drivers/input/touchscreen/mms114.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Melfas MMS114/MMS152 touchscreen device driver
   3 //
   4 // Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5 // Author: Joonyoung Shim <jy0922.shim@samsung.com>
   6
   7 #include <linux/module.h>
   8 #include <linux/delay.h>
   9 #include <linux/of.h>
  10 #include <linux/of_device.h>
  11 #include <linux/i2c.h>
  12 #include <linux/input/mt.h>
  13 #include <linux/input/touchscreen.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/regulator/consumer.h>
  16 #include <linux/slab.h>
  17
  18 /* Write only registers */
  19 #define MMS114_MODE_CONTROL             0x01
  20 #define MMS114_OPERATION_MODE_MASK      0xE
  21 #define MMS114_ACTIVE                   BIT(1)
  22
  23 #define MMS114_XY_RESOLUTION_H          0x02
  24 #define MMS114_X_RESOLUTION             0x03
  25 #define MMS114_Y_RESOLUTION             0x04
  26 #define MMS114_CONTACT_THRESHOLD        0x05
  27 #define MMS114_MOVING_THRESHOLD         0x06
  28
  29 /* Read only registers */
  30 #define MMS114_PACKET_SIZE              0x0F
  31 #define MMS114_INFORMATION              0x10
  32 #define MMS114_TSP_REV                  0xF0
  33
  34 #define MMS152_FW_REV                   0xE1
  35 #define MMS152_COMPAT_GROUP             0xF2
  36
  37 /* Minimum delay time is 50us between stop and start signal of i2c */
  38 #define MMS114_I2C_DELAY                50
  39
  40 /* 200ms needs after power on */
  41 #define MMS114_POWERON_DELAY            200
  42
  43 /* Touchscreen absolute values */
  44 #define MMS114_MAX_AREA                 0xff
  45
  46 #define MMS114_MAX_TOUCH                10
  47 #define MMS114_PACKET_NUM               8
  48
  49 /* Touch type */
  50 #define MMS114_TYPE_NONE                0
  51 #define MMS114_TYPE_TOUCHSCREEN         1
  52 #define MMS114_TYPE_TOUCHKEY            2
  53
  54 enum mms_type {
  55         TYPE_MMS114     = 114,
  56         TYPE_MMS152     = 152,
  57 };
  58
  59 struct mms114_data {
  60         struct i2c_client       *client;
  61         struct input_dev        *input_dev;
  62         struct regulator        *core_reg;
  63         struct regulator        *io_reg;
  64         struct touchscreen_properties props;
  65         enum mms_type           type;
  66         unsigned int            contact_threshold;
  67         unsigned int            moving_threshold;
  68
  69         /* Use cache data for mode control register(write only) */
  70         u8                      cache_mode_control;
  71 };
  72
  73 struct mms114_touch {
  74         u8 id:4, reserved_bit4:1, type:2, pressed:1;
  75         u8 x_hi:4, y_hi:4;
  76         u8 x_lo;
  77         u8 y_lo;
  78         u8 width;
  79         u8 strength;
  80         u8 reserved[2];
  81 } __packed;
  82
  83 static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
  84                              unsigned int len, u8 *val)
  85 {
  86         struct i2c_client *client = data->client;
  87         struct i2c_msg xfer[2];
  88         u8 buf = reg & 0xff;
  89         int error;
  90
  91         if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
  92                 BUG();
  93
  94         /* Write register: use repeated start */
  95         xfer[0].addr = client->addr;
  96         xfer[0].flags = I2C_M_TEN | I2C_M_NOSTART;
  97         xfer[0].len = 1;
  98         xfer[0].buf = &buf;
  99
 100         /* Read data */
 101         xfer[1].addr = client->addr;
 102         xfer[1].flags = I2C_M_RD;
 103         xfer[1].len = len;
 104         xfer[1].buf = val;
 105
 106         error = i2c_transfer(client->adapter, xfer, 2);
 107         if (error != 2) {
 108                 dev_err(&client->dev,
 109                         "%s: i2c transfer failed (%d)\n", __func__, error);
 110                 return error < 0 ? error : -EIO;
 111         }
 112         udelay(MMS114_I2C_DELAY);
 113
 114         return 0;
 115 }
 116
 117 static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
 118 {
 119         u8 val;
 120         int error;
 121
 122         if (reg == MMS114_MODE_CONTROL)
 123                 return data->cache_mode_control;
 124
