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