drivers/iio/humidity/hdc100x.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * hdc100x.c - Support for the TI HDC100x temperature + humidity sensors
   4  *
   5  * Copyright (C) 2015, 2018
   6  * Author: Matt Ranostay <matt.ranostay@konsulko.com>
   7  *
   8  * Datasheets:
   9  * http://www.ti.com/product/HDC1000/datasheet
  10  * http://www.ti.com/product/HDC1008/datasheet
  11  * http://www.ti.com/product/HDC1010/datasheet
  12  * http://www.ti.com/product/HDC1050/datasheet
  13  * http://www.ti.com/product/HDC1080/datasheet
  14  */
  15
  16 #include <linux/delay.h>
  17 #include <linux/module.h>
  18 #include <linux/init.h>
  19 #include <linux/i2c.h>
  20
  21 #include <linux/iio/iio.h>
  22 #include <linux/iio/sysfs.h>
  23 #include <linux/iio/buffer.h>
  24 #include <linux/iio/trigger_consumer.h>
  25 #include <linux/iio/triggered_buffer.h>
  26
  27 #define HDC100X_REG_TEMP                        0x00
  28 #define HDC100X_REG_HUMIDITY                    0x01
  29
  30 #define HDC100X_REG_CONFIG                      0x02
  31 #define HDC100X_REG_CONFIG_ACQ_MODE             BIT(12)
  32 #define HDC100X_REG_CONFIG_HEATER_EN            BIT(13)
  33
  34 struct hdc100x_data {
  35         struct i2c_client *client;
  36         struct mutex lock;
  37         u16 config;
  38
  39         /* integration time of the sensor */
  40         int adc_int_us[2];
  41 };
  42
  43 /* integration time in us */
  44 static const int hdc100x_int_time[][3] = {
  45         { 6350, 3650, 0 },      /* IIO_TEMP channel*/
  46         { 6500, 3850, 2500 },   /* IIO_HUMIDITYRELATIVE channel */
  47 };
  48
  49 /* HDC100X_REG_CONFIG shift and mask values */
  50 static const struct {
  51         int shift;
  52         int mask;
  53 } hdc100x_resolution_shift[2] = {
  54         { /* IIO_TEMP channel */
  55                 .shift = 10,
  56                 .mask = 1
  57         },
  58         { /* IIO_HUMIDITYRELATIVE channel */
  59                 .shift = 8,
  60                 .mask = 3,
  61         },
  62 };
  63
  64 static IIO_CONST_ATTR(temp_integration_time_available,
  65                 "0.00365 0.00635");
  66
  67 static IIO_CONST_ATTR(humidityrelative_integration_time_available,
  68                 "0.0025 0.00385 0.0065");
  69
  70 static IIO_CONST_ATTR(out_current_heater_raw_available,
  71                 "0 1");
  72
  73 static struct attribute *hdc100x_attributes[] = {
  74         &iio_const_attr_temp_integration_time_available.dev_attr.attr,
  75         &iio_const_attr_humidityrelative_integration_time_available.dev_attr.attr,
  76         &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
  77         NULL
  78 };
  79
  80 static const struct attribute_group hdc100x_attribute_group = {
  81         .attrs = hdc100x_attributes,
  82 };
  83
  84 static const struct iio_chan_spec hdc100x_channels[] = {
  85         {
  86                 .type = IIO_TEMP,
  87                 .address = HDC100X_REG_TEMP,
  88                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  89                         BIT(IIO_CHAN_INFO_SCALE) |
  90                         BIT(IIO_CHAN_INFO_INT_TIME) |
  91                         BIT(IIO_CHAN_INFO_OFFSET),
  92                 .scan_index = 0,
  93                 .scan_type = {
  94                         .sign = 's',
  95                         .realbits = 16,
  96                         .storagebits = 16,
  97                         .endianness = IIO_BE,
  98                 },
  99         },
 100         {
 101                 .type = IIO_HUMIDITYRELATIVE,
 102                 .address = HDC100X_REG_HUMIDITY,
 103                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 104                         BIT(IIO_CHAN_INFO_SCALE) |
 105                         BIT(IIO_CHAN_INFO_INT_TIME),
 106                 .scan_index = 1,
 107                 .scan_type = {
 108                         .sign = 'u',
 109                         .realbits = 16,
 110                         .storagebits = 16,
 111                         .endianness = IIO_BE,
 112                 },
 113         },
