1 /* 2 * INA2XX Current and Power Monitors 3 * 4 * Copyright 2015 Baylibre SAS. 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 version 2 as 8 * published by the Free Software Foundation. 9 * 10 * Based on linux/drivers/iio/adc/ad7291.c 11 * Copyright 2010-2011 Analog Devices Inc. 12 * 13 * Based on linux/drivers/hwmon/ina2xx.c 14 * Copyright 2012 Lothar Felten <l-felten@ti.com> 15 * 16 * Licensed under the GPL-2 or later. 17 * 18 * IIO driver for INA219-220-226-230-231 19 * 20 * Configurable 7-bit I2C slave address from 0x40 to 0x4F 21 */ 22 23 #include <linux/delay.h> 24 #include <linux/i2c.h> 25 #include <linux/iio/iio.h> 26 #include <linux/iio/buffer.h> 27 #include <linux/iio/kfifo_buf.h> 28 #include <linux/iio/sysfs.h> 29 #include <linux/kthread.h> 30 #include <linux/module.h> 31 #include <linux/of_device.h> 32 #include <linux/regmap.h> 33 #include <linux/sched/task.h> 34 #include <linux/util_macros.h> 35 36 #include <linux/platform_data/ina2xx.h> 37 38 /* INA2XX registers definition */ 39 #define INA2XX_CONFIG 0x00 40 #define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */ 41 #define INA2XX_BUS_VOLTAGE 0x02 /* readonly */ 42 #define INA2XX_POWER 0x03 /* readonly */ 43 #define INA2XX_CURRENT 0x04 /* readonly */ 44 #define INA2XX_CALIBRATION 0x05 45 46 #define INA226_MASK_ENABLE 0x06 47 #define INA226_CVRF BIT(3) 48 49 #define INA2XX_MAX_REGISTERS 8 50 51 /* settings - depend on use case */ 52 #define INA219_CONFIG_DEFAULT 0x399F /* PGA=1/8, BRNG=32V */ 53 #define INA219_DEFAULT_IT 532 54 #define INA219_DEFAULT_BRNG 1 /* 32V */ 55 #define INA219_DEFAULT_PGA 125 /* 1000/8 */ 56 #define INA226_CONFIG_DEFAULT 0x4327 57 #define INA226_DEFAULT_AVG 4 58 #define INA226_DEFAULT_IT 1110 59 60 #define INA2XX_RSHUNT_DEFAULT 10000 61 62 /* 63 * bit masks for reading the settings in the configuration register 64 * FIXME: use regmap_fields. 65 */ 66 #define INA2XX_MODE_MASK GENMASK(3, 0) 67 68 /* Gain for VShunt: 1/8 (default), 1/4, 1/2, 1 */ 69 #define INA219_PGA_MASK GENMASK(12, 11) 70 #define INA219_SHIFT_PGA(val) ((val) << 11) 71 72 /* VBus range: 32V (default), 16V */ 73 #define INA219_BRNG_MASK BIT(13) 74 #define INA219_SHIFT_BRNG(val) ((val) << 13) 75 76 /* Averaging for VBus/VShunt/Power */ 77 #define INA226_AVG_MASK GENMASK(11, 9) 78 #define INA226_SHIFT_AVG(val) ((val) << 9) 79 80 /* Integration time for VBus */ 81 #define INA219_ITB_MASK GENMASK(10, 7) 82 #define INA219_SHIFT_ITB(val) ((val) << 7) 83 #define INA226_ITB_MASK GENMASK(8, 6) 84 #define INA226_SHIFT_ITB(val) ((val) << 6) 85 86 /* Integration time for VShunt */ 87 #define INA219_ITS_MASK GENMASK(6, 3) 88 #define INA219_SHIFT_ITS(val) ((val) << 3) 89 #define INA226_ITS_MASK GENMASK(5, 3) 90 #define INA226_SHIFT_ITS(val) ((val) << 3) 91 92 /* INA219 Bus voltage register, low bits are flags */ 93 #define INA219_OVF BIT(0) 94 #define INA219_CNVR BIT(1) 95 #define INA219_BUS_VOLTAGE_SHIFT 3 96 97 /* Cosmetic macro giving the sampling period for a full P=UxI cycle */ 98 #define SAMPLING_PERIOD(c) ((c->int_time_vbus + c->int_time_vshunt) \ 99 * c->avg) 100 101 static bool ina2xx_is_writeable_reg(struct device *dev, unsigned int reg) 102 { 103 return (reg == INA2XX_CONFIG) || (reg > INA2XX_CURRENT); 104 } 105 106 static bool ina2xx_is_volatile_reg(struct device *dev, unsigned int reg) 107 { 108 return (reg != INA2XX_CONFIG); 109 } 110 111 static inline bool is_signed_reg(unsigned int reg) 112 { 113 return (reg == INA2XX_SHUNT_VOLTAGE) || (reg == INA2XX_CURRENT); 114 } 115 116 static const struct regmap_config ina2xx_regmap_config = { 117 .reg_bits = 8, 118 .val_bits = 16, 119 .max_register = INA2XX_MAX_REGISTERS, 120 .writeable_reg = ina2xx_is_writeable_reg, 121 .volatile_reg = ina2xx_is_volatile_reg, 122 }; 123 124 enum ina2xx_ids { ina219, ina226 }; 125 126 struct ina2xx_config { 127 u16 config_default; 128 int calibration_value; 129 int