drivers/iio/temperature/tmp007.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tmp007.c - Support for TI TMP007 IR thermopile sensor with integrated math engine
   4  *
   5  * Copyright (c) 2017 Manivannan Sadhasivam <manivannanece23@gmail.com>
   6  *
   7  * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
   8  *
   9  * (7-bit I2C slave address (0x40 - 0x47), changeable via ADR pins)
  10  *
  11  * Note:
  12  * 1. This driver assumes that the sensor has been calibrated beforehand
  13  * 2. Limit threshold events are enabled at the start
  14  * 3. Operating mode: INT
  15  */
  16
  17 #include <linux/err.h>
  18 #include <linux/i2c.h>
  19 #include <linux/delay.h>
  20 #include <linux/module.h>
  21 #include <linux/pm.h>
  22 #include <linux/bitops.h>
  23 #include <linux/mod_devicetable.h>
  24 #include <linux/irq.h>
  25 #include <linux/interrupt.h>
  26
  27 #include <linux/iio/iio.h>
  28 #include <linux/iio/sysfs.h>
  29 #include <linux/iio/events.h>
  30
  31 #define TMP007_TDIE 0x01
  32 #define TMP007_CONFIG 0x02
  33 #define TMP007_TOBJECT 0x03
  34 #define TMP007_STATUS 0x04
  35 #define TMP007_STATUS_MASK 0x05
  36 #define TMP007_TOBJ_HIGH_LIMIT 0x06
  37 #define TMP007_TOBJ_LOW_LIMIT 0x07
  38 #define TMP007_TDIE_HIGH_LIMIT 0x08
  39 #define TMP007_TDIE_LOW_LIMIT 0x09
  40 #define TMP007_MANUFACTURER_ID 0x1e
  41 #define TMP007_DEVICE_ID 0x1f
  42
  43 #define TMP007_CONFIG_CONV_EN BIT(12)
  44 #define TMP007_CONFIG_TC_EN BIT(6)
  45 #define TMP007_CONFIG_CR_MASK GENMASK(11, 9)
  46 #define TMP007_CONFIG_ALERT_EN BIT(8)
  47 #define TMP007_CONFIG_CR_SHIFT 9
  48
  49 /* Status register flags */
  50 #define TMP007_STATUS_ALERT BIT(15)
  51 #define TMP007_STATUS_CONV_READY BIT(14)
  52 #define TMP007_STATUS_OHF BIT(13)
  53 #define TMP007_STATUS_OLF BIT(12)
  54 #define TMP007_STATUS_LHF BIT(11)
  55 #define TMP007_STATUS_LLF BIT(10)
  56 #define TMP007_STATUS_DATA_VALID BIT(9)
  57
  58 #define TMP007_MANUFACTURER_MAGIC 0x5449
  59 #define TMP007_DEVICE_MAGIC 0x0078
  60
  61 #define TMP007_TEMP_SHIFT 2
  62
  63 struct tmp007_data {
  64         struct i2c_client *client;
  65         struct mutex lock;
  66         u16 config;
  67         u16 status_mask;
  68 };
  69
  70 static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
  71                                         {0, 500000}, {0, 250000} };
  72
  73 static int tmp007_read_temperature(struct tmp007_data *data, u8 reg)
  74 {
  75         s32 ret;
  76         int tries = 50;
  77
  78         while (tries-- > 0) {
  79                 ret = i2c_smbus_read_word_swapped(data->client,
  80                         TMP007_STATUS);
  81                 if (ret < 0)
  82                         return ret;
  83                 if ((ret & TMP007_STATUS_CONV_READY) &&
  84                         !(ret & TMP007_STATUS_DATA_VALID))
  85                                 break;
  86                 msleep(100);
  87         }
  88
  89         if (tries < 0)
  90                 return -EIO;
  91
  92         return i2c_smbus_read_word_swapped(data->client, reg);
  93 }
  94
  95 static int tmp007_powerdown(struct tmp007_data *data)
  96 {
  97         return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
  98                         data->config & ~TMP007_CONFIG_CONV_EN);
  99 }
 100
 101 static int tmp007_read_raw(struct iio_dev *indio_dev,
 102                 struct iio_chan_spec const *channel, int *val,
 103                 int *val2, long mask)
 104 {
 105         struct tmp007_data *data = iio_priv(indio_dev);
 106         s32 ret;
 107         int conv_rate;
 108
 109         switch (mask) {
 110         case IIO_CHAN_INFO_RAW:
 111                 switch (channel->channel2) {
 112                 case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.03125 degree Celsius */
 113                         ret = i2c_smbus_read_word_swapped(data->client, TMP007_TDIE);
 114                         if (ret < 0)
 115                                 return ret;
 116                         break;
 117                 case IIO_MOD_TEMP_OBJECT:
 118                         ret = tmp007_read_temperature(data, TMP007_TOBJECT);
 119                         if (ret < 0)
 120                                 return ret;
 121                         break;
 122                 default:
 123                         return -EINVAL;
 124                 }
 125
 126                 *val = sign_extend32(ret, 15) >> TMP007_TEMP_SHIFT;
