drivers/iio/temperature/tmp007.c

   1 /*
   2  * tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
   3  *
   4  * Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
   5  *
   6  * This file is subject to the terms and conditions of version 2 of
   7  * the GNU General Public License.  See the file COPYING in the main
   8  * directory of this archive for more details.
   9  *
  10  * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
  11  *
  12  * (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
  13  *
  14  * Note:
  15  * 1. This driver assumes that the sensor has been calibrated beforehand
  16  * 2. Limit threshold events are enabled at the start
  17  * 3. Operating mode: INT
  18  *
  19  */
  20
  21 #include <linux/err.h>
  22 #include <linux/i2c.h>
  23 #include <linux/delay.h>
  24 #include <linux/module.h>
  25 #include <linux/pm.h>
  26 #include <linux/bitops.h>
  27 #include <linux/of.h>
  28 #include <linux/irq.h>
  29 #include <linux/interrupt.h>
  30
  31 #include <linux/iio/iio.h>
  32 #include <linux/iio/sysfs.h>
  33 #include <linux/iio/events.h>
  34
  35 #define TMP007_TDIE 0x01
  36 #define TMP007_CONFIG 0x02
  37 #define TMP007_TOBJECT 0x03
  38 #define TMP007_STATUS 0x04
  39 #define TMP007_STATUS_MASK 0x05
  40 #define TMP007_TOBJ_HIGH_LIMIT 0x06
  41 #define TMP007_TOBJ_LOW_LIMIT 0x07
  42 #define TMP007_TDIE_HIGH_LIMIT 0x08
  43 #define TMP007_TDIE_LOW_LIMIT 0x09
  44 #define TMP007_MANUFACTURER_ID 0x1e
  45 #define TMP007_DEVICE_ID 0x1f
  46
  47 #define TMP007_CONFIG_CONV_EN BIT(12)
  48 #define TMP007_CONFIG_TC_EN BIT(6)
  49 #define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
  50 #define TMP007_CONFIG_ALERT_EN BIT(8)
  51 #define TMP007_CONFIG_CR_SHIFT 9
  52
  53 /* Status register flags */
  54 #define TMP007_STATUS_ALERT BIT(15)
  55 #define TMP007_STATUS_CONV_READY BIT(14)
  56 #define TMP007_STATUS_OHF BIT(13)
  57 #define TMP007_STATUS_OLF BIT(12)
  58 #define TMP007_STATUS_LHF BIT(11)
  59 #define TMP007_STATUS_LLF BIT(10)
  60 #define TMP007_STATUS_DATA_VALID BIT(9)
  61
  62 #define TMP007_MANUFACTURER_MAGIC 0x5449
  63 #define TMP007_DEVICE_MAGIC 0x0078
  64
  65 #define TMP007_TEMP_SHIFT 2
  66
  67 struct tmp007_data {
  68         struct i2c_client *client;
  69         struct mutex lock;
  70         u16 config;
  71         u16 status_mask;
  72 };
  73
  74 static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
  75                                         {0, 500000}, {0, 250000} };
  76
  77 static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
  78 {
  79         s32 ret;
  80         int tries = 50;
  81
  82         while (tries-- > 0) {
  83                 ret = i2c_smbus_read_word_swapped(data->client,
  84                         TMP007_STATUS);
  85                 if (ret < 0)
  86                         return ret;
  87                 if ((ret & TMP007_STATUS_CONV_READY) &&
  88                         !(ret & TMP007_STATUS_DATA_VALID))
  89                                 break;
  90                 msleep(100);
  91         }
  92
  93         if (tries < 0)
  94                 return -EIO;
  95
  96         return i2c_smbus_read_word_swapped(data->client, reg);
  97 }
  98
  99 static int tmp007_powerdown(struct tmp007_data *data)
 100 {
 101         return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 102                         data->config & ~TMP007_CONFIG_CONV_EN);
 103 }
 104
 105 static int tmp007_read_raw(struct iio_dev *indio_dev,
 106                 struct iio_chan_spec const *channel, int *val,
 107                 int *val2, long mask)
 108 {
 109         struct tmp007_data *data = iio_priv(indio_dev);
 110         s32 ret;
 111         int conv_rate;
 112
 113         switch (mask) {
 114         case IIO_CHAN_INFO_RAW:
 115                 switch (channel->channel2) {
 116                 case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
 117                         ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
 118                         if (ret < 0)
 119                                 return ret;
 120                         break;
 121                 case IIO_MOD_TEMP_OBJECT:
 122                         ret = tmp007_read_temperature(data, TMP007_TOBJECT);
 123                         if (ret < 0)
 124                                 return ret;
 125                         break;
 126                 default:
 127                         return -EINVAL;
 128                 }
 129
