drivers/iio/health/afe4404.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * AFE4404 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/i2c.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/regmap.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 "afe440x.h"
  27
  28 #define AFE4404_DRIVER_NAME             "afe4404"
  29
  30 /* AFE4404 registers */
  31 #define AFE4404_TIA_GAIN_SEP            0x20
  32 #define AFE4404_TIA_GAIN                0x21
  33 #define AFE4404_PROG_TG_STC             0x34
  34 #define AFE4404_PROG_TG_ENDC            0x35
  35 #define AFE4404_LED3LEDSTC              0x36
  36 #define AFE4404_LED3LEDENDC             0x37
  37 #define AFE4404_CLKDIV_PRF              0x39
  38 #define AFE4404_OFFDAC                  0x3a
  39 #define AFE4404_DEC                     0x3d
  40 #define AFE4404_AVG_LED2_ALED2VAL       0x3f
  41 #define AFE4404_AVG_LED1_ALED1VAL       0x40
  42
  43 /* AFE4404 CONTROL2 register fields */
  44 #define AFE440X_CONTROL2_OSC_ENABLE     BIT(9)
  45
  46 enum afe4404_fields {
  47         /* Gains */
  48         F_TIA_GAIN_SEP, F_TIA_CF_SEP,
  49         F_TIA_GAIN, TIA_CF,
  50
  51         /* LED Current */
  52         F_ILED1, F_ILED2, F_ILED3,
  53
  54         /* Offset DAC */
  55         F_OFFDAC_AMB2, F_OFFDAC_LED1, F_OFFDAC_AMB1, F_OFFDAC_LED2,
  56
  57         /* sentinel */
  58         F_MAX_FIELDS
  59 };
  60
  61 static const struct reg_field afe4404_reg_fields[] = {
  62         /* Gains */
  63         [F_TIA_GAIN_SEP]        = REG_FIELD(AFE4404_TIA_GAIN_SEP, 0, 2),
  64         [F_TIA_CF_SEP]          = REG_FIELD(AFE4404_TIA_GAIN_SEP, 3, 5),
  65         [F_TIA_GAIN]            = REG_FIELD(AFE4404_TIA_GAIN, 0, 2),
  66         [TIA_CF]                = REG_FIELD(AFE4404_TIA_GAIN, 3, 5),
  67         /* LED Current */
  68         [F_ILED1]               = REG_FIELD(AFE440X_LEDCNTRL, 0, 5),
  69         [F_ILED2]               = REG_FIELD(AFE440X_LEDCNTRL, 6, 11),
  70         [F_ILED3]               = REG_FIELD(AFE440X_LEDCNTRL, 12, 17),
  71         /* Offset DAC */
  72         [F_OFFDAC_AMB2]         = REG_FIELD(AFE4404_OFFDAC, 0, 4),
  73         [F_OFFDAC_LED1]         = REG_FIELD(AFE4404_OFFDAC, 5, 9),
  74         [F_OFFDAC_AMB1]         = REG_FIELD(AFE4404_OFFDAC, 10, 14),
  75         [F_OFFDAC_LED2]         = REG_FIELD(AFE4404_OFFDAC, 15, 19),
  76 };
  77
  78 /**
  79  * struct afe4404_data - AFE4404 device instance data
  80  * @dev: Device structure
  81  * @regmap: Register map of the device
  82  * @fields: Register fields of the device
  83  * @regulator: Pointer to the regulator for the IC
  84  * @trig: IIO trigger for this device
  85  * @irq: ADC_RDY line interrupt number
  86  * @buffer: Used to construct a scan to push to the iio buffer.
