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 <linux/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], ®_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, ®, 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, field; 249 int ret; 250 251 switch (chan->type) { 252 case IIO_INTENSITY: 253 switch (mask) { 254 case IIO_CHAN_INFO_RAW: 255 reg = afe4403_channel_values[chan->address]; 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 field = afe4403_channel_leds[chan->address]; 266 ret = regmap_field_read(afe->fields[field], val); 267 if (ret) 268 return ret; 269 return IIO_VAL_INT; 270 case IIO_CHAN_INFO_SCALE: 271 *val = 0; 272 *val2 = 800000; 273 return IIO_VAL_INT_PLUS_MICRO; 274 } 275 break; 276 default: 277 break; 278 } 279 280 return -EINVAL; 281 } 282 283 static int afe4403_write_raw(struct iio_dev *indio_dev, 284 struct iio_chan_spec const *chan, 285 int val, int val2, long mask) 286 { 287 struct afe4403_data *afe = iio_priv(indio_dev); 288 unsigned int field = afe4403_channel_leds[chan->address]; 289 290 switch (chan->type) { 291 case IIO_CURRENT: 292 switch (mask) { 293 case IIO_CHAN_INFO_RAW: 294 return regmap_field_write(afe->fields[field], val); 295 } 296 break; 297 default: 298 break; 299 } 300 301 return -EINVAL; 302 } 303 304 static const struct iio_info afe4403_iio_info = { 305 .attrs = &afe440x_attribute_group, 306 .read_raw = afe4403_read_raw, 307 .write_raw = afe4403_write_raw, 308 }; 309 310 static irqreturn_t afe4403_trigger_handler(int irq, void *private) 311 { 312 struct iio_poll_func *pf = private; 313 struct iio_dev *indio_dev = pf->indio_dev; 314 struct afe4403_data *afe = iio_priv(indio_dev); 315 int ret, bit, i = 0; 316 u8 tx[4] = {AFE440X_CONTROL0, 0x0, 0x0, AFE440X_CONTROL0_READ}; 317 u8 rx[3]; 318 319 /* Enable reading from the device */ 320 ret = spi_write_then_read(afe->spi, tx, 4, NULL, 0); 321 if (ret) 322 goto err; 323 324 iio_for_each_active_channel(indio_dev, bit) { 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 static void afe4403_regulator_disable(void *data) 349 { 350 struct regulator *regulator = data; 351 352 regulator_disable(regulator); 353 } 354 355 #define AFE4403_TIMING_PAIRS \ 356 { AFE440X_LED2STC, 0x000050 }, \ 357 { AFE440X_LED2ENDC, 0x0003e7 }, \ 358 { AFE440X_LED1LEDSTC, 0x0007d0 }, \ 359 { AFE440X_LED1LEDENDC, 0x000bb7 }, \ 360 { AFE440X_ALED2STC, 0x000438 }, \ 361 { AFE440X_ALED2ENDC, 0x0007cf }, \ 362 { AFE440X_LED1STC, 0x000820 }, \ 363 { AFE440X_LED1ENDC, 0x000bb7 }, \ 364 { AFE440X_LED2LEDSTC, 0x000000 }, \ 365 { AFE440X_LED2LEDENDC, 0x0003e7 }, \ 366 { AFE440X_ALED1STC, 0x000c08 }, \ 367 { AFE440X_ALED1ENDC, 0x000f9f }, \ 368 { AFE440X_LED2CONVST, 0x0003ef }, \ 369 { AFE440X_LED2CONVEND, 0x0007cf }, \ 370 { AFE440X_ALED2CONVST, 0x0007d7 }, \ 371 { AFE440X_ALED2CONVEND, 0x000bb7 }, \ 372 { AFE440X_LED1CONVST, 0x000bbf }, \ 373 { AFE440X_LED1CONVEND, 0x009c3f }, \ 374 { AFE440X_ALED1CONVST, 0x000fa7 }, \ 375 { AFE440X_ALED1CONVEND, 0x001387 }, \ 376 { AFE440X_ADCRSTSTCT0, 0x0003e8 }, \ 377 { AFE440X_ADCRSTENDCT0, 0x0003eb }, \ 