1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * MS5611 pressure and temperature sensor driver 4 * 5 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com> 6 * 7 * Data sheet: 8 * http://www.meas-spec.com/downloads/MS5611-01BA03.pdf 9 * http://www.meas-spec.com/downloads/MS5607-02BA03.pdf 10 * 11 */ 12 13 #include <linux/module.h> 14 #include <linux/iio/iio.h> 15 #include <linux/delay.h> 16 #include <linux/regulator/consumer.h> 17 18 #include <linux/iio/sysfs.h> 19 #include <linux/iio/buffer.h> 20 #include <linux/iio/triggered_buffer.h> 21 #include <linux/iio/trigger_consumer.h> 22 #include "ms5611.h" 23 24 #define MS5611_INIT_OSR(_cmd, _conv_usec, _rate) \ 25 { .cmd = _cmd, .conv_usec = _conv_usec, .rate = _rate } 26 27 static const struct ms5611_osr ms5611_avail_pressure_osr[] = { 28 MS5611_INIT_OSR(0x40, 600, 256), 29 MS5611_INIT_OSR(0x42, 1170, 512), 30 MS5611_INIT_OSR(0x44, 2280, 1024), 31 MS5611_INIT_OSR(0x46, 4540, 2048), 32 MS5611_INIT_OSR(0x48, 9040, 4096) 33 }; 34 35 static const struct ms5611_osr ms5611_avail_temp_osr[] = { 36 MS5611_INIT_OSR(0x50, 600, 256), 37 MS5611_INIT_OSR(0x52, 1170, 512), 38 MS5611_INIT_OSR(0x54, 2280, 1024), 39 MS5611_INIT_OSR(0x56, 4540, 2048), 40 MS5611_INIT_OSR(0x58, 9040, 4096) 41 }; 42 43 static const char ms5611_show_osr[] = "256 512 1024 2048 4096"; 44 45 static IIO_CONST_ATTR(oversampling_ratio_available, ms5611_show_osr); 46 47 static struct attribute *ms5611_attributes[] = { 48 &iio_const_attr_oversampling_ratio_available.dev_attr.attr, 49 NULL, 50 }; 51 52 static const struct attribute_group ms5611_attribute_group = { 53 .attrs = ms5611_attributes, 54 }; 55 56 static bool ms5611_prom_is_valid(u16 *prom, size_t len) 57 { 58 int i, j; 59 uint16_t crc = 0, crc_orig = prom[7] & 0x000F; 60 61 prom[7] &= 0xFF00; 62 63 for (i = 0; i < len * 2; i++) { 64 if (i % 2 == 1) 65 crc ^= prom[i >> 1] & 0x00FF; 66 else 67 crc ^= prom[i >> 1] >> 8; 68 69 for (j = 0; j < 8; j++) { 70 if (crc & 0x8000) 71 crc = (crc << 1) ^ 0x3000; 72 else 73 crc <<= 1; 74 } 75 } 76 77 crc = (crc >> 12) & 0x000F; 78 79 return crc_orig != 0x0000 && crc == crc_orig; 80 } 81 82 static int ms5611_read_prom(struct iio_dev *indio_dev) 83 { 84 int ret, i; 85 struct ms5611_state *st = iio_priv(indio_dev); 86 87 for (i = 0; i < MS5611_PROM_WORDS_NB; i++) { 88 ret = st->read_prom_word(&indio_dev->dev, 89 i, &st->chip_info->prom[i]); 90 if (ret < 0) { 91 dev_err(&indio_dev->dev, 92 "failed to read prom at %d\n", i); 93 return ret; 94 } 95 } 96 97 if (!ms5611_prom_is_valid(st->chip_info->prom, MS5611_PROM_WORDS_NB)) { 98 dev_err(&indio_dev->dev, "PROM integrity check failed\n"); 99 return -ENODEV; 100 } 101 102 return 0; 103 } 104 105 static int ms5611_read_temp_and_pressure(struct iio_dev *indio_dev, 106 s32 *temp, s32 *pressure) 107 { 108 int ret; 109 struct ms5611_state *st = iio_priv(indio_dev); 110 111 ret = st->read_adc_temp_and_pressure(&indio_dev->dev, temp, pressure); 112 if (ret < 0) { 113 dev_err(&indio_dev->dev, 114 "failed to read temperature and pressure\n"); 115 return ret; 116 } 117 