  87  */
  88 struct afe4404_data {
  89         struct device *dev;
  90         struct regmap *regmap;
  91         struct regmap_field *fields[F_MAX_FIELDS];
  92         struct regulator *regulator;
  93         struct iio_trigger *trig;
  94         int irq;
  95         s32 buffer[10] __aligned(8);
  96 };
  97
  98 enum afe4404_chan_id {
  99         LED2 = 1,
 100         ALED2,
 101         LED1,
 102         ALED1,
 103         LED2_ALED2,
 104         LED1_ALED1,
 105 };
 106
 107 static const unsigned int afe4404_channel_values[] = {
 108         [LED2] = AFE440X_LED2VAL,
 109         [ALED2] = AFE440X_ALED2VAL,
 110         [LED1] = AFE440X_LED1VAL,
 111         [ALED1] = AFE440X_ALED1VAL,
 112         [LED2_ALED2] = AFE440X_LED2_ALED2VAL,
 113         [LED1_ALED1] = AFE440X_LED1_ALED1VAL,
 114 };
 115
 116 static const unsigned int afe4404_channel_leds[] = {
 117         [LED2] = F_ILED2,
 118         [ALED2] = F_ILED3,
 119         [LED1] = F_ILED1,
 120 };
 121
 122 static const unsigned int afe4404_channel_offdacs[] = {
 123         [LED2] = F_OFFDAC_LED2,
 124         [ALED2] = F_OFFDAC_AMB2,
 125         [LED1] = F_OFFDAC_LED1,
 126         [ALED1] = F_OFFDAC_AMB1,
 127 };
 128
 129 static const struct iio_chan_spec afe4404_channels[] = {
 130         /* ADC values */
 131         AFE440X_INTENSITY_CHAN(LED2, BIT(IIO_CHAN_INFO_OFFSET)),
 132         AFE440X_INTENSITY_CHAN(ALED2, BIT(IIO_CHAN_INFO_OFFSET)),
 133         AFE440X_INTENSITY_CHAN(LED1, BIT(IIO_CHAN_INFO_OFFSET)),
 134         AFE440X_INTENSITY_CHAN(ALED1, BIT(IIO_CHAN_INFO_OFFSET)),
 135         AFE440X_INTENSITY_CHAN(LED2_ALED2, 0),
 136         AFE440X_INTENSITY_CHAN(LED1_ALED1, 0),
 137         /* LED current */
 138         AFE440X_CURRENT_CHAN(LED2),
 139         AFE440X_CURRENT_CHAN(ALED2),
 140         AFE440X_CURRENT_CHAN(LED1),
 141 };
 142
 143 static const struct afe440x_val_table afe4404_res_table[] = {
 144         { .integer = 500000, .fract = 0 },
 145         { .integer = 250000, .fract = 0 },
 146         { .integer = 100000, .fract = 0 },
 147         { .integer = 50000, .fract = 0 },
 148         { .integer = 25000, .fract = 0 },
 149         { .integer = 10000, .fract = 0 },
 150         { .integer = 1000000, .fract = 0 },
 151         { .integer = 2000000, .fract = 0 },
 152 };
 153 AFE440X_TABLE_ATTR(in_intensity_resistance_available, afe4404_res_table);
 154
 155 static const struct afe440x_val_table afe4404_cap_table[] = {
 156         { .integer = 0, .fract = 5000 },
 157         { .integer = 0, .fract = 2500 },
 158         { .integer = 0, .fract = 10000 },
 159         { .integer = 0, .fract = 7500 },
 160         { .integer = 0, .fract = 20000 },
 161         { .integer = 0, .fract = 17500 },
 162         { .integer = 0, .fract = 25000 },
 163         { .integer = 0, .fract = 22500 },
 164 };
 165 AFE440X_TABLE_ATTR(in_intensity_capacitance_available, afe4404_cap_table);
 166
 167 static ssize_t afe440x_show_register(struct device *dev,
 168                                      struct device_attribute *attr,
 169                                      char *buf)
 170 {
 171         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 172         struct afe4404_data *afe = iio_priv(indio_dev);
 173         struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
 174         unsigned int reg_val;
 175         int vals[2];
 176         int ret;
 177
 178         ret = regmap_field_read(afe->fields[afe440x_attr->field], &reg_val);
 179         if (ret)
 180                 return ret;
 181
 182         if (reg_val >= afe440x_attr->table_size)
 183                 return -EINVAL;
 184
 185         vals[0] = afe440x_attr->val_table[reg_val].integer;
 186         vals[1] = afe440x_attr->val_table[reg_val].fract;
 187
 188         return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
 189 }
 190
 191 static ssize_t afe440x_store_register(struct device *dev,
 192                                       struct device_attribute *attr,
 193                                       const char *buf, size_t count)
 194 {
 195         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 196         struct afe4404_data *afe = iio_priv(indio_dev);
 197         struct afe440x_attr *afe440x_attr = to_afe440x_attr(attr);
 198         int val, integer, fract, ret;
 199