shunt_voltage_lsb; /* nV */ 130 int bus_voltage_shift; /* position of lsb */ 131 int bus_voltage_lsb; /* uV */ 132 /* fixed relation between current and power lsb, uW/uA */ 133 int power_lsb_factor; 134 enum ina2xx_ids chip_id; 135 }; 136 137 struct ina2xx_chip_info { 138 struct regmap *regmap; 139 struct task_struct *task; 140 const struct ina2xx_config *config; 141 struct mutex state_lock; 142 unsigned int shunt_resistor_uohm; 143 int avg; 144 int int_time_vbus; /* Bus voltage integration time uS */ 145 int int_time_vshunt; /* Shunt voltage integration time uS */ 146 int range_vbus; /* Bus voltage maximum in V */ 147 int pga_gain_vshunt; /* Shunt voltage PGA gain */ 148 bool allow_async_readout; 149 /* data buffer needs space for channel data and timestamp */ 150 struct { 151 u16 chan[4]; 152 u64 ts __aligned(8); 153 } scan; 154 }; 155 156 static const struct ina2xx_config ina2xx_config[] = { 157 [ina219] = { 158 .config_default = INA219_CONFIG_DEFAULT, 159 .calibration_value = 4096, 160 .shunt_voltage_lsb = 10000, 161 .bus_voltage_shift = INA219_BUS_VOLTAGE_SHIFT, 162 .bus_voltage_lsb = 4000, 163 .power_lsb_factor = 20, 164 .chip_id = ina219, 165 }, 166 [ina226] = { 167 .config_default = INA226_CONFIG_DEFAULT, 168 .calibration_value = 2048, 169 .shunt_voltage_lsb = 2500, 170 .bus_voltage_shift = 0, 171 .bus_voltage_lsb = 1250, 172 .power_lsb_factor = 25, 173 .chip_id = ina226, 174 }, 175 }; 176 177 static int ina2xx_read_raw(struct iio_dev *indio_dev, 178 struct iio_chan_spec const *chan, 179 int *val, int *val2, long mask) 180 { 181 int ret; 182 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 183 unsigned int regval; 184 185 switch (mask) { 186 case IIO_CHAN_INFO_RAW: 187 ret = regmap_read(chip->regmap, chan->address, ®val); 188 if (ret) 189 return ret; 190 191 if (is_signed_reg(chan->address)) 192 *val = (s16) regval; 193 else 194 *val = regval; 195 196 if (chan->address == INA2XX_BUS_VOLTAGE) 197 *val >>= chip->config->bus_voltage_shift; 198 199 return IIO_VAL_INT; 200 201 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 202 *val = chip->avg; 203 return IIO_VAL_INT; 204 205 case IIO_CHAN_INFO_INT_TIME: 206 *val = 0; 207 if (chan->address == INA2XX_SHUNT_VOLTAGE) 208 *val2 = chip->int_time_vshunt; 209 else 210 *val2 = chip->int_time_vbus; 211 212 return IIO_VAL_INT_PLUS_MICRO; 213 214 case IIO_CHAN_INFO_SAMP_FREQ: 215 /* 216 * Sample freq is read only, it is a consequence of 217 * 1/AVG*(CT_bus+CT_shunt). 218 */ 219 *val = DIV_ROUND_CLOSEST(1000000, SAMPLING_PERIOD(chip)); 220 221 return IIO_VAL_INT; 222 223 case IIO_CHAN_INFO_SCALE: 224 switch (chan->address) { 225 case INA2XX_SHUNT_VOLTAGE: 226 /* processed (mV) = raw * lsb(nV) / 1000000 */ 227 *val = chip->config->shunt_voltage_lsb; 228 *val2 = 1000000; 229 return IIO_VAL_FRACTIONAL; 230 231 case INA2XX_BUS_VOLTAGE: 232 /* processed (mV) = raw * lsb (uV) / 1000 */ 233 *val = chip->config->bus_voltage_lsb; 234 *val2 = 1000; 235 return IIO_VAL_FRACTIONAL; 236 237 case INA2XX_CURRENT: 238 /* 239 * processed (mA) = raw * current_lsb (mA) 240 * current_lsb (mA) = shunt_voltage_lsb (nV) / 241 * shunt_resistor (uOhm) 242 */ 243 *val = chip->config->shunt_voltage_lsb; 244 *val2 = chip->shunt_resistor_uohm; 245 return IIO_VAL_FRACTIONAL; 246 247 case INA2XX_POWER: 248 /* 249 * processed (mW) = raw * power_lsb (mW) 250 * power_lsb (mW) = power_lsb_factor (mW/mA) * 251 * current_lsb (mA) 252 */ 253 *val = chip->config->power_lsb_factor * 254 chip->config->shunt_voltage_lsb; 255 *val2 = chip->shunt_resistor_uohm; 256 return IIO_VAL_FRACTIONAL; 257 } 258 return -EINVAL; 259 260 case IIO_CHAN_INFO_HARDWAREGAIN: 261 switch (chan->address) { 262 case INA2XX_SHUNT_VOLTAGE: 263 *val = chip->pga_gain_vshunt; 264 *val2 = 1000; 265 return IIO_VAL_FRACTIONAL; 266 267 case INA2XX_BUS_VOLTAGE: 268 *val = chip->range_vbus == 32 ? 