David Frey | 7c84f7f | 2016-06-02 09:59:11 +0200 | [diff] [blame] | 1 | /* Sensirion SHT3x-DIS humidity and temperature sensor driver. |
| 2 | * The SHT3x comes in many different versions, this driver is for the |
| 3 | * I2C version only. |
| 4 | * |
| 5 | * Copyright (C) 2016 Sensirion AG, Switzerland |
| 6 | * Author: David Frey <david.frey@sensirion.com> |
| 7 | * Author: Pascal Sachs <pascal.sachs@sensirion.com> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License as published by |
| 11 | * the Free Software Foundation; either version 2 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | */ |
| 20 | |
| 21 | #include <asm/page.h> |
| 22 | #include <linux/crc8.h> |
| 23 | #include <linux/delay.h> |
| 24 | #include <linux/err.h> |
| 25 | #include <linux/hwmon.h> |
| 26 | #include <linux/hwmon-sysfs.h> |
| 27 | #include <linux/i2c.h> |
| 28 | #include <linux/init.h> |
| 29 | #include <linux/kernel.h> |
| 30 | #include <linux/module.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/jiffies.h> |
| 33 | #include <linux/platform_data/sht3x.h> |
| 34 | |
| 35 | /* commands (high precision mode) */ |
| 36 | static const unsigned char sht3x_cmd_measure_blocking_hpm[] = { 0x2c, 0x06 }; |
| 37 | static const unsigned char sht3x_cmd_measure_nonblocking_hpm[] = { 0x24, 0x00 }; |
| 38 | |
| 39 | /* commands (low power mode) */ |
| 40 | static const unsigned char sht3x_cmd_measure_blocking_lpm[] = { 0x2c, 0x10 }; |
| 41 | static const unsigned char sht3x_cmd_measure_nonblocking_lpm[] = { 0x24, 0x16 }; |
| 42 | |
| 43 | /* commands for periodic mode */ |
| 44 | static const unsigned char sht3x_cmd_measure_periodic_mode[] = { 0xe0, 0x00 }; |
| 45 | static const unsigned char sht3x_cmd_break[] = { 0x30, 0x93 }; |
| 46 | |
Matt Ranostay | 50c22cd | 2016-07-09 23:49:18 -0700 | [diff] [blame] | 47 | /* commands for heater control */ |
| 48 | static const unsigned char sht3x_cmd_heater_on[] = { 0x30, 0x6d }; |
| 49 | static const unsigned char sht3x_cmd_heater_off[] = { 0x30, 0x66 }; |
| 50 | |
David Frey | 7c84f7f | 2016-06-02 09:59:11 +0200 | [diff] [blame] | 51 | /* other commands */ |
| 52 | static const unsigned char sht3x_cmd_read_status_reg[] = { 0xf3, 0x2d }; |
| 53 | static const unsigned char sht3x_cmd_clear_status_reg[] = { 0x30, 0x41 }; |
| 54 | |
| 55 | /* delays for non-blocking i2c commands, both in us */ |
| 56 | #define SHT3X_NONBLOCKING_WAIT_TIME_HPM 15000 |
| 57 | #define SHT3X_NONBLOCKING_WAIT_TIME_LPM 4000 |
| 58 | |
| 59 | #define SHT3X_WORD_LEN 2 |
| 60 | #define SHT3X_CMD_LENGTH 2 |
| 61 | #define SHT3X_CRC8_LEN 1 |
| 62 | #define SHT3X_RESPONSE_LENGTH 6 |
| 63 | #define SHT3X_CRC8_POLYNOMIAL 0x31 |
| 64 | #define SHT3X_CRC8_INIT 0xFF |
| 65 | #define SHT3X_MIN_TEMPERATURE -45000 |
| 66 | #define SHT3X_MAX_TEMPERATURE 130000 |
| 67 | #define SHT3X_MIN_HUMIDITY 0 |
| 68 | #define SHT3X_MAX_HUMIDITY 100000 |
| 69 | |
| 70 | enum sht3x_chips { |
| 71 | sht3x, |
| 72 | sts3x, |
| 73 | }; |
| 74 | |
| 75 | enum sht3x_limits { |
| 76 | limit_max = 0, |
| 77 | limit_max_hyst, |
| 78 | limit_min, |
| 79 | limit_min_hyst, |
| 80 | }; |
| 81 | |
| 82 | DECLARE_CRC8_TABLE(sht3x_crc8_table); |
| 83 | |
| 84 | /* periodic measure commands (high precision mode) */ |
| 85 | static const char periodic_measure_commands_hpm[][SHT3X_CMD_LENGTH] = { |
| 86 | /* 0.5 measurements per second */ |
| 87 | {0x20, 0x32}, |
| 88 | /* 1 measurements per second */ |
| 89 | {0x21, 0x30}, |
| 90 | /* 2 measurements per second */ |