 200         ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
 201         if (ret)
 202                 return ret;
 203
 204         for (val = 0; val < afe440x_attr->table_size; val++)
 205                 if (afe440x_attr->val_table[val].integer == integer &&
 206                     afe440x_attr->val_table[val].fract == fract)
 207                         break;
 208         if (val == afe440x_attr->table_size)
 209                 return -EINVAL;
 210
 211         ret = regmap_field_write(afe->fields[afe440x_attr->field], val);
 212         if (ret)
 213                 return ret;
 214
 215         return count;
 216 }
 217
 218 static AFE440X_ATTR(in_intensity1_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
 219 static AFE440X_ATTR(in_intensity1_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
 220
 221 static AFE440X_ATTR(in_intensity2_resistance, F_TIA_GAIN_SEP, afe4404_res_table);
 222 static AFE440X_ATTR(in_intensity2_capacitance, F_TIA_CF_SEP, afe4404_cap_table);
 223
 224 static AFE440X_ATTR(in_intensity3_resistance, F_TIA_GAIN, afe4404_res_table);
 225 static AFE440X_ATTR(in_intensity3_capacitance, TIA_CF, afe4404_cap_table);
 226
 227 static AFE440X_ATTR(in_intensity4_resistance, F_TIA_GAIN, afe4404_res_table);
 228 static AFE440X_ATTR(in_intensity4_capacitance, TIA_CF, afe4404_cap_table);
 229
 230 static struct attribute *afe440x_attributes[] = {
 231         &dev_attr_in_intensity_resistance_available.attr,
 232         &dev_attr_in_intensity_capacitance_available.attr,
 233         &afe440x_attr_in_intensity1_resistance.dev_attr.attr,
 234         &afe440x_attr_in_intensity1_capacitance.dev_attr.attr,
 235         &afe440x_attr_in_intensity2_resistance.dev_attr.attr,
 236         &afe440x_attr_in_intensity2_capacitance.dev_attr.attr,
 237         &afe440x_attr_in_intensity3_resistance.dev_attr.attr,
 238         &afe440x_attr_in_intensity3_capacitance.dev_attr.attr,
 239         &afe440x_attr_in_intensity4_resistance.dev_attr.attr,
 240         &afe440x_attr_in_intensity4_capacitance.dev_attr.attr,
 241         NULL
 242 };
 243
 244 static const struct attribute_group afe440x_attribute_group = {
 245         .attrs = afe440x_attributes
 246 };
 247
 248 static int afe4404_read_raw(struct iio_dev *indio_dev,
 249                             struct iio_chan_spec const *chan,
 250                             int *val, int *val2, long mask)
 251 {
 252         struct afe4404_data *afe = iio_priv(indio_dev);
 253         unsigned int value_reg = afe4404_channel_values[chan->address];
 254         unsigned int led_field = afe4404_channel_leds[chan->address];
 255         unsigned int offdac_field = afe4404_channel_offdacs[chan->address];
 256         int ret;
 257
 258         switch (chan->type) {
 259         case IIO_INTENSITY:
 260                 switch (mask) {
 261                 case IIO_CHAN_INFO_RAW:
 262                         ret = regmap_read(afe->regmap, value_reg, val);
 263                         if (ret)
 264                                 return ret;
 265                         return IIO_VAL_INT;
 266                 case IIO_CHAN_INFO_OFFSET:
 267                         ret = regmap_field_read(afe->fields[offdac_field], val);
 268                         if (ret)
 269                                 return ret;
 270                         return IIO_VAL_INT;
 271                 }
 272                 break;
 273         case IIO_CURRENT:
 274                 switch (mask) {
 275                 case IIO_CHAN_INFO_RAW:
 276                         ret = regmap_field_read(afe->fields[led_field], val);
 277                         if (ret)
 278                                 return ret;
 279                         return IIO_VAL_INT;
 280                 case IIO_CHAN_INFO_SCALE:
 281                         *val = 0;
 282                         *val2 = 800000;
 283                         return IIO_VAL_INT_PLUS_MICRO;
 284                 }
 285                 break;
 286         default:
 287                 break;
 288         }
 289
 290         return -EINVAL;
 291 }
 292
 293 static int afe4404_write_raw(struct iio_dev *indio_dev,
 294                              struct iio_chan_spec const *chan,
 295                              int val, int val2, long mask)
 296 {
