drivers/iio/health/afe4403.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * AFE4403 Heart Rate Monitors and Low-Cost Pulse Oximeters
   4  *
   5  * Copyright (C) 2015-2016 Texas Instruments Incorporated - https://www.ti.com/
   6  *      Andrew F. Davis <afd@ti.com>
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/err.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/regmap.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/sysfs.h>
  17 #include <linux/regulator/consumer.h>
  18
  19 #include <linux/iio/iio.h>
  20 #include <linux/iio/sysfs.h>
  21 #include <linux/iio/buffer.h>
  22 #include <linux/iio/trigger.h>
  23 #include <linux/iio/triggered_buffer.h>
  24 #include <linux/iio/trigger_consumer.h>
  25
  26 #include <asm/unaligned.h>
  27
  28 #include "afe440x.h"
  29
  30 #define AFE4403_DRIVER_NAME             "afe4403"
  31
  32 /* AFE4403 Registers */
  33 #define AFE4403_TIAGAIN                 0x20
  34 #define AFE4403_TIA_AMB_GAIN            0x21
  35
  36 enum afe4403_fields {
  37         /* Gains */
  38         F_RF_LED1, F_CF_LED1,
  39         F_RF_LED, F_CF_LED,
  40
  41         /* LED Current */
  42         F_ILED1, F_ILED2,
  43
  44         /* sentinel */
  45         F_MAX_FIELDS
  46 };
  47
  48 static const struct reg_field afe4403_reg_fields[] = {
  49         /* Gains */
  50         [F_RF_LED1]     = REG_FIELD(AFE4403_TIAGAIN, 0, 2),
  51         [F_CF_LED1]     = REG_FIELD(AFE4403_TIAGAIN, 3, 7),
  52         [F_RF_LED]      = REG_FIELD(AFE4403_TIA_AMB_GAIN, 0, 2),
  53         [F_CF_LED]      = REG_FIELD(AFE4403_TIA_AMB_GAIN, 3, 7),
  54         /* LED Current */
  55         [F_ILED1]       = REG_FIELD(AFE440X_LEDCNTRL, 0, 7),
  56         [F_ILED2]       = REG_FIELD(AFE440X_LEDCNTRL, 8, 15),
  57 };
  58
  59 /**
  60  * struct afe4403_data - AFE4403 device instance data
  61  * @dev: Device structure
  62  * @spi: SPI device handle
  63  * @regmap: Register map of the device
  64  * @fields: Register fields of the device
  65  * @regulator: Pointer to the regulator for the IC
  66  * @trig: IIO trigger for this device
  67  * @irq: ADC_RDY line interrupt number
  68  * @buffer: Used to construct data layout to push into IIO buffer.
  69  */
  70 struct afe4403_data {
  71         struct device *dev;
  72         struct spi_device *spi;
  73         struct regmap *regmap;
  74         struct regmap_field *fields[F_MAX_FIELDS];
  75         struct regulator *regulator;
  76         struct iio_trigger *trig;
  77         int irq;
  78         /* Ensure suitable alignment for timestamp */
  79         s32 buffer[8] __aligned(8);
  80 };
  81
  82 enum afe4403_chan_id {
  83         LED2 = 1,
  84         ALED2,
  85         LED1,
  86         ALED1,
  87         LED2_ALED2,
  88         LED1_ALED1,
  89 };
  90
  91 static const unsigned int afe4403_channel_values[] = {
  92         [LED2] = AFE440X_LED2VAL,
  93         [ALED2] = AFE440X_ALED2VAL,
  94         [LED1] = AFE440X_LED1VAL,
  95         [ALED1] = AFE440X_ALED1VAL,
  96         [LED2_ALED2] = AFE440X_LED2_ALED2VAL,
  97         [LED1_ALED1] = AFE440X_LED1_ALED1VAL,
  98 };
  99
 100 static const unsigned int afe4403_channel_leds[] = {
 101         [LED2] = F_ILED2,
 102         [LED1] = F_ILED1,
 103 };
 104
 105 static const struct iio_chan_spec afe4403_channels[] = {
 106         /* ADC values */
 107         AFE440X_INTENSITY_CHAN(LED2, 0),
 108         AFE440X_INTENSITY_CHAN(ALED2, 0),
 109         AFE440X_INTENSITY_CHAN(LED1, 0),
 110         AFE440X_INTENSITY_CHAN(ALED1, 0),
 111         AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
 112         AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
 113         /* LED current */
 114         AFE440X_CURRENT_CHAN(LED2),
 115         AFE440X_CURRENT_CHAN(LED1),
 116 };
 117
 118 static const struct afe440x_val_table afe4403_res_table[] = {
 119         { 500000 }, { 250000 }, { 100000 }, { 50000 },