| 91 | {0x22, 0x36}, |
| 92 | /* 4 measurements per second */ |
| 93 | {0x23, 0x34}, |
| 94 | /* 10 measurements per second */ |
| 95 | {0x27, 0x37}, |
| 96 | }; |
| 97 | |
| 98 | /* periodic measure commands (low power mode) */ |
| 99 | static const char periodic_measure_commands_lpm[][SHT3X_CMD_LENGTH] = { |
| 100 | /* 0.5 measurements per second */ |
| 101 | {0x20, 0x2f}, |
| 102 | /* 1 measurements per second */ |
| 103 | {0x21, 0x2d}, |
| 104 | /* 2 measurements per second */ |
| 105 | {0x22, 0x2b}, |
| 106 | /* 4 measurements per second */ |
| 107 | {0x23, 0x29}, |
| 108 | /* 10 measurements per second */ |
| 109 | {0x27, 0x2a}, |
| 110 | }; |
| 111 | |
| 112 | struct sht3x_limit_commands { |
| 113 | const char read_command[SHT3X_CMD_LENGTH]; |
| 114 | const char write_command[SHT3X_CMD_LENGTH]; |
| 115 | }; |
| 116 | |
| 117 | static const struct sht3x_limit_commands limit_commands[] = { |
| 118 | /* temp1_max, humidity1_max */ |
| 119 | [limit_max] = { {0xe1, 0x1f}, {0x61, 0x1d} }, |
| 120 | /* temp_1_max_hyst, humidity1_max_hyst */ |
| 121 | [limit_max_hyst] = { {0xe1, 0x14}, {0x61, 0x16} }, |
| 122 | /* temp1_min, humidity1_min */ |
| 123 | [limit_min] = { {0xe1, 0x02}, {0x61, 0x00} }, |
| 124 | /* temp_1_min_hyst, humidity1_min_hyst */ |
| 125 | [limit_min_hyst] = { {0xe1, 0x09}, {0x61, 0x0B} }, |
| 126 | }; |
| 127 | |
| 128 | #define SHT3X_NUM_LIMIT_CMD ARRAY_SIZE(limit_commands) |
| 129 | |
| 130 | static const u16 mode_to_update_interval[] = { |
| 131 | 0, |
| 132 | 2000, |
| 133 | 1000, |
| 134 | 500, |
| 135 | 250, |
| 136 | 100, |
| 137 | }; |
| 138 | |
| 139 | struct sht3x_data { |
| 140 | struct i2c_client *client; |
| 141 | struct mutex i2c_lock; /* lock for sending i2c commands */ |
| 142 | struct mutex data_lock; /* lock for updating driver data */ |
| 143 | |
| 144 | u8 mode; |
| 145 | const unsigned char *command; |
| 146 | u32 wait_time; /* in us*/ |
| 147 | unsigned long last_update; /* last update in periodic mode*/ |
| 148 | |
| 149 | struct sht3x_platform_data setup; |
| 150 | |
| 151 | /* |
| 152 | * cached values for temperature and humidity and limits |
| 153 | * the limits arrays have the following order: |
| 154 | * max, max_hyst, min, min_hyst |
| 155 | */ |
| 156 | int temperature; |
| 157 | int temperature_limits[SHT3X_NUM_LIMIT_CMD]; |
| 158 | u32 humidity; |
| 159 | u32 humidity_limits[SHT3X_NUM_LIMIT_CMD]; |
| 160 | }; |
| 161 | |
| 162 | static u8 get_mode_from_update_interval(u16 value) |
| 163 | { |
| 164 | size_t index; |
| 165 | u8 number_of_modes = ARRAY_SIZE(mode_to_update_interval); |
| 166 | |
| 167 | if (value == 0) |
| 168 | return 0; |
| 169 | |
| 170 | /* find next faster update interval */ |
| 171 | for (index = 1; index < number_of_modes; index++) { |
| 172 | if (mode_to_update_interval[index] <= value) |
| 173 | return index; |
| 174 | } |
| 175 | |
| 176 | return number_of_modes - 1; |
| 177 | } |
| 178 | |
| 179 | static int sht3x_read_from_command(struct i2c_client *client, |
| 180 | struct sht3x_data *data, |
| 181 | const char *command, |
| 182 | char *buf, int length, u32 wait_time) |
| 183 | { |
| 184 | int ret; |
| 185 | |
| 186 | mutex_lock(&data->i2c_lock); |
| 187 | ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH); |
| 188 | |
| 189 | if (ret != SHT3X_CMD_LENGTH) { |
| 190 | ret = ret < 0 ? ret : -EIO; |
| 191 | goto out; |
| 192 | } |
| 193 | |
| 194 | if (wait_time) |
| 195 | usleep_range(wait_time, wait_time + 1000); |