 297         struct afe4404_data *afe = iio_priv(indio_dev);
 298         unsigned int led_field = afe4404_channel_leds[chan->address];
 299         unsigned int offdac_field = afe4404_channel_offdacs[chan->address];
 300
 301         switch (chan->type) {
 302         case IIO_INTENSITY:
 303                 switch (mask) {
 304                 case IIO_CHAN_INFO_OFFSET:
 305                         return regmap_field_write(afe->fields[offdac_field], val);
 306                 }
 307                 break;
 308         case IIO_CURRENT:
 309                 switch (mask) {
 310                 case IIO_CHAN_INFO_RAW:
 311                         return regmap_field_write(afe->fields[led_field], val);
 312                 }
 313                 break;
 314         default:
 315                 break;
 316         }
 317
 318         return -EINVAL;
 319 }
 320
 321 static const struct iio_info afe4404_iio_info = {
 322         .attrs = &afe440x_attribute_group,
 323         .read_raw = afe4404_read_raw,
 324         .write_raw = afe4404_write_raw,
 325 };
 326
 327 static irqreturn_t afe4404_trigger_handler(int irq, void *private)
 328 {
 329         struct iio_poll_func *pf = private;
 330         struct iio_dev *indio_dev = pf->indio_dev;
 331         struct afe4404_data *afe = iio_priv(indio_dev);
 332         int ret, bit, i = 0;
 333
 334         for_each_set_bit(bit, indio_dev->active_scan_mask,
 335                          indio_dev->masklength) {
 336                 ret = regmap_read(afe->regmap, afe4404_channel_values[bit],
 337                                   &afe->buffer[i++]);
 338                 if (ret)
 339                         goto err;
 340         }
 341
 342         iio_push_to_buffers_with_timestamp(indio_dev, afe->buffer,
 343                                            pf->timestamp);
 344 err:
 345         iio_trigger_notify_done(indio_dev->trig);
 346
 347         return IRQ_HANDLED;
 348 }
 349
 350 static const struct iio_trigger_ops afe4404_trigger_ops = {
 351 };
 352
 353 /* Default timings from data-sheet */
 354 #define AFE4404_TIMING_PAIRS                    \
 355         { AFE440X_PRPCOUNT,     39999   },      \
 356         { AFE440X_LED2LEDSTC,   0       },      \
 357         { AFE440X_LED2LEDENDC,  398     },      \
 358         { AFE440X_LED2STC,      80      },      \
 359         { AFE440X_LED2ENDC,     398     },      \
 360         { AFE440X_ADCRSTSTCT0,  5600    },      \
 361         { AFE440X_ADCRSTENDCT0, 5606    },      \
 362         { AFE440X_LED2CONVST,   5607    },      \
 363         { AFE440X_LED2CONVEND,  6066    },      \
 364         { AFE4404_LED3LEDSTC,   400     },      \
 365         { AFE4404_LED3LEDENDC,  798     },      \
 366         { AFE440X_ALED2STC,     480     },      \
 367         { AFE440X_ALED2ENDC,    798     },      \
 368         { AFE440X_ADCRSTSTCT1,  6068    },      \
 369         { AFE440X_ADCRSTENDCT1, 6074    },      \
 370         { AFE440X_ALED2CONVST,  6075    },      \
 371         { AFE440X_ALED2CONVEND, 6534    },      \
 372         { AFE440X_LED1LEDSTC,   800     },      \
 373         { AFE440X_LED1LEDENDC,  1198    },      \
 374         { AFE440X_LED1STC,      880     },      \
 375         { AFE440X_LED1ENDC,     1198    },      \
 376         { AFE440X_ADCRSTSTCT2,  6536    },      \
 377         { AFE440X_ADCRSTENDCT2, 6542    },      \
 378         { AFE440X_LED1CONVST,   6543    },      \
 379         { AFE440X_LED1CONVEND,  7003    },      \
 380         { AFE440X_ALED1STC,     1280    },      \
 381         { AFE440X_ALED1ENDC,    1598    },      \
 382         { AFE440X_ADCRSTSTCT3,  7005    },      \
 383         { AFE440X_ADCRSTENDCT3, 7011    },      \
 384         { AFE440X_ALED1CONVST,  7012    },      \
 385         { AFE440X_ALED1CONVEND, 7471    },      \
 386         { AFE440X_PDNCYCLESTC,  7671    },      \
 387         { AFE440X_PDNCYCLEENDC, 39199   }
 388
 389 static const struct reg_sequence afe4404_reg_sequences[] = {
 390         AFE4404_TIMING_PAIRS,
 391         { AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN },
 392         { AFE4404_TIA_GAIN_SEP, AFE440X_TIAGAIN_ENSEPGAIN },
 393         { AFE440X_CONTROL2, AFE440X_CONTROL2_OSC_ENABLE },
 394 };
 395
 396 static const struct regmap_range afe4404_yes_ranges[] = {
 397         regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL),