 120         { 25000 }, { 10000 }, { 1000000 }, { 0 },
 121 };
 122 AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4403_res_table);
 123
 124 static const struct afe440x_val_table afe4403_cap_table[] = {
 125         { 0, 5000 }, { 0, 10000 }, { 0, 20000 }, { 0, 25000 },
 126         { 0, 30000 }, { 0, 35000 }, { 0, 45000 }, { 0, 50000 },
 127         { 0, 55000 }, { 0, 60000 }, { 0, 70000 }, { 0, 75000 },
 128         { 0, 80000 }, { 0, 85000 }, { 0, 95000 }, { 0, 100000 },
 129         { 0, 155000 }, { 0, 160000 }, { 0, 170000 }, { 0, 175000 },
 130         { 0, 180000 }, { 0, 185000 }, { 0, 195000 }, { 0, 200000 },
 131         { 0, 205000 }, { 0, 210000 }, { 0, 220000 }, { 0, 225000 },
 132         { 0, 230000 }, { 0, 235000 }, { 0, 245000 }, { 0, 250000 },
 133 };
 134 AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4403_cap_table);
 135
 136 static ssize_t afe440x_show_register(struct device *dev,
 137                                      struct device_attribute *attr,
 138                                      char *buf)
 139 {
 140         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 141         struct afe4403_data *afe = iio_priv(indio_dev);
 142         struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
 143         unsigned int reg_val;
 144         int vals[2];
 145         int ret;
 146
 147         ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
 148         if (ret)
 149                 return ret;
 150
 151         if (reg_val >= afe440x_attr->table_size)
 152                 return -EINVAL;
 153
 154         vals[0] = afe440x_attr->val_table[reg_val].integer;
 155         vals[1] = afe440x_attr->val_table[reg_val].fract;
 156
 157         return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
 158 }
 159
 160 static ssize_t afe440x_store_register(struct device *dev,
 161                                       struct device_attribute *attr,
 162                                       const char *buf, size_t count)
 163 {
 164         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 165         struct afe4403_data *afe = iio_priv(indio_dev);
 166         struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
 167         int val, integer, fract, ret;
 168
 169         ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
 170         if (ret)
 171                 return ret;
 172
 173         for (val = 0; val < afe440x_attr->table_size; val++)
 174                 if (afe440x_attr->val_table[val].integer == integer &&
 175                     afe440x_attr->val_table[val].fract == fract)
 176                         break;
 177         if (val == afe440x_attr->table_size)
 178                 return -EINVAL;
 179
 180         ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
 181         if (ret)
 182                 return ret;
 183
 184         return count;
 185 }
 186
 187 static AFE440X_ATTR(in_intensity1_resistance, F_RF_LED, afe4403_res_table);
 188 static AFE440X_ATTR(in_intensity1_capacitance, F_CF_LED, afe4403_cap_table);
 189
 190 static AFE440X_ATTR(in_intensity2_resistance, F_RF_LED, afe4403_res_table);
 191 static AFE440X_ATTR(in_intensity2_capacitance, F_CF_LED, afe4403_cap_table);
 192
 193 static AFE440X_ATTR(in_intensity3_resistance, F_RF_LED1, afe4403_res_table);
 194 static AFE440X_ATTR(in_intensity3_capacitance, F_CF_LED1, afe4403_cap_table);
 195
 196 static AFE440X_ATTR(in_intensity4_resistance, F_RF_LED1, afe4403_res_table);
 197 static AFE440X_ATTR(in_intensity4_capacitance, F_CF_LED1, afe4403_cap_table);
 198
 199 static struct attribute *afe440x_attributes[] = {
 200         &dev_attr_in_intensity_resistance_available.attr,
 201         &dev_attr_in_intensity_capacitance_available.attr,
 202         &afe440x_attr_in_intensity1_resistance.dev_attr.attr,
 203         &afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
 204         &afe440x_attr_in_intensity2_resistance.dev_attr.attr,