 114         {
 115                 .type = IIO_CURRENT,
 116                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 117                 .extend_name = "heater",
 118                 .output = 1,
 119                 .scan_index = -1,
 120         },
 121         IIO_CHAN_SOFT_TIMESTAMP(2),
 122 };
 123
 124 static const unsigned long hdc100x_scan_masks[] = {0x3, 0};
 125
 126 static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val)
 127 {
 128         int tmp = (~mask & data->config) | val;
 129         int ret;
 130
 131         ret = i2c_smbus_write_word_swapped(data->client,
 132                                                 HDC100X_REG_CONFIG, tmp);
 133         if (!ret)
 134                 data->config = tmp;
 135
 136         return ret;
 137 }
 138
 139 static int hdc100x_set_it_time(struct hdc100x_data *data, int chan, int val2)
 140 {
 141         int shift = hdc100x_resolution_shift[chan].shift;
 142         int ret = -EINVAL;
 143         int i;
 144
 145         for (i = 0; i < ARRAY_SIZE(hdc100x_int_time[chan]); i++) {
 146                 if (val2 && val2 == hdc100x_int_time[chan][i]) {
 147                         ret = hdc100x_update_config(data,
 148                                 hdc100x_resolution_shift[chan].mask << shift,
 149                                 i << shift);
 150                         if (!ret)
 151                                 data->adc_int_us[chan] = val2;
 152                         break;
 153                 }
 154         }
 155
 156         return ret;
 157 }
 158
 159 static int hdc100x_get_measurement(struct hdc100x_data *data,
 160                                    struct iio_chan_spec const *chan)
 161 {
 162         struct i2c_client *client = data->client;
 163         int delay = data->adc_int_us[chan->address];
 164         int ret;
 165         __be16 val;
 166
 167         /* start measurement */
 168         ret = i2c_smbus_write_byte(client, chan->address);
 169         if (ret < 0) {
 170                 dev_err(&client->dev, "cannot start measurement");
 171                 return ret;
 172         }
 173
 174         /* wait for integration time to pass */
 175         usleep_range(delay, delay + 1000);
 176
 177         /* read measurement */
 178         ret = i2c_master_recv(data->client, (char *)&val, sizeof(val));
 179         if (ret < 0) {
 180                 dev_err(&client->dev, "cannot read sensor data\n");
 181                 return ret;
 182         }
 183         return be16_to_cpu(val);
 184 }
 185
 186 static int hdc100x_get_heater_status(struct hdc100x_data *data)
 187 {
 188         return !!(data->config & HDC100X_REG_CONFIG_HEATER_EN);
 189 }
 190
 191 static int hdc100x_read_raw(struct iio_dev *indio_dev,
 192                             struct iio_chan_spec const *chan, int *val,
 193                             int *val2, long mask)
 194 {
 195         struct hdc100x_data *data = iio_priv(indio_dev);
 196
 197         switch (mask) {
 198         case IIO_CHAN_INFO_RAW: {
 199                 int ret;
 200
 201                 mutex_lock(&data->lock);
 202                 if (chan->type == IIO_CURRENT) {
 203                         *val = hdc100x_get_heater_status(data);
 204                         ret = IIO_VAL_INT;
 205                 } else {
 206                         ret = iio_device_claim_direct_mode(indio_dev);
 207                         if (ret) {
 208                                 mutex_unlock(&data->lock);
 209                                 return ret;
 210                         }
 211
 212                         ret = hdc100x_get_measurement(data, chan);
 213                         iio_device_release_direct_mode(indio_dev);
 214                         if (ret >= 0) {
 215                                 *val = ret;
 216                                 ret = IIO_VAL_INT;
 217                         }
 218                 }
 219                 mutex_unlock(&data->lock);
 220                 return ret;
 221         }
 222         case IIO_CHAN_INFO_INT_TIME:
 223                 *val = 0;
 224                 *val2 = data->adc_int_us[chan->address];