 125         error = __mms114_read_reg(data, reg, 1, &val);
 126         return error < 0 ? error : val;
 127 }
 128
 129 static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
 130                             unsigned int val)
 131 {
 132         struct i2c_client *client = data->client;
 133         u8 buf[2];
 134         int error;
 135
 136         buf[0] = reg & 0xff;
 137         buf[1] = val & 0xff;
 138
 139         error = i2c_master_send(client, buf, 2);
 140         if (error != 2) {
 141                 dev_err(&client->dev,
 142                         "%s: i2c send failed (%d)\n", __func__, error);
 143                 return error < 0 ? error : -EIO;
 144         }
 145         udelay(MMS114_I2C_DELAY);
 146
 147         if (reg == MMS114_MODE_CONTROL)
 148                 data->cache_mode_control = val;
 149
 150         return 0;
 151 }
 152
 153 static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
 154 {
 155         struct i2c_client *client = data->client;
 156         struct input_dev *input_dev = data->input_dev;
 157         unsigned int id;
 158         unsigned int x;
 159         unsigned int y;
 160
 161         if (touch->id > MMS114_MAX_TOUCH) {
 162                 dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
 163                 return;
 164         }
 165
 166         if (touch->type != MMS114_TYPE_TOUCHSCREEN) {
 167                 dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type);
 168                 return;
 169         }
 170
 171         id = touch->id - 1;
 172         x = touch->x_lo | touch->x_hi << 8;
 173         y = touch->y_lo | touch->y_hi << 8;
 174
 175         dev_dbg(&client->dev,
 176                 "id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
 177                 id, touch->type, touch->pressed,
 178                 x, y, touch->width, touch->strength);
 179
 180         input_mt_slot(input_dev, id);
 181         input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
 182
 183         if (touch->pressed) {
 184                 touchscreen_report_pos(input_dev, &data->props, x, y, true);
 185                 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
 186                 input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
 187         }
 188 }
 189
 190 static irqreturn_t mms114_interrupt(int irq, void *dev_id)
 191 {
 192         struct mms114_data *data = dev_id;
 193         struct input_dev *input_dev = data->input_dev;
 194         struct mms114_touch touch[MMS114_MAX_TOUCH];
 195         int packet_size;
 196         int touch_size;
 197         int index;
 198         int error;
 199
 200         mutex_lock(&input_dev->mutex);
 201         if (!input_dev->users) {
 202                 mutex_unlock(&input_dev->mutex);
 203                 goto out;
 204         }
 205         mutex_unlock(&input_dev->mutex);
 206
 207         packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
 208         if (packet_size <= 0)
 209                 goto out;
 210
 211         touch_size = packet_size / MMS114_PACKET_NUM;
 212
 213         error = __mms114_read_reg(data, MMS114_INFORMATION, packet_size,
 214                         (u8 *)touch);
 215         if (error < 0)
 216                 goto out;
 217
 218         for (index = 0; index < touch_size; index++)
 219                 mms114_process_mt(data, touch + index);
 220
 221         input_mt_report_pointer_emulation(data->input_dev, true);
 222         input_sync(data->input_dev);
 223
 224 out:
 225         return IRQ_HANDLED;
 226 }
 227
 228 static int mms114_set_active(struct mms114_data *data, bool active)
 229 {
 230         int val;
 231
 232         val = mms114_read_reg(data, MMS114_MODE_CONTROL);
 233         if (val < 0)
 234                 return val;
 235
 236         val &= ~MMS114_OPERATION_MODE_MASK;
 237
 238         /* If active is false, sleep mode */
 239         if (active)
 240                 val |= MMS114_ACTIVE;
 241
 242         return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
 243 }
 244
 245 static int mms114_get_version(struct mms114_data *data)
 246 {
 247         struct device *dev = &data->client->dev;
 248         u8 buf[6];
 249         int group;
 250         int error;
 251