 205         &afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
 206         &afe440x_attr_in_intensity3_resistance.dev_attr.attr,
 207         &afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
 208         &afe440x_attr_in_intensity4_resistance.dev_attr.attr,
 209         &afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
 210         NULL
 211 };
 212
 213 static const struct attribute_group afe440x_attribute_group = {
 214         .attrs = afe440x_attributes
 215 };
 216
 217 static int afe4403_read(struct afe4403_data *afe, unsigned int reg, u32 *val)
 218 {
 219         u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
 220         u8 rx[3];
 221         int ret;
 222
 223         /* Enable reading from the device */
 224         ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
 225         if (ret)
 226                 return ret;
 227
 228         ret = spi_write_then_read(afe->spi, &reg, 1, rx, sizeof(rx));
 229         if (ret)
 230                 return ret;
 231
 232         *val = get_unaligned_be24(&rx[0]);
 233
 234         /* Disable reading from the device */
 235         tx[3] = AFE440X_CONTROL0_WRITE;
 236         ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
 237         if (ret)
 238                 return ret;
 239
 240         return 0;
 241 }
 242
 243 static int afe4403_read_raw(struct iio_dev *indio_dev,
 244                             struct iio_chan_spec const *chan,
 245                             int *val, int *val2, long mask)
 246 {
 247         struct afe4403_data *afe = iio_priv(indio_dev);
 248         unsigned int reg = afe4403_channel_values[chan->address];
 249         unsigned int field = afe4403_channel_leds[chan->address];
 250         int ret;
 251
 252         switch (chan->type) {
 253         case IIO_INTENSITY:
 254                 switch (mask) {
 255                 case IIO_CHAN_INFO_RAW:
 256                         ret = afe4403_read(afe, reg, val);
 257                         if (ret)
 258                                 return ret;
 259                         return IIO_VAL_INT;
 260                 }
 261                 break;
 262         case IIO_CURRENT:
 263                 switch (mask) {
 264                 case IIO_CHAN_INFO_RAW:
 265                         ret = regmap_field_read(afe->fields[field], val);
 266                         if (ret)
 267                                 return ret;
 268                         return IIO_VAL_INT;
 269                 case IIO_CHAN_INFO_SCALE:
 270                         *val = 0;
 271                         *val2 = 800000;
 272                         return IIO_VAL_INT_PLUS_MICRO;
 273                 }
 274                 break;
 275         default:
 276                 break;
 277         }
 278
 279         return -EINVAL;
 280 }
 281
 282 static int afe4403_write_raw(struct iio_dev *indio_dev,
 283                              struct iio_chan_spec const *chan,
 284                              int val, int val2, long mask)
 285 {
 286         struct afe4403_data *afe = iio_priv(indio_dev);
 287         unsigned int field = afe4403_channel_leds[chan->address];
 288
 289         switch (chan->type) {
 290         case IIO_CURRENT:
 291                 switch (mask) {
 292                 case IIO_CHAN_INFO_RAW:
 293                         return regmap_field_write(afe->fields[field], val);
 294                 }
 295                 break;
 296         default:
 297                 break;
 298         }
 299
 300         return -EINVAL;
 301 }
 302
 303 static const struct iio_info afe4403_iio_info = {
 304         .attrs = &afe440x_attribute_group,
 305         .read_raw = afe4403_read_raw,
 306         .write_raw = afe4403_write_raw,
 307 };
 308
 309 static irqreturn_t afe4403_trigger_handler(int irq, void *private)
 310 {
 311         struct iio_poll_func *pf = private;
 312         struct iio_dev *indio_dev = pf->indio_dev;
