linux/drivers/iio/temperature/tmp007.c
<<
>>
Prefs
   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
  63struct tmp007_data {
  64        struct i2c_client *client;
  65        struct mutex lock;
  66        u16 config;
  67        u16 status_mask;
  68};
  69
  70static const int tmp007_avgs[5][2] = { {4, 0}, {2, 0}, {1, 0},
  71                                        {0, 500000}, {0, 250000} };
  72
  73static 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
  95static 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
 101static 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
 146static 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
 171static 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
 217static 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
 257static 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
 284static 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
 320static 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
 353static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
 354
 355static struct attribute *tmp007_attributes[] = {
 356        &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 357        NULL
 358};
 359
 360static const struct attribute_group tmp007_attribute_group = {
 361        .attrs = tmp007_attributes,
 362};
 363
 364static 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
 379static 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
 394static 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
 417static 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
 427static 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
 442static 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
 528error_powerdown:
 529        tmp007_powerdown(data);
 530
 531        return ret;
 532}
 533
 534static 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
 546static 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
 554static 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
 564static SIMPLE_DEV_PM_OPS(tmp007_pm_ops, tmp007_suspend, tmp007_resume);
 565
 566static const struct of_device_id tmp007_of_match[] = {
 567        { .compatible = "ti,tmp007", },
 568        { },
 569};
 570MODULE_DEVICE_TABLE(of, tmp007_of_match);
 571
 572static const struct i2c_device_id tmp007_id[] = {
 573        { "tmp007", 0 },
 574        { }
 575};
 576MODULE_DEVICE_TABLE(i2c, tmp007_id);
 577
 578static 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};
 588module_i2c_driver(tmp007_driver);
 589
 590MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
 591MODULE_DESCRIPTION("TI TMP007 IR thermopile sensor driver");
 592MODULE_LICENSE("GPL");
 593