 4;
 367
 368                /* determine touch major, minor and orientation */
 369                point.area_major = max(payload[9 * i + 6],
 370                                          payload[9 * i + 7]);
 371                point.area_minor = min(payload[9 * i + 6],
 372                                          payload[9 * i + 7]);
 373                point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
 374
 375                point.pressure = payload[9 * i + 8];
 376                point.prblty = payload[9 * i + 9];
 377
 378                dev_dbg(&client->dev,
 379                        "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
 380                        i, count, point.state, point.id,
 381                        point.pressure, point.prblty,
 382                        point.coord_x, point.coord_y,
 383                        point.area_major, point.area_minor,
 384                        point.orientation);
 385
 386                /* the zforce id starts with "1", so needs to be decreased */
 387                input_mt_slot(ts->input, point.id - 1);
 388
 389                input_mt_report_slot_state(ts->input, MT_TOOL_FINGER,
 390                                                point.state != STATE_UP);
 391
 392                if (point.state != STATE_UP) {
 393                        input_report_abs(ts->input, ABS_MT_POSITION_X,
 394                                         point.coord_x);
 395                        input_report_abs(ts->input, ABS_MT_POSITION_Y,
 396                                         point.coord_y);
 397                        input_report_abs(ts->input, ABS_MT_TOUCH_MAJOR,
 398                                         point.area_major);
 399                        input_report_abs(ts->input, ABS_MT_TOUCH_MINOR,
 400                                         point.area_minor);
 401                        input_report_abs(ts->input, ABS_MT_ORIENTATION,
 402                                         point.orientation);
 403                        num++;
 404                }
 405        }
 406
 407        input_mt_sync_frame(ts->input);
 408
 409        input_mt_report_finger_count(ts->input, num);
 410
 411        input_sync(ts->input);
 412
 413        return 0;
 414}
 415
 416static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
 417{
 418        struct i2c_client *client = ts->client;
 419        int ret;
 420
 421        mutex_lock(&ts->access_mutex);
 422
 423        /* read 2 byte message header */
 424        ret = i2c_master_recv(client, buf, 2);
 425        if (ret < 0) {
 426                dev_err(&client->dev, "error reading header: %d\n", ret);
 427                goto unlock;
 428        }
 429
 430        if (buf[PAYLOAD_HEADER] != FRAME_START) {
 431                dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
 432                ret = -EIO;
 433                goto unlock;
 434        }
 435
 436        if (buf[PAYLOAD_LENGTH] == 0) {
 437                dev_err(&client->dev, "invalid payload length: %d\n",
 438                        buf[PAYLOAD_LENGTH]);
 439                ret = -EIO;
 440                goto unlock;
 441        }
 442
 443        /* read the message */
 444        ret = i2c_master_recv(client, &buf[PAYLOAD_BODY], buf[PAYLOAD_LENGTH]);
 445        if (ret < 0) {
 446                dev_err(&client->dev, "error reading payload: %d\n", ret);
 447                goto unlock;
 448        }
 449
 450        dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
 451                buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
 452
 453unlock:
 454        mutex_unlock(&ts->access_mutex);
 455        return ret;
 456}
 457
 458static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
 459{
 460        struct i2c_client *client = ts->client;
 461
 462        if (ts->command_waiting == cmd) {
 463                dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
 464                ts->command_result = result;
 465                complete(&ts->command_done);
 466        } else {
 467                dev_dbg(&client->dev, "command %d not for us\n", cmd);
 468        }
 469}
 470
 471static irqreturn_t zforce_irq(int irq, void *dev_id)
 472{
 473        struct zforce_ts *ts = dev_id;
 474        struct i2c_client *client = ts->client;
 475
 476        if (ts->suspended && device_may_wakeup(&client->dev))
 477                pm_wakeup_event(&client->dev, 500);
 478
 479        return IRQ_WAKE_THREAD;
 480}
 481
 482static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
 483{
 484        struct zforce_ts *ts = dev_id;
 485        struct i2c_client *client = ts->client;
 486        int ret;
 487        u8 payload_buffer[FRAME_MAXSIZE];
 488        u8 *payload;
 489
 490        /*
 491         * When still suspended, return.