 252         switch (data->type) {
 253         case TYPE_MMS152:
 254                 error = __mms114_read_reg(data, MMS152_FW_REV, 3, buf);
 255                 if (error)
 256                         return error;
 257
 258                 group = i2c_smbus_read_byte_data(data->client,
 259                                                   MMS152_COMPAT_GROUP);
 260                 if (group < 0)
 261                         return group;
 262
 263                 dev_info(dev, "TSP FW Rev: bootloader 0x%x / core 0x%x / config 0x%x, Compat group: %c\n",
 264                          buf[0], buf[1], buf[2], group);
 265                 break;
 266
 267         case TYPE_MMS114:
 268                 error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
 269                 if (error)
 270                         return error;
 271
 272                 dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
 273                          buf[0], buf[1], buf[3]);
 274                 break;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static int mms114_setup_regs(struct mms114_data *data)
 281 {
 282         const struct touchscreen_properties *props = &data->props;
 283         int val;
 284         int error;
 285
 286         error = mms114_get_version(data);
 287         if (error < 0)
 288                 return error;
 289
 290         /* MMS152 has no configuration or power on registers */
 291         if (data->type == TYPE_MMS152)
 292                 return 0;
 293
 294         error = mms114_set_active(data, true);
 295         if (error < 0)
 296                 return error;
 297
 298         val = (props->max_x >> 8) & 0xf;
 299         val |= ((props->max_y >> 8) & 0xf) << 4;
 300         error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
 301         if (error < 0)
 302                 return error;
 303
 304         val = props->max_x & 0xff;
 305         error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
 306         if (error < 0)
 307                 return error;
 308
 309         val = props->max_x & 0xff;
 310         error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
 311         if (error < 0)
 312                 return error;
 313
 314         if (data->contact_threshold) {
 315                 error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
 316                                 data->contact_threshold);
 317                 if (error < 0)
 318                         return error;
 319         }
 320
 321         if (data->moving_threshold) {
 322                 error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
 323                                 data->moving_threshold);
 324                 if (error < 0)
 325                         return error;
 326         }
 327
 328         return 0;
 329 }
 330
 331 static int mms114_start(struct mms114_data *data)
 332 {
 333         struct i2c_client *client = data->client;
 334         int error;
 335
 336         error = regulator_enable(data->core_reg);
 337         if (error) {
 338                 dev_err(&client->dev, "Failed to enable avdd: %d\n", error);
 339                 return error;
 340         }
 341
 342         error = regulator_enable(data->io_reg);
 343         if (error) {
 344                 dev_err(&client->dev, "Failed to enable vdd: %d\n", error);
 345                 regulator_disable(data->core_reg);
 346                 return error;
 347         }
 348
 349         msleep(MMS114_POWERON_DELAY);
 350
 351         error = mms114_setup_regs(data);
 352         if (error < 0) {
 353                 regulator_disable(data->io_reg);
 354                 regulator_disable(data->core_reg);
 355                 return error;
 356         }
 357
 358         enable_irq(client->irq);
 359
 360         return 0;
 361 }
 362
 363 static void mms114_stop(struct mms114_data *data)
 364 {
 365         struct i2c_client *client = data->client;
 366         int error;
 367
 368         disable_irq(client->irq);
 369
 370         error = regulator_disable(data->io_reg);
 371         if (error)
 372                 dev_warn(&client->dev, "Failed to disable vdd: %d\n", error);
 373
 374         error = regulator_disable(data->core_reg);
