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