 127
 128                 return IIO_VAL_INT;
 129         case IIO_CHAN_INFO_SCALE:
 130                 *val = 31;
 131                 *val2 = 250000;
 132
 133                 return IIO_VAL_INT_PLUS_MICRO;
 134         case IIO_CHAN_INFO_SAMP_FREQ:
 135                 conv_rate = (data->config & TMP007_CONFIG_CR_MASK)
 136                                 >> TMP007_CONFIG_CR_SHIFT;
 137                 *val = tmp007_avgs[conv_rate][0];
 138                 *val2 = tmp007_avgs[conv_rate][1];
 139
 140                 return IIO_VAL_INT_PLUS_MICRO;
 141         default:
 142                 return -EINVAL;
 143         }
 144 }
 145
 146 static int tmp007_write_raw(struct iio_dev *indio_dev,
 147                 struct iio_chan_spec const *channel, int val,
 148                 int val2, long mask)
 149 {
 150         struct tmp007_data *data = iio_priv(indio_dev);
 151         int i;
 152         u16 tmp;
 153
 154         if (mask == IIO_CHAN_INFO_SAMP_FREQ) {
 155                 for (i = 0; i < ARRAY_SIZE(tmp007_avgs); i++) {
 156                         if ((val == tmp007_avgs[i][0]) &&
 157                         (val2 == tmp007_avgs[i][1])) {
 158                                 tmp = data->config & ~TMP007_CONFIG_CR_MASK;
 159                                 tmp |= (i << TMP007_CONFIG_CR_SHIFT);
 160
 161                                 return i2c_smbus_write_word_swapped(data->client,
 162                                                                 TMP007_CONFIG,
 163                                                                 data->config = tmp);
 164                         }
 165                 }
 166         }
 167
 168         return -EINVAL;
 169 }
 170
 171 static irqreturn_t tmp007_interrupt_handler(int irq, void *private)
 172 {
 173         struct iio_dev *indio_dev = private;
 174         struct tmp007_data *data = iio_priv(indio_dev);
 175         int ret;
 176
 177         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS);
 178         if ((ret < 0) || !(ret & (TMP007_STATUS_OHF | TMP007_STATUS_OLF |
 179                                 TMP007_STATUS_LHF | TMP007_STATUS_LLF)))
 180                 return IRQ_NONE;
 181
 182         if (ret & TMP007_STATUS_OHF)
 183                 iio_push_event(indio_dev,
 184                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 185                                         IIO_MOD_TEMP_OBJECT,
 186                                         IIO_EV_TYPE_THRESH,
 187                                         IIO_EV_DIR_RISING),
 188                                 iio_get_time_ns(indio_dev));
 189
 190         if (ret & TMP007_STATUS_OLF)
 191                 iio_push_event(indio_dev,
 192                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 193                                         IIO_MOD_TEMP_OBJECT,
 194                                         IIO_EV_TYPE_THRESH,
 195                                         IIO_EV_DIR_FALLING),
 196                                 iio_get_time_ns(indio_dev));
 197
 198         if (ret & TMP007_STATUS_LHF)
 199                 iio_push_event(indio_dev,
 200                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 201                                         IIO_MOD_TEMP_AMBIENT,
 202                                         IIO_EV_TYPE_THRESH,
 203                                         IIO_EV_DIR_RISING),
 204                                 iio_get_time_ns(indio_dev));
 205
 206         if (ret & TMP007_STATUS_LLF)
 207                 iio_push_event(indio_dev,
 208                                 IIO_MOD_EVENT_CODE(IIO_TEMP, 0,
 209                                         IIO_MOD_TEMP_AMBIENT,
 210                                         IIO_EV_TYPE_THRESH,
 211                                         IIO_EV_DIR_FALLING),
 212                                 iio_get_time_ns(indio_dev));
 213
 214         return IRQ_HANDLED;
 215 }
 216
 217 static int tmp007_write_event_config(struct iio_dev *indio_dev,
 218                 const struct iio_chan_spec *chan, enum iio_event_type type,
 219                 enum iio_event_direction dir, int state)
 220 {
 221         struct tmp007_data *data = iio_priv(indio_dev);
 222         unsigned int status_mask;
 223         int ret;
 224
 225         switch (chan->channel2) {
 226         case IIO_MOD_TEMP_AMBIENT:
 227         if (dir == IIO_EV_DIR_RISING)
 228                         status_mask = TMP007_STATUS_LHF;