 225                 return IIO_VAL_INT_PLUS_MICRO;
 226         case IIO_CHAN_INFO_SCALE:
 227                 if (chan->type == IIO_TEMP) {
 228                         *val = 165000;
 229                         *val2 = 65536;
 230                         return IIO_VAL_FRACTIONAL;
 231                 } else {
 232                         *val = 100;
 233                         *val2 = 65536;
 234                         return IIO_VAL_FRACTIONAL;
 235                 }
 236                 break;
 237         case IIO_CHAN_INFO_OFFSET:
 238                 *val = -15887;
 239                 *val2 = 515151;
 240                 return IIO_VAL_INT_PLUS_MICRO;
 241         default:
 242                 return -EINVAL;
 243         }
 244 }
 245
 246 static int hdc100x_write_raw(struct iio_dev *indio_dev,
 247                              struct iio_chan_spec const *chan,
 248                              int val, int val2, long mask)
 249 {
 250         struct hdc100x_data *data = iio_priv(indio_dev);
 251         int ret = -EINVAL;
 252
 253         switch (mask) {
 254         case IIO_CHAN_INFO_INT_TIME:
 255                 if (val != 0)
 256                         return -EINVAL;
 257
 258                 mutex_lock(&data->lock);
 259                 ret = hdc100x_set_it_time(data, chan->address, val2);
 260                 mutex_unlock(&data->lock);
 261                 return ret;
 262         case IIO_CHAN_INFO_RAW:
 263                 if (chan->type != IIO_CURRENT || val2 != 0)
 264                         return -EINVAL;
 265
 266                 mutex_lock(&data->lock);
 267                 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
 268                                         val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
 269                 mutex_unlock(&data->lock);
 270                 return ret;
 271         default:
 272                 return -EINVAL;
 273         }
 274 }
 275
 276 static int hdc100x_buffer_postenable(struct iio_dev *indio_dev)
 277 {
 278         struct hdc100x_data *data = iio_priv(indio_dev);
 279         int ret;
 280
 281         /* Buffer is enabled. First set ACQ Mode, then attach poll func */
 282         mutex_lock(&data->lock);
 283         ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,
 284                                     HDC100X_REG_CONFIG_ACQ_MODE);
 285         mutex_unlock(&data->lock);
 286         if (ret)
 287                 return ret;
 288
 289         return iio_triggered_buffer_postenable(indio_dev);
 290 }
 291
 292 static int hdc100x_buffer_predisable(struct iio_dev *indio_dev)
 293 {
 294         struct hdc100x_data *data = iio_priv(indio_dev);
 295         int ret;
 296
 297         /* First detach poll func, then reset ACQ mode. OK to disable buffer */
 298         ret = iio_triggered_buffer_predisable(indio_dev);
 299         if (ret)
 300                 return ret;
 301
 302         mutex_lock(&data->lock);
 303         ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
 304         mutex_unlock(&data->lock);
 305
 306         return ret;
 307 }
 308
 309 static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = {
 310         .postenable  = hdc100x_buffer_postenable,
 311         .predisable  = hdc100x_buffer_predisable,
 312 };
 313
 314 static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
 315 {
 316         struct iio_poll_func *pf = p;
 317         struct iio_dev *indio_dev = pf->indio_dev;
 318         struct hdc100x_data *data = iio_priv(indio_dev);
 319         struct i2c_client *client = data->client;
 320         int delay = data->adc_int_us[0] + data->adc_int_us[1];
 321         int ret;
 322         s16 buf[8];  /* 2x s16 + padding + 8 byte timestamp */
 323
 324         /* dual read starts at temp register */
 325         mutex_lock(&data->lock);
 326         ret = i2c_smbus_write_byte(client, HDC100X_REG_TEMP);
 327         if (ret < 0) {
 328                 dev_err(&client->dev, "cannot start measurement\n");
 329                 goto err;
 330         }
 331         usleep_range(delay, delay + 1000);
 332
