drivers/input/touchscreen/mms114.c

   1 /*
   2  * Copyright (C) 2012 Samsung Electronics Co.Ltd
   3  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/delay.h>
  12 #include <linux/of.h>
  13 #include <linux/i2c.h>
  14 #include <linux/i2c/mms114.h>
  15 #include <linux/input/mt.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/regulator/consumer.h>
  18 #include <linux/slab.h>
  19
  20 /* Write only registers */
  21 #define MMS114_MODE_CONTROL             0x01
  22 #define MMS114_OPERATION_MODE_MASK      0xE
  23 #define MMS114_ACTIVE                   (1 << 1)
  24
  25 #define MMS114_XY_RESOLUTION_H          0x02
  26 #define MMS114_X_RESOLUTION             0x03
  27 #define MMS114_Y_RESOLUTION             0x04
  28 #define MMS114_CONTACT_THRESHOLD        0x05
  29 #define MMS114_MOVING_THRESHOLD         0x06
  30
  31 /* Read only registers */
  32 #define MMS114_PACKET_SIZE              0x0F
  33 #define MMS114_INFOMATION               0x10
  34 #define MMS114_TSP_REV                  0xF0
  35
  36 /* Minimum delay time is 50us between stop and start signal of i2c */
  37 #define MMS114_I2C_DELAY                50
  38
  39 /* 200ms needs after power on */
  40 #define MMS114_POWERON_DELAY            200
  41
  42 /* Touchscreen absolute values */
  43 #define MMS114_MAX_AREA                 0xff
  44
  45 #define MMS114_MAX_TOUCH                10
  46 #define MMS114_PACKET_NUM               8
  47
  48 /* Touch type */
  49 #define MMS114_TYPE_NONE                0
  50 #define MMS114_TYPE_TOUCHSCREEN         1
  51 #define MMS114_TYPE_TOUCHKEY            2
  52
  53 struct mms114_data {
  54         struct i2c_client       *client;
  55         struct input_dev        *input_dev;
  56         struct regulator        *core_reg;
  57         struct regulator        *io_reg;
  58         const struct mms114_platform_data       *pdata;
  59
  60         /* Use cache data for mode control register(write only) */
  61         u8                      cache_mode_control;
  62 };
  63
  64 struct mms114_touch {
  65         u8 id:4, reserved_bit4:1, type:2, pressed:1;
  66         u8 x_hi:4, y_hi:4;
  67         u8 x_lo;
  68         u8 y_lo;
  69         u8 width;
  70         u8 strength;
  71         u8 reserved[2];
  72 } __packed;
  73
  74 static int __mms114_read_reg(struct mms114_data *data, unsigned int reg,
  75                              unsigned int len, u8 *val)
  76 {
  77         struct i2c_client *client = data->client;
  78         struct i2c_msg xfer[2];
  79         u8 buf = reg & 0xff;
  80         int error;
  81
  82         if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL)
  83                 BUG();
  84
  85         /* Write register: use repeated start */
  86         xfer[0].addr = client->addr;
  87         xfer[0].flags = I2C_M_TEN | I2C_M_NOSTART;
  88         xfer[0].len = 1;
  89         xfer[0].buf = &buf;
  90
  91         /* Read data */
  92         xfer[1].addr = client->addr;
  93         xfer[1].flags = I2C_M_RD;
  94         xfer[1].len = len;
  95         xfer[1].buf = val;
  96
  97         error = i2c_transfer(client->adapter, xfer, 2);
  98         if (error != 2) {
  99                 dev_err(&client->dev,
 100                         "%s: i2c transfer failed (%d)\n", __func__, error);
 101                 return error < 0 ? error : -EIO;
 102         }
 103         udelay(MMS114_I2C_DELAY);
 104
 105         return 0;
 106 }
 107
 108 static int mms114_read_reg(struct mms114_data *data, unsigned int reg)
 109 {
 110         u8 val;
 111         int error;
 112
 113         if (reg == MMS114_MODE_CONTROL)
 114                 return data->cache_mode_control;
 115
 116         error = __mms114_read_reg(data, reg, 1, &val);
 117         return error < 0 ? error : val;
 118 }
 119
 120 static int mms114_write_reg(struct mms114_data *data, unsigned int reg,
 121                             unsigned int val)
 122 {
 123         struct i2c_client *client = data->client;
 124         u8 buf[2];
 125         int error;
 126
 127         buf[0] = reg & 0xff;
 128         buf[1] = val & 0xff;
 129