| 196 | |
| 197 | ret = i2c_master_recv(client, buf, length); |
| 198 | if (ret != length) { |
| 199 | ret = ret < 0 ? ret : -EIO; |
| 200 | goto out; |
| 201 | } |
| 202 | |
| 203 | ret = 0; |
| 204 | out: |
| 205 | mutex_unlock(&data->i2c_lock); |
| 206 | return ret; |
| 207 | } |
| 208 | |
| 209 | static int sht3x_extract_temperature(u16 raw) |
| 210 | { |
| 211 | /* |
| 212 | * From datasheet: |
| 213 | * T = -45 + 175 * ST / 2^16 |
| 214 | * Adapted for integer fixed point (3 digit) arithmetic. |
| 215 | */ |
| 216 | return ((21875 * (int)raw) >> 13) - 45000; |
| 217 | } |
| 218 | |
| 219 | static u32 sht3x_extract_humidity(u16 raw) |
| 220 | { |
| 221 | /* |
| 222 | * From datasheet: |
| 223 | * RH = 100 * SRH / 2^16 |
| 224 | * Adapted for integer fixed point (3 digit) arithmetic. |
| 225 | */ |
| 226 | return (12500 * (u32)raw) >> 13; |
| 227 | } |
| 228 | |
| 229 | static struct sht3x_data *sht3x_update_client(struct device *dev) |
| 230 | { |
| 231 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 232 | struct i2c_client *client = data->client; |
| 233 | u16 interval_ms = mode_to_update_interval[data->mode]; |
| 234 | unsigned long interval_jiffies = msecs_to_jiffies(interval_ms); |
| 235 | unsigned char buf[SHT3X_RESPONSE_LENGTH]; |
| 236 | u16 val; |
| 237 | int ret = 0; |
| 238 | |
| 239 | mutex_lock(&data->data_lock); |
| 240 | /* |
| 241 | * Only update cached readings once per update interval in periodic |
| 242 | * mode. In single shot mode the sensor measures values on demand, so |
| 243 | * every time the sysfs interface is called, a measurement is triggered. |
| 244 | * In periodic mode however, the measurement process is handled |
| 245 | * internally by the sensor and reading out sensor values only makes |
| 246 | * sense if a new reading is available. |
| 247 | */ |
| 248 | if (time_after(jiffies, data->last_update + interval_jiffies)) { |
| 249 | ret = sht3x_read_from_command(client, data, data->command, buf, |
| 250 | sizeof(buf), data->wait_time); |
| 251 | if (ret) |
| 252 | goto out; |
| 253 | |
| 254 | val = be16_to_cpup((__be16 *)buf); |
| 255 | data->temperature = sht3x_extract_temperature(val); |
| 256 | val = be16_to_cpup((__be16 *)(buf + 3)); |
| 257 | data->humidity = sht3x_extract_humidity(val); |
| 258 | data->last_update = jiffies; |
| 259 | } |
| 260 | |
| 261 | out: |
| 262 | mutex_unlock(&data->data_lock); |
| 263 | if (ret) |
| 264 | return ERR_PTR(ret); |
| 265 | |
| 266 | return data; |
| 267 | } |
| 268 | |
| 269 | /* sysfs attributes */ |
| 270 | static ssize_t temp1_input_show(struct device *dev, |
| 271 | struct device_attribute *attr, char *buf) |
| 272 | { |
| 273 | struct sht3x_data *data = sht3x_update_client(dev); |
| 274 | |
| 275 | if (IS_ERR(data)) |
| 276 | return PTR_ERR(data); |
| 277 | |
| 278 | return sprintf(buf, "%d\n", data->temperature); |
| 279 | } |
| 280 | |
| 281 | static ssize_t humidity1_input_show(struct device *dev, |
| 282 | struct device_attribute *attr, char *buf) |
| 283 | { |
| 284 | struct sht3x_data *data = sht3x_update_client(dev); |
| 285 | |
| 286 | if (IS_ERR(data)) |
| 287 | return PTR_ERR(data); |
| 288 | |
| 289 | return sprintf(buf, "%u\n", data->humidity); |
| 290 | } |
| 291 | |
| 292 | /* |
| 293 | * limits_update must only be called from probe or with data_lock held |
| 294 | */ |
| 295 | static int limits_update(struct sht3x_data *data) |
| 296 | { |
| 297 | int ret; |
| 298 | u8 index; |
