drivers/iio/humidity/hdc2010.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * hdc2010.c - Support for the TI HDC2010 and HDC2080
   4  * temperature + relative humidity sensors
   5  *
   6  * Copyright (C) 2020 Norphonic AS
   7  * Author: Eugene Zaikonnikov <ez@norphonic.com>
   8  *
   9  * Datasheet: https://www.ti.com/product/HDC2010/datasheet
  10  * Datasheet: https://www.ti.com/product/HDC2080/datasheet
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/i2c.h>
  16 #include <linux/bitops.h>
  17
  18 #include <linux/iio/iio.h>
  19 #include <linux/iio/sysfs.h>
  20
  21 #define HDC2010_REG_TEMP_LOW                    0x00
  22 #define HDC2010_REG_TEMP_HIGH                   0x01
  23 #define HDC2010_REG_HUMIDITY_LOW                0x02
  24 #define HDC2010_REG_HUMIDITY_HIGH               0x03
  25 #define HDC2010_REG_INTERRUPT_DRDY              0x04
  26 #define HDC2010_REG_TEMP_MAX                    0x05
  27 #define HDC2010_REG_HUMIDITY_MAX                0x06
  28 #define HDC2010_REG_INTERRUPT_EN                0x07
  29 #define HDC2010_REG_TEMP_OFFSET_ADJ             0x08
  30 #define HDC2010_REG_HUMIDITY_OFFSET_ADJ         0x09
  31 #define HDC2010_REG_TEMP_THR_L                  0x0a
  32 #define HDC2010_REG_TEMP_THR_H                  0x0b
  33 #define HDC2010_REG_RH_THR_L                    0x0c
  34 #define HDC2010_REG_RH_THR_H                    0x0d
  35 #define HDC2010_REG_RESET_DRDY_INT_CONF         0x0e
  36 #define HDC2010_REG_MEASUREMENT_CONF            0x0f
  37
  38 #define HDC2010_MEAS_CONF                       GENMASK(2, 1)
  39 #define HDC2010_MEAS_TRIG                       BIT(0)
  40 #define HDC2010_HEATER_EN                       BIT(3)
  41 #define HDC2010_AMM                             GENMASK(6, 4)
  42
  43 struct hdc2010_data {
  44         struct i2c_client *client;
  45         struct mutex lock;
  46         u8 measurement_config;
  47         u8 interrupt_config;
  48         u8 drdy_config;
  49 };
  50
  51 enum hdc2010_addr_groups {
  52         HDC2010_GROUP_TEMP = 0,
  53         HDC2010_GROUP_HUMIDITY,
  54 };
  55
  56 struct hdc2010_reg_record {
  57         unsigned long primary;
  58         unsigned long peak;
  59 };
  60
  61 static const struct hdc2010_reg_record hdc2010_reg_translation[] = {
  62         [HDC2010_GROUP_TEMP] = {
  63                 .primary = HDC2010_REG_TEMP_LOW,
  64                 .peak = HDC2010_REG_TEMP_MAX,
  65         },
  66         [HDC2010_GROUP_HUMIDITY] = {
  67                 .primary = HDC2010_REG_HUMIDITY_LOW,
  68                 .peak = HDC2010_REG_HUMIDITY_MAX,
  69         },
  70 };
  71
  72 static IIO_CONST_ATTR(out_current_heater_raw_available, "0 1");
  73
  74 static struct attribute *hdc2010_attributes[] = {
  75         &iio_const_attr_out_current_heater_raw_available.dev_attr.attr,
  76         NULL
  77 };
  78
  79 static const struct attribute_group hdc2010_attribute_group = {
  80         .attrs = hdc2010_attributes,
  81 };
  82
  83 static const struct iio_chan_spec hdc2010_channels[] = {
  84         {
  85                 .type = IIO_TEMP,
  86                 .address = HDC2010_GROUP_TEMP,
  87                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  88                         BIT(IIO_CHAN_INFO_PEAK) |
  89                         BIT(IIO_CHAN_INFO_OFFSET) |
  90                         BIT(IIO_CHAN_INFO_SCALE),
  91         },
  92         {
  93                 .type = IIO_HUMIDITYRELATIVE,
  94                 .address = HDC2010_GROUP_HUMIDITY,
  95                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  96                         BIT(IIO_CHAN_INFO_PEAK) |
  97                         BIT(IIO_CHAN_INFO_SCALE),
  98         },
  99         {
 100                 .type = IIO_CURRENT,
 101                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 102                 .extend_name = "heater",
 103                 .output = 1,
 104         },
 105 };
 106
 107 static int hdc2010_update_drdy_config(struct hdc2010_data *data,
 108                                              char mask, char val)
 109 {
 110         u8 tmp = (~mask & data->drdy_config) | val;
 111         int ret;
 112
 113         ret = i2c_smbus_write_byte_data(data->client,
 114                                         HDC2010_REG_RESET_DRDY_INT_CONF, tmp);
