1 /* 2 * hdc100x.c - Support for the TI HDC100x temperature + humidity sensors 3 * 4 * Copyright (C) 2015 Matt Ranostay <mranostay@gmail.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * Datasheets: 17 * http://www.ti.com/product/HDC1000/datasheet 18 * http://www.ti.com/product/HDC1008/datasheet 19 * http://www.ti.com/product/HDC1010/datasheet 20 * http://www.ti.com/product/HDC1050/datasheet 21 * http://www.ti.com/product/HDC1080/datasheet 22 */ 23 24 #include <linux/delay.h> 25 #include <linux/module.h> 26 #include <linux/init.h> 27 #include <linux/i2c.h> 28 29 #include <linux/iio/iio.h> 30 #include <linux/iio/sysfs.h> 31 #include <linux/iio/buffer.h> 32 #include <linux/iio/trigger_consumer.h> 33 #include <linux/iio/triggered_buffer.h> 34 35 #define HDC100X_REG_TEMP 0x00 36 #define HDC100X_REG_HUMIDITY 0x01 37 38 #define HDC100X_REG_CONFIG 0x02 39 #define HDC100X_REG_CONFIG_ACQ_MODE BIT(12) 40 #define HDC100X_REG_CONFIG_HEATER_EN BIT(13) 41 42 struct hdc100x_data { 43 struct i2c_client *client; 44 struct mutex lock; 45 u16 config; 46 47 /* integration time of the sensor */ 48 int adc_int_us[2]; 49 }; 50 51 /* integration time in us */ 52 static const int hdc100x_int_time[][3] = { 53 { 6350, 3650, 0 }, /* IIO_TEMP channel*/ 54 { 6500, 3850, 2500 }, /* IIO_HUMIDITYRELATIVE channel */ 55 }; 56 57 /* HDC100X_REG_CONFIG shift and mask values */ 58 static const struct { 59 int shift; 60 int mask; 61 } hdc100x_resolution_shift[2] = { 62 { /* IIO_TEMP channel */ 63 .shift = 10, 64 .mask = 1 65 }, 66 { /* IIO_HUMIDITYRELATIVE channel */ 67 .shift = 8, 68 .mask = 3, 69 }, 70 }; 71 72 static IIO_CONST_ATTR(temp_integration_time_available, 73 "0.00365 0.00635"); 74 75 static IIO_CONST_ATTR(humidityrelative_integration_time_available, 76 "0.0025 0.00385 0.0065"); 77 78 static IIO_CONST_ATTR(out_current_heater_raw_available, 79 "0 1"); 80 81 static struct attribute *hdc100x_attributes[] = { 82 &iio_const_attr_temp_integration_time_available.dev_attr.attr, 83 &iio_const_attr_humidityrelative_integration_time_available.dev_attr.attr, 84 &iio_const_attr_out_current_heater_raw_available.dev_attr.attr, 85 NULL 86 }; 87 88 static const struct attribute_group hdc100x_attribute_group = { 89 .attrs = hdc100x_attributes, 90 }; 91 92 static const struct iio_chan_spec hdc100x_channels[] = { 93 { 94 .type = IIO_TEMP, 95 .address = HDC100X_REG_TEMP, 96 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 97 BIT(IIO_CHAN_INFO_SCALE) | 98 BIT(IIO_CHAN_INFO_INT_TIME) | 99 BIT(IIO_CHAN_INFO_OFFSET), 100 .scan_index = 0, 101 .scan_type = { 102 .sign = 's', 103 .realbits = 16, 104 .storagebits = 16, 105 .endianness = IIO_BE, 106 }, 107 }, 108 { 109 .type = IIO_HUMIDITYRELATIVE, 110 .address = HDC100X_REG_HUMIDITY, 111 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 112 BIT(IIO_CHAN_INFO_SCALE) | 113 BIT(IIO_CHAN_INFO_INT_TIME), 114 .scan_index = 1, 115 .scan_type = { 116 .sign = 'u', 117 .realbits = 16, 118 .storagebits = 16, 119 .endianness = IIO_BE, 120 }, 121 }, 122 { 123 .type = IIO_CURRENT, 124 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 125 .extend_name = "heater", 126 .output = 1, 127 .scan_index = -1, 128 }, 129 IIO_CHAN_SOFT_TIMESTAMP(2), 130 }; 131 132 static const unsigned long hdc100x_scan_masks[] = {0x3, 0}; 133 134 static int hdc100x_update_config(struct hdc100x_data *data, int mask, int val) 135 { 136 int tmp = (~mask & data->config) | val; 137 int ret; 138 139 ret = i2c_smbus_write_word_swapped(data->client, 140 HDC100X_REG_CONFIG, tmp); 141 if (!ret) 142 data->config = tmp; 143 144 return ret; 145 } 146 147 static int hdc100x_set_it_time(struct hdc100x_data *data, int chan, int val2) 148 { 149 int shift = hdc100x_resolution_shift[chan].shift; 150 int ret = -EINVAL; 151 int i; 152 153 for (i = 0; i < ARRAY_SIZE(hdc100x_int_time[chan]); i++) { 154 if (val2 && val2 == hdc100x_int_time[chan][i]) { 155 ret = hdc100x_update_config(data, 156 hdc100x_resolution_shift[chan].mask << shift, 157 i << shift); 158 if (!ret) 159 data->adc_int_us[chan] = val2; 160 break; 161 } 162 } 163 164 return ret; 165 } 166 167 static int hdc100x_get_measurement(struct hdc100x_data *data, 168 struct iio_chan_spec const *chan) 169 { 170 struct i2c_client *client = data->client; 171 int delay = data->adc_int_us[chan->address]; 172 int ret; 173 __be16 val; 174 175 /* start measurement */ 176 ret = i2c_smbus_write_byte(client, chan->address); 177 if (ret < 0) { 178 dev_err(&client->dev, "cannot start measurement"); 179 return ret; 180 } 181 182 /* wait for integration time to pass */ 183 usleep_range(delay, delay + 1000); 184 185 /* read measurement */ 186 ret = i2c_master_recv(data->client, (char *)&val, sizeof(val)); 187 if (ret < 0) { 188 dev_err(&client->dev, "cannot read sensor data\n"); 189 return ret; 190 } 191 return be16_to_cpu(val); 192 } 193 194 static int hdc100x_get_heater_status(struct hdc100x_data *data) 195 { 196 return !!(data->config & HDC100X_REG_CONFIG_HEATER_EN); 197 } 198 199 static int hdc100x_read_raw(struct iio_dev *indio_dev, 200 struct iio_chan_spec const *chan, int *val, 201 int *val2, long mask) 202 { 203 struct hdc100x_data *data = iio_priv(indio_dev); 204 205 switch (mask) { 206 case IIO_CHAN_INFO_RAW: { 207 int ret; 208 209 mutex_lock(&data->lock); 210 if (chan->type == IIO_CURRENT) { 211 *val = hdc100x_get_heater_status(data); 212 ret = IIO_VAL_INT; 213 } else { 214 ret = iio_device_claim_direct_mode(indio_dev); 215 if (ret) { 216 mutex_unlock(&data->lock); 217 return ret; 218 } 219 220 ret = hdc100x_get_measurement(data, chan); 221 iio_device_release_direct_mode(indio_dev); 222 if (ret >= 0) { 223 *val = ret; 224 ret = IIO_VAL_INT; 225 } 226 } 227 mutex_unlock(&data->lock); 228 return ret; 229 } 230 case IIO_CHAN_INFO_INT_TIME: 231 *val = 0; 232 *val2 = data->adc_int_us[chan->address]; 233 return IIO_VAL_INT_PLUS_MICRO; 234 case IIO_CHAN_INFO_SCALE: 235 if (chan->type == IIO_TEMP) { 236 *val = 165000; 237 *val2 = 65536; 238 return IIO_VAL_FRACTIONAL; 239 } else { 240 *val = 100; 241 *val2 = 65536; 242 return IIO_VAL_FRACTIONAL; 243 } 244 break; 245 case IIO_CHAN_INFO_OFFSET: 246 *val = -15887; 247 *val2 = 515151; 248 return IIO_VAL_INT_PLUS_MICRO; 249 default: 250 return -EINVAL; 251 } 252 } 253 254 static int hdc100x_write_raw(struct iio_dev *indio_dev, 255 struct iio_chan_spec const *chan, 256 int val, int val2, long mask) 257 { 258 struct hdc100x_data *data = iio_priv(indio_dev); 259 int ret = -EINVAL; 260 261 switch (mask) { 262 case IIO_CHAN_INFO_INT_TIME: 263 if (val != 0) 264 return -EINVAL; 265 266 mutex_lock(&data->lock); 267 ret = hdc100x_set_it_time(data, chan->address, val2); 268 mutex_unlock(&data->lock); 269 return ret; 270 case IIO_CHAN_INFO_RAW: 271 if (chan->type != IIO_CURRENT || val2 != 0) 272 return -EINVAL; 273 274 mutex_lock(&data->lock); 275 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_HEATER_EN, 276 val ? HDC100X_REG_CONFIG_HEATER_EN : 0); 277 mutex_unlock(&data->lock); 278 return ret; 279 default: 280 return -EINVAL; 281 } 282 } 283 284 static int hdc100x_buffer_postenable(struct iio_dev *indio_dev) 285 { 286 struct hdc100x_data *data = iio_priv(indio_dev); 287 int ret; 288 289 /* Buffer is enabled. First set ACQ Mode, then attach poll func */ 290 mutex_lock(&data->lock); 291 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 292 HDC100X_REG_CONFIG_ACQ_MODE); 293 mutex_unlock(&data->lock); 294 if (ret) 295 return ret; 296 297 return iio_triggered_buffer_postenable(indio_dev); 298 } 299 300 static int hdc100x_buffer_predisable(struct iio_dev *indio_dev) 301 { 302 struct hdc100x_data *data = iio_priv(indio_dev); 303 int ret; 304 305 /* First detach poll func, then reset ACQ mode. OK to disable buffer */ 306 ret = iio_triggered_buffer_predisable(indio_dev); 307 if (ret) 308 return ret; 309 310 mutex_lock(&data->lock); 311 ret = hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0); 312 mutex_unlock(&data->lock); 313 314 return ret; 315 } 316 317 static const struct iio_buffer_setup_ops hdc_buffer_setup_ops = { 318 .postenable = hdc100x_buffer_postenable, 319 .predisable = hdc100x_buffer_predisable, 320 }; 321 322 static irqreturn_t hdc100x_trigger_handler(int irq, void *p) 323 { 324 struct iio_poll_func *pf = p; 325 struct iio_dev *indio_dev = pf->indio_dev; 326 struct hdc100x_data *data = iio_priv(indio_dev); 327 struct i2c_client *client = data->client; 328 int delay = data->adc_int_us[0] + data->adc_int_us[1]; 329 int ret; 330 s16 buf[8]; /* 2x s16 + padding + 8 byte timestamp */ 331 332 /* dual read starts at temp register */ 333 mutex_lock(&data->lock); 334 ret = i2c_smbus_write_byte(client, HDC100X_REG_TEMP); 335 if (ret < 0) { 336 dev_err(&client->dev, "cannot start measurement\n"); 337 goto err; 338 } 339 usleep_range(delay, delay + 1000); 340 341 ret = i2c_master_recv(client, (u8 *)buf, 4); 342 if (ret < 0) { 343 dev_err(&client->dev, "cannot read sensor data\n"); 344 goto err; 345 } 346 347 iio_push_to_buffers_with_timestamp(indio_dev, buf, 348 iio_get_time_ns(indio_dev)); 349 err: 350 