 229                 else
 230                         status_mask = TMP007_STATUS_LLF;
 231                 break;
 232         case IIO_MOD_TEMP_OBJECT:
 233                 if (dir == IIO_EV_DIR_RISING)
 234                         status_mask = TMP007_STATUS_OHF;
 235                 else
 236                         status_mask = TMP007_STATUS_OLF;
 237                 break;
 238         default:
 239                 return -EINVAL;
 240         }
 241
 242         mutex_lock(&data->lock);
 243         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 244         mutex_unlock(&data->lock);
 245         if (ret < 0)
 246                 return ret;
 247
 248         if (state)
 249                 ret |= status_mask;
 250         else
 251                 ret &= ~status_mask;
 252
 253         return i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK,
 254                                         data->status_mask = ret);
 255 }
 256
 257 static int tmp007_read_event_config(struct iio_dev *indio_dev,
 258                 const struct iio_chan_spec *chan, enum iio_event_type type,
 259                 enum iio_event_direction dir)
 260 {
 261         struct tmp007_data *data = iio_priv(indio_dev);
 262         unsigned int mask;
 263
 264         switch (chan->channel2) {
 265         case IIO_MOD_TEMP_AMBIENT:
 266                 if (dir == IIO_EV_DIR_RISING)
 267                         mask = TMP007_STATUS_LHF;
 268                 else
 269                         mask = TMP007_STATUS_LLF;
 270                 break;
 271         case IIO_MOD_TEMP_OBJECT:
 272                 if (dir == IIO_EV_DIR_RISING)
 273                         mask = TMP007_STATUS_OHF;
 274                 else
 275                         mask = TMP007_STATUS_OLF;
 276                 break;
 277         default:
 278                 return -EINVAL;
 279         }
 280
 281         return !!(data->status_mask & mask);
 282 }
 283
 284 static int tmp007_read_thresh(struct iio_dev *indio_dev,
 285                 const struct iio_chan_spec *chan, enum iio_event_type type,
 286                 enum iio_event_direction dir, enum iio_event_info info,
 287                 int *val, int *val2)
 288 {
 289         struct tmp007_data *data = iio_priv(indio_dev);
 290         int ret;
 291         u8 reg;
 292
 293         switch (chan->channel2) {
 294         case IIO_MOD_TEMP_AMBIENT: /* LSB: 0.5 degree Celsius */
 295                 if (dir == IIO_EV_DIR_RISING)
 296                         reg = TMP007_TDIE_HIGH_LIMIT;
 297                 else
 298                         reg = TMP007_TDIE_LOW_LIMIT;
 299                 break;
 300         case IIO_MOD_TEMP_OBJECT:
 301                 if (dir == IIO_EV_DIR_RISING)
 302                         reg = TMP007_TOBJ_HIGH_LIMIT;
 303         else
 304                         reg = TMP007_TOBJ_LOW_LIMIT;
 305                 break;
 306         default:
 307                 return -EINVAL;
 308         }
 309
 310         ret = i2c_smbus_read_word_swapped(data->client, reg);
 311         if (ret < 0)
 312                 return ret;
 313
 314         /* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 315         *val = sign_extend32(ret, 15) >> 7;
 316
 317         return IIO_VAL_INT;
 318 }
 319
 320 static int tmp007_write_thresh(struct iio_dev *indio_dev,
 321                 const struct iio_chan_spec *chan, enum iio_event_type type,
 322                 enum iio_event_direction dir, enum iio_event_info info,
 323                 int val, int val2)
 324 {
 325         struct tmp007_data *data = iio_priv(indio_dev);
 326         u8 reg;
 327
 328         switch (chan->channel2) {
 329         case IIO_MOD_TEMP_AMBIENT:
 330                 if (dir == IIO_EV_DIR_RISING)
 331                         reg = TMP007_TDIE_HIGH_LIMIT;
 332                 else
 333                         reg = TMP007_TDIE_LOW_LIMIT;
 334                 break;
 335         case IIO_MOD_TEMP_OBJECT:
 336                 if (dir == IIO_EV_DIR_RISING)
 337                         reg = TMP007_TOBJ_HIGH_LIMIT;
 338                 else
 339                         reg = TMP007_TOBJ_LOW_LIMIT;
 340                 break;
 341         default:
 342                 return -EINVAL;
 343         }
 344
 345         /* Full scale threshold value is +/- 256 degree Celsius */
 346         if (val < -256 || val > 255)
 347                 return -EINVAL;
 348
 349         /* Shift length 7 bits = 6(15:6) + 1(0.5 LSB) */