| 299 | int temperature; |
| 300 | u32 humidity; |
| 301 | u16 raw; |
| 302 | char buffer[SHT3X_RESPONSE_LENGTH]; |
| 303 | const struct sht3x_limit_commands *commands; |
| 304 | struct i2c_client *client = data->client; |
| 305 | |
| 306 | for (index = 0; index < SHT3X_NUM_LIMIT_CMD; index++) { |
| 307 | commands = &limit_commands[index]; |
| 308 | ret = sht3x_read_from_command(client, data, |
| 309 | commands->read_command, buffer, |
| 310 | SHT3X_RESPONSE_LENGTH, 0); |
| 311 | |
| 312 | if (ret) |
| 313 | return ret; |
| 314 | |
| 315 | raw = be16_to_cpup((__be16 *)buffer); |
| 316 | temperature = sht3x_extract_temperature((raw & 0x01ff) << 7); |
| 317 | humidity = sht3x_extract_humidity(raw & 0xfe00); |
| 318 | data->temperature_limits[index] = temperature; |
| 319 | data->humidity_limits[index] = humidity; |
| 320 | } |
| 321 | |
| 322 | return ret; |
| 323 | } |
| 324 | |
| 325 | static ssize_t temp1_limit_show(struct device *dev, |
| 326 | struct device_attribute *attr, |
| 327 | char *buf) |
| 328 | { |
| 329 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 330 | u8 index = to_sensor_dev_attr(attr)->index; |
| 331 | int temperature_limit = data->temperature_limits[index]; |
| 332 | |
| 333 | return scnprintf(buf, PAGE_SIZE, "%d\n", temperature_limit); |
| 334 | } |
| 335 | |
| 336 | static ssize_t humidity1_limit_show(struct device *dev, |
| 337 | struct device_attribute *attr, |
| 338 | char *buf) |
| 339 | { |
| 340 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 341 | u8 index = to_sensor_dev_attr(attr)->index; |
| 342 | u32 humidity_limit = data->humidity_limits[index]; |
| 343 | |
| 344 | return scnprintf(buf, PAGE_SIZE, "%u\n", humidity_limit); |
| 345 | } |
| 346 | |
| 347 | /* |
| 348 | * limit_store must only be called with data_lock held |
| 349 | */ |
| 350 | static size_t limit_store(struct device *dev, |
| 351 | size_t count, |
| 352 | u8 index, |
| 353 | int temperature, |
| 354 | u32 humidity) |
| 355 | { |
| 356 | char buffer[SHT3X_CMD_LENGTH + SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; |
| 357 | char *position = buffer; |
| 358 | int ret; |
| 359 | u16 raw; |
| 360 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 361 | struct i2c_client *client = data->client; |
| 362 | const struct sht3x_limit_commands *commands; |
| 363 | |
| 364 | commands = &limit_commands[index]; |
| 365 | |
| 366 | memcpy(position, commands->write_command, SHT3X_CMD_LENGTH); |
| 367 | position += SHT3X_CMD_LENGTH; |
| 368 | /* |
| 369 | * ST = (T + 45) / 175 * 2^16 |
| 370 | * SRH = RH / 100 * 2^16 |
| 371 | * adapted for fixed point arithmetic and packed the same as |
| 372 | * in limit_show() |
| 373 | */ |
| 374 | raw = ((u32)(temperature + 45000) * 24543) >> (16 + 7); |
| 375 | raw |= ((humidity * 42950) >> 16) & 0xfe00; |
| 376 | |
| 377 | *((__be16 *)position) = cpu_to_be16(raw); |
| 378 | position += SHT3X_WORD_LEN; |
| 379 | *position = crc8(sht3x_crc8_table, |
| 380 | position - SHT3X_WORD_LEN, |
| 381 | SHT3X_WORD_LEN, |
| 382 | SHT3X_CRC8_INIT); |
| 383 | |
| 384 | mutex_lock(&data->i2c_lock); |
| 385 | ret = i2c_master_send(client, buffer, sizeof(buffer)); |
| 386 | mutex_unlock(&data->i2c_lock); |
| 387 | |
| 388 | if (ret != sizeof(buffer)) |
| 389 | return ret < 0 ? ret : -EIO; |
| 390 | |
| 391 | data->temperature_limits[index] = temperature; |
| 392 | data->humidity_limits[index] = humidity; |
| 393 | return count; |
| 394 | } |
| 395 | |
