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