 492         * Due to the level-interrupt we will get re-triggered later.
 493         */
 494        if (ts->suspended) {
 495                msleep(20);
 496                return IRQ_HANDLED;
 497        }
 498
 499        dev_dbg(&client->dev, "handling interrupt\n");
 500
 501        /* Don't emit wakeup events from commands run by zforce_suspend */
 502        if (!ts->suspending && device_may_wakeup(&client->dev))
 503                pm_stay_awake(&client->dev);
 504
 505        /*
 506         * Run at least once and exit the loop if
 507         * - the optional interrupt GPIO isn't specified
 508         *   (there is only one packet read per ISR invocation, then)
 509         * or
 510         * - the GPIO isn't active any more
 511         *   (packet read until the level GPIO indicates that there is
 512         *    no IRQ any more)
 513         */
 514        do {
 515                ret = zforce_read_packet(ts, payload_buffer);
 516                if (ret < 0) {
 517                        dev_err(&client->dev,
 518                                "could not read packet, ret: %d\n", ret);
 519                        break;
 520                }
 521
 522                payload =  &payload_buffer[PAYLOAD_BODY];
 523
 524                switch (payload[RESPONSE_ID]) {
 525                case NOTIFICATION_TOUCH:
 526                        /*
 527                         * Always report touch-events received while
 528                         * suspending, when being a wakeup source
 529                         */
 530                        if (ts->suspending && device_may_wakeup(&client->dev))
 531                                pm_wakeup_event(&client->dev, 500);
 532                        zforce_touch_event(ts, &payload[RESPONSE_DATA]);
 533                        break;
 534
 535                case NOTIFICATION_BOOTCOMPLETE:
 536                        ts->boot_complete = payload[RESPONSE_DATA];
 537                        zforce_complete(ts, payload[RESPONSE_ID], 0);
 538                        break;
 539
 540                case RESPONSE_INITIALIZE:
 541                case RESPONSE_DEACTIVATE:
 542                case RESPONSE_SETCONFIG:
 543                case RESPONSE_RESOLUTION:
 544                case RESPONSE_SCANFREQ:
 545                        zforce_complete(ts, payload[RESPONSE_ID],
 546                                        payload[RESPONSE_DATA]);
 547                        break;
 548
 549                case RESPONSE_STATUS:
 550                        /*
 551                         * Version Payload Results
 552                         * [2:major] [2:minor] [2:build] [2:rev]
 553                         */
 554                        ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
 555                                                payload[RESPONSE_DATA];
 556                        ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
 557                                                payload[RESPONSE_DATA + 2];
 558                        ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
 559                                                payload[RESPONSE_DATA + 4];
 560                        ts->version_rev   = (payload[RESPONSE_DATA + 7] << 8) |
 561                                                payload[RESPONSE_DATA + 6];
 562                        dev_dbg(&ts->client->dev,
 563                                "Firmware Version %04x:%04x %04x:%04x\n",
 564                                ts->version_major, ts->version_minor,
 565                                ts->version_build, ts->version_rev);
 566
 567                        zforce_complete(ts, payload[RESPONSE_ID], 0);
 568                        break;
 569
 570                case NOTIFICATION_INVALID_COMMAND:
 571                        dev_err(&ts->client->dev, "invalid command: 0x%x\n",
 572                                payload[RESPONSE_DATA]);
 573                        break;
 574
 575                default:
 576                        dev_err(&ts->client->dev,
 577                                "unrecognized response id: 0x%x\n",
 578                                payload[RESPONSE_ID]);
 579                        break;
 580                }
 581        } while (gpiod_get_value_cansleep(ts->gpio_int));
 582
 583        if (!ts->suspending && device_may_wakeup(&client->dev))
 584                pm_relax(&client->dev);
 585
 586        dev_dbg(&client->dev, "finished interrupt\n");
 587
 588        return IRQ_HANDLED;
 589}
 590
 591static int zforce_input_open(struct input_dev *dev)
 592{
 593        struct zforce_ts *ts = input_get_drvdata(dev);
 594
 595        return zforce_start(ts);
 596}
 597
 598static void zforce_input_close(struct input_dev *dev)
 599{
 600        struct zforce_ts *ts = input_get_drvdata(dev);
 601        struct i2c_client *client = ts->client;
 602        int ret;
 603
 604        ret = zforce_stop(ts);
 605        if (ret)
 606                dev_warn(&client->dev, "stopping zforce failed\n");
 607
 608        return;
 609}
 610
 611static int __maybe_unused zforce_suspend(struct device *dev)
 612{
 613        struct i2c_client *client = to_i2c_client(dev);
 614        struct zforce_ts *ts = i2c_get_clientdata(client);
 615        struct input_dev *input = ts->input;
 616        int ret = 0;
 617
 618        mutex_lock(&input->mutex);
 619        ts->suspending = true;
 620
 621        /*
 622         * When configured as a wakeup source device should always wake
 623         * the system, therefore start device if necessary.