| 396 | static ssize_t temp1_limit_store(struct device *dev, |
| 397 | struct device_attribute *attr, |
| 398 | const char *buf, |
| 399 | size_t count) |
| 400 | { |
| 401 | int temperature; |
| 402 | int ret; |
| 403 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 404 | u8 index = to_sensor_dev_attr(attr)->index; |
| 405 | |
| 406 | ret = kstrtoint(buf, 0, &temperature); |
| 407 | if (ret) |
| 408 | return ret; |
| 409 | |
| 410 | temperature = clamp_val(temperature, SHT3X_MIN_TEMPERATURE, |
| 411 | SHT3X_MAX_TEMPERATURE); |
| 412 | mutex_lock(&data->data_lock); |
| 413 | ret = limit_store(dev, count, index, temperature, |
| 414 | data->humidity_limits[index]); |
| 415 | mutex_unlock(&data->data_lock); |
| 416 | |
| 417 | return ret; |
| 418 | } |
| 419 | |
| 420 | static ssize_t humidity1_limit_store(struct device *dev, |
| 421 | struct device_attribute *attr, |
| 422 | const char *buf, |
| 423 | size_t count) |
| 424 | { |
| 425 | u32 humidity; |
| 426 | int ret; |
| 427 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 428 | u8 index = to_sensor_dev_attr(attr)->index; |
| 429 | |
| 430 | ret = kstrtou32(buf, 0, &humidity); |
| 431 | if (ret) |
| 432 | return ret; |
| 433 | |
| 434 | humidity = clamp_val(humidity, SHT3X_MIN_HUMIDITY, SHT3X_MAX_HUMIDITY); |
| 435 | mutex_lock(&data->data_lock); |
| 436 | ret = limit_store(dev, count, index, data->temperature_limits[index], |
| 437 | humidity); |
| 438 | mutex_unlock(&data->data_lock); |
| 439 | |
| 440 | return ret; |
| 441 | } |
| 442 | |
| 443 | static void sht3x_select_command(struct sht3x_data *data) |
| 444 | { |
| 445 | /* |
| 446 | * In blocking mode (clock stretching mode) the I2C bus |
| 447 | * is blocked for other traffic, thus the call to i2c_master_recv() |
| 448 | * will wait until the data is ready. For non blocking mode, we |
| 449 | * have to wait ourselves. |
| 450 | */ |
| 451 | if (data->mode > 0) { |
| 452 | data->command = sht3x_cmd_measure_periodic_mode; |
| 453 | data->wait_time = 0; |
| 454 | } else if (data->setup.blocking_io) { |
| 455 | data->command = data->setup.high_precision ? |
| 456 | sht3x_cmd_measure_blocking_hpm : |
| 457 | sht3x_cmd_measure_blocking_lpm; |
| 458 | data->wait_time = 0; |
| 459 | } else { |
| 460 | if (data->setup.high_precision) { |
| 461 | data->command = sht3x_cmd_measure_nonblocking_hpm; |
| 462 | data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_HPM; |
| 463 | } else { |
| 464 | data->command = sht3x_cmd_measure_nonblocking_lpm; |
| 465 | data->wait_time = SHT3X_NONBLOCKING_WAIT_TIME_LPM; |
| 466 | } |
| 467 | } |
| 468 | } |
| 469 | |
| 470 | static int status_register_read(struct device *dev, |
| 471 | struct device_attribute *attr, |
| 472 | char *buffer, int length) |
| 473 | { |
| 474 | int ret; |
| 475 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 476 | struct i2c_client *client = data->client; |
| 477 | |
| 478 | ret = sht3x_read_from_command(client, data, sht3x_cmd_read_status_reg, |
| 479 | buffer, length, 0); |
| 480 | |
| 481 | return ret; |
| 482 | } |
| 483 | |
| 484 | static ssize_t temp1_alarm_show(struct device *dev, |
| 485 | struct device_attribute *attr, |
| 486 | char *buf) |
| 487 | { |
| 488 | char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; |
| 489 | int ret; |
| 490 | |
| 491 | ret = status_register_read(dev, attr, buffer, |
| 492 | SHT3X_WORD_LEN + SHT3X_CRC8_LEN); |
| 493 | if (ret) |
| 494 | return ret; |
| 495 | |