118 return st->chip_info->temp_and_pressure_compensate(st->chip_info, 119 temp, pressure); 120 } 121 122 static int ms5611_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info, 123 s32 *temp, s32 *pressure) 124 { 125 s32 t = *temp, p = *pressure; 126 s64 off, sens, dt; 127 128 dt = t - (chip_info->prom[5] << 8); 129 off = ((s64)chip_info->prom[2] << 16) + ((chip_info->prom[4] * dt) >> 7); 130 sens = ((s64)chip_info->prom[1] << 15) + ((chip_info->prom[3] * dt) >> 8); 131 132 t = 2000 + ((chip_info->prom[6] * dt) >> 23); 133 if (t < 2000) { 134 s64 off2, sens2, t2; 135 136 t2 = (dt * dt) >> 31; 137 off2 = (5 * (t - 2000) * (t - 2000)) >> 1; 138 sens2 = off2 >> 1; 139 140 if (t < -1500) { 141 s64 tmp = (t + 1500) * (t + 1500); 142 143 off2 += 7 * tmp; 144 sens2 += (11 * tmp) >> 1; 145 } 146 147 t -= t2; 148 off -= off2; 149 sens -= sens2; 150 } 151 152 *temp = t; 153 *pressure = (((p * sens) >> 21) - off) >> 15; 154 155 return 0; 156 } 157 158 static int ms5607_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info, 159 s32 *temp, s32 *pressure) 160 { 161 s32 t = *temp, p = *pressure; 162 s64 off, sens, dt; 163 164 dt = t - (chip_info->prom[5] << 8); 165 off = ((s64)chip_info->prom[2] << 17) + ((chip_info->prom[4] * dt) >> 6); 166 sens = ((s64)chip_info->prom[1] << 16) + ((chip_info->prom[3] * dt) >> 7); 167 168 t = 2000 + ((chip_info->prom[6] * dt) >> 23); 169 if (t < 2000) { 170 s64 off2, sens2, t2, tmp; 171 172 t2 = (dt * dt) >> 31; 173 tmp = (t - 2000) * (t - 2000); 174 off2 = (61 * tmp) >> 4; 175 sens2 = tmp << 1; 176 177 if (t < -1500) { 178 tmp = (t + 1500) * (t + 1500); 179 off2 += 15 * tmp; 180 sens2 += 8 * tmp; 181 } 182 183 t -= t2; 184 off -= off2; 185 sens -= sens2; 186 } 187 188 *temp = t; 189 *pressure = (((p * sens) >> 21) - off) >> 15; 190 191 return 0; 192 } 193 194 static int ms5611_reset(struct iio_dev *indio_dev) 195 { 196 int ret; 197 struct ms5611_state *st = iio_priv(indio_dev); 198 199 ret = st->reset(&indio_dev->dev); 200 if (ret < 0) { 201 dev_err(&indio_dev->dev, "failed to reset device\n"); 202 return ret; 203 } 204 205 usleep_range(3000, 4000); 206 207 return 0; 208 } 209 210 static irqreturn_t ms5611_trigger_handler(int irq, void *p) 211 { 212 struct iio_poll_func *pf = p; 213 struct iio_dev *indio_dev = pf->indio_dev; 214 struct ms5611_state *st = iio_priv(indio_dev); 215 s32 buf[4]; /* s32 (pressure) + s32 (temp) + 2 * s32 (timestamp) */ 216 int ret; 217 218 mutex_lock(&st->lock); 219 ret = ms5611_read_temp_and_pressure(indio_dev, &buf[1], &buf[0]); 220 mutex_unlock(&st->lock); 221 if (ret < 0) 222 goto err; 223 224 iio_push_to_buffers_with_timestamp(indio_dev, buf, 225 iio_get_time_ns(indio_dev)); 226 227 err: 228 iio_trigger_notify_done(indio_dev->trig); 229 230 return IRQ_HANDLED; 231 } 232 233 static int ms5611_read_raw(struct iio_dev *indio_dev, 234 struct iio_chan_spec const *chan, 235 int *val, int *val2, long mask) 236 { 237 int ret; 238 s32 temp, pressure; 239 struct ms5611_state *st = iio_priv(indio_dev); 240 241 switch (mask) { 242 case IIO_CHAN_INFO_PROCESSED: 