 130                 *val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;
 131
 132                 return IIO_VAL_INT;
 133         case IIO_CHAN_INFO_SCALE:
 134                 *val = 31;
 135                 *val2 = 250000;
 136
 137                 return IIO_VAL_INT_PLUS_MICRO;
 138         case IIO_CHAN_INFO_SAMP_FREQ:
 139                 conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
 140                                 >> TMP007_CONFIG_CR_SHIFT;
 141                 *val = tmp007_avgs[conv_rate][0];
 142                 *val2 = tmp007_avgs[conv_rate][1];
 143
 144                 return IIO_VAL_INT_PLUS_MICRO;
 145         default:
 146                 return -EINVAL;
 147         }
 148 }
 149
 150 static int tmp007_write_raw(struct iio_dev *indio_dev,
 151                 struct iio_chan_spec const *channel, int val,
 152                 int val2, long mask)
 153 {
 154         struct tmp007_data *data = iio_priv(indio_dev);
 155         int i;
 156         u16 tmp;
 157
 158         if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
 159                 for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
 160                         if ((val == tmp007_avgs[i][0]) &&
 161                         (val2 == tmp007_avgs[i][1])) {
 162                                 tmp = data->config & ~TMP007_CONFIG_CR_MASK;
 163                                 tmp |= (i << TMP007_CONFIG_CR_SHIFT);
 164
 165                                 return i2c_smbus_write_word_swapped(data->client,
 166                                                                 TMP007_CONFIG,
 167                                                                 data->config = tmp);
 168                         }
 169                 }
 170         }
 171
 172         return -EINVAL;
 173 }
 174
 175 static irqreturn_t tmp007_interrupt_handler(int irq, void *private)
 176 {
 177         struct iio_dev *indio_dev = private;
 178         struct tmp007_data *data = iio_priv(indio_dev);
 179         int ret;
 180
 181         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS);
 182         if ((ret < 0) || !(ret & (TMP007_STATUS_OHF | TMP007_STATUS_OLF |
 183                                 TMP007_STATUS_LHF | TMP007_STATUS_LLF)))
 184                 return IRQ_NONE;
 185
 186         if (ret & TMP007_STATUS_OHF)
 187                 iio_push_event(indio_dev,
 188                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 189                                         IIO_MOD_TEMP_OBJECT,
 190                                         IIO_EV_TYPE_THRESH,
 191                                         IIO_EV_DIR_RISING),
 192                                 iio_get_time_ns(indio_dev));
 193
 194         if (ret & TMP007_STATUS_OLF)
 195                 iio_push_event(indio_dev,
 196                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 197                                         IIO_MOD_TEMP_OBJECT,
 198                                         IIO_EV_TYPE_THRESH,
 199                                         IIO_EV_DIR_FALLING),
 200                                 iio_get_time_ns(indio_dev));
 201
 202         if (ret & TMP007_STATUS_LHF)
 203                 iio_push_event(indio_dev,
 204                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 205                                         IIO_MOD_TEMP_AMBIENT,
 206                                         IIO_EV_TYPE_THRESH,
 207                                         IIO_EV_DIR_RISING),
 208                                 iio_get_time_ns(indio_dev));
 209
 210         if (ret & TMP007_STATUS_LLF)
 211                 iio_push_event(indio_dev,
 212                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 213                                         IIO_MOD_TEMP_AMBIENT,
 214                                         IIO_EV_TYPE_THRESH,
 215                                         IIO_EV_DIR_FALLING),
 216                                 iio_get_time_ns(indio_dev));
 217
 218         return IRQ_HANDLED;
 219 }
 220
 221 static int tmp007_write_event_config(struct iio_dev *indio_dev,
 222                 const struct iio_chan_spec *chan, enum iio_event_type type,
 223                 enum iio_event_direction dir, int state)
 224 {
 225         struct tmp007_data *data = iio_priv(indio_dev);
 226         unsigned int status_mask;
 227         int ret;
 228
 229         switch (chan->channel2) {
 230         case IIO_MOD_TEMP_AMBIENT:
 231         if (dir == IIO_EV_DIR_RISING)