 313         struct afe4403_data *afe = iio_priv(indio_dev);
 314         int ret, bit, i = 0;
 315         u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ};
 316         u8 rx[3];
 317
 318         /* Enable reading from the device */
 319         ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
 320         if (ret)
 321                 goto err;
 322
 323         for_each_set_bit(bit, indio_dev->active_scan_mask,
 324                          indio_dev->masklength) {
 325                 ret = spi_write_then_read(afe->spi,
 326                                           &afe4403_channel_values[bit], 1,
 327                                           rx, sizeof(rx));
 328                 if (ret)
 329                         goto err;
 330
 331                 afe->buffer[i++] = get_unaligned_be24(&rx[0]);
 332         }
 333
 334         /* Disable reading from the device */
 335         tx[3] = AFE440X_CONTROL0_WRITE;
 336         ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0);
 337         if (ret)
 338                 goto err;
 339
 340         iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
 341                                            pf->timestamp);
 342 err:
 343         iio_trigger_notify_done(indio_dev->trig);
 344
 345         return IRQ_HANDLED;
 346 }
 347
 348 #define AFE4403_TIMING_PAIRS                    \
 349         { AFE440X_LED2STC,      0x000050 },     \
 350         { AFE440X_LED2ENDC,     0x0003e7 },     \
 351         { AFE440X_LED1LEDSTC,   0x0007d0 },     \
 352         { AFE440X_LED1LEDENDC,  0x000bb7 },     \
 353         { AFE440X_ALED2STC,     0x000438 },     \
 354         { AFE440X_ALED2ENDC,    0x0007cf },     \
 355         { AFE440X_LED1STC,      0x000820 },     \
 356         { AFE440X_LED1ENDC,     0x000bb7 },     \
 357         { AFE440X_LED2LEDSTC,   0x000000 },     \
 358         { AFE440X_LED2LEDENDC,  0x0003e7 },     \
 359         { AFE440X_ALED1STC,     0x000c08 },     \
 360         { AFE440X_ALED1ENDC,    0x000f9f },     \
 361         { AFE440X_LED2CONVST,   0x0003ef },     \
 362         { AFE440X_LED2CONVEND,  0x0007cf },     \
 363         { AFE440X_ALED2CONVST,  0x0007d7 },     \
 364         { AFE440X_ALED2CONVEND, 0x000bb7 },     \
 365         { AFE440X_LED1CONVST,   0x000bbf },     \
 366         { AFE440X_LED1CONVEND,  0x009c3f },     \
 367         { AFE440X_ALED1CONVST,  0x000fa7 },     \
 368         { AFE440X_ALED1CONVEND, 0x001387 },     \
 369         { AFE440X_ADCRSTSTCT0,  0x0003e8 },     \
 370         { AFE440X_ADCRSTENDCT0, 0x0003eb },     \
 371         { AFE440X_ADCRSTSTCT1,  0x0007d0 },     \
 372         { AFE440X_ADCRSTENDCT1, 0x0007d3 },     \
 373         { AFE440X_ADCRSTSTCT2,  0x000bb8 },     \
 374         { AFE440X_ADCRSTENDCT2, 0x000bbb },     \
 375         { AFE440X_ADCRSTSTCT3,  0x000fa0 },     \
 376         { AFE440X_ADCRSTENDCT3, 0x000fa3 },     \
 377         { AFE440X_PRPCOUNT,     0x009c3f },     \
 378         { AFE440X_PDNCYCLESTC,  0x001518 },     \
 379         { AFE440X_PDNCYCLEENDC, 0x00991f }
 380
 381 static const struct reg_sequence afe4403_reg_sequences[] = {
 382         AFE4403_TIMING_PAIRS,
 383         { AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
 384         { AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN },
 385 };
 386
 387 static const struct regmap_range afe4403_yes_ranges[] = {
 388         regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
 389 };
 390
 391 static const struct regmap_access_table afe4403_volatile_table = {
 392         .yes_ranges = afe4403_yes_ranges,
 393         .n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges),
 394 };
 395
 396 static const struct regmap_config afe4403_regmap_config = {
 397         .reg_bits = 8,
 398         .val_bits = 24,
 399
 400         .max_register = AFE440X_PDNCYCLEENDC,
 401         .cache_type = REGCACHE_RBTREE,