1 : 2; 269 return IIO_VAL_INT; 270 } 271 return -EINVAL; 272 } 273 274 return -EINVAL; 275 } 276 277 /* 278 * Available averaging rates for ina226. The indices correspond with 279 * the bit values expected by the chip (according to the ina226 datasheet, 280 * table 3 AVG bit settings, found at 281 * https://www.ti.com/lit/ds/symlink/ina226.pdf. 282 */ 283 static const int ina226_avg_tab[] = { 1, 4, 16, 64, 128, 256, 512, 1024 }; 284 285 static int ina226_set_average(struct ina2xx_chip_info *chip, unsigned int val, 286 unsigned int *config) 287 { 288 int bits; 289 290 if (val > 1024 || val < 1) 291 return -EINVAL; 292 293 bits = find_closest(val, ina226_avg_tab, 294 ARRAY_SIZE(ina226_avg_tab)); 295 296 chip->avg = ina226_avg_tab[bits]; 297 298 *config &= ~INA226_AVG_MASK; 299 *config |= INA226_SHIFT_AVG(bits) & INA226_AVG_MASK; 300 301 return 0; 302 } 303 304 /* Conversion times in uS */ 305 static const int ina226_conv_time_tab[] = { 140, 204, 332, 588, 1100, 306 2116, 4156, 8244 }; 307 308 static int ina226_set_int_time_vbus(struct ina2xx_chip_info *chip, 309 unsigned int val_us, unsigned int *config) 310 { 311 int bits; 312 313 if (val_us > 8244 || val_us < 140) 314 return -EINVAL; 315 316 bits = find_closest(val_us, ina226_conv_time_tab, 317 ARRAY_SIZE(ina226_conv_time_tab)); 318 319 chip->int_time_vbus = ina226_conv_time_tab[bits]; 320 321 *config &= ~INA226_ITB_MASK; 322 *config |= INA226_SHIFT_ITB(bits) & INA226_ITB_MASK; 323 324 return 0; 325 } 326 327 static int ina226_set_int_time_vshunt(struct ina2xx_chip_info *chip, 328 unsigned int val_us, unsigned int *config) 329 { 330 int bits; 331 332 if (val_us > 8244 || val_us < 140) 333 return -EINVAL; 334 335 bits = find_closest(val_us, ina226_conv_time_tab, 336 ARRAY_SIZE(ina226_conv_time_tab)); 337 338 chip->int_time_vshunt = ina226_conv_time_tab[bits]; 339 340 *config &= ~INA226_ITS_MASK; 341 *config |= INA226_SHIFT_ITS(bits) & INA226_ITS_MASK; 342 343 return 0; 344 } 345 346 /* Conversion times in uS. */ 347 static const int ina219_conv_time_tab_subsample[] = { 84, 148, 276, 532 }; 348 static const int ina219_conv_time_tab_average[] = { 532, 1060, 2130, 4260, 349 8510, 17020, 34050, 68100}; 350 351 static int ina219_lookup_int_time(unsigned int *val_us, int *bits) 352 { 353 if (*val_us > 68100 || *val_us < 84) 354 return -EINVAL; 355 356 if (*val_us <= 532) { 357 *bits = find_closest(*val_us, ina219_conv_time_tab_subsample, 358 ARRAY_SIZE(ina219_conv_time_tab_subsample)); 359 *val_us = ina219_conv_time_tab_subsample[*bits]; 360 } else { 361 *bits = find_closest(*val_us, ina219_conv_time_tab_average, 362 ARRAY_SIZE(ina219_conv_time_tab_average)); 363 *val_us = ina219_conv_time_tab_average[*bits]; 364 *bits |= 0x8; 365 } 366 367 return 0; 368 } 369 370 static int ina219_set_int_time_vbus(struct ina2xx_chip_info *chip, 371 unsigned int val_us, unsigned int *config) 372 { 373 int bits, ret; 374 unsigned int val_us_best = val_us; 375 376 ret = ina219_lookup_int_time(&val_us_best, &bits); 377 if (ret) 378 return ret; 379 380 chip->int_time_vbus = val_us_best; 381 382 *config &= ~INA219_ITB_MASK; 383 *config |= INA219_SHIFT_ITB(bits) & INA219_ITB_MASK; 384 385 return 0; 386 } 387 388 static int ina219_set_int_time_vshunt(struct ina2xx_chip_info *chip, 389 unsigned int val_us, unsigned int *config) 390 { 391 int bits, ret; 392 unsigned int val_us_best = val_us; 393 394 ret = ina219_lookup_int_time(&val_us_best, &bits); 395 if (ret) 396 return ret; 397 398 chip->int_time_vshunt = val_us_best; 399 400 *config &= ~INA219_ITS_MASK; 401 *config |= INA219_SHIFT_ITS(bits) & INA219_ITS_MASK; 402 403 return 0; 404 } 405 406 static const int ina219_vbus_range_tab[] = { 1, 2 }; 407 static int ina219_set_vbus_range_denom(struct ina2xx_chip_info *chip, 408 unsigned int range, 409 unsigned int *config) 410 { 411 if (range == 1) 412 chip->range_vbus = 32; 413 else if (range == 2) 414 chip->range_vbus = 16; 415 else 416 return -EINVAL; 417 418 *config &= ~INA219_BRNG_MASK; 419 *config |= INA219_SHIFT_BRNG(range == 1 ? 