 232                         status_mask = TMP007_STATUS_LHF;
 233                 else
 234                         status_mask = TMP007_STATUS_LLF;
 235                 break;
 236         case IIO_MOD_TEMP_OBJECT:
 237                 if (dir == IIO_EV_DIR_RISING)
 238                         status_mask = TMP007_STATUS_OHF;
 239                 else
 240                         status_mask = TMP007_STATUS_OLF;
 241                 break;
 242         default:
 243                 return -EINVAL;
 244         }
 245
 246         mutex_lock(&data->lock);
 247         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 248         mutex_unlock(&data->lock);
 249         if (ret < 0)
 250                 return ret;
 251
 252         if (state)
 253                 ret |= status_mask;
 254         else
 255                 ret &= ~status_mask;
 256
 257         return i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK,
 258                                         data->status_mask = ret);
 259 }
 260
 261 static int tmp007_read_event_config(struct iio_dev *indio_dev,
 262                 const struct iio_chan_spec *chan, enum iio_event_type type,
 263                 enum iio_event_direction dir)
 264 {
 265         struct tmp007_data *data = iio_priv(indio_dev);
 266         unsigned int mask;
 267
 268         switch (chan->channel2) {
 269         case IIO_MOD_TEMP_AMBIENT:
 270                 if (dir == IIO_EV_DIR_RISING)
 271                         mask = TMP007_STATUS_LHF;
 272                 else
 273                         mask = TMP007_STATUS_LLF;
 274                 break;
 275         case IIO_MOD_TEMP_OBJECT:
 276                 if (dir == IIO_EV_DIR_RISING)
 277                         mask = TMP007_STATUS_OHF;
 278                 else
 279                         mask = TMP007_STATUS_OLF;
 280                 break;
 281         default:
 282                 return -EINVAL;
 283         }
 284
 285         return !!(data->status_mask & mask);
 286 }
 287
 288 static int tmp007_read_thresh(struct iio_dev *indio_dev,
 289                 const struct iio_chan_spec *chan, enum iio_event_type type,
 290                 enum iio_event_direction dir, enum iio_event_info info,
 291                 int *val, int *val2)
 292 {
 293         struct tmp007_data *data = iio_priv(indio_dev);
 294         int ret;
 295         u8 reg;
 296
 297         switch (chan->channel2) {
 298         case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.5 degree Celsius */
 299                 if (dir == IIO_EV_DIR_RISING)
 300                         reg = TMP007_TDIE_HIGH_LIMIT;
 301                 else
 302                         reg = TMP007_TDIE_LOW_LIMIT;
 303                 break;
 304         case IIO_MOD_TEMP_OBJECT:
 305                 if (dir == IIO_EV_DIR_RISING)
 306                         reg = TMP007_TOBJ_HIGH_LIMIT;
 307         else
 308                         reg = TMP007_TOBJ_LOW_LIMIT;
 309                 break;
 310         default:
 311                 return -EINVAL;
 312         }
 313
 314         ret = i2c_smbus_read_word_swapped(data->client, reg);
 315         if (ret < 0)
 316                 return ret;
 317
 318         /* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 319         *val = sign_extend32(ret, 15) >> 7;
 320
 321         return IIO_VAL_INT;
 322 }
 323
 324 static int tmp007_write_thresh(struct iio_dev *indio_dev,
 325                 const struct iio_chan_spec *chan, enum iio_event_type type,
 326                 enum iio_event_direction dir, enum iio_event_info info,
 327                 int val, int val2)
 328 {
 329         struct tmp007_data *data = iio_priv(indio_dev);
 330         u8 reg;
 331
 332         switch (chan->channel2) {
 333         case IIO_MOD_TEMP_AMBIENT:
 334                 if (dir == IIO_EV_DIR_RISING)
 335                         reg = TMP007_TDIE_HIGH_LIMIT;
 336                 else
 337                         reg = TMP007_TDIE_LOW_LIMIT;
 338                 break;
 339         case IIO_MOD_TEMP_OBJECT:
 340                 if (dir == IIO_EV_DIR_RISING)
 341                         reg = TMP007_TOBJ_HIGH_LIMIT;
 342                 else
 343                         reg = TMP007_TOBJ_LOW_LIMIT;
 344                 break;
 345         default:
 346                 return -EINVAL;
 347         }
 348
 349         /* Full scale threshold value is +/- 256 degree Celsius */
 350         if (val < -256 || val > 255)