 375         if (error)
 376                 dev_warn(&client->dev, "Failed to disable avdd: %d\n", error);
 377 }
 378
 379 static int mms114_input_open(struct input_dev *dev)
 380 {
 381         struct mms114_data *data = input_get_drvdata(dev);
 382
 383         return mms114_start(data);
 384 }
 385
 386 static void mms114_input_close(struct input_dev *dev)
 387 {
 388         struct mms114_data *data = input_get_drvdata(dev);
 389
 390         mms114_stop(data);
 391 }
 392
 393 static int mms114_parse_legacy_bindings(struct mms114_data *data)
 394 {
 395         struct device *dev = &data->client->dev;
 396         struct touchscreen_properties *props = &data->props;
 397
 398         if (device_property_read_u32(dev, "x-size", &props->max_x)) {
 399                 dev_dbg(dev, "failed to get legacy x-size property\n");
 400                 return -EINVAL;
 401         }
 402
 403         if (device_property_read_u32(dev, "y-size", &props->max_y)) {
 404                 dev_dbg(dev, "failed to get legacy y-size property\n");
 405                 return -EINVAL;
 406         }
 407
 408         device_property_read_u32(dev, "contact-threshold",
 409                                 &data->contact_threshold);
 410         device_property_read_u32(dev, "moving-threshold",
 411                                 &data->moving_threshold);
 412
 413         if (device_property_read_bool(dev, "x-invert"))
 414                 props->invert_x = true;
 415         if (device_property_read_bool(dev, "y-invert"))
 416                 props->invert_y = true;
 417
 418         props->swap_x_y = false;
 419
 420         return 0;
 421 }
 422
 423 static int mms114_probe(struct i2c_client *client,
 424                                   const struct i2c_device_id *id)
 425 {
 426         struct mms114_data *data;
 427         struct input_dev *input_dev;
 428         const void *match_data;
 429         int error;
 430
 431         if (!i2c_check_functionality(client->adapter,
 432                                 I2C_FUNC_PROTOCOL_MANGLING)) {
 433                 dev_err(&client->dev,
 434                         "Need i2c bus that supports protocol mangling\n");
 435                 return -ENODEV;
 436         }
 437
 438         data = devm_kzalloc(&client->dev, sizeof(struct mms114_data),
 439                             GFP_KERNEL);
 440         input_dev = devm_input_allocate_device(&client->dev);
 441         if (!data || !input_dev) {
 442                 dev_err(&client->dev, "Failed to allocate memory\n");
 443                 return -ENOMEM;
 444         }
 445
 446         data->client = client;
 447         data->input_dev = input_dev;
 448
 449         /* FIXME: switch to device_get_match_data() when available */
 450         match_data = of_device_get_match_data(&client->dev);
 451         if (!match_data)
 452                 return -EINVAL;
 453
 454         data->type = (enum mms_type)match_data;
 455
 456         input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
 457         input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
 458         input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
 459         input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 460                              0, MMS114_MAX_AREA, 0, 0);
 461
 462         touchscreen_parse_properties(input_dev, true, &data->props);
 463         if (!data->props.max_x || !data->props.max_y) {
 464                 dev_dbg(&client->dev,
 465                         "missing X/Y size properties, trying legacy bindings\n");
 466                 error = mms114_parse_legacy_bindings(data);
 467                 if (error)
 468                         return error;
 469
 470                 input_set_abs_params(input_dev, ABS_MT_POSITION_X,
 471                                      0, data->props.max_x, 0, 0);
 472                 input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
 473                                      0, data->props.max_y, 0, 0);
 474         }
 475
 476         if (data->type == TYPE_MMS114) {
 477                 /*
 478                  * The firmware handles movement and pressure fuzz, so
 479                  * don't duplicate that in software.