1 : 0) & INA219_BRNG_MASK; 420 421 return 0; 422 } 423 424 static const int ina219_vshunt_gain_tab[] = { 125, 250, 500, 1000 }; 425 static const int ina219_vshunt_gain_frac[] = { 426 125, 1000, 250, 1000, 500, 1000, 1000, 1000 }; 427 428 static int ina219_set_vshunt_pga_gain(struct ina2xx_chip_info *chip, 429 unsigned int gain, 430 unsigned int *config) 431 { 432 int bits; 433 434 if (gain < 125 || gain > 1000) 435 return -EINVAL; 436 437 bits = find_closest(gain, ina219_vshunt_gain_tab, 438 ARRAY_SIZE(ina219_vshunt_gain_tab)); 439 440 chip->pga_gain_vshunt = ina219_vshunt_gain_tab[bits]; 441 bits = 3 - bits; 442 443 *config &= ~INA219_PGA_MASK; 444 *config |= INA219_SHIFT_PGA(bits) & INA219_PGA_MASK; 445 446 return 0; 447 } 448 449 static int ina2xx_read_avail(struct iio_dev *indio_dev, 450 struct iio_chan_spec const *chan, 451 const int **vals, int *type, int *length, 452 long mask) 453 { 454 switch (mask) { 455 case IIO_CHAN_INFO_HARDWAREGAIN: 456 switch (chan->address) { 457 case INA2XX_SHUNT_VOLTAGE: 458 *type = IIO_VAL_FRACTIONAL; 459 *length = sizeof(ina219_vshunt_gain_frac) / sizeof(int); 460 *vals = ina219_vshunt_gain_frac; 461 return IIO_AVAIL_LIST; 462 463 case INA2XX_BUS_VOLTAGE: 464 *type = IIO_VAL_INT; 465 *length = sizeof(ina219_vbus_range_tab) / sizeof(int); 466 *vals = ina219_vbus_range_tab; 467 return IIO_AVAIL_LIST; 468 } 469 } 470 471 return -EINVAL; 472 } 473 474 static int ina2xx_write_raw(struct iio_dev *indio_dev, 475 struct iio_chan_spec const *chan, 476 int val, int val2, long mask) 477 { 478 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 479 unsigned int config, tmp; 480 int ret; 481 482 if (iio_buffer_enabled(indio_dev)) 483 return -EBUSY; 484 485 mutex_lock(&chip->state_lock); 486 487 ret = regmap_read(chip->regmap, INA2XX_CONFIG, &config); 488 if (ret) 489 goto err; 490 491 tmp = config; 492 493 switch (mask) { 494 case IIO_CHAN_INFO_OVERSAMPLING_RATIO: 495 ret = ina226_set_average(chip, val, &tmp); 496 break; 497 498 case IIO_CHAN_INFO_INT_TIME: 499 if (chip->config->chip_id == ina226) { 500 if (chan->address == INA2XX_SHUNT_VOLTAGE) 501 ret = ina226_set_int_time_vshunt(chip, val2, 502 &tmp); 503 else 504 ret = ina226_set_int_time_vbus(chip, val2, 505 &tmp); 506 } else { 507 if (chan->address == INA2XX_SHUNT_VOLTAGE) 508 ret = ina219_set_int_time_vshunt(chip, val2, 509 &tmp); 510 else 511 ret = ina219_set_int_time_vbus(chip, val2, 512 &tmp); 513 } 514 break; 515 516 case IIO_CHAN_INFO_HARDWAREGAIN: 517 if (chan->address == INA2XX_SHUNT_VOLTAGE) 518 ret = ina219_set_vshunt_pga_gain(chip, val * 1000 + 519 val2 / 1000, &tmp); 520 else 521 ret = ina219_set_vbus_range_denom(chip, val, &tmp); 522 break; 523 524 default: 525 ret = -EINVAL; 526 } 527 528 if (!ret && (tmp != config)) 529 ret = regmap_write(chip->regmap, INA2XX_CONFIG, tmp); 530 err: 531 mutex_unlock(&chip->state_lock); 532 533 return ret; 534 } 535 536 static ssize_t ina2xx_allow_async_readout_show(struct device *dev, 537 struct device_attribute *attr, 538 char *buf) 539 { 540 struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev)); 541 542 return sprintf(buf, "%d\n", chip->allow_async_readout); 543 } 544 545 static ssize_t ina2xx_allow_async_readout_store(struct device *dev, 546 struct device_attribute *attr, 547 const char *buf, size_t len) 548 { 549 struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev)); 550 bool val; 551 int ret; 552 553 ret = strtobool((const char *) buf, &val); 554 if (ret) 555 return ret; 556 557 chip->allow_async_readout = val; 558 559 return len; 560 } 561 562 /* 563 * Calibration register is set to the best value, which eliminates 564 * truncation errors on calculating current register in hardware. 