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 #include <linux/time.h>
  28
  29 #define HDC100X_REG_TEMP                        0x00
  30 #define HDC100X_REG_HUMIDITY                    0x01
  31
  32 #define HDC100X_REG_CONFIG                      0x02
  33 #define HDC100X_REG_CONFIG_ACQ_MODE             BIT(12)
  34 #define HDC100X_REG_CONFIG_HEATER_EN            BIT(13)
  35
  36 struct hdc100x_data {
  37         struct i2c_client *client;
  38         struct mutex lock;
  39         u16 config;
  40
  41         /* integration time of the sensor */
  42         int adc_int_us[2];
  43         /* Ensure natural alignment of timestamp */
  44         struct {
  45                 __be16 channels[2];
  46                 s64 ts __aligned(8);
  47         } scan;
  48 };
  49
  50 /* integration time in us */
  51 static const int hdc100x_int_time[][3] = {
  52         { 6350, 3650, 0 },      /* IIO_TEMP channel*/
  53         { 6500, 3850, 2500 },   /* IIO_HUMIDITYRELATIVE channel */
  54 };
  55
  56 /* HDC100X_REG_CONFIG shift and mask values */
  57 static const struct {
  58         int shift;
  59         int mask;
  60 } hdc100x_resolution_shift[2] = {
  61         { /* IIO_TEMP channel */
  62                 .shift = 10,
  63                 .mask = 1
  64         },
  65         { /* IIO_HUMIDITYRELATIVE channel */
  66                 .shift = 8,
  67                 .mask = 3,
  68         },
  69 };
  70
  71 static IIO_CONST_ATTR(temp_integration_time_available,
  72                 "0.00365 0.00635");
  73
  74 static IIO_CONST_ATTR(humidityrelative_integration_time_available,
  75                 "0.0025 0.00385 0.0065");
  76
  77 static IIO_CONST_ATTR(out_current_heater_raw_available,
  78                 "0 1");
  79
  80 static struct attribute *hdc100x_attributes[] = {
  81         &iio_const_attr_temp_integration_time_available.dev_attr.attr,
  82         &iio_const_attr_humidityrelative_integration_time_available.dev_attr.attr,
  83         &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
  84         NULL
  85 };
  86
  87 static const struct attribute_group hdc100x_attribute_group = {
  88         .attrs = hdc100x_attributes,
  89 };
  90
  91 static const struct iio_chan_spec hdc100x_channels[] = {
  92         {
  93                 .type = IIO_TEMP,
  94                 .address = HDC100X_REG_TEMP,
  95                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  96                         BIT(IIO_CHAN_INFO_SCALE) |
  97                         BIT(IIO_CHAN_INFO_INT_TIME) |
  98                         BIT(IIO_CHAN_INFO_OFFSET),
  99                 .scan_index = 0,
 100                 .scan_type = {
 101                         .sign = 's',
 102                         .realbits = 16,
 103                         .storagebits = 16,
 104                         .endianness = IIO_BE,
 105                 },
 106         },
 107         {
 108                 .type = IIO_HUMIDITYRELATIVE,
 109                 .address = HDC100X_REG_HUMIDITY,
 110                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 111                         BIT(IIO_CHAN_INFO_SCALE) |
 112                         BIT(IIO_CHAN_INFO_INT_TIME),
 113                 .scan_index = 1,
 114                 .scan_type = {
 115                         .sign = 'u',
 116                         .realbits = 16,
 117                         .storagebits = 16,
 118                         .endianness = IIO_BE,
 119                 },
 120         },
 121         {
 122                 .type = IIO_CURRENT,
 123                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 124                 .extend_name = "heater",
 125                 .output = 1,
 126                 .scan_index = -1,
 127         },
 128         IIO_CHAN_SOFT_TIMESTAMP(2),
 129 };
 130
 131 static const unsigned long hdc100x_scan_masks[] = {0x3, 0};
 132
 133 static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val)
 134 {
 135         int tmp = (~mask & data->config) | val;
 136         int ret;
 137
 138         ret = i2c_smbus_write_word_swapped(data->client,
 139                                                 HDC100X_REG_CONFIG, tmp);
 140         if (!ret)
 141                 data->config = tmp;
 142
 143         return ret;
 144 }
 145
 146 static int hdc100x_set_it_time(struct hdc100x_data *data, int chan, int val2)
 147 {
 148         int shift = hdc100x_resolution_shift[chan].shift;
 149         int ret = -EINVAL;
 150         int i;
 151
 152         for (i = 0; i < ARRAY_SIZE(hdc100x_int_time[chan]); i++) {
 153                 if (val2 && val2 == hdc100x_int_time[chan][i]) {
 154                         ret = hdc100x_update_config(data,
 155                                 hdc100x_resolution_shift[chan].mask << shift,
 156                                 i << shift);
 157                         if (!ret)
 158                                 data->adc_int_us[chan] = val2;
 159                         break;
 160                 }
 161         }
 162
 163         return ret;
 164 }
 165
 166 static int hdc100x_get_measurement(struct hdc100x_data *data,
 167                                    struct iio_chan_spec const *chan)
 168 {
 169         struct i2c_client *client = data->client;