 115         if (ret)
 116                 return ret;
 117
 118         data->drdy_config = tmp;
 119
 120         return 0;
 121 }
 122
 123 static int hdc2010_get_prim_measurement_word(struct hdc2010_data *data,
 124                                              struct iio_chan_spec const *chan)
 125 {
 126         struct i2c_client *client = data->client;
 127         s32 ret;
 128
 129         ret = i2c_smbus_read_word_data(client,
 130                         hdc2010_reg_translation[chan->address].primary);
 131
 132         if (ret < 0)
 133                 dev_err(&client->dev, "Could not read sensor measurement word\n");
 134
 135         return ret;
 136 }
 137
 138 static int hdc2010_get_peak_measurement_byte(struct hdc2010_data *data,
 139                                              struct iio_chan_spec const *chan)
 140 {
 141         struct i2c_client *client = data->client;
 142         s32 ret;
 143
 144         ret = i2c_smbus_read_byte_data(client,
 145                         hdc2010_reg_translation[chan->address].peak);
 146
 147         if (ret < 0)
 148                 dev_err(&client->dev, "Could not read sensor measurement byte\n");
 149
 150         return ret;
 151 }
 152
 153 static int hdc2010_get_heater_status(struct hdc2010_data *data)
 154 {
 155         return !!(data->drdy_config & HDC2010_HEATER_EN);
 156 }
 157
 158 static int hdc2010_read_raw(struct iio_dev *indio_dev,
 159                             struct iio_chan_spec const *chan, int *val,
 160                             int *val2, long mask)
 161 {
 162         struct hdc2010_data *data = iio_priv(indio_dev);
 163
 164         switch (mask) {
 165         case IIO_CHAN_INFO_RAW: {
 166                 int ret;
 167
 168                 if (chan->type == IIO_CURRENT) {
 169                         *val = hdc2010_get_heater_status(data);
 170                         return IIO_VAL_INT;
 171                 }
 172                 ret = iio_device_claim_direct_mode(indio_dev);
 173                 if (ret)
 174                         return ret;
 175                 mutex_lock(&data->lock);
 176                 ret = hdc2010_get_prim_measurement_word(data, chan);
 177                 mutex_unlock(&data->lock);
 178                 iio_device_release_direct_mode(indio_dev);
 179                 if (ret < 0)
 180                         return ret;
 181                 *val = ret;
 182                 return IIO_VAL_INT;
 183         }
 184         case IIO_CHAN_INFO_PEAK: {
 185                 int ret;
 186
 187                 ret = iio_device_claim_direct_mode(indio_dev);
 188                 if (ret)
 189                         return ret;
 190                 mutex_lock(&data->lock);
 191                 ret = hdc2010_get_peak_measurement_byte(data, chan);
 192                 mutex_unlock(&data->lock);
 193                 iio_device_release_direct_mode(indio_dev);
 194                 if (ret < 0)
 195                         return ret;
 196                 /* Scaling up the value so we can use same offset as RAW */
 197                 *val = ret * 256;
 198                 return IIO_VAL_INT;
 199         }
 200         case IIO_CHAN_INFO_SCALE:
 201                 *val2 = 65536;
 202                 if (chan->type == IIO_TEMP)
 203                         *val = 165000;
 204                 else
 205                         *val = 100000;
 206                 return IIO_VAL_FRACTIONAL;
 207         case IIO_CHAN_INFO_OFFSET:
 208                 *val = -15887;
 209                 *val2 = 515151;
 210                 return IIO_VAL_INT_PLUS_MICRO;
 211         default:
 212                 return -EINVAL;
 213         }
 214 }
 215
 216 static int hdc2010_write_raw(struct iio_dev *indio_dev,
 217                              struct iio_chan_spec const *chan,
 218                              int val, int val2, long mask)
 219 {
 220         struct hdc2010_data *data = iio_priv(indio_dev);
 221         int new, ret;
 222
 223         switch (mask) {
 224         case IIO_CHAN_INFO_RAW:
 225                 if (chan->type != IIO_CURRENT || val2 != 0)
 226                         return -EINVAL;
 227
 228                 switch (val) {
 229                 case 1:
 230                         new = HDC2010_HEATER_EN;
 231                         break;
 232                 case 0:
 233                         new = 0;
 234                         break;
 235                 default:
 236                         return -EINVAL;
 237                 }
 238
 239                 mutex_lock(&data->lock);
 240                 ret = hdc2010_update_drdy_config(data, HDC2010_HEATER_EN, new);
 241                 mutex_unlock(&data->lock);
 242                 return ret;
 243         default:
 244                 return -EINVAL;
 245         }
 246 }
 247
 248 static const struct iio_info hdc2010_info = {
 249         .read_raw = hdc2010_read_raw,
 250         .write_raw = hdc2010_write_raw,
 251         .attrs = &hdc2010_attribute_group,
 252 };
 253
 254 static int hdc2010_probe(struct i2c_client *client,
 255                          const struct i2c_device_id *id)
 256 {
 257         struct iio_dev *indio_dev;
 258         struct hdc2010_data *data;
 259         u8 tmp;
 260         int ret;
 261
 262         if (!i2c_check_functionality(client->adapter,
 263             I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C))
 264                 return -EOPNOTSUPP;
 265
 266         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 267         if (!indio_dev)
 268                 return -ENOMEM;
 269
 270         data = iio_priv(indio_dev);
 271         i2c_set_clientdata(client, indio_dev);
 272         data->client = client;
 273         mutex_init(&data->lock);
 274
 275         indio_dev->dev.parent = &client->dev;
 276         /*
 277          * As DEVICE ID register does not differentiate between
 278          * HDC2010 and HDC2080, we have the name hardcoded
 279          */
 280         indio_dev->name = "hdc2010";
 281         indio_dev->modes = INDIO_DIRECT_MODE;
 282         indio_dev->info = &hdc2010_info;
 283
 284         indio_dev->channels = hdc2010_channels;
 285         indio_dev->num_channels = ARRAY_SIZE(hdc2010_channels);
 286
 287         /* Enable Automatic Measurement Mode at 5Hz */
 288         ret = hdc2010_update_drdy_config(data, HDC2010_AMM, HDC2010_AMM);
 289         if (ret)
 290                 return ret;
 291
 292         /*
 293          * We enable both temp and humidity measurement.
 294          * However the measurement won't start even in AMM until triggered.
 295          */
 296         tmp = (data->measurement_config & ~HDC2010_MEAS_CONF) |
 297                 HDC2010_MEAS_TRIG;
 298
 299         ret = i2c_smbus_write_byte_data(client, HDC2010_REG_MEASUREMENT_CONF, tmp);
 300         if (ret) {
 301                 dev_warn(&client->dev, "Unable to set up measurement\n");
 302                 if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0))
 303                         dev_warn(&client->dev, "Unable to restore default AMM\n");
 304                 return ret;
 305         };
 306
 307         data->measurement_config = tmp;
 308
 309         return iio_device_register(indio_dev);
 310 }
 311
 312 static int hdc2010_remove(struct i2c_client *client)
 313 {
 314         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 315         struct hdc2010_data *data = iio_priv(indio_dev);
 316
 317         iio_device_unregister(indio_dev);
 318
 319         /* Disable Automatic Measurement Mode */
 320         if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0))
 321                 dev_warn(&client->dev, "Unable to restore default AMM\n");
 322
 323         return 0;
 324 }
 325
 326 static const struct i2c_device_id hdc2010_id[] = {
 327         { "hdc2010" },
 328         { "hdc2080" },
 329         { }
 330 };
 331 MODULE_DEVICE_TABLE(i2c, hdc2010_id);
 332
 333 static const struct of_device_id hdc2010_dt_ids[] = {
 334         { .compatible = "ti,hdc2010" },
 335         { .compatible = "ti,hdc2080" },
 336         { }
 337 };
 338 MODULE_DEVICE_TABLE(of, hdc2010_dt_ids);
 339
 340 static struct i2c_driver hdc2010_driver = {
 341         .driver = {
 342                 .name   = "hdc2010",
 343                 .of_match_table = hdc2010_dt_ids,
 344         },
 345         .probe = hdc2010_probe,
 346         .remove = hdc2010_remove,
 347         .id_table = hdc2010_id,
 348 };
 349 module_i2c_driver(hdc2010_driver);
 350
 351 MODULE_AUTHOR("Eugene Zaikonnikov <ez@norphonic.com>");
 352 MODULE_DESCRIPTION("TI HDC2010 humidity and temperature sensor driver");
 353 MODULE_LICENSE("GPL");