| 496 | return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x04)); |
| 497 | } |
| 498 | |
| 499 | static ssize_t humidity1_alarm_show(struct device *dev, |
| 500 | struct device_attribute *attr, |
| 501 | char *buf) |
| 502 | { |
| 503 | char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; |
| 504 | int ret; |
| 505 | |
| 506 | ret = status_register_read(dev, attr, buffer, |
| 507 | SHT3X_WORD_LEN + SHT3X_CRC8_LEN); |
| 508 | if (ret) |
| 509 | return ret; |
| 510 | |
| 511 | return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x08)); |
| 512 | } |
| 513 | |
Matt Ranostay | 50c22cd | 2016-07-09 23:49:18 -0700 | [diff] [blame] | 514 | static ssize_t heater_enable_show(struct device *dev, |
| 515 | struct device_attribute *attr, |
| 516 | char *buf) |
| 517 | { |
| 518 | char buffer[SHT3X_WORD_LEN + SHT3X_CRC8_LEN]; |
| 519 | int ret; |
| 520 | |
| 521 | ret = status_register_read(dev, attr, buffer, |
| 522 | SHT3X_WORD_LEN + SHT3X_CRC8_LEN); |
| 523 | if (ret) |
| 524 | return ret; |
| 525 | |
| 526 | return scnprintf(buf, PAGE_SIZE, "%d\n", !!(buffer[0] & 0x20)); |
| 527 | } |
| 528 | |
| 529 | static ssize_t heater_enable_store(struct device *dev, |
| 530 | struct device_attribute *attr, |
| 531 | const char *buf, |
| 532 | size_t count) |
| 533 | { |
| 534 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 535 | struct i2c_client *client = data->client; |
| 536 | int ret; |
| 537 | bool status; |
| 538 | |
| 539 | ret = kstrtobool(buf, &status); |
| 540 | if (ret) |
| 541 | return ret; |
| 542 | |
| 543 | mutex_lock(&data->i2c_lock); |
| 544 | |
| 545 | if (status) |
| 546 | ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_on, |
| 547 | SHT3X_CMD_LENGTH); |
| 548 | else |
| 549 | ret = i2c_master_send(client, (char *)&sht3x_cmd_heater_off, |
| 550 | SHT3X_CMD_LENGTH); |
| 551 | |
| 552 | mutex_unlock(&data->i2c_lock); |
| 553 | |
| 554 | return ret; |
| 555 | } |
| 556 | |
David Frey | 7c84f7f | 2016-06-02 09:59:11 +0200 | [diff] [blame] | 557 | static ssize_t update_interval_show(struct device *dev, |
| 558 | struct device_attribute *attr, |
| 559 | char *buf) |
| 560 | { |
| 561 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 562 | |
| 563 | return scnprintf(buf, PAGE_SIZE, "%u\n", |
| 564 | mode_to_update_interval[data->mode]); |
| 565 | } |
| 566 | |
| 567 | static ssize_t update_interval_store(struct device *dev, |
| 568 | struct device_attribute *attr, |
| 569 | const char *buf, |
| 570 | size_t count) |
| 571 | { |
| 572 | u16 update_interval; |
| 573 | u8 mode; |
| 574 | int ret; |
| 575 | const char *command; |
| 576 | struct sht3x_data *data = dev_get_drvdata(dev); |
| 577 | struct i2c_client *client = data->client; |
| 578 | |
| 579 | ret = kstrtou16(buf, 0, &update_interval); |
| 580 | if (ret) |
| 581 | return ret; |
| 582 | |
| 583 | mode = get_mode_from_update_interval(update_interval); |
| 584 | |
| 585 | mutex_lock(&data->data_lock); |
| 586 | /* mode did not change */ |
| 587 | if (mode == data->mode) { |
| 588 | mutex_unlock(&data->data_lock); |
| 589 | return count; |
| 590 | } |
| 591 | |
| 592 | mutex_lock(&data->i2c_lock); |
| 593 | /* |
| 594 | * Abort periodic measure mode. |
| 595 | * To do any changes to the configuration while in periodic mode, we |
| 596 | * have to send a break command to the sensor, which then falls back |
| 597 | * to single shot (mode = 0). |
| 598 | */ |
| 599 | if (data->mode > 0) { |
| 600 | ret = i2c_master_send(client, sht3x_cmd_break, |