 130         error = i2c_master_send(client, buf, 2);
 131         if (error != 2) {
 132                 dev_err(&client->dev,
 133                         "%s: i2c send failed (%d)\n", __func__, error);
 134                 return error < 0 ? error : -EIO;
 135         }
 136         udelay(MMS114_I2C_DELAY);
 137
 138         if (reg == MMS114_MODE_CONTROL)
 139                 data->cache_mode_control = val;
 140
 141         return 0;
 142 }
 143
 144 static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch)
 145 {
 146         const struct mms114_platform_data *pdata = data->pdata;
 147         struct i2c_client *client = data->client;
 148         struct input_dev *input_dev = data->input_dev;
 149         unsigned int id;
 150         unsigned int x;
 151         unsigned int y;
 152
 153         if (touch->id > MMS114_MAX_TOUCH) {
 154                 dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id);
 155                 return;
 156         }
 157
 158         if (touch->type != MMS114_TYPE_TOUCHSCREEN) {
 159                 dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type);
 160                 return;
 161         }
 162
 163         id = touch->id - 1;
 164         x = touch->x_lo | touch->x_hi << 8;
 165         y = touch->y_lo | touch->y_hi << 8;
 166         if (x > pdata->x_size || y > pdata->y_size) {
 167                 dev_dbg(&client->dev,
 168                         "Wrong touch coordinates (%d, %d)\n", x, y);
 169                 return;
 170         }
 171
 172         if (pdata->x_invert)
 173                 x = pdata->x_size - x;
 174         if (pdata->y_invert)
 175                 y = pdata->y_size - y;
 176
 177         dev_dbg(&client->dev,
 178                 "id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n",
 179                 id, touch->type, touch->pressed,
 180                 x, y, touch->width, touch->strength);
 181
 182         input_mt_slot(input_dev, id);
 183         input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed);
 184
 185         if (touch->pressed) {
 186                 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width);
 187                 input_report_abs(input_dev, ABS_MT_POSITION_X, x);
 188                 input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
 189                 input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength);
 190         }
 191 }
 192
 193 static irqreturn_t mms114_interrupt(int irq, void *dev_id)
 194 {
 195         struct mms114_data *data = dev_id;
 196         struct input_dev *input_dev = data->input_dev;
 197         struct mms114_touch touch[MMS114_MAX_TOUCH];
 198         int packet_size;
 199         int touch_size;
 200         int index;
 201         int error;
 202
 203         mutex_lock(&input_dev->mutex);
 204         if (!input_dev->users) {
 205                 mutex_unlock(&input_dev->mutex);
 206                 goto out;
 207         }
 208         mutex_unlock(&input_dev->mutex);
 209
 210         packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE);
 211         if (packet_size <= 0)
 212                 goto out;
 213
 214         touch_size = packet_size / MMS114_PACKET_NUM;
 215
 216         error = __mms114_read_reg(data, MMS114_INFOMATION, packet_size,
 217                         (u8 *)touch);
 218         if (error < 0)
 219                 goto out;
 220
 221         for (index = 0; index < touch_size; index++)
 222                 mms114_process_mt(data, touch + index);
 223
 224         input_mt_report_pointer_emulation(data->input_dev, true);
 225         input_sync(data->input_dev);
 226
 227 out:
 228         return IRQ_HANDLED;
 229 }
 230
 231 static int mms114_set_active(struct mms114_data *data, bool active)
 232 {
 233         int val;
 234
 235         val = mms114_read_reg(data, MMS114_MODE_CONTROL);
 236         if (val < 0)
 237                 return val;
 238
 239         val &= ~MMS114_OPERATION_MODE_MASK;
 240
 241         /* If active is false, sleep mode */
 242         if (active)
 243                 val |= MMS114_ACTIVE;
 244