 333         ret = i2c_master_recv(client, (u8 *)buf, 4);
 334         if (ret < 0) {
 335                 dev_err(&client->dev, "cannot read sensor data\n");
 336                 goto err;
 337         }
 338
 339         iio_push_to_buffers_with_timestamp(indio_dev, buf,
 340                                            iio_get_time_ns(indio_dev));
 341 err:
 342         mutex_unlock(&data->lock);
 343         iio_trigger_notify_done(indio_dev->trig);
 344
 345         return IRQ_HANDLED;
 346 }
 347
 348 static const struct iio_info hdc100x_info = {
 349         .read_raw = hdc100x_read_raw,
 350         .write_raw = hdc100x_write_raw,
 351         .attrs = &hdc100x_attribute_group,
 352 };
 353
 354 static int hdc100x_probe(struct i2c_client *client,
 355                          const struct i2c_device_id *id)
 356 {
 357         struct iio_dev *indio_dev;
 358         struct hdc100x_data *data;
 359         int ret;
 360
 361         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
 362                                      I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
 363                 return -EOPNOTSUPP;
 364
 365         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 366         if (!indio_dev)
 367                 return -ENOMEM;
 368
 369         data = iio_priv(indio_dev);
 370         i2c_set_clientdata(client, indio_dev);
 371         data->client = client;
 372         mutex_init(&data->lock);
 373
 374         indio_dev->dev.parent = &client->dev;
 375         indio_dev->name = dev_name(&client->dev);
 376         indio_dev->modes = INDIO_DIRECT_MODE;
 377         indio_dev->info = &hdc100x_info;
 378
 379         indio_dev->channels = hdc100x_channels;
 380         indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels);
 381         indio_dev->available_scan_masks = hdc100x_scan_masks;
 382
 383         /* be sure we are in a known state */
 384         hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]);
 385         hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]);
 386         hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
 387
 388         ret = iio_triggered_buffer_setup(indio_dev, NULL,
 389                                          hdc100x_trigger_handler,
 390                                          &hdc_buffer_setup_ops);
 391         if (ret < 0) {
 392                 dev_err(&client->dev, "iio triggered buffer setup failed\n");
 393                 return ret;
 394         }
 395         ret = iio_device_register(indio_dev);
 396         if (ret < 0)
 397                 iio_triggered_buffer_cleanup(indio_dev);
 398
 399         return ret;
 400 }
 401
 402 static int hdc100x_remove(struct i2c_client *client)
 403 {
 404         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 405
 406         iio_device_unregister(indio_dev);
 407         iio_triggered_buffer_cleanup(indio_dev);
 408
 409         return 0;
 410 }
 411
 412 static const struct i2c_device_id hdc100x_id[] = {
 413         { "hdc100x", 0 },
 414         { "hdc1000", 0 },
 415         { "hdc1008", 0 },
 416         { "hdc1010", 0 },
 417         { "hdc1050", 0 },
 418         { "hdc1080", 0 },
 419         { }
 420 };
 421 MODULE_DEVICE_TABLE(i2c, hdc100x_id);
 422
 423 static const struct of_device_id hdc100x_dt_ids[] = {
 424         { .compatible = "ti,hdc1000" },
 425         { .compatible = "ti,hdc1008" },
 426         { .compatible = "ti,hdc1010" },
 427         { .compatible = "ti,hdc1050" },
 428         { .compatible = "ti,hdc1080" },
 429         { }
 430 };
 431 MODULE_DEVICE_TABLE(of, hdc100x_dt_ids);
 432
 433 static struct i2c_driver hdc100x_driver = {
 434         .driver = {
 435                 .name   = "hdc100x",
 436                 .of_match_table = of_match_ptr(hdc100x_dt_ids),
 437         },
 438         .probe = hdc100x_probe,
 439         .remove = hdc100x_remove,
 440         .id_table = hdc100x_id,
 441 };
 442 module_i2c_driver(hdc100x_driver);
 443
 444 MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
 445 MODULE_DESCRIPTION("TI HDC100x humidity and temperature sensor driver");
 446 MODULE_LICENSE("GPL");