 350         return i2c_smbus_write_word_swapped(data->client, reg, (val << 7));
 351 }
 352
 353 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
 354
 355 static struct attribute *tmp007_attributes[] = {
 356         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 357         NULL
 358 };
 359
 360 static const struct attribute_group tmp007_attribute_group = {
 361         .attrs = tmp007_attributes,
 362 };
 363
 364 static const struct iio_event_spec tmp007_obj_event[] = {
 365         {
 366                 .type = IIO_EV_TYPE_THRESH,
 367                 .dir = IIO_EV_DIR_RISING,
 368                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 369                         BIT(IIO_EV_INFO_ENABLE),
 370         },
 371         {
 372                 .type = IIO_EV_TYPE_THRESH,
 373                 .dir = IIO_EV_DIR_FALLING,
 374                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 375                         BIT(IIO_EV_INFO_ENABLE),
 376         },
 377 };
 378
 379 static const struct iio_event_spec tmp007_die_event[] = {
 380         {
 381                 .type = IIO_EV_TYPE_THRESH,
 382                 .dir = IIO_EV_DIR_RISING,
 383                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 384                         BIT(IIO_EV_INFO_ENABLE),
 385         },
 386         {
 387                 .type = IIO_EV_TYPE_THRESH,
 388                 .dir = IIO_EV_DIR_FALLING,
 389                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 390                         BIT(IIO_EV_INFO_ENABLE),
 391         },
 392 };
 393
 394 static const struct iio_chan_spec tmp007_channels[] = {
 395         {
 396                 .type = IIO_TEMP,
 397                 .modified = 1,
 398                 .channel2 = IIO_MOD_TEMP_AMBIENT,
 399                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 400                                 BIT(IIO_CHAN_INFO_SCALE),
 401                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 402                 .event_spec = tmp007_die_event,
 403                 .num_event_specs = ARRAY_SIZE(tmp007_die_event),
 404         },
 405         {
 406                 .type = IIO_TEMP,
 407                 .modified = 1,
 408                 .channel2 = IIO_MOD_TEMP_OBJECT,
 409                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 410                                 BIT(IIO_CHAN_INFO_SCALE),
 411                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 412                 .event_spec = tmp007_obj_event,
 413                 .num_event_specs = ARRAY_SIZE(tmp007_obj_event),
 414         }
 415 };
 416
 417 static const struct iio_info tmp007_info = {
 418         .read_raw = tmp007_read_raw,
 419         .write_raw = tmp007_write_raw,
 420         .read_event_config = tmp007_read_event_config,
 421         .write_event_config = tmp007_write_event_config,
 422         .read_event_value = tmp007_read_thresh,
 423         .write_event_value = tmp007_write_thresh,
 424         .attrs = &tmp007_attribute_group,
 425 };
 426
 427 static bool tmp007_identify(struct i2c_client *client)
 428 {
 429         int manf_id, dev_id;
 430
 431         manf_id = i2c_smbus_read_word_swapped(client, TMP007_MANUFACTURER_ID);
 432         if (manf_id < 0)
 433                 return false;
 434
 435         dev_id = i2c_smbus_read_word_swapped(client, TMP007_DEVICE_ID);
 436         if (dev_id < 0)
 437                 return false;
 438
 439         return (manf_id == TMP007_MANUFACTURER_MAGIC && dev_id == TMP007_DEVICE_MAGIC);
 440 }
 441
 442 static int tmp007_probe(struct i2c_client *client,
 443                         const struct i2c_device_id *tmp007_id)
 444 {
 445         struct tmp007_data *data;
 446         struct iio_dev *indio_dev;
 447         int ret;
 448
 449         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 450                 return -EOPNOTSUPP;
 451
 452         if (!tmp007_identify(client)) {
 453                 dev_err(&client->dev, "TMP007 not found\n");
 454                 return -ENODEV;
 455         }
 456
 457         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 458         if (!indio_dev)
 459                 return -ENOMEM;
 460
 461         data = iio_priv(indio_dev);
 462         i2c_set_clientdata(client, indio_dev);
 463         data->client = client;
 464         mutex_init(&data->lock);
 465
 466         indio_dev->name = "tmp007";