| 601 | SHT3X_CMD_LENGTH); |
| 602 | if (ret != SHT3X_CMD_LENGTH) |
| 603 | goto out; |
| 604 | data->mode = 0; |
| 605 | } |
| 606 | |
| 607 | if (mode > 0) { |
| 608 | if (data->setup.high_precision) |
| 609 | command = periodic_measure_commands_hpm[mode - 1]; |
| 610 | else |
| 611 | command = periodic_measure_commands_lpm[mode - 1]; |
| 612 | |
| 613 | /* select mode */ |
| 614 | ret = i2c_master_send(client, command, SHT3X_CMD_LENGTH); |
| 615 | if (ret != SHT3X_CMD_LENGTH) |
| 616 | goto out; |
| 617 | } |
| 618 | |
| 619 | /* select mode and command */ |
| 620 | data->mode = mode; |
| 621 | sht3x_select_command(data); |
| 622 | |
| 623 | out: |
| 624 | mutex_unlock(&data->i2c_lock); |
| 625 | mutex_unlock(&data->data_lock); |
| 626 | if (ret != SHT3X_CMD_LENGTH) |
| 627 | return ret < 0 ? ret : -EIO; |
| 628 | |
| 629 | return count; |
| 630 | } |
| 631 | |
| 632 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, temp1_input_show, NULL, 0); |
| 633 | static SENSOR_DEVICE_ATTR(humidity1_input, S_IRUGO, humidity1_input_show, |
| 634 | NULL, 0); |
| 635 | static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, |
| 636 | temp1_limit_show, temp1_limit_store, |
| 637 | limit_max); |
| 638 | static SENSOR_DEVICE_ATTR(humidity1_max, S_IRUGO | S_IWUSR, |
| 639 | humidity1_limit_show, humidity1_limit_store, |
| 640 | limit_max); |
| 641 | static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR, |
| 642 | temp1_limit_show, temp1_limit_store, |
| 643 | limit_max_hyst); |
| 644 | static SENSOR_DEVICE_ATTR(humidity1_max_hyst, S_IRUGO | S_IWUSR, |
| 645 | humidity1_limit_show, humidity1_limit_store, |
| 646 | limit_max_hyst); |
| 647 | static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, |
| 648 | temp1_limit_show, temp1_limit_store, |
| 649 | limit_min); |
| 650 | static SENSOR_DEVICE_ATTR(humidity1_min, S_IRUGO | S_IWUSR, |
| 651 | humidity1_limit_show, humidity1_limit_store, |
| 652 | limit_min); |
| 653 | static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO | S_IWUSR, |
| 654 | temp1_limit_show, temp1_limit_store, |
| 655 | limit_min_hyst); |
| 656 | static SENSOR_DEVICE_ATTR(humidity1_min_hyst, S_IRUGO | S_IWUSR, |
| 657 | humidity1_limit_show, humidity1_limit_store, |
| 658 | limit_min_hyst); |
| 659 | static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, temp1_alarm_show, NULL, 0); |
| 660 | static SENSOR_DEVICE_ATTR(humidity1_alarm, S_IRUGO, humidity1_alarm_show, |
| 661 | NULL, 0); |
Matt Ranostay | 50c22cd | 2016-07-09 23:49:18 -0700 | [diff] [blame] | 662 | static SENSOR_DEVICE_ATTR(heater_enable, S_IRUGO | S_IWUSR, |
| 663 | heater_enable_show, heater_enable_store, 0); |
David Frey | 7c84f7f | 2016-06-02 09:59:11 +0200 | [diff] [blame] | 664 | static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR, |
| 665 | update_interval_show, update_interval_store, 0); |
| 666 | |
| 667 | static struct attribute *sht3x_attrs[] = { |
| 668 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
| 669 | &sensor_dev_attr_humidity1_input.dev_attr.attr, |
| 670 | &sensor_dev_attr_temp1_max.dev_attr.attr, |
| 671 | &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, |
| 672 | &sensor_dev_attr_humidity1_max.dev_attr.attr, |
| 673 | &sensor_dev_attr_humidity1_max_hyst.dev_attr.attr, |
| 674 | &sensor_dev_attr_temp1_min.dev_attr.attr, |
| 675 | &sensor_dev_attr_temp1_min_hyst.dev_attr.attr, |
| 676 | &sensor_dev_attr_humidity1_min.dev_attr.attr, |
| 677 | &sensor_dev_attr_humidity1_min_hyst.dev_attr.attr, |