378 { AFE440X_ADCRSTSTCT1, 0x0007d0 }, \ 379 { AFE440X_ADCRSTENDCT1, 0x0007d3 }, \ 380 { AFE440X_ADCRSTSTCT2, 0x000bb8 }, \ 381 { AFE440X_ADCRSTENDCT2, 0x000bbb }, \ 382 { AFE440X_ADCRSTSTCT3, 0x000fa0 }, \ 383 { AFE440X_ADCRSTENDCT3, 0x000fa3 }, \ 384 { AFE440X_PRPCOUNT, 0x009c3f }, \ 385 { AFE440X_PDNCYCLESTC, 0x001518 }, \ 386 { AFE440X_PDNCYCLEENDC, 0x00991f } 387 388 static const struct reg_sequence afe4403_reg_sequences[] = { 389 AFE4403_TIMING_PAIRS, 390 { AFE440X_CONTROL1, AFE440X_CONTROL1_TIMEREN }, 391 { AFE4403_TIAGAIN, AFE440X_TIAGAIN_ENSEPGAIN }, 392 }; 393 394 static const struct regmap_range afe4403_yes_ranges[] = { 395 regmap_reg_range(AFE440X_LED2VAL, AFE440X_LED1_ALED1VAL), 396 }; 397 398 static const struct regmap_access_table afe4403_volatile_table = { 399 .yes_ranges = afe4403_yes_ranges, 400 .n_yes_ranges = ARRAY_SIZE(afe4403_yes_ranges), 401 }; 402 403 static const struct regmap_config afe4403_regmap_config = { 404 .reg_bits = 8, 405 .val_bits = 24, 406 407 .max_register = AFE440X_PDNCYCLEENDC, 408 .cache_type = REGCACHE_RBTREE, 409 .volatile_table = &afe4403_volatile_table, 410 }; 411 412 static const struct of_device_id afe4403_of_match[] = { 413 { .compatible = "ti,afe4403", }, 414 { /* sentinel */ } 415 }; 416 MODULE_DEVICE_TABLE(of, afe4403_of_match); 417 418 static int afe4403_suspend(struct device *dev) 419 { 420 struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev)); 421 struct afe4403_data *afe = iio_priv(indio_dev); 422 int ret; 423 424 ret = regmap_set_bits(afe->regmap, AFE440X_CONTROL2, 425 AFE440X_CONTROL2_PDN_AFE); 426 if (ret) 427 return ret; 428 429 ret = regulator_disable(afe->regulator); 430 if (ret) { 431 dev_err(dev, "Unable to disable regulator\n"); 432 return ret; 433 } 434 435 return 0; 436 } 437 438 static int afe4403_resume(struct device *dev) 439 { 440 struct iio_dev *indio_dev = spi_get_drvdata(to_spi_device(dev)); 441 struct afe4403_data *afe = iio_priv(indio_dev); 442 int ret; 443 444 ret = regulator_enable(afe->regulator); 445 if (ret) { 446 dev_err(dev, "Unable to enable regulator\n"); 447 return ret; 448 } 449 450 ret = regmap_clear_bits(afe->regmap, AFE440X_CONTROL2, 451 AFE440X_CONTROL2_PDN_AFE); 452 if (ret) 453 return ret; 454 455 return 0; 456 } 457 458 static DEFINE_SIMPLE_DEV_PM_OPS(afe4403_pm_ops, afe4403_suspend, 459 afe4403_resume); 460 461 static int afe4403_probe(struct spi_device *spi) 462 { 463 struct iio_dev *indio_dev; 464 struct afe4403_data *afe; 465 int i, ret; 466 467 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*afe)); 468 if (!indio_dev) 469 return -ENOMEM; 470 471 afe = iio_priv(indio_dev); 472 spi_set_drvdata(spi, indio_dev); 473 474 afe->dev = &spi->dev; 475 afe->spi = spi; 476 afe->irq = spi->irq; 477 478 afe->regmap = devm_regmap_init_spi(spi, &afe4403_regmap_config); 479 if (IS_ERR(afe->regmap)) { 480 dev_err(afe->dev, "Unable to allocate register map\n"); 481 return PTR_ERR(afe->regmap); 482 } 483 484 for (i = 0; i < F_MAX_FIELDS; i++) { 485 afe->fields[i] = devm_regmap_field_alloc(afe->dev, afe->regmap, 486 