 170         int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC;
 171         int ret;
 172         __be16 val;
 173
 174         /* start measurement */
 175         ret = i2c_smbus_write_byte(client, chan->address);
 176         if (ret < 0) {
 177                 dev_err(&client->dev, "cannot start measurement");
 178                 return ret;
 179         }
 180
 181         /* wait for integration time to pass */
 182         usleep_range(delay, delay + 1000);
 183
 184         /* read measurement */
 185         ret = i2c_master_recv(data->client, (char *)&val, sizeof(val));
 186         if (ret < 0) {
 187                 dev_err(&client->dev, "cannot read sensor data\n");
 188                 return ret;
 189         }
 190         return be16_to_cpu(val);
 191 }
 192
 193 static int hdc100x_get_heater_status(struct hdc100x_data *data)
 194 {
 195         return !!(data->config & HDC100X_REG_CONFIG_HEATER_EN);
 196 }
 197
 198 static int hdc100x_read_raw(struct iio_dev *indio_dev,
 199                             struct iio_chan_spec const *chan, int *val,
 200                             int *val2, long mask)
 201 {
 202         struct hdc100x_data *data = iio_priv(indio_dev);
 203
 204         switch (mask) {
 205         case IIO_CHAN_INFO_RAW: {
 206                 int ret;
 207
 208                 mutex_lock(&data->lock);
 209                 if (chan->type == IIO_CURRENT) {
 210                         *val = hdc100x_get_heater_status(data);
 211                         ret = IIO_VAL_INT;
 212                 } else {
 213                         ret = iio_device_claim_direct_mode(indio_dev);
 214                         if (ret) {
 215                                 mutex_unlock(&data->lock);
 216                                 return ret;
 217                         }
 218
 219                         ret = hdc100x_get_measurement(data, chan);
 220                         iio_device_release_direct_mode(indio_dev);
 221                         if (ret >= 0) {
 222                                 *val = ret;
 223                                 ret = IIO_VAL_INT;
 224                         }
 225                 }
 226                 mutex_unlock(&data->lock);
 227                 return ret;
 228         }
 229         case IIO_CHAN_INFO_INT_TIME:
 230                 *val = 0;
 231                 *val2 = data->adc_int_us[chan->address];
 232                 return IIO_VAL_INT_PLUS_MICRO;
 233         case IIO_CHAN_INFO_SCALE:
 234                 if (chan->type == IIO_TEMP) {
 235                         *val = 165000;
 236                         *val2 = 65536;
 237                         return IIO_VAL_FRACTIONAL;
 238                 } else {
 239                         *val = 100000;
 240                         *val2 = 65536;
 241                         return IIO_VAL_FRACTIONAL;
 242                 }
 243                 break;
 244         case IIO_CHAN_INFO_OFFSET:
 245                 *val = -15887;
 246                 *val2 = 515151;
 247                 return IIO_VAL_INT_PLUS_MICRO;
 248         default:
 249                 return -EINVAL;
 250         }
 251 }
 252
 253 static int hdc100x_write_raw(struct iio_dev *indio_dev,
 254                              struct iio_chan_spec const *chan,
 255                              int val, int val2, long mask)
 256 {
 257         struct hdc100x_data *data = iio_priv(indio_dev);
 258         int ret = -EINVAL;
 259
 260         switch (mask) {
 261         case IIO_CHAN_INFO_INT_TIME:
 262                 if (val != 0)
 263                         return -EINVAL;
 264
 265                 mutex_lock(&data->lock);
 266                 ret = hdc100x_set_it_time(data, chan->address, val2);
 267                 mutex_unlock(&data->lock);
 268                 return ret;
 269         case IIO_CHAN_INFO_RAW:
 270                 if (chan->type != IIO_CURRENT || val2 != 0)
 271                         return -EINVAL;
 272
 273                 mutex_lock(&data->lock);
 274                 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN,
 275                                         val ? HDC100X_REG_CONFIG_HEATER_EN : 0);
 276                 mutex_unlock(&data->lock);
 277                 return ret;
 278         default:
 279                 return -EINVAL;
 280         }
 281 }
 282
 283 static int hdc100x_buffer_postenable(struct iio_dev *indio_dev)
 284 {
 285         struct hdc100x_data *data = iio_priv(indio_dev);
 286         int ret;
 287
 288         /* Buffer is enabled. First set ACQ Mode, then attach poll func */
 289         mutex_lock(&data->lock);
 290         ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE,
 291                                     HDC100X_REG_CONFIG_ACQ_MODE);
 292         mutex_unlock(&data->lock);
 293         if (ret)
 294                 return ret;
 295
 296         return iio_triggered_buffer_postenable(indio_dev);
 297 }
 298
 299 static int hdc100x_buffer_predisable(struct iio_dev *indio_dev)
 300 {
 301         struct hdc100x_data *data = iio_priv(indio_dev);
 302         int ret;
 303
 304         /* First detach poll func, then reset ACQ mode. OK to disable buffer */
 305         ret = iio_triggered_buffer_predisable(indio_dev);
 306         if (ret)
 307                 return ret;
