drivers/iio/adc/ina2xx-adc.c

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