 624         */
 625        if (device_may_wakeup(&client->dev)) {
 626                dev_dbg(&client->dev, "suspend while being a wakeup source\n");
 627
 628                /* Need to start device, if not open, to be a wakeup source. */
 629                if (!input->users) {
 630                        ret = zforce_start(ts);
 631                        if (ret)
 632                                goto unlock;
 633                }
 634
 635                enable_irq_wake(client->irq);
 636        } else if (input->users) {
 637                dev_dbg(&client->dev,
 638                        "suspend without being a wakeup source\n");
 639
 640                ret = zforce_stop(ts);
 641                if (ret)
 642                        goto unlock;
 643
 644                disable_irq(client->irq);
 645        }
 646
 647        ts->suspended = true;
 648
 649unlock:
 650        ts->suspending = false;
 651        mutex_unlock(&input->mutex);
 652
 653        return ret;
 654}
 655
 656static int __maybe_unused zforce_resume(struct device *dev)
 657{
 658        struct i2c_client *client = to_i2c_client(dev);
 659        struct zforce_ts *ts = i2c_get_clientdata(client);
 660        struct input_dev *input = ts->input;
 661        int ret = 0;
 662
 663        mutex_lock(&input->mutex);
 664
 665        ts->suspended = false;
 666
 667        if (device_may_wakeup(&client->dev)) {
 668                dev_dbg(&client->dev, "resume from being a wakeup source\n");
 669
 670                disable_irq_wake(client->irq);
 671
 672                /* need to stop device if it was not open on suspend */
 673                if (!input->users) {
 674                        ret = zforce_stop(ts);
 675                        if (ret)
 676                                goto unlock;
 677                }
 678        } else if (input->users) {
 679                dev_dbg(&client->dev, "resume without being a wakeup source\n");
 680
 681                enable_irq(client->irq);
 682
 683                ret = zforce_start(ts);
 684                if (ret < 0)
 685                        goto unlock;
 686        }
 687
 688unlock:
 689        mutex_unlock(&input->mutex);
 690
 691        return ret;
 692}
 693
 694static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
 695
 696static void zforce_reset(void *data)
 697{
 698        struct zforce_ts *ts = data;
 699
 700        zforce_reset_assert(ts);
 701
 702        udelay(10);
 703
 704        if (!IS_ERR(ts->reg_vdd))
 705                regulator_disable(ts->reg_vdd);
 706}
 707
 708static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
 709{
 710        struct zforce_ts_platdata *pdata;
 711        struct device_node *np = dev->of_node;
 712
 713        if (!np)
 714                return ERR_PTR(-ENOENT);
 715
 716        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 717        if (!pdata) {
 718                dev_err(dev, "failed to allocate platform data\n");
 719                return ERR_PTR(-ENOMEM);
 720        }
 721
 722        if (of_property_read_u32(np, "x-size", &pdata->x_max)) {
 723                dev_err(dev, "failed to get x-size property\n");
 724                return ERR_PTR(-EINVAL);
 725        }
 726
 727        if (of_property_read_u32(np, "y-size", &pdata->y_max)) {
 728                dev_err(dev, "failed to get y-size property\n");
