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