 402         .volatile_table = &afe4403_volatile_table,
 403 };
 404
 405 static const struct of_device_id afe4403_of_match[] = {
 406         { .compatible = "ti,afe4403", },
 407         { /* sentinel */ }
 408 };
 409 MODULE_DEVICE_TABLE(of, afe4403_of_match);
 410
 411 static int __maybe_unused afe4403_suspend(struct device *dev)
 412 {
 413         struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
 414         struct afe4403_data *afe = iio_priv(indio_dev);
 415         int ret;
 416
 417         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
 418                                  AFE440X_CONTROL2_PDN_AFE,
 419                                  AFE440X_CONTROL2_PDN_AFE);
 420         if (ret)
 421                 return ret;
 422
 423         ret = regulator_disable(afe->regulator);
 424         if (ret) {
 425                 dev_err(dev, "Unable to disable regulator\n");
 426                 return ret;
 427         }
 428
 429         return 0;
 430 }
 431
 432 static int __maybe_unused afe4403_resume(struct device *dev)
 433 {
 434         struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev));
 435         struct afe4403_data *afe = iio_priv(indio_dev);
 436         int ret;
 437
 438         ret = regulator_enable(afe->regulator);
 439         if (ret) {
 440                 dev_err(dev, "Unable to enable regulator\n");
 441                 return ret;
 442         }
 443
 444         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
 445                                  AFE440X_CONTROL2_PDN_AFE, 0);
 446         if (ret)
 447                 return ret;
 448
 449         return 0;
 450 }
 451
 452 static SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, afe4403_resume);
 453
 454 static int afe4403_probe(struct spi_device *spi)
 455 {
 456         struct iio_dev *indio_dev;
 457         struct afe4403_data *afe;
 458         int i, ret;
 459
 460         indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe));
 461         if (!indio_dev)
 462                 return -ENOMEM;
 463
 464         afe = iio_priv(indio_dev);
 465         spi_set_drvdata(spi, indio_dev);
 466
 467         afe->dev = &spi->dev;
 468         afe->spi = spi;
 469         afe->irq = spi->irq;
 470
 471         afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config);
 472         if (IS_ERR(afe->regmap)) {
 473                 dev_err(afe->dev, "Unable to allocate register map\n");
 474                 return PTR_ERR(afe->regmap);
 475         }
 476
 477         for (i = 0; i < F_MAX_FIELDS; i++) {
 478                 afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
 479                                                          afe4403_reg_fields[i]);
 480                 if (IS_ERR(afe->fields[i])) {
 481                         dev_err(afe->dev, "Unable to allocate regmap fields\n");
 482                         return PTR_ERR(afe->fields[i]);
 483                 }
 484         }
 485
 486         afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
 487         if (IS_ERR(afe->regulator))
 488                 return dev_err_probe(afe->dev, PTR_ERR(afe->regulator),
 489                                      "Unable to get regulator\n");
 490
 491         ret = regulator_enable(afe->regulator);
 492         if (ret) {
 493                 dev_err(afe->dev, "Unable to enable regulator\n");
 494                 return ret;
 495         }
 496
 497         ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
 498                            AFE440X_CONTROL0_SW_RESET);
 499         if (ret) {
 500                 dev_err(afe->dev, "Unable to reset device\n");
 501                 goto err_disable_reg;
 502         }
 503
 504         ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences,
 505                                      ARRAY_SIZE(afe4403_reg_sequences));
 506         if (ret) {
 507                 dev_err(afe->dev, "Unable to set register defaults\n");