 729                return ERR_PTR(-EINVAL);
 730        }
 731
 732        return pdata;
 733}
 734
 735static int zforce_probe(struct i2c_client *client,
 736                        const struct i2c_device_id *id)
 737{
 738        const struct zforce_ts_platdata *pdata = dev_get_platdata(&client->dev);
 739        struct zforce_ts *ts;
 740        struct input_dev *input_dev;
 741        int ret;
 742
 743        if (!pdata) {
 744                pdata = zforce_parse_dt(&client->dev);
 745                if (IS_ERR(pdata))
 746                        return PTR_ERR(pdata);
 747        }
 748
 749        ts = devm_kzalloc(&client->dev, sizeof(struct zforce_ts), GFP_KERNEL);
 750        if (!ts)
 751                return -ENOMEM;
 752
 753        ts->gpio_rst = devm_gpiod_get_optional(&client->dev, "reset",
 754                                               GPIOD_OUT_HIGH);
 755        if (IS_ERR(ts->gpio_rst)) {
 756                ret = PTR_ERR(ts->gpio_rst);
 757                dev_err(&client->dev,
 758                        "failed to request reset GPIO: %d\n", ret);
 759                return ret;
 760        }
 761
 762        if (ts->gpio_rst) {
 763                ts->gpio_int = devm_gpiod_get_optional(&client->dev, "irq",
 764                                                       GPIOD_IN);
 765                if (IS_ERR(ts->gpio_int)) {
 766                        ret = PTR_ERR(ts->gpio_int);
 767                        dev_err(&client->dev,
 768                                "failed to request interrupt GPIO: %d\n", ret);
 769                        return ret;
 770                }
 771        } else {
 772                /*
 773                 * Deprecated GPIO handling for compatibility
 774                 * with legacy binding.
 775                 */
 776
 777                /* INT GPIO */
 778                ts->gpio_int = devm_gpiod_get_index(&client->dev, NULL, 0,
 779                                                    GPIOD_IN);
 780                if (IS_ERR(ts->gpio_int)) {
 781                        ret = PTR_ERR(ts->gpio_int);
 782                        dev_err(&client->dev,
 783                                "failed to request interrupt GPIO: %d\n", ret);
 784                        return ret;
 785                }
 786
 787                /* RST GPIO */
 788                ts->gpio_rst = devm_gpiod_get_index(&client->dev, NULL, 1,
 789                                            GPIOD_OUT_HIGH);
 790                if (IS_ERR(ts->gpio_rst)) {
 791                        ret = PTR_ERR(ts->gpio_rst);
 792                        dev_err(&client->dev,
 793                                "failed to request reset GPIO: %d\n", ret);
 794                        return ret;
 795                }
 796        }
 797
 798        ts->reg_vdd = devm_regulator_get_optional(&client->dev, "vdd");
 799        if (IS_ERR(ts->reg_vdd)) {
 800                ret = PTR_ERR(ts->reg_vdd);
 801                if (ret == -EPROBE_DEFER)
 802                        return ret;
 803        } else {
 804                ret = regulator_enable(ts->reg_vdd);
 805                if (ret)
 806                        return ret;
 807
 808                /*
 809                 * according to datasheet add 100us grace time after regular
 810                 * regulator enable delay.