 308
 309         mutex_lock(&data->lock);
 310         ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
 311         mutex_unlock(&data->lock);
 312
 313         return ret;
 314 }
 315
 316 static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = {
 317         .postenable  = hdc100x_buffer_postenable,
 318         .predisable  = hdc100x_buffer_predisable,
 319 };
 320
 321 static irqreturn_t hdc100x_trigger_handler(int irq, void *p)
 322 {
 323         struct iio_poll_func *pf = p;
 324         struct iio_dev *indio_dev = pf->indio_dev;
 325         struct hdc100x_data *data = iio_priv(indio_dev);
 326         struct i2c_client *client = data->client;
 327         int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC;
 328         int ret;
 329
 330         /* dual read starts at temp register */
 331         mutex_lock(&data->lock);
 332         ret = i2c_smbus_write_byte(client, HDC100X_REG_TEMP);
 333         if (ret < 0) {
 334                 dev_err(&client->dev, "cannot start measurement\n");
 335                 goto err;
 336         }
 337         usleep_range(delay, delay + 1000);
 338
 339         ret = i2c_master_recv(client, (u8 *)data->scan.channels, 4);
 340         if (ret < 0) {
 341                 dev_err(&client->dev, "cannot read sensor data\n");
 342                 goto err;
 343         }
 344
 345         iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
 346                                            iio_get_time_ns(indio_dev));
 347 err:
 348         mutex_unlock(&data->lock);
 349         iio_trigger_notify_done(indio_dev->trig);
 350
 351         return IRQ_HANDLED;
 352 }
 353
 354 static const struct iio_info hdc100x_info = {
 355         .read_raw = hdc100x_read_raw,
 356         .write_raw = hdc100x_write_raw,
 357         .attrs = &hdc100x_attribute_group,
 358 };
 359
 360 static int hdc100x_probe(struct i2c_client *client,
 361                          const struct i2c_device_id *id)
 362 {
 363         struct iio_dev *indio_dev;
 364         struct hdc100x_data *data;
 365         int ret;
 366
 367         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA |
 368                                      I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
 369                 return -EOPNOTSUPP;
 370
 371         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 372         if (!indio_dev)
 373                 return -ENOMEM;
 374
 375         data = iio_priv(indio_dev);
 376         i2c_set_clientdata(client, indio_dev);
 377         data->client = client;
 378         mutex_init(&data->lock);
 379
 380         indio_dev->dev.parent = &client->dev;
 381         indio_dev->name = dev_name(&client->dev);
 382         indio_dev->modes = INDIO_DIRECT_MODE;
 383         indio_dev->info = &hdc100x_info;
 384
 385         indio_dev->channels = hdc100x_channels;
 386         indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels);
 387         indio_dev->available_scan_masks = hdc100x_scan_masks;
 388
 389         /* be sure we are in a known state */
 390         hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]);
 391         hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]);
 392         hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0);
 393
 394         ret = iio_triggered_buffer_setup(indio_dev, NULL,
 395                                          hdc100x_trigger_handler,
 396                                          &hdc_buffer_setup_ops);
 397         if (ret < 0) {
 398                 dev_err(&client->dev, "iio triggered buffer setup failed\n");
 399                 return ret;
 400         }
 401         ret = iio_device_register(indio_dev);
 402         if (ret < 0)
 403                 iio_triggered_buffer_cleanup(indio_dev);
 404
 405         return ret;
 406 }
 407
 408 static int hdc100x_remove(struct i2c_client *client)
 409 {
 410         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 411
 412         iio_device_unregister(indio_dev);
 413         iio_triggered_buffer_cleanup(indio_dev);
 414
 415         return 0;
 416 }
 417
 418 static const struct i2c_device_id hdc100x_id[] = {
 419         { "hdc100x", 0 },
 420         { "hdc1000", 0 },
 421         { "hdc1008", 0 },
 422         { "hdc1010", 0 },
 423         { "hdc1050", 0 },
 424         { "hdc1080", 0 },
 425         { }
 426 };
 427 MODULE_DEVICE_TABLE(i2c, hdc100x_id);
 428
 429 static const struct of_device_id hdc100x_dt_ids[] = {
 430         { .compatible = "ti,hdc1000" },
 431         { .compatible = "ti,hdc1008" },
 432         { .compatible = "ti,hdc1010" },
 433         { .compatible = "ti,hdc1050" },
 434         { .compatible = "ti,hdc1080" },
 435         { }
 436 };
 437 MODULE_DEVICE_TABLE(of, hdc100x_dt_ids);
 438
 439 static struct i2c_driver hdc100x_driver = {
 440         .driver = {
 441                 .name   = "hdc100x",
 442                 .of_match_table = of_match_ptr(hdc100x_dt_ids),
 443         },
 444         .probe = hdc100x_probe,
 445         .remove = hdc100x_remove,
 446         .id_table = hdc100x_id,
 447 };
 448 module_i2c_driver(hdc100x_driver);
 449
 450 MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
 451 MODULE_DESCRIPTION("TI HDC100x humidity and temperature sensor driver");
 452 MODULE_LICENSE("GPL");