 245         return mms114_write_reg(data, MMS114_MODE_CONTROL, val);
 246 }
 247
 248 static int mms114_get_version(struct mms114_data *data)
 249 {
 250         struct device *dev = &data->client->dev;
 251         u8 buf[6];
 252         int error;
 253
 254         error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf);
 255         if (error < 0)
 256                 return error;
 257
 258         dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n",
 259                  buf[0], buf[1], buf[3]);
 260
 261         return 0;
 262 }
 263
 264 static int mms114_setup_regs(struct mms114_data *data)
 265 {
 266         const struct mms114_platform_data *pdata = data->pdata;
 267         int val;
 268         int error;
 269
 270         error = mms114_get_version(data);
 271         if (error < 0)
 272                 return error;
 273
 274         error = mms114_set_active(data, true);
 275         if (error < 0)
 276                 return error;
 277
 278         val = (pdata->x_size >> 8) & 0xf;
 279         val |= ((pdata->y_size >> 8) & 0xf) << 4;
 280         error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val);
 281         if (error < 0)
 282                 return error;
 283
 284         val = pdata->x_size & 0xff;
 285         error = mms114_write_reg(data, MMS114_X_RESOLUTION, val);
 286         if (error < 0)
 287                 return error;
 288
 289         val = pdata->y_size & 0xff;
 290         error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val);
 291         if (error < 0)
 292                 return error;
 293
 294         if (pdata->contact_threshold) {
 295                 error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD,
 296                                 pdata->contact_threshold);
 297                 if (error < 0)
 298                         return error;
 299         }
 300
 301         if (pdata->moving_threshold) {
 302                 error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD,
 303                                 pdata->moving_threshold);
 304                 if (error < 0)
 305                         return error;
 306         }
 307
 308         return 0;
 309 }
 310
 311 static int mms114_start(struct mms114_data *data)
 312 {
 313         struct i2c_client *client = data->client;
 314         int error;
 315
 316         error = regulator_enable(data->core_reg);
 317         if (error) {
 318                 dev_err(&client->dev, "Failed to enable avdd: %d\n", error);
 319                 return error;
 320         }
 321
 322         error = regulator_enable(data->io_reg);
 323         if (error) {
 324                 dev_err(&client->dev, "Failed to enable vdd: %d\n", error);
 325                 regulator_disable(data->core_reg);
 326                 return error;
 327         }
 328
 329         mdelay(MMS114_POWERON_DELAY);
 330
 331         error = mms114_setup_regs(data);
 332         if (error < 0) {
 333                 regulator_disable(data->io_reg);
 334                 regulator_disable(data->core_reg);
 335                 return error;
 336         }
 337
 338         if (data->pdata->cfg_pin)
 339                 data->pdata->cfg_pin(true);
 340
 341         enable_irq(client->irq);
 342
 343         return 0;
 344 }
 345
 346 static void mms114_stop(struct mms114_data *data)
 347 {
 348         struct i2c_client *client = data->client;
 349         int error;
 350
 351         disable_irq(client->irq);
 352
 353         if (data->pdata->cfg_pin)
 354                 data->pdata->cfg_pin(false);
 355
 356         error = regulator_disable(data->io_reg);
 357         if (error)
 358                 dev_warn(&client->dev, "Failed to disable vdd: %d\n", error);
 359
 360         error = regulator_disable(data->core_reg);
 361         if (error)
 362                 dev_warn(&client->dev, "Failed to disable avdd: %d\n", error);
 363 }
 364
 365 static int mms114_input_open(struct input_dev *dev)
 366 {
 367         struct mms114_data *data = input_get_drvdata(dev);
 368
 369         return mms114_start(data);
 370 }
 371