 480                  */
 481                 data->moving_threshold = input_abs_get_fuzz(input_dev,
 482                                                             ABS_MT_POSITION_X);
 483                 data->contact_threshold = input_abs_get_fuzz(input_dev,
 484                                                              ABS_MT_PRESSURE);
 485                 input_abs_set_fuzz(input_dev, ABS_MT_POSITION_X, 0);
 486                 input_abs_set_fuzz(input_dev, ABS_MT_POSITION_Y, 0);
 487                 input_abs_set_fuzz(input_dev, ABS_MT_PRESSURE, 0);
 488         }
 489
 490         input_dev->name = devm_kasprintf(&client->dev, GFP_KERNEL,
 491                                          "MELFAS MMS%d Touchscreen",
 492                                          data->type);
 493         if (!input_dev->name)
 494                 return -ENOMEM;
 495
 496         input_dev->id.bustype = BUS_I2C;
 497         input_dev->dev.parent = &client->dev;
 498         input_dev->open = mms114_input_open;
 499         input_dev->close = mms114_input_close;
 500
 501         error = input_mt_init_slots(input_dev, MMS114_MAX_TOUCH,
 502                                     INPUT_MT_DIRECT);
 503         if (error)
 504                 return error;
 505
 506         input_set_drvdata(input_dev, data);
 507         i2c_set_clientdata(client, data);
 508
 509         data->core_reg = devm_regulator_get(&client->dev, "avdd");
 510         if (IS_ERR(data->core_reg)) {
 511                 error = PTR_ERR(data->core_reg);
 512                 dev_err(&client->dev,
 513                         "Unable to get the Core regulator (%d)\n", error);
 514                 return error;
 515         }
 516
 517         data->io_reg = devm_regulator_get(&client->dev, "vdd");
 518         if (IS_ERR(data->io_reg)) {
 519                 error = PTR_ERR(data->io_reg);
 520                 dev_err(&client->dev,
 521                         "Unable to get the IO regulator (%d)\n", error);
 522                 return error;
 523         }
 524
 525         error = devm_request_threaded_irq(&client->dev, client->irq,
 526                                           NULL, mms114_interrupt, IRQF_ONESHOT,
 527                                           dev_name(&client->dev), data);
 528         if (error) {
 529                 dev_err(&client->dev, "Failed to register interrupt\n");
 530                 return error;
 531         }
 532         disable_irq(client->irq);
 533
 534         error = input_register_device(data->input_dev);
 535         if (error) {
 536                 dev_err(&client->dev, "Failed to register input device\n");
 537                 return error;
 538         }
 539
 540         return 0;
 541 }
 542
 543 static int __maybe_unused mms114_suspend(struct device *dev)
 544 {
 545         struct i2c_client *client = to_i2c_client(dev);
 546         struct mms114_data *data = i2c_get_clientdata(client);
 547         struct input_dev *input_dev = data->input_dev;
 548         int id;
 549
 550         /* Release all touch */
 551         for (id = 0; id < MMS114_MAX_TOUCH; id++) {
 552                 input_mt_slot(input_dev, id);
 553                 input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false);
 554         }
 555
 556         input_mt_report_pointer_emulation(input_dev, true);
 557         input_sync(input_dev);
 558
 559         mutex_lock(&input_dev->mutex);
 560         if (input_dev->users)
 561                 mms114_stop(data);
 562         mutex_unlock(&input_dev->mutex);
 563
 564         return 0;
 565 }
 566
 567 static int __maybe_unused mms114_resume(struct device *dev)
 568 {
 569         struct i2c_client *client = to_i2c_client(dev);
 570         struct mms114_data *data = i2c_get_clientdata(client);
 571         struct input_dev *input_dev = data->input_dev;
 572         int error;
 573
 574         mutex_lock(&input_dev->mutex);
 575         if (input_dev->users) {
 576                 error = mms114_start(data);
 577                 if (error < 0) {
 578                         mutex_unlock(&input_dev->mutex);
 579                         return error;
 580                 }
 581         }
 582         mutex_unlock(&input_dev->mutex);
 583
 584         return 0;
 585 }
 586
 587 static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
 588
 589 static const struct i2c_device_id mms114_id[] = {
 590         { "mms114", 0 },
 591         { }
 592 };
 593 MODULE_DEVICE_TABLE(i2c, mms114_id);
 594
 595 #ifdef CONFIG_OF
 596 static const struct of_device_id mms114_dt_match[] = {
 597         {
 598                 .compatible = "melfas,mms114",
 599                 .data = (void *)TYPE_MMS114,
 600         }, {
 601                 .compatible = "melfas,mms152",
 602                 .data = (void *)TYPE_MMS152,
 603         },
 604         { }
 605 };
 606 MODULE_DEVICE_TABLE(of, mms114_dt_match);
 607 #endif
 608
 609 static struct i2c_driver mms114_driver = {
 610         .driver = {
 611                 .name   = "mms114",
 612                 .pm     = &mms114_pm_ops,
 613                 .of_match_table = of_match_ptr(mms114_dt_match),
 614         },
 615         .probe          = mms114_probe,
 616         .id_table       = mms114_id,
 617 };
 618
 619 module_i2c_driver(mms114_driver);
 620
 621 /* Module information */
 622 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
 623 MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
 624 MODULE_LICENSE("GPL v2");