565 * According to datasheet (INA 226: eq. 3, INA219: eq. 4) the best values 566 * are 2048 for ina226 and 4096 for ina219. They are hardcoded as 567 * calibration_value. 568 */ 569 static int ina2xx_set_calibration(struct ina2xx_chip_info *chip) 570 { 571 return regmap_write(chip->regmap, INA2XX_CALIBRATION, 572 chip->config->calibration_value); 573 } 574 575 static int set_shunt_resistor(struct ina2xx_chip_info *chip, unsigned int val) 576 { 577 if (val == 0 || val > INT_MAX) 578 return -EINVAL; 579 580 chip->shunt_resistor_uohm = val; 581 582 return 0; 583 } 584 585 static ssize_t ina2xx_shunt_resistor_show(struct device *dev, 586 struct device_attribute *attr, 587 char *buf) 588 { 589 struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev)); 590 int vals[2] = { chip->shunt_resistor_uohm, 1000000 }; 591 592 return iio_format_value(buf, IIO_VAL_FRACTIONAL, 1, vals); 593 } 594 595 static ssize_t ina2xx_shunt_resistor_store(struct device *dev, 596 struct device_attribute *attr, 597 const char *buf, size_t len) 598 { 599 struct ina2xx_chip_info *chip = iio_priv(dev_to_iio_dev(dev)); 600 int val, val_fract, ret; 601 602 ret = iio_str_to_fixpoint(buf, 100000, &val, &val_fract); 603 if (ret) 604 return ret; 605 606 ret = set_shunt_resistor(chip, val * 1000000 + val_fract); 607 if (ret) 608 return ret; 609 610 return len; 611 } 612 613 #define INA219_CHAN(_type, _index, _address) { \ 614 .type = (_type), \ 615 .address = (_address), \ 616 .indexed = 1, \ 617 .channel = (_index), \ 618 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 619 BIT(IIO_CHAN_INFO_SCALE), \ 620 .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 621 .scan_index = (_index), \ 622 .scan_type = { \ 623 .sign = 'u', \ 624 .realbits = 16, \ 625 .storagebits = 16, \ 626 .endianness = IIO_CPU, \ 627 } \ 628 } 629 630 #define INA226_CHAN(_type, _index, _address) { \ 631 .type = (_type), \ 632 .address = (_address), \ 633 .indexed = 1, \ 634 .channel = (_index), \ 635 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 636 BIT(IIO_CHAN_INFO_SCALE), \ 637 .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ 638 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ 639 .scan_index = (_index), \ 640 .scan_type = { \ 641 .sign = 'u', \ 642 .realbits = 16, \ 643 .storagebits = 16, \ 644 .endianness = IIO_CPU, \ 645 } \ 646 } 647 648 /* 649 * Sampling Freq is a consequence of the integration times of 650 * the Voltage channels. 651 */ 652 #define INA219_CHAN_VOLTAGE(_index, _address, _shift) { \ 653 .type = IIO_VOLTAGE, \ 654 .address = (_address), \ 655 .indexed = 1, \ 656 .channel = (_index), \ 657 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 658 BIT(IIO_CHAN_INFO_SCALE) | \ 659 BIT(IIO_CHAN_INFO_INT_TIME) | \ 660 BIT(IIO_CHAN_INFO_HARDWAREGAIN), \ 661 .info_mask_separate_available = \ 662 BIT(IIO_CHAN_INFO_HARDWAREGAIN), \ 663 .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 664 .scan_index = (_index), \ 665 .scan_type = { \ 666 .sign = 'u', \ 667 .shift = _shift, \ 668 .realbits = 16 - _shift, \ 669 .storagebits = 16, \ 670 .endianness = IIO_LE, \ 671 } \ 672 } 673 674 #define INA226_CHAN_VOLTAGE(_index, _address) { \ 675 .type = IIO_VOLTAGE, \ 676 .address = (_address), \ 677 .indexed = 1, \ 678 .channel = (_index), \ 679 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 680 BIT(IIO_CHAN_INFO_SCALE) | \ 681 BIT(IIO_CHAN_INFO_INT_TIME), \ 682 .info_mask_shared_by_dir = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \ 683 BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ 684 .scan_index = (_index), \ 685 .scan_type = { \ 686 .sign = 'u', \ 687 .realbits = 16, \ 688 .storagebits = 16, \ 689 .endianness = IIO_LE, \ 690 } \ 691 } 692 693 694 static const struct iio_chan_spec ina226_channels[] = { 695 INA226_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE), 696 INA226_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE), 697 INA226_CHAN(IIO_POWER, 2, INA2XX_POWER), 698 