 508                 goto err_disable_reg;
 509         }
 510
 511         indio_dev->modes = INDIO_DIRECT_MODE;
 512         indio_dev->channels = afe4403_channels;
 513         indio_dev->num_channels = ARRAY_SIZE(afe4403_channels);
 514         indio_dev->name = AFE4403_DRIVER_NAME;
 515         indio_dev->info = &afe4403_iio_info;
 516
 517         if (afe->irq > 0) {
 518                 afe->trig = devm_iio_trigger_alloc(afe->dev,
 519                                                    "%s-dev%d",
 520                                                    indio_dev->name,
 521                                                    iio_device_id(indio_dev));
 522                 if (!afe->trig) {
 523                         dev_err(afe->dev, "Unable to allocate IIO trigger\n");
 524                         ret = -ENOMEM;
 525                         goto err_disable_reg;
 526                 }
 527
 528                 iio_trigger_set_drvdata(afe->trig, indio_dev);
 529
 530                 ret = iio_trigger_register(afe->trig);
 531                 if (ret) {
 532                         dev_err(afe->dev, "Unable to register IIO trigger\n");
 533                         goto err_disable_reg;
 534                 }
 535
 536                 ret = devm_request_threaded_irq(afe->dev, afe->irq,
 537                                                 iio_trigger_generic_data_rdy_poll,
 538                                                 NULL, IRQF_ONESHOT,
 539                                                 AFE4403_DRIVER_NAME,
 540                                                 afe->trig);
 541                 if (ret) {
 542                         dev_err(afe->dev, "Unable to request IRQ\n");
 543                         goto err_trig;
 544                 }
 545         }
 546
 547         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 548                                          afe4403_trigger_handler, NULL);
 549         if (ret) {
 550                 dev_err(afe->dev, "Unable to setup buffer\n");
 551                 goto err_trig;
 552         }
 553
 554         ret = iio_device_register(indio_dev);
 555         if (ret) {
 556                 dev_err(afe->dev, "Unable to register IIO device\n");
 557                 goto err_buff;
 558         }
 559
 560         return 0;
 561
 562 err_buff:
 563         iio_triggered_buffer_cleanup(indio_dev);
 564 err_trig:
 565         if (afe->irq > 0)
 566                 iio_trigger_unregister(afe->trig);
 567 err_disable_reg:
 568         regulator_disable(afe->regulator);
 569
 570         return ret;
 571 }
 572
 573 static void afe4403_remove(struct spi_device *spi)
 574 {
 575         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 576         struct afe4403_data *afe = iio_priv(indio_dev);
 577         int ret;
 578
 579         iio_device_unregister(indio_dev);
 580
 581         iio_triggered_buffer_cleanup(indio_dev);
 582
 583         if (afe->irq > 0)
 584                 iio_trigger_unregister(afe->trig);
 585
 586         ret = regulator_disable(afe->regulator);
 587         if (ret)
 588                 dev_warn(afe->dev, "Unable to disable regulator\n");
 589 }
 590
 591 static const struct spi_device_id afe4403_ids[] = {
 592         { "afe4403", 0 },
 593         { /* sentinel */ }
 594 };
 595 MODULE_DEVICE_TABLE(spi, afe4403_ids);
 596
 597 static struct spi_driver afe4403_spi_driver = {
 598         .driver = {
 599                 .name = AFE4403_DRIVER_NAME,
 600                 .of_match_table = afe4403_of_match,
 601                 .pm = &afe4403_pm_ops,
 602         },
 603         .probe = afe4403_probe,
 604         .remove = afe4403_remove,
 605         .id_table = afe4403_ids,
 606 };
 607 module_spi_driver(afe4403_spi_driver);
 608
 609 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
 610 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE");
 611 MODULE_LICENSE("GPL v2");