afe4403_reg_fields[i]); 487 if (IS_ERR(afe->fields[i])) { 488 dev_err(afe->dev, "Unable to allocate regmap fields\n"); 489 return PTR_ERR(afe->fields[i]); 490 } 491 } 492 493 afe->regulator = devm_regulator_get(afe->dev, "tx_sup"); 494 if (IS_ERR(afe->regulator)) 495 return dev_err_probe(afe->dev, PTR_ERR(afe->regulator), 496 "Unable to get regulator\n"); 497 498 ret = regulator_enable(afe->regulator); 499 if (ret) { 500 dev_err(afe->dev, "Unable to enable regulator\n"); 501 return ret; 502 } 503 ret = devm_add_action_or_reset(afe->dev, afe4403_regulator_disable, afe->regulator); 504 if (ret) { 505 dev_err(afe->dev, "Unable to add regulator disable action\n"); 506 return ret; 507 } 508 509 ret = regmap_write(afe->regmap, AFE440X_CONTROL0, 510 AFE440X_CONTROL0_SW_RESET); 511 if (ret) { 512 dev_err(afe->dev, "Unable to reset device\n"); 513 return ret; 514 } 515 516 ret = regmap_multi_reg_write(afe->regmap, afe4403_reg_sequences, 517 ARRAY_SIZE(afe4403_reg_sequences)); 518 if (ret) { 519 dev_err(afe->dev, "Unable to set register defaults\n"); 520 return ret; 521 } 522 523 indio_dev->modes = INDIO_DIRECT_MODE; 524 indio_dev->channels = afe4403_channels; 525 indio_dev->num_channels = ARRAY_SIZE(afe4403_channels); 526 indio_dev->name = AFE4403_DRIVER_NAME; 527 indio_dev->info = &afe4403_iio_info; 528 529 if (afe->irq > 0) { 530 afe->trig = devm_iio_trigger_alloc(afe->dev, 531 "%s-dev%d", 532 indio_dev->name, 533 iio_device_id(indio_dev)); 534 if (!afe->trig) { 535 dev_err(afe->dev, "Unable to allocate IIO trigger\n"); 536 return -ENOMEM; 537 } 538 539 iio_trigger_set_drvdata(afe->trig, indio_dev); 540 541 ret = devm_iio_trigger_register(afe->dev, afe->trig); 542 if (ret) { 543 dev_err(afe->dev, "Unable to register IIO trigger\n"); 544 return ret; 545 } 546 547 ret = devm_request_threaded_irq(afe->dev, afe->irq, 548 iio_trigger_generic_data_rdy_poll, 549 NULL, IRQF_ONESHOT, 550 AFE4403_DRIVER_NAME, 551 afe->trig); 552 if (ret) { 553 dev_err(afe->dev, "Unable to request IRQ\n"); 554 return ret; 555 } 556 } 557 558 ret = devm_iio_triggered_buffer_setup(afe->dev, indio_dev, 559 &iio_pollfunc_store_time, 560 afe4403_trigger_handler, NULL); 561 if (ret) { 562 dev_err(afe->dev, "Unable to setup buffer\n"); 563 return ret; 564 } 565 566 ret = devm_iio_device_register(afe->dev, indio_dev); 567 if (ret) { 568 dev_err(afe->dev, "Unable to register IIO device\n"); 569 return ret; 570 } 571 572 return 0; 573 } 574 575 static const struct spi_device_id afe4403_ids[] = { 576 { "afe4403", 0 }, 577 { /* sentinel */ } 578 }; 579 MODULE_DEVICE_TABLE(spi, afe4403_ids); 580 581 static struct spi_driver afe4403_spi_driver = { 582 .driver = { 583 .name = AFE4403_DRIVER_NAME, 584 .of_match_table = afe4403_of_match, 585 .pm = pm_sleep_ptr(&afe4403_pm_ops), 586 }, 587 .probe = afe4403_probe, 588 .id_table = afe4403_ids, 589 }; 590 module_spi_driver(afe4403_spi_driver); 591 592 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>"); 593 MODULE_DESCRIPTION("TI AFE4403 Heart Rate Monitor and Pulse Oximeter AFE"); 594 MODULE_LICENSE("GPL v2"); 595