1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * MAX11410 SPI ADC driver 4 * 5 * Copyright 2022 Analog Devices Inc. 6 */ 7 #include <linux/bitfield.h> 8 #include <linux/delay.h> 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/regulator/consumer.h> 16 #include <linux/spi/spi.h> 17 18 #include <linux/unaligned.h> 19 20 #include <linux/iio/buffer.h> 21 #include <linux/iio/sysfs.h> 22 #include <linux/iio/trigger.h> 23 #include <linux/iio/trigger_consumer.h> 24 #include <linux/iio/triggered_buffer.h> 25 26 #define MAX11410_REG_CONV_START 0x01 27 #define MAX11410_CONV_TYPE_SINGLE 0x00 28 #define MAX11410_CONV_TYPE_CONTINUOUS 0x01 29 #define MAX11410_REG_CAL_START 0x03 30 #define MAX11410_CAL_START_SELF 0x00 31 #define MAX11410_CAL_START_PGA 0x01 32 #define MAX11410_REG_GPIO_CTRL(ch) ((ch) ? 0x05 : 0x04) 33 #define MAX11410_GPIO_INTRB 0xC1 34 #define MAX11410_REG_FILTER 0x08 35 #define MAX11410_FILTER_RATE_MASK GENMASK(3, 0) 36 #define MAX11410_FILTER_RATE_MAX 0x0F 37 #define MAX11410_FILTER_LINEF_MASK GENMASK(5, 4) 38 #define MAX11410_FILTER_50HZ BIT(5) 39 #define MAX11410_FILTER_60HZ BIT(4) 40 #define MAX11410_REG_CTRL 0x09 41 #define MAX11410_CTRL_REFSEL_MASK GENMASK(2, 0) 42 #define MAX11410_CTRL_VREFN_BUF_BIT BIT(3) 43 #define MAX11410_CTRL_VREFP_BUF_BIT BIT(4) 44 #define MAX11410_CTRL_FORMAT_BIT BIT(5) 45 #define MAX11410_CTRL_UNIPOLAR_BIT BIT(6) 46 #define MAX11410_REG_MUX_CTRL0 0x0B 47 #define MAX11410_REG_PGA 0x0E 48 #define MAX11410_PGA_GAIN_MASK GENMASK(2, 0) 49 #define MAX11410_PGA_SIG_PATH_MASK GENMASK(5, 4) 50 #define MAX11410_PGA_SIG_PATH_BUFFERED 0x00 51 #define MAX11410_PGA_SIG_PATH_BYPASS 0x01 52 #define MAX11410_PGA_SIG_PATH_PGA 0x02 53 #define MAX11410_REG_DATA0 0x30 54 #define MAX11410_REG_STATUS 0x38 55 #define MAX11410_STATUS_CONV_READY_BIT BIT(0) 56 #define MAX11410_STATUS_CAL_READY_BIT BIT(2) 57 58 #define MAX11410_REFSEL_AVDD_AGND 0x03 59 #define MAX11410_REFSEL_MAX 0x06 60 #define MAX11410_SIG_PATH_MAX 0x02 61 #define MAX11410_CHANNEL_INDEX_MAX 0x0A 62 #define MAX11410_AINP_AVDD 0x0A 63 #define MAX11410_AINN_GND 0x0A 64 65 #define MAX11410_CONVERSION_TIMEOUT_MS 2000 66 #define MAX11410_CALIB_TIMEOUT_MS 2000 67 68 #define MAX11410_SCALE_AVAIL_SIZE 8 69 70