 372 static void mms114_input_close(struct input_dev *dev)
 373 {
 374         struct mms114_data *data = input_get_drvdata(dev);
 375
 376         mms114_stop(data);
 377 }
 378
 379 #ifdef CONFIG_OF
 380 static struct mms114_platform_data *mms114_parse_dt(struct device *dev)
 381 {
 382         struct mms114_platform_data *pdata;
 383         struct device_node *np = dev->of_node;
 384
 385         if (!np)
 386                 return NULL;
 387
 388         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 389         if (!pdata) {
 390                 dev_err(dev, "failed to allocate platform data\n");
 391                 return NULL;
 392         }
 393
 394         if (of_property_read_u32(np, "x-size", &pdata->x_size)) {
 395                 dev_err(dev, "failed to get x-size property\n");
 396                 return NULL;
 397         };
 398
 399         if (of_property_read_u32(np, "y-size", &pdata->y_size)) {
 400                 dev_err(dev, "failed to get y-size property\n");
 401                 return NULL;
 402         };
 403
 404         of_property_read_u32(np, "contact-threshold",
 405                                 &pdata->contact_threshold);
 406         of_property_read_u32(np, "moving-threshold",
 407                                 &pdata->moving_threshold);
 408
 409         if (of_find_property(np, "x-invert", NULL))
 410                 pdata->x_invert = true;
 411         if (of_find_property(np, "y-invert", NULL))
 412                 pdata->y_invert = true;
 413
 414         return pdata;
 415 }
 416 #else
 417 static inline struct mms114_platform_data *mms114_parse_dt(struct device *dev)
 418 {
 419         return NULL;
 420 }
 421 #endif
 422
 423 static int mms114_probe(struct i2c_client *client,
 424                                   const struct i2c_device_id *id)
 425 {
 426         const struct mms114_platform_data *pdata;
 427         struct mms114_data *data;
 428         struct input_dev *input_dev;
 429         int error;
 430
 431         pdata = dev_get_platdata(&client->dev);
 432         if (!pdata)
 433                 pdata = mms114_parse_dt(&client->dev);
 434
 435         if (!pdata) {
 436                 dev_err(&client->dev, "Need platform data\n");
 437                 return -EINVAL;
 438         }
 439
 440         if (!i2c_check_functionality(client->adapter,
 441                                 I2C_FUNC_PROTOCOL_MANGLING)) {
 442                 dev_err(&client->dev,
 443                         "Need i2c bus that supports protocol mangling\n");
 444                 return -ENODEV;
 445         }
 446
 447         data = devm_kzalloc(&client->dev, sizeof(struct mms114_data),
 448                             GFP_KERNEL);
 449         input_dev = devm_input_allocate_device(&client->dev);
 450         if (!data || !input_dev) {
 451                 dev_err(&client->dev, "Failed to allocate memory\n");
 452                 return -ENOMEM;
 453         }
 454
 455         data->client = client;
 456         data->input_dev = input_dev;
 457         data->pdata = pdata;
 458
 459         input_dev->name = "MELFAS MMS114 Touchscreen";
 460         input_dev->id.bustype = BUS_I2C;
 461         input_dev->dev.parent = &client->dev;
 462         input_dev->open = mms114_input_open;
 463         input_dev->close = mms114_input_close;
 464
 465         __set_bit(EV_ABS, input_dev->evbit);
 466         __set_bit(EV_KEY, input_dev->evbit);
 467         __set_bit(BTN_TOUCH, input_dev->keybit);
 468         input_set_abs_params(input_dev, ABS_X, 0, data->pdata->x_size, 0, 0);
 469         input_set_abs_params(input_dev, ABS_Y, 0, data->pdata->y_size, 0, 0);
 470
 471         /* For multi touch */
 472         input_mt_init_slots(input_dev, MMS114_MAX_TOUCH, 0);
 473         input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 474                              0, MMS114_MAX_AREA, 0, 0);
 475         input_set_abs_params(input_dev, ABS_MT_POSITION_X,
 476                              0, data->pdata->x_size, 0, 0);
 477         input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
 478                              0, data->pdata->y_size, 0, 0);