 811                 */
 812                udelay(100);
 813        }
 814
 815        ret = devm_add_action(&client->dev, zforce_reset, ts);
 816        if (ret) {
 817                dev_err(&client->dev, "failed to register reset action, %d\n",
 818                        ret);
 819
 820                /* hereafter the regulator will be disabled by the action */
 821                if (!IS_ERR(ts->reg_vdd))
 822                        regulator_disable(ts->reg_vdd);
 823
 824                return ret;
 825        }
 826
 827        snprintf(ts->phys, sizeof(ts->phys),
 828                 "%s/input0", dev_name(&client->dev));
 829
 830        input_dev = devm_input_allocate_device(&client->dev);
 831        if (!input_dev) {
 832                dev_err(&client->dev, "could not allocate input device\n");
 833                return -ENOMEM;
 834        }
 835
 836        mutex_init(&ts->access_mutex);
 837        mutex_init(&ts->command_mutex);
 838
 839        ts->pdata = pdata;
 840        ts->client = client;
 841        ts->input = input_dev;
 842
 843        input_dev->name = "Neonode zForce touchscreen";
 844        input_dev->phys = ts->phys;
 845        input_dev->id.bustype = BUS_I2C;
 846
 847        input_dev->open = zforce_input_open;
 848        input_dev->close = zforce_input_close;
 849
 850        __set_bit(EV_KEY, input_dev->evbit);
 851        __set_bit(EV_SYN, input_dev->evbit);
 852        __set_bit(EV_ABS, input_dev->evbit);
 853
 854        /* For multi touch */
 855        input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
 856                             pdata->x_max, 0, 0);
 857        input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
 858                             pdata->y_max, 0, 0);
 859
 860        input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
 861                             ZFORCE_MAX_AREA, 0, 0);
 862        input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR, 0,
 863                             ZFORCE_MAX_AREA, 0, 0);
 864        input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
 865        input_mt_init_slots(input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
 866
 867        input_set_drvdata(ts->input, ts);
 868
 869        init_completion(&ts->command_done);
 870
 871        /*
 872         * The zforce pulls the interrupt low when it has data ready.
 873         * After it is triggered the isr thread runs until all the available
 874         * packets have been read and the interrupt is high again.
 875         * Therefore we can trigger the interrupt anytime it is low and do
 876         * not need to limit it to the interrupt edge.
 877         */
 878        ret = devm_request_threaded_irq(&client->dev, client->irq,
 879                                        zforce_irq, zforce_irq_thread,
 880                                        IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 881                                        input_dev->name, ts);
 882        if (ret) {
 883                dev_err(&client->dev, "irq %d request failed\n", client->irq);
 884                return ret;
 885        }
 886
 887        i2c_set_clientdata(client, ts);
 888
 889        /* let the controller boot */
 890        zforce_reset_deassert(ts);
 891
 892        ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
 893        if (wait_for_completion_timeout(&ts->command_done, WAIT_TIMEOUT) == 0)
 894                dev_warn(&client->dev, "bootcomplete timed out\n");
 895
 896        /* need to start device to get version information */
 897        ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
 898        if (ret) {
 899                dev_err(&client->dev, "unable to initialize, %d\n", ret);
 900                return ret;
 901        }
 902
 903        /* this gets the firmware version among other information */
 904        ret = zforce_command_wait(ts, COMMAND_STATUS);
 905        if (ret < 0) {
 906                dev_err(&client->dev, "couldn't get status, %d\n", ret);
 907                zforce_stop(ts);
 908                return ret;
 909        }
 910
 911        /* stop device and put it into sleep until it is opened */
 912        ret = zforce_stop(ts);
 913        if (ret < 0)
 914                return ret;
 915
 916        device_set_wakeup_capable(&client->dev, true);
 917
 918        ret = input_register_device(input_dev);
 919        if (ret) {
 920                dev_err(&client->dev, "could not register input device, %d\n",
 921                        ret);
 922                return ret;
 923        }
 924
 925        return 0;
 926}
 927
 928static struct i2c_device_id zforce_idtable[] = {
 929        { "zforce-ts", 0 },
 930        { }
 931};
 932MODULE_DEVICE_TABLE(i2c, zforce_idtable);
 933
 934#ifdef CONFIG_OF
 935static const struct of_device_id zforce_dt_idtable[] = {
 936        { .compatible = "neonode,zforce" },
 937        {},
 938};
 939MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
 940#endif
 941
 942static struct i2c_driver zforce_driver = {
 943        .driver = {
 944                .name   = "zforce-ts",
 945                .pm     = &zforce_pm_ops,
 946                .of_match_table = of_match_ptr(zforce_dt_idtable),
 947        },
 948        .probe          = zforce_probe,
 949        .id_table       = zforce_idtable,
 950};
 951
 952module_i2c_driver(zforce_driver);
 953
 954MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 955MODULE_DESCRIPTION("zForce TouchScreen Driver");
 956MODULE_LICENSE("GPL");
 957