drivers/input/touchscreen/zforce_ts.c

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