 479         input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
 480
 481         input_set_drvdata(input_dev, data);
 482         i2c_set_clientdata(client, data);
 483
 484         data->core_reg = devm_regulator_get(&client->dev, "avdd");
 485         if (IS_ERR(data->core_reg)) {
 486                 error = PTR_ERR(data->core_reg);
 487                 dev_err(&client->dev,
 488                         "Unable to get the Core regulator (%d)\n", error);
 489                 return error;
 490         }
 491
 492         data->io_reg = devm_regulator_get(&client->dev, "vdd");
 493         if (IS_ERR(data->io_reg)) {
 494                 error = PTR_ERR(data->io_reg);
 495                 dev_err(&client->dev,
 496                         "Unable to get the IO regulator (%d)\n", error);
 497                 return error;
 498         }
 499
 500         error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
 501                         mms114_interrupt, IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 502                         dev_name(&client->dev), data);
 503         if (error) {
 504                 dev_err(&client->dev, "Failed to register interrupt\n");
 505                 return error;
 506         }
 507         disable_irq(client->irq);
 508
 509         error = input_register_device(data->input_dev);
 510         if (error) {
 511                 dev_err(&client->dev, "Failed to register input device\n");
 512                 return error;
 513         }
 514
 515         return 0;
 516 }
 517
 518 static int __maybe_unused mms114_suspend(struct device *dev)
 519 {
 520         struct i2c_client *client = to_i2c_client(dev);
 521         struct mms114_data *data = i2c_get_clientdata(client);
 522         struct input_dev *input_dev = data->input_dev;
 523         int id;
 524
 525         /* Release all touch */
 526         for (id = 0; id < MMS114_MAX_TOUCH; id++) {
 527                 input_mt_slot(input_dev, id);
 528                 input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false);
 529         }
 530
 531         input_mt_report_pointer_emulation(input_dev, true);
 532         input_sync(input_dev);
 533
 534         mutex_lock(&input_dev->mutex);
 535         if (input_dev->users)
 536                 mms114_stop(data);
 537         mutex_unlock(&input_dev->mutex);
 538
 539         return 0;
 540 }
 541
 542 static int __maybe_unused mms114_resume(struct device *dev)
 543 {
 544         struct i2c_client *client = to_i2c_client(dev);
 545         struct mms114_data *data = i2c_get_clientdata(client);
 546         struct input_dev *input_dev = data->input_dev;
 547         int error;
 548
 549         mutex_lock(&input_dev->mutex);
 550         if (input_dev->users) {
 551                 error = mms114_start(data);
 552                 if (error < 0) {
 553                         mutex_unlock(&input_dev->mutex);
 554                         return error;
 555                 }
 556         }
 557         mutex_unlock(&input_dev->mutex);
 558
 559         return 0;
 560 }
 561
 562 static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume);
 563
 564 static const struct i2c_device_id mms114_id[] = {
 565         { "mms114", 0 },
 566         { }
 567 };
 568 MODULE_DEVICE_TABLE(i2c, mms114_id);
 569
 570 #ifdef CONFIG_OF
 571 static const struct of_device_id mms114_dt_match[] = {
 572         { .compatible = "melfas,mms114" },
 573         { }
 574 };
 575 #endif
 576
 577 static struct i2c_driver mms114_driver = {
 578         .driver = {
 579                 .name   = "mms114",
 580                 .owner  = THIS_MODULE,
 581                 .pm     = &mms114_pm_ops,
 582                 .of_match_table = of_match_ptr(mms114_dt_match),
 583         },
 584         .probe          = mms114_probe,
 585         .id_table       = mms114_id,
 586 };
 587
 588 module_i2c_driver(mms114_driver);
 589
 590 /* Module information */
 591 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
 592 MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver");
 593 MODULE_LICENSE("GPL");