 398         regmap_reg_range(AFE4404_AVG_LED2_ALED2VAL, AFE4404_AVG_LED1_ALED1VAL),
 399 };
 400
 401 static const struct regmap_access_table afe4404_volatile_table = {
 402         .yes_ranges = afe4404_yes_ranges,
 403         .n_yes_ranges = ARRAY_SIZE(afe4404_yes_ranges),
 404 };
 405
 406 static const struct regmap_config afe4404_regmap_config = {
 407         .reg_bits = 8,
 408         .val_bits = 24,
 409
 410         .max_register = AFE4404_AVG_LED1_ALED1VAL,
 411         .cache_type = REGCACHE_RBTREE,
 412         .volatile_table = &afe4404_volatile_table,
 413 };
 414
 415 static const struct of_device_id afe4404_of_match[] = {
 416         { .compatible = "ti,afe4404", },
 417         { /* sentinel */ }
 418 };
 419 MODULE_DEVICE_TABLE(of, afe4404_of_match);
 420
 421 static int __maybe_unused afe4404_suspend(struct device *dev)
 422 {
 423         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 424         struct afe4404_data *afe = iio_priv(indio_dev);
 425         int ret;
 426
 427         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
 428                                  AFE440X_CONTROL2_PDN_AFE,
 429                                  AFE440X_CONTROL2_PDN_AFE);
 430         if (ret)
 431                 return ret;
 432
 433         ret = regulator_disable(afe->regulator);
 434         if (ret) {
 435                 dev_err(dev, "Unable to disable regulator\n");
 436                 return ret;
 437         }
 438
 439         return 0;
 440 }
 441
 442 static int __maybe_unused afe4404_resume(struct device *dev)
 443 {
 444         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 445         struct afe4404_data *afe = iio_priv(indio_dev);
 446         int ret;
 447
 448         ret = regulator_enable(afe->regulator);
 449         if (ret) {
 450                 dev_err(dev, "Unable to enable regulator\n");
 451                 return ret;
 452         }
 453
 454         ret = regmap_update_bits(afe->regmap, AFE440X_CONTROL2,
 455                                  AFE440X_CONTROL2_PDN_AFE, 0);
 456         if (ret)
 457                 return ret;
 458
 459         return 0;
 460 }
 461
 462 static SIMPLE_DEV_PM_OPS(afe4404_pm_ops, afe4404_suspend, afe4404_resume);
 463
 464 static int afe4404_probe(struct i2c_client *client,
 465                          const struct i2c_device_id *id)
 466 {
 467         struct iio_dev *indio_dev;
 468         struct afe4404_data *afe;
 469         int i, ret;
 470
 471         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*afe));
 472         if (!indio_dev)
 473                 return -ENOMEM;
 474
 475         afe = iio_priv(indio_dev);
 476         i2c_set_clientdata(client, indio_dev);
 477
 478         afe->dev = &client->dev;
 479         afe->irq = client->irq;
 480
 481         afe->regmap = devm_regmap_init_i2c(client, &afe4404_regmap_config);
 482         if (IS_ERR(afe->regmap)) {
 483                 dev_err(afe->dev, "Unable to allocate register map\n");
 484                 return PTR_ERR(afe->regmap);
 485         }
 486
 487         for (i = 0; i < F_MAX_FIELDS; i++) {
 488                 afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap,
 489                                                          afe4404_reg_fields[i]);
 490                 if (IS_ERR(afe->fields[i])) {
 491                         dev_err(afe->dev, "Unable to allocate regmap fields\n");
 492                         return PTR_ERR(afe->fields[i]);
 493                 }
 494         }
 495
 496         afe->regulator = devm_regulator_get(afe->dev, "tx_sup");
 497         if (IS_ERR(afe->regulator)) {
 498                 dev_err(afe->dev, "Unable to get regulator\n");
 499                 return PTR_ERR(afe->regulator);
 500         }
 501         ret = regulator_enable(afe->regulator);
 502         if (ret) {
 503                 dev_err(afe->dev, "Unable to enable regulator\n");
 504                 return ret;
 505         }
 506
 507         ret = regmap_write(afe->regmap, AFE440X_CONTROL0,
 508                            AFE440X_CONTROL0_SW_RESET);
 509         if (ret) {
 510                 dev_err(afe->dev, "Unable to reset device\n");
 511                 goto disable_reg;
 512         }
 513
 514         ret = regmap_multi_reg_write(afe->regmap, afe4404_reg_sequences,