 467         indio_dev->modes = INDIO_DIRECT_MODE;
 468         indio_dev->info = &tmp007_info;
 469
 470         indio_dev->channels = tmp007_channels;
 471         indio_dev->num_channels = ARRAY_SIZE(tmp007_channels);
 472
 473         /*
 474          * Set Configuration register:
 475          * 1. Conversion ON
 476          * 2. ALERT enable
 477          * 3. Transient correction enable
 478          */
 479
 480         ret = i2c_smbus_read_word_swapped(data->client, TMP007_CONFIG);
 481         if (ret < 0)
 482                 return ret;
 483
 484         data->config = ret;
 485         data->config |= (TMP007_CONFIG_CONV_EN | TMP007_CONFIG_ALERT_EN | TMP007_CONFIG_TC_EN);
 486
 487         ret = i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 488                                         data->config);
 489         if (ret < 0)
 490                 return ret;
 491
 492         /*
 493          * Only the following flags can activate ALERT pin. Data conversion/validity flags
 494          * flags can still be polled for getting temperature data
 495          *
 496          * Set Status Mask register:
 497          * 1. Object temperature high limit enable
 498          * 2. Object temperature low limit enable
 499          * 3. TDIE temperature high limit enable
 500          * 4. TDIE temperature low limit enable
 501          */
 502
 503         ret = i2c_smbus_read_word_swapped(data->client, TMP007_STATUS_MASK);
 504         if (ret < 0)
 505                 goto error_powerdown;
 506
 507         data->status_mask = ret;
 508         data->status_mask |= (TMP007_STATUS_OHF | TMP007_STATUS_OLF
 509                                 | TMP007_STATUS_LHF | TMP007_STATUS_LLF);
 510
 511         ret = i2c_smbus_write_word_swapped(data->client, TMP007_STATUS_MASK, data->status_mask);
 512         if (ret < 0)
 513                 goto error_powerdown;
 514
 515         if (client->irq) {
 516                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 517                                 NULL, tmp007_interrupt_handler,
 518                                 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 519                                 tmp007_id->name, indio_dev);
 520                 if (ret) {
 521                         dev_err(&client->dev, "irq request error %d\n", -ret);
 522                         goto error_powerdown;
 523                 }
 524         }
 525
 526         return iio_device_register(indio_dev);
 527
 528 error_powerdown:
 529         tmp007_powerdown(data);
 530
 531         return ret;
 532 }
 533
 534 static int tmp007_remove(struct i2c_client *client)
 535 {
 536         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 537         struct tmp007_data *data = iio_priv(indio_dev);
 538
 539         iio_device_unregister(indio_dev);
 540         tmp007_powerdown(data);
 541
 542         return 0;
 543 }
 544
 545 #ifdef CONFIG_PM_SLEEP
 546 static int tmp007_suspend(struct device *dev)
 547 {
 548         struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 549                         to_i2c_client(dev)));
 550
 551         return tmp007_powerdown(data);
 552 }
 553
 554 static int tmp007_resume(struct device *dev)
 555 {
 556         struct tmp007_data *data = iio_priv(i2c_get_clientdata(
 557                         to_i2c_client(dev)));
 558
 559         return i2c_smbus_write_word_swapped(data->client, TMP007_CONFIG,
 560                         data->config | TMP007_CONFIG_CONV_EN);
 561 }
 562 #endif
 563
 564 static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
 565
 566 static const struct of_device_id tmp007_of_match[] = {
 567         { .compatible = "ti,tmp007", },
 568         { },
 569 };
 570 MODULE_DEVICE_TABLE(of, tmp007_of_match);
 571
 572 static const struct i2c_device_id tmp007_id[] = {
 573         { "tmp007", 0 },
 574         { }
 575 };
 576 MODULE_DEVICE_TABLE(i2c, tmp007_id);
 577
 578 static struct i2c_driver tmp007_driver = {
 579         .driver = {
 580                 .name   = "tmp007",
 581                 .of_match_table = tmp007_of_match,
 582                 .pm     = &tmp007_pm_ops,
 583         },
 584         .probe          = tmp007_probe,
 585         .remove         = tmp007_remove,
 586         .id_table       = tmp007_id,
 587 };
 588 module_i2c_driver(tmp007_driver);
 589
 590 MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
 591 MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
 592 MODULE_LICENSE("GPL");