 351                 return -EINVAL;
 352
 353         /* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 354         return i2c_smbus_write_word_swapped(data->client, reg, (val << 7));
 355 }
 356
 357 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
 358
 359 static struct attribute *tmp007_attributes[] = {
 360         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 361         NULL
 362 };
 363
 364 static const struct attribute_group tmp007_attribute_group = {
 365         .attrs = tmp007_attributes,
 366 };
 367
 368 static const struct iio_event_spec tmp007_obj_event[] = {
 369         {
 370                 .type = IIO_EV_TYPE_THRESH,
 371                 .dir = IIO_EV_DIR_RISING,
 372                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 373                         BIT(IIO_EV_INFO_ENABLE),
 374         },
 375         {
 376                 .type = IIO_EV_TYPE_THRESH,
 377                 .dir = IIO_EV_DIR_FALLING,
 378                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 379                         BIT(IIO_EV_INFO_ENABLE),
 380         },
 381 };
 382
 383 static const struct iio_event_spec tmp007_die_event[] = {
 384         {
 385                 .type = IIO_EV_TYPE_THRESH,
 386                 .dir = IIO_EV_DIR_RISING,
 387                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 388                         BIT(IIO_EV_INFO_ENABLE),
 389         },
 390         {
 391                 .type = IIO_EV_TYPE_THRESH,
 392                 .dir = IIO_EV_DIR_FALLING,
 393                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 394                         BIT(IIO_EV_INFO_ENABLE),
 395         },
 396 };
 397
 398 static const struct iio_chan_spec tmp007_channels[] = {
 399         {
 400                 .type = IIO_TEMP,
 401                 .modified = 1,
 402                 .channel2 = IIO_MOD_TEMP_AMBIENT,
 403                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 404                                 BIT(IIO_CHAN_INFO_SCALE),
 405                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 406                 .event_spec = tmp007_die_event,
 407                 .num_event_specs = ARRAY_SIZE(tmp007_die_event),
 408         },
 409         {
 410                 .type = IIO_TEMP,
 411                 .modified = 1,
 412                 .channel2 = IIO_MOD_TEMP_OBJECT,
 413                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 414                                 BIT(IIO_CHAN_INFO_SCALE),
 415                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 416                 .event_spec = tmp007_obj_event,
 417                 .num_event_specs = ARRAY_SIZE(tmp007_obj_event),
 418         }
 419 };
 420
 421 static const struct iio_info tmp007_info = {
 422         .read_raw = tmp007_read_raw,
 423         .write_raw = tmp007_write_raw,
 424         .read_event_config = tmp007_read_event_config,
 425         .write_event_config = tmp007_write_event_config,
 426         .read_event_value = tmp007_read_thresh,
 427         .write_event_value = tmp007_write_thresh,
 428         .attrs = &tmp007_attribute_group,
 429 };
 430
 431 static bool tmp007_identify(struct i2c_client *client)
 432 {
 433         int manf_id, dev_id;
 434
 435         manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
 436         if (manf_id < 0)
 437                 return false;
 438
 439         dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
 440         if (dev_id < 0)
 441                 return false;
 442
 443         return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
 444 }
 445
 446 static int tmp007_probe(struct i2c_client *client,
 447                         const struct i2c_device_id *tmp007_id)
 448 {
 449         struct tmp007_data *data;
 450         struct iio_dev *indio_dev;
 451         int ret;
 452
 453         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 454                 return -EOPNOTSUPP;
 455
 456         if (!tmp007_identify(client)) {
 457                 dev_err(&client->dev, "TMP007 not found\n");
 458                 return -ENODEV;
 459         }
 460
 461         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 462         if (!indio_dev)
 463                 return -ENOMEM;
 464
 465         data = iio_priv(indio_dev);
 466         i2c_set_clientdata(client, indio_dev);
 467         data->client = client;
 468         mutex_init(&data->lock);
 469
 470         indio_dev->dev.parent = &client->dev;