 515                                      ARRAY_SIZE(afe4404_reg_sequences));
 516         if (ret) {
 517                 dev_err(afe->dev, "Unable to set register defaults\n");
 518                 goto disable_reg;
 519         }
 520
 521         indio_dev->modes = INDIO_DIRECT_MODE;
 522         indio_dev->channels = afe4404_channels;
 523         indio_dev->num_channels = ARRAY_SIZE(afe4404_channels);
 524         indio_dev->name = AFE4404_DRIVER_NAME;
 525         indio_dev->info = &afe4404_iio_info;
 526
 527         if (afe->irq > 0) {
 528                 afe->trig = devm_iio_trigger_alloc(afe->dev,
 529                                                    "%s-dev%d",
 530                                                    indio_dev->name,
 531                                                    indio_dev->id);
 532                 if (!afe->trig) {
 533                         dev_err(afe->dev, "Unable to allocate IIO trigger\n");
 534                         ret = -ENOMEM;
 535                         goto disable_reg;
 536                 }
 537
 538                 iio_trigger_set_drvdata(afe->trig, indio_dev);
 539
 540                 afe->trig->ops = &afe4404_trigger_ops;
 541
 542                 ret = iio_trigger_register(afe->trig);
 543                 if (ret) {
 544                         dev_err(afe->dev, "Unable to register IIO trigger\n");
 545                         goto disable_reg;
 546                 }
 547
 548                 ret = devm_request_threaded_irq(afe->dev, afe->irq,
 549                                                 iio_trigger_generic_data_rdy_poll,
 550                                                 NULL, IRQF_ONESHOT,
 551                                                 AFE4404_DRIVER_NAME,
 552                                                 afe->trig);
 553                 if (ret) {
 554                         dev_err(afe->dev, "Unable to request IRQ\n");
 555                         goto disable_reg;
 556                 }
 557         }
 558
 559         ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
 560                                          afe4404_trigger_handler, NULL);
 561         if (ret) {
 562                 dev_err(afe->dev, "Unable to setup buffer\n");
 563                 goto unregister_trigger;
 564         }
 565
 566         ret = iio_device_register(indio_dev);
 567         if (ret) {
 568                 dev_err(afe->dev, "Unable to register IIO device\n");
 569                 goto unregister_triggered_buffer;
 570         }
 571
 572         return 0;
 573
 574 unregister_triggered_buffer:
 575         iio_triggered_buffer_cleanup(indio_dev);
 576 unregister_trigger:
 577         if (afe->irq > 0)
 578                 iio_trigger_unregister(afe->trig);
 579 disable_reg:
 580         regulator_disable(afe->regulator);
 581
 582         return ret;
 583 }
 584
 585 static int afe4404_remove(struct i2c_client *client)
 586 {
 587         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 588         struct afe4404_data *afe = iio_priv(indio_dev);
 589         int ret;
 590
 591         iio_device_unregister(indio_dev);
 592
 593         iio_triggered_buffer_cleanup(indio_dev);
 594
 595         if (afe->irq > 0)
 596                 iio_trigger_unregister(afe->trig);
 597
 598         ret = regulator_disable(afe->regulator);
 599         if (ret) {
 600                 dev_err(afe->dev, "Unable to disable regulator\n");
 601                 return ret;
 602         }
 603
 604         return 0;
 605 }
 606
 607 static const struct i2c_device_id afe4404_ids[] = {
 608         { "afe4404", 0 },
 609         { /* sentinel */ }
 610 };
 611 MODULE_DEVICE_TABLE(i2c, afe4404_ids);
 612
 613 static struct i2c_driver afe4404_i2c_driver = {
 614         .driver = {
 615                 .name = AFE4404_DRIVER_NAME,
 616                 .of_match_table = afe4404_of_match,
 617                 .pm = &afe4404_pm_ops,
 618         },
 619         .probe = afe4404_probe,
 620         .remove = afe4404_remove,
 621         .id_table = afe4404_ids,
 622 };
 623 module_i2c_driver(afe4404_i2c_driver);
 624
 625 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
 626 MODULE_DESCRIPTION("TI AFE4404 Heart Rate Monitor and Pulse Oximeter AFE");
 627 MODULE_LICENSE("GPL v2");