243 mutex_lock(&st->lock); 244 ret = ms5611_read_temp_and_pressure(indio_dev, 245 &temp, &pressure); 246 mutex_unlock(&st->lock); 247 if (ret < 0) 248 return ret; 249 250 switch (chan->type) { 251 case IIO_TEMP: 252 *val = temp * 10; 253 return IIO_VAL_INT; 254 case IIO_PRESSURE: 255 *val = pressure / 1000; 256 *val2 = (pressure % 1000) * 1000; 257 return IIO_VAL_INT_PLUS_MICRO; 258 default: 259 return -EINVAL; 260 } 261 case IIO_CHAN_INFO_SCALE: 262 switch (chan->type) { 263 case IIO_TEMP: 264 *val = 10; 265 return IIO_VAL_INT; 266 case IIO_PRESSURE: 267 *val = 0; 268 *val2 = 1000; 269 return IIO_VAL_INT_PLUS_MICRO; 270 default: 271 return -EINVAL; 272 } 273 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 274 if (chan->type != IIO_TEMP && chan->type != IIO_PRESSURE) 275 break; 276 mutex_lock(&st->lock); 277 if (chan->type == IIO_TEMP) 278 *val = (int)st->temp_osr->rate; 279 else 280 *val = (int)st->pressure_osr->rate; 281 mutex_unlock(&st->lock); 282 return IIO_VAL_INT; 283 } 284 285 return -EINVAL; 286 } 287 288 static const struct ms5611_osr *ms5611_find_osr(int rate, 289 const struct ms5611_osr *osr, 290 size_t count) 291 { 292 unsigned int r; 293 294 for (r = 0; r < count; r++) 295 if ((unsigned short)rate == osr[r].rate) 296 break; 297 if (r >= count) 298 return NULL; 299 return &osr[r]; 300 } 301 302 static int ms5611_write_raw(struct iio_dev *indio_dev, 303 struct iio_chan_spec const *chan, 304 int val, int val2, long mask) 305 { 306 struct ms5611_state *st = iio_priv(indio_dev); 307 const struct ms5611_osr *osr = NULL; 308 int ret; 309 310 if (mask != IIO_CHAN_INFO_OVERSAMPLING_RATIO) 311 return -EINVAL; 312 313 if (chan->type == IIO_TEMP) 314 osr = ms5611_find_osr(val, ms5611_avail_temp_osr, 315 ARRAY_SIZE(ms5611_avail_temp_osr)); 316 else if (chan->type == IIO_PRESSURE) 317 osr = ms5611_find_osr(val, ms5611_avail_pressure_osr, 318 ARRAY_SIZE(ms5611_avail_pressure_osr)); 319 if (!osr) 320 return -EINVAL; 321 322 ret = iio_device_claim_direct_mode(indio_dev); 323 if (ret) 324 return ret; 325 326 mutex_lock(&st->lock); 327 328 if (chan->type == IIO_TEMP) 329 st->temp_osr = osr; 330 else 331 st->pressure_osr = osr; 332 333 mutex_unlock(&st->lock); 334 iio_device_release_direct_mode(indio_dev); 335 336 return 0; 337 } 338 339 static const unsigned long ms5611_scan_masks[] = {0x3, 0}; 340 341 static struct ms5611_chip_info chip_info_tbl[] = { 342 [MS5611] = { 343 .temp_and_pressure_compensate = ms5611_temp_and_pressure_compensate, 344 }, 345 [MS5607] = { 346 .temp_and_pressure_compensate = ms5607_temp_and_pressure_compensate, 347 } 348 }; 349 350 static const struct iio_chan_spec ms5611_channels[] = { 351 { 352 .type = IIO_PRESSURE, 353 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 354 BIT(IIO_CHAN_INFO_SCALE) | 355 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 356 .scan_index = 0, 357 .scan_type = { 358 .sign = 's', 359 .realbits = 32, 360 .storagebits = 32, 361 .endianness = IIO_CPU, 362 }, 363 }, 364 { 365 .type = IIO_TEMP, 366 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | 367 BIT(IIO_CHAN_INFO_SCALE) | 368 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), 369 .scan_index = 1, 370 .scan_type = { 371 .sign = 's', 372 .realbits = 32, 373 .storagebits = 32, 374 .endianness = IIO_CPU, 375 }, 376 }, 377 IIO_CHAN_SOFT_TIMESTAMP(2), 378 }; 379 380 static const struct iio_info ms5611_info = { 381 .read_raw = &ms5611_read_raw, 382 .write_raw = &ms5611_write_raw, 383 .attrs = &ms5611_attribute_group, 384 }; 385 386 static int ms5611_init(struct iio_dev *indio_dev) 387 { 388 int ret; 389 struct ms5611_state *st = iio_priv(indio_dev); 390 391 /* Enable attached regulator if any. */ 392 st->vdd = devm_regulator_get(indio_dev->dev.parent, "vdd"); 393 if (IS_ERR(st->vdd)) 394 return PTR_ERR(st->vdd); 395 396 ret = regulator_enable(st->vdd); 397 if (ret) { 398 dev_err(indio_dev->dev.parent, 399 "failed to enable Vdd supply: %d\n", ret); 400 return ret; 401 } 402 403 ret = ms5611_reset(indio_dev); 404 if (ret < 0) 405 goto err_regulator_disable; 406 407 ret = ms5611_read_prom(indio_dev); 408 if (ret < 0) 409 goto err_regulator_disable; 410 411 return 0; 412 413 err_regulator_disable: 414 regulator_disable(st->vdd); 415 return ret; 416 } 417 418 static void ms5611_fini(const struct iio_dev *indio_dev) 419 { 420 const struct ms5611_state *st = iio_priv(indio_dev); 421 422 regulator_disable(st->vdd); 423 } 424 425 int ms5611_probe(struct iio_dev *indio_dev, struct device *dev, 426 const char *name, int type) 427 { 428 int ret; 429 struct ms5611_state *st = iio_priv(indio_dev); 430 431 mutex_init(&st->lock); 432 st->chip_info = &chip_info_tbl[type]; 433 st->temp_osr = 434 &ms5611_avail_temp_osr[ARRAY_SIZE(ms5611_avail_temp_osr) - 1]; 435 st->pressure_osr = 436 &ms5611_avail_pressure_osr[ARRAY_SIZE(ms5611_avail_pressure_osr) 437 - 1]; 438 indio_dev->dev.parent = dev; 439 indio_dev->name = name; 440 indio_dev->info = &ms5611_info; 441 indio_dev->channels = ms5611_channels; 442 indio_dev->num_channels = ARRAY_SIZE(ms5611_channels); 443 indio_dev->modes = INDIO_DIRECT_MODE; 444 indio_dev->available_scan_masks = ms5611_scan_masks; 445 446 ret = ms5611_init(indio_dev); 447 if (ret < 0) 448 return ret; 449 450 ret = iio_triggered_buffer_setup(indio_dev, NULL, 451 ms5611_trigger_handler, NULL); 452 if (ret < 0) { 453 dev_err(dev, "iio triggered buffer setup failed\n"); 454 goto err_fini; 455 } 456 457 ret = iio_device_register(indio_dev); 458 if (ret < 0) { 459 dev_err(dev, "unable to register iio device\n"); 460 goto err_buffer_cleanup; 461 } 462 463 return 0; 464 465 err_buffer_cleanup: 466 iio_triggered_buffer_cleanup(indio_dev); 467 err_fini: 468 ms5611_fini(indio_dev); 469 return ret; 470 } 471 EXPORT_SYMBOL(ms5611_probe); 472 473 int ms5611_remove(struct iio_dev *indio_dev) 474 { 475 iio_device_unregister(indio_dev); 476 iio_triggered_buffer_cleanup(indio_dev); 477 ms5611_fini(indio_dev); 478 479 return 0; 480 } 481 EXPORT_SYMBOL(ms5611_remove); 482 483 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>"); 484 MODULE_DESCRIPTION("MS5611 core driver"); 485 MODULE_LICENSE("GPL v2"); 486