| 678 | &sensor_dev_attr_temp1_alarm.dev_attr.attr, |
| 679 | &sensor_dev_attr_humidity1_alarm.dev_attr.attr, |
Matt Ranostay | 50c22cd | 2016-07-09 23:49:18 -0700 | [diff] [blame] | 680 | &sensor_dev_attr_heater_enable.dev_attr.attr, |
David Frey | 7c84f7f | 2016-06-02 09:59:11 +0200 | [diff] [blame] | 681 | &sensor_dev_attr_update_interval.dev_attr.attr, |
| 682 | NULL |
| 683 | }; |
| 684 | |
| 685 | static struct attribute *sts3x_attrs[] = { |
| 686 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
| 687 | NULL |
| 688 | }; |
| 689 | |
| 690 | ATTRIBUTE_GROUPS(sht3x); |
| 691 | ATTRIBUTE_GROUPS(sts3x); |
| 692 | |
| 693 | static int sht3x_probe(struct i2c_client *client, |
| 694 | const struct i2c_device_id *id) |
| 695 | { |
| 696 | int ret; |
| 697 | struct sht3x_data *data; |
| 698 | struct device *hwmon_dev; |
| 699 | struct i2c_adapter *adap = client->adapter; |
| 700 | struct device *dev = &client->dev; |
| 701 | const struct attribute_group **attribute_groups; |
| 702 | |
| 703 | /* |
| 704 | * we require full i2c support since the sht3x uses multi-byte read and |
| 705 | * writes as well as multi-byte commands which are not supported by |
| 706 | * the smbus protocol |
| 707 | */ |
| 708 | if (!i2c_check_functionality(adap, I2C_FUNC_I2C)) |
| 709 | return -ENODEV; |
| 710 | |
| 711 | ret = i2c_master_send(client, sht3x_cmd_clear_status_reg, |
| 712 | SHT3X_CMD_LENGTH); |
| 713 | if (ret != SHT3X_CMD_LENGTH) |
| 714 | return ret < 0 ? ret : -ENODEV; |
| 715 | |
| 716 | data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); |
| 717 | if (!data) |
| 718 | return -ENOMEM; |
| 719 | |
| 720 | data->setup.blocking_io = false; |
| 721 | data->setup.high_precision = true; |
| 722 | data->mode = 0; |
| 723 | data->last_update = 0; |
| 724 | data->client = client; |
| 725 | crc8_populate_msb(sht3x_crc8_table, SHT3X_CRC8_POLYNOMIAL); |
| 726 | |
| 727 | if (client->dev.platform_data) |
| 728 | data->setup = *(struct sht3x_platform_data *)dev->platform_data; |
| 729 | |
| 730 | sht3x_select_command(data); |
| 731 | |
| 732 | mutex_init(&data->i2c_lock); |
| 733 | mutex_init(&data->data_lock); |
| 734 | |
| 735 | ret = limits_update(data); |
| 736 | if (ret) |
| 737 | return ret; |
| 738 | |
| 739 | if (id->driver_data == sts3x) |
| 740 | attribute_groups = sts3x_groups; |
| 741 | else |
| 742 | attribute_groups = sht3x_groups; |
| 743 | |
| 744 | hwmon_dev = devm_hwmon_device_register_with_groups(dev, |
| 745 | client->name, |
| 746 | data, |
| 747 | attribute_groups); |
| 748 | |
| 749 | if (IS_ERR(hwmon_dev)) |
| 750 | dev_dbg(dev, "unable to register hwmon device\n"); |
| 751 | |
| 752 | return PTR_ERR_OR_ZERO(hwmon_dev); |
| 753 | } |
| 754 | |
| 755 | /* device ID table */ |
| 756 | static const struct i2c_device_id sht3x_ids[] = { |
| 757 | {"sht3x", sht3x}, |
| 758 | {"sts3x", sts3x}, |
| 759 | {} |
| 760 | }; |
| 761 | |
| 762 | MODULE_DEVICE_TABLE(i2c, sht3x_ids); |
| 763 | |
| 764 | static struct i2c_driver sht3x_i2c_driver = { |
| 765 | .driver.name = "sht3x", |
| 766 | .probe = sht3x_probe, |
| 767 | .id_table = sht3x_ids, |
| 768 | }; |
| 769 | |
| 770 | module_i2c_driver(sht3x_i2c_driver); |
| 771 | |
| 772 | MODULE_AUTHOR("David Frey <david.frey@sensirion.com>"); |
| 773 | MODULE_AUTHOR("Pascal Sachs <pascal.sachs@sensirion.com>"); |
| 774 | MODULE_DESCRIPTION("Sensirion SHT3x humidity and temperature sensor driver"); |
| 775 | MODULE_LICENSE("GPL"); |