drivers/input/touchscreen/zforce_ts.c

   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
  81 struct 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  */
 106 struct 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
 135 static 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
 158 static void zforce_reset_assert(struct zforce_ts *ts)
 159 {
 160         gpiod_set_value_cansleep(ts->gpio_rst, 1);
 161 }
 162
 163 static void zforce_reset_deassert(struct zforce_ts *ts)
 164 {
 165         gpiod_set_value_cansleep(ts->gpio_rst, 0);
 166 }
 167
 168 static 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
 201 unlock:
 202         mutex_unlock(&ts->command_mutex);
 203         return ret;
 204 }
 205
 206 static 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
 227 static 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
 239 static 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
 255 static 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
 266 static 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
 314 error:
 315         zforce_command_wait(ts, COMMAND_DEACTIVATE);
 316         return ret;
 317 }
 318
 319 static 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
 337 static 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
 416 static 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
 453 unlock:
 454         mutex_unlock(&ts->access_mutex);
 455         return ret;
 456 }
 457
 458 static 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
 471 static 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
 482 static 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
 591 static 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
 598 static 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
 611 static 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
 649 unlock:
 650         ts->suspending = false;
 651         mutex_unlock(&input->mutex);
 652
 653         return ret;
 654 }
 655
 656 static 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
 688 unlock:
 689         mutex_unlock(&input->mutex);
 690
 691         return ret;
 692 }
 693
 694 static SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
 695
 696 static 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
 708 static 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
 735 static 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
 928 static struct i2c_device_id zforce_idtable[] = {
 929         { "zforce-ts", 0 },
 930         { }
 931 };
 932 MODULE_DEVICE_TABLE(i2c, zforce_idtable);
 933
 934 #ifdef CONFIG_OF
 935 static const struct of_device_id zforce_dt_idtable[] = {
 936         { .compatible = "neonode,zforce" },
 937         {},
 938 };
 939 MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
 940 #endif
 941
 942 static 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
 952 module_i2c_driver(zforce_driver);
 953
 954 MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
 955 MODULE_DESCRIPTION("zForce TouchScreen Driver");
 956 MODULE_LICENSE("GPL");