mutex_unlock(&data->lock); 351 iio_trigger_notify_done(indio_dev->trig); 352 353 return IRQ_HANDLED; 354 } 355 356 static const struct iio_info hdc100x_info = { 357 .read_raw = hdc100x_read_raw, 358 .write_raw = hdc100x_write_raw, 359 .attrs = &hdc100x_attribute_group, 360 }; 361 362 static int hdc100x_probe(struct i2c_client *client, 363 const struct i2c_device_id *id) 364 { 365 struct iio_dev *indio_dev; 366 struct hdc100x_data *data; 367 int ret; 368 369 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA | 370 I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C)) 371 return -EOPNOTSUPP; 372 373 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 374 if (!indio_dev) 375 return -ENOMEM; 376 377 data = iio_priv(indio_dev); 378 i2c_set_clientdata(client, indio_dev); 379 data->client = client; 380 mutex_init(&data->lock); 381 382 indio_dev->dev.parent = &client->dev; 383 indio_dev->name = dev_name(&client->dev); 384 indio_dev->modes = INDIO_DIRECT_MODE; 385 indio_dev->info = &hdc100x_info; 386 387 indio_dev->channels = hdc100x_channels; 388 indio_dev->num_channels = ARRAY_SIZE(hdc100x_channels); 389 indio_dev->available_scan_masks = hdc100x_scan_masks; 390 391 /* be sure we are in a known state */ 392 hdc100x_set_it_time(data, 0, hdc100x_int_time[0][0]); 393 hdc100x_set_it_time(data, 1, hdc100x_int_time[1][0]); 394 hdc100x_update_config(data, HDC100X_REG_CONFIG_ACQ_MODE, 0); 395 396 ret = iio_triggered_buffer_setup(indio_dev, NULL, 397 hdc100x_trigger_handler, 398 &hdc_buffer_setup_ops); 399 if (ret < 0) { 400 dev_err(&client->dev, "iio triggered buffer setup failed\n"); 401 return ret; 402 } 403 ret = iio_device_register(indio_dev); 404 if (ret < 0) 405 iio_triggered_buffer_cleanup(indio_dev); 406 407 return ret; 408 } 409 410 static int hdc100x_remove(struct i2c_client *client) 411 { 412 struct iio_dev *indio_dev = i2c_get_clientdata(client); 413 414 iio_device_unregister(indio_dev); 415 iio_triggered_buffer_cleanup(indio_dev); 416 417 return 0; 418 } 419 420 static const struct i2c_device_id hdc100x_id[] = { 421 { "hdc100x", 0 }, 422 { "hdc1000", 0 }, 423 { "hdc1008", 0 }, 424 { "hdc1010", 0 }, 425 { "hdc1050", 0 }, 426 { "hdc1080", 0 }, 427 { } 428 }; 429 MODULE_DEVICE_TABLE(i2c, hdc100x_id); 430 431 static const struct of_device_id hdc100x_dt_ids[] = { 432 { .compatible = "ti,hdc1000" }, 433 { .compatible = "ti,hdc1008" }, 434 { .compatible = "ti,hdc1010" }, 435 { .compatible = "ti,hdc1050" }, 436 { .compatible = "ti,hdc1080" }, 437 { } 438 }; 439 MODULE_DEVICE_TABLE(of, hdc100x_dt_ids); 440 441 static struct i2c_driver hdc100x_driver = { 442 .driver = { 443 .name = "hdc100x", 444 .of_match_table = of_match_ptr(hdc100x_dt_ids), 445 }, 446 .probe = hdc100x_probe, 447 .remove = hdc100x_remove, 448 .id_table = hdc100x_id, 449 }; 450 module_i2c_driver(hdc100x_driver); 451 452 MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>"); 453 MODULE_DESCRIPTION("TI HDC100x humidity and temperature sensor driver"); 454 MODULE_LICENSE("GPL"); 455