 471         indio_dev->name = "tmp007";
 472         indio_dev->modes = INDIO_DIRECT_MODE;
 473         indio_dev->info = &tmp007_info;
 474
 475         indio_dev->channels = tmp007_channels;
 476         indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);
 477
 478         /*
 479          * Set Configuration register:
 480          * 1. Conversion ON
 481          * 2. ALERT enable
 482          * 3. Transient correction enable
 483          */
 484
 485         ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
 486         if (ret < 0)
 487                 return ret;
 488
 489         data->config = ret;
 490         data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_ALERT_EN | TMP007_CONFIG_TC_EN);
 491
 492         ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 493                                         data->config);
 494         if (ret < 0)
 495                 return ret;
 496
 497         /*
 498          * Only the following flags can activate ALERT pin. Data conversion/validity flags
 499          * flags can still be polled for getting temperature data
 500          *
 501          * Set Status Mask register:
 502          * 1. Object temperature high limit enable
 503          * 2. Object temperature low limit enable
 504          * 3. TDIE temperature high limit enable
 505          * 4. TDIE temperature low limit enable
 506          */
 507
 508         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 509         if (ret < 0)
 510                 goto error_powerdown;
 511
 512         data->status_mask = ret;
 513         data->status_mask |= (TMP007_STATUS_OHF | TMP007_STATUS_OLF
 514                                 | TMP007_STATUS_LHF | TMP007_STATUS_LLF);
 515
 516         ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
 517         if (ret < 0)
 518                 goto error_powerdown;
 519
 520         if (client->irq) {
 521                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 522                                 NULL, tmp007_interrupt_handler,
 523                                 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 524                                 tmp007_id->name, indio_dev);
 525                 if (ret) {
 526                         dev_err(&client->dev, "irq request error %d\n", -ret);
 527                         goto error_powerdown;
 528                 }
 529         }
 530
 531         return iio_device_register(indio_dev);
 532
 533 error_powerdown:
 534         tmp007_powerdown(data);
 535
 536         return ret;
 537 }
 538
 539 static int tmp007_remove(struct i2c_client *client)
 540 {
 541         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 542         struct tmp007_data *data = iio_priv(indio_dev);
 543
 544         iio_device_unregister(indio_dev);
 545         tmp007_powerdown(data);
 546
 547         return 0;
 548 }
 549
 550 #ifdef CONFIG_PM_SLEEP
 551 static int tmp007_suspend(struct device *dev)
 552 {
 553         struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 554                         to_i2c_client(dev)));
 555
 556         return tmp007_powerdown(data);
 557 }
 558
 559 static int tmp007_resume(struct device *dev)
 560 {
 561         struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 562                         to_i2c_client(dev)));
 563
 564         return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 565                         data->config | TMP007_CONFIG_CONV_EN);
 566 }
 567 #endif
 568
 569 static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
 570
 571 static const struct of_device_id tmp007_of_match[] = {
 572         { .compatible = "ti,tmp007", },
 573         { },
 574 };
 575 MODULE_DEVICE_TABLE(of, tmp007_of_match);
 576
 577 static const struct i2c_device_id tmp007_id[] = {
 578         { "tmp007", 0 },
 579         { }
 580 };
 581 MODULE_DEVICE_TABLE(i2c, tmp007_id);
 582
 583 static struct i2c_driver tmp007_driver = {
 584         .driver = {
 585                 .name   = "tmp007",
 586                 .of_match_table = of_match_ptr(tmp007_of_match),
 587                 .pm     = &tmp007_pm_ops,
 588         },
 589         .probe          = tmp007_probe,
 590         .remove         = tmp007_remove,
 591         .id_table       = tmp007_id,
 592 };
 593 module_i2c_driver(tmp007_driver);
 594
 595 MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
 596 MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
 597 MODULE_LICENSE("GPL");