INA226_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT), 699 IIO_CHAN_SOFT_TIMESTAMP(4), 700 }; 701 702 static const struct iio_chan_spec ina219_channels[] = { 703 INA219_CHAN_VOLTAGE(0, INA2XX_SHUNT_VOLTAGE, 0), 704 INA219_CHAN_VOLTAGE(1, INA2XX_BUS_VOLTAGE, INA219_BUS_VOLTAGE_SHIFT), 705 INA219_CHAN(IIO_POWER, 2, INA2XX_POWER), 706 INA219_CHAN(IIO_CURRENT, 3, INA2XX_CURRENT), 707 IIO_CHAN_SOFT_TIMESTAMP(4), 708 }; 709 710 static int ina2xx_conversion_ready(struct iio_dev *indio_dev) 711 { 712 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 713 int ret; 714 unsigned int alert; 715 716 /* 717 * Because the timer thread and the chip conversion clock 718 * are asynchronous, the period difference will eventually 719 * result in reading V[k-1] again, or skip V[k] at time Tk. 720 * In order to resync the timer with the conversion process 721 * we check the ConVersionReadyFlag. 722 * On hardware that supports using the ALERT pin to toggle a 723 * GPIO a triggered buffer could be used instead. 724 * For now, we do an extra read of the MASK_ENABLE register (INA226) 725 * resp. the BUS_VOLTAGE register (INA219). 726 */ 727 if (chip->config->chip_id == ina226) { 728 ret = regmap_read(chip->regmap, 729 INA226_MASK_ENABLE, &alert); 730 alert &= INA226_CVRF; 731 } else { 732 ret = regmap_read(chip->regmap, 733 INA2XX_BUS_VOLTAGE, &alert); 734 alert &= INA219_CNVR; 735 } 736 737 if (ret < 0) 738 return ret; 739 740 return !!alert; 741 } 742 743 static int ina2xx_work_buffer(struct iio_dev *indio_dev) 744 { 745 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 746 int bit, ret, i = 0; 747 s64 time; 748 749 time = iio_get_time_ns(indio_dev); 750 751 /* 752 * Single register reads: bulk_read will not work with ina226/219 753 * as there is no auto-increment of the register pointer. 754 */ 755 for_each_set_bit(bit, indio_dev->active_scan_mask, 756 indio_dev->masklength) { 757 unsigned int val; 758 759 ret = regmap_read(chip->regmap, 760 INA2XX_SHUNT_VOLTAGE + bit, &val); 761 if (ret < 0) 762 return ret; 763 764 chip->scan.chan[i++] = val; 765 } 766 767 iio_push_to_buffers_with_timestamp(indio_dev, &chip->scan, time); 768 769 return 0; 770 }; 771 772 static int ina2xx_capture_thread(void *data) 773 { 774 struct iio_dev *indio_dev = data; 775 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 776 int sampling_us = SAMPLING_PERIOD(chip); 777 int ret; 778 struct timespec64 next, now, delta; 779 s64 delay_us; 780 781 /* 782 * Poll a bit faster than the chip internal Fs, in case 783 * we wish to sync with the conversion ready flag. 784 */ 785 if (!chip->allow_async_readout) 786 sampling_us -= 200; 787 788 ktime_get_ts64(&next); 789 790 do { 791 while (!chip->allow_async_readout) { 792 ret = ina2xx_conversion_ready(indio_dev); 793 if (ret < 0) 794 return ret; 795 796 /* 797 * If the conversion was not yet finished, 798 * reset the reference timestamp. 799 */ 800 if (ret == 0) 801 ktime_get_ts64(&next); 802 else 803 break; 804 } 805 806 ret = ina2xx_work_buffer(indio_dev); 807 if (ret < 0) 808 return ret; 809 810 ktime_get_ts64(&now); 811 812 /* 813 * Advance the timestamp for the next poll by one sampling 814 * interval, and sleep for the remainder (next - now) 815 * In case "next" has already passed, the interval is added 816 * multiple times, i.e. samples are dropped. 817 */ 818 do { 819 timespec64_add_ns(&next, 1000 * sampling_us); 820 delta = timespec64_sub(next, now); 821 delay_us = div_s64(timespec64_to_ns(&delta), 1000); 822 } while (delay_us <= 0); 823 824 usleep_range(delay_us, (delay_us * 3) >> 1); 825 826 } while (!kthread_should_stop()); 827 828 return 0; 829 } 830 831 static int ina2xx_buffer_enable(struct iio_dev *indio_dev) 832 { 833 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 834 unsigned int sampling_us = SAMPLING_PERIOD(chip); 835 struct task_struct *task; 836 837 dev_dbg(&indio_dev->dev, "Enabling buffer w/ scan_mask %02x, freq = %d, avg =%u\n", 838 (unsigned int)(*indio_dev->active_scan_mask), 839 1000000 / sampling_us, chip->avg); 840 841 dev_dbg(&indio_dev->dev, "Expected work period: %u us\n", sampling_us); 842 dev_dbg(&indio_dev->dev, "Async readout mode: %d\n", 843 chip->allow_async_readout); 844 845 task = kthread_create(ina2xx_capture_thread, (void *)indio_dev, 846 "%s:%d-%uus", indio_dev->name, 847 iio_device_id(indio_dev), 848 sampling_us); 849 if (IS_ERR(task)) 850 return PTR_ERR(task); 851 852 get_task_struct(task); 853 wake_up_process(task); 854 chip->task = task; 855 856 return 0; 857 } 858 859 static int ina2xx_buffer_disable(struct iio_dev *indio_dev) 860 { 861 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 862 863 if (chip->task) { 864 kthread_stop(chip->task); 865 put_task_struct(chip->task); 866 chip->task = NULL; 867 } 868 869 return 0; 870 } 871 872 static const struct iio_buffer_setup_ops ina2xx_setup_ops = { 873 .postenable = &ina2xx_buffer_enable, 874 .predisable = &ina2xx_buffer_disable, 875 }; 876 877 static int ina2xx_debug_reg(struct iio_dev *indio_dev, 878 unsigned reg, unsigned writeval, unsigned *readval) 879 { 880 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 881 882 if (!readval) 883 return regmap_write(chip->regmap, reg, writeval); 884 885 return regmap_read(chip->regmap, reg, readval); 886 } 887 888 /* Possible integration times for vshunt and vbus */ 889 static IIO_CONST_ATTR_NAMED(ina219_integration_time_available, 890 integration_time_available, 891 "0.000084 0.000148 0.000276 0.000532 0.001060 0.002130 0.004260 0.008510 0.017020 0.034050 0.068100"); 892 893 static IIO_CONST_ATTR_NAMED(ina226_integration_time_available, 894 integration_time_available, 895 "0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244"); 896 897 static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR, 898 ina2xx_allow_async_readout_show, 899 ina2xx_allow_async_readout_store, 0); 900 901 static IIO_DEVICE_ATTR(in_shunt_resistor, S_IRUGO | S_IWUSR, 902 ina2xx_shunt_resistor_show, 903 ina2xx_shunt_resistor_store, 0); 904 905 static struct attribute *ina219_attributes[] = { 906 &iio_dev_attr_in_allow_async_readout.dev_attr.attr, 907 &iio_const_attr_ina219_integration_time_available.dev_attr.attr, 908 &iio_dev_attr_in_shunt_resistor.dev_attr.attr, 909 NULL, 910 }; 911 912 static struct attribute *ina226_attributes[] = { 913 &iio_dev_attr_in_allow_async_readout.dev_attr.attr, 914 &iio_const_attr_ina226_integration_time_available.dev_attr.attr, 915 &iio_dev_attr_in_shunt_resistor.dev_attr.attr, 916 NULL, 917 }; 918 919 static const struct attribute_group ina219_attribute_group = { 920 .attrs = ina219_attributes, 921 }; 922 923 static const struct attribute_group ina226_attribute_group = { 924 .attrs = ina226_attributes, 925 }; 926 927 static const struct iio_info ina219_info = { 928 .attrs = &ina219_attribute_group, 929 .read_raw = ina2xx_read_raw, 930 .read_avail = ina2xx_read_avail, 931 .write_raw = ina2xx_write_raw, 932 .debugfs_reg_access = ina2xx_debug_reg, 933 }; 934 935 static const struct iio_info ina226_info = { 936 .attrs = &ina226_attribute_group, 937 .read_raw = ina2xx_read_raw, 938 .write_raw = ina2xx_write_raw, 939 .debugfs_reg_access = ina2xx_debug_reg, 940 }; 941 942 /* Initialize the configuration and calibration registers. */ 943 static int ina2xx_init(struct ina2xx_chip_info *chip, unsigned int config) 944 { 945 int ret = regmap_write(chip->regmap, INA2XX_CONFIG, config); 946 if (ret) 947 return ret; 948 949 return ina2xx_set_calibration(chip); 950 } 951 952 static int ina2xx_probe(struct i2c_client *client, 953 const struct i2c_device_id *id) 954 { 955 struct ina2xx_chip_info *chip; 956 struct iio_dev *indio_dev; 957 unsigned int val; 958 enum ina2xx_ids type; 959 int ret; 960 961 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); 962 if (!indio_dev) 963 return -ENOMEM; 964 965 chip = iio_priv(indio_dev); 966 967 /* This is only used for device removal purposes. */ 968 i2c_set_clientdata(client, indio_dev); 969 970 chip->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config); 971 if (IS_ERR(chip->regmap)) { 972 dev_err(&client->dev, "failed to allocate register map\n"); 973 return PTR_ERR(chip->regmap); 974 } 975 976 if (client->dev.of_node) 977 type = (enum ina2xx_ids)of_device_get_match_data(&client->dev); 978 else 979 type = id->driver_data; 980 chip->config = &ina2xx_config[type]; 981 982 mutex_init(&chip->state_lock); 983 984 if (of_property_read_u32(client->dev.of_node, 985 "shunt-resistor", &val) < 0) { 986 struct ina2xx_platform_data *pdata = 987 dev_get_platdata(&client->dev); 988 989 if (pdata) 990 val = pdata->shunt_uohms; 991 else 992 val = INA2XX_RSHUNT_DEFAULT; 993 } 994 995 ret = set_shunt_resistor(chip, val); 996 if (ret) 997 return ret; 998 999 /* Patch the current config register with default. */ 1000 val = chip->config->config_default; 1001 1002 if (id->driver_data == ina226) { 1003 ina226_set_average(chip, INA226_DEFAULT_AVG, &val); 1004 ina226_set_int_time_vbus(chip, INA226_DEFAULT_IT, &val); 1005 ina226_set_int_time_vshunt(chip, INA226_DEFAULT_IT, &val); 1006 } else { 1007 chip->avg = 1; 1008 ina219_set_int_time_vbus(chip, INA219_DEFAULT_IT, &val); 1009 ina219_set_int_time_vshunt(chip, INA219_DEFAULT_IT, &val); 1010 ina219_set_vbus_range_denom(chip, INA219_DEFAULT_BRNG, &val); 1011 ina219_set_vshunt_pga_gain(chip, INA219_DEFAULT_PGA, &val); 1012 } 1013 1014 ret = ina2xx_init(chip, val); 1015 if (ret) { 1016 dev_err(&client->dev, "error configuring the device\n"); 1017 return ret; 1018 } 1019 1020 indio_dev->modes = INDIO_DIRECT_MODE; 1021 if (id->driver_data == ina226) { 1022 indio_dev->channels = ina226_channels; 1023 indio_dev->num_channels = ARRAY_SIZE(ina226_channels); 1024 indio_dev->info = &ina226_info; 1025 } else { 1026 indio_dev->channels = ina219_channels; 1027 indio_dev->num_channels = ARRAY_SIZE(ina219_channels); 1028 indio_dev->info = &ina219_info; 1029 } 1030 indio_dev->name = id->name; 1031 1032 ret = devm_iio_kfifo_buffer_setup(&client->dev, indio_dev, 1033 INDIO_BUFFER_SOFTWARE, 1034 &ina2xx_setup_ops); 1035 if (ret) 1036 return ret; 1037 1038 return iio_device_register(indio_dev); 1039 } 1040 1041 static int ina2xx_remove(struct i2c_client *client) 1042 { 1043 struct iio_dev *indio_dev = i2c_get_clientdata(client); 1044 struct ina2xx_chip_info *chip = iio_priv(indio_dev); 1045 1046 iio_device_unregister(indio_dev); 1047 1048 /* Powerdown */ 1049 return regmap_update_bits(chip->regmap, INA2XX_CONFIG, 1050 INA2XX_MODE_MASK, 0); 1051 } 1052 1053 static const struct i2c_device_id ina2xx_id[] = { 1054 {"ina219", ina219}, 1055 {"ina220", ina219}, 1056 {"ina226", ina226}, 1057 {"ina230", ina226}, 1058 {"ina231", ina226}, 1059 {} 1060 }; 1061 MODULE_DEVICE_TABLE(i2c, ina2xx_id); 1062 1063 static const struct of_device_id ina2xx_of_match[] = { 1064 { 1065 .compatible = "ti,ina219", 1066 .data = (void *)ina219 1067 }, 1068 { 1069 .compatible = "ti,ina220", 1070 .data = (void *)ina219 1071 }, 1072 { 1073 .compatible = "ti,ina226", 1074 .data = (void *)ina226 1075 }, 1076 { 1077 .compatible = "ti,ina230", 1078 .data = (void *)ina226 1079 }, 1080 { 1081 .compatible = "ti,ina231", 1082 .data = (void *)ina226 1083 }, 1084 {}, 1085 }; 1086 MODULE_DEVICE_TABLE(of, ina2xx_of_match); 1087 1088 static struct i2c_driver ina2xx_driver = { 1089 .driver = { 1090 .name = KBUILD_MODNAME, 1091 .of_match_table = ina2xx_of_match, 1092 }, 1093 .probe = ina2xx_probe, 1094 .remove = ina2xx_remove, 1095 .id_table = ina2xx_id, 1096 }; 1097 module_i2c_driver(ina2xx_driver); 1098 1099 MODULE_AUTHOR("Marc Titinger <marc.titinger@baylibre.com>"); 1100 MODULE_DESCRIPTION("Texas Instruments INA2XX ADC driver"); 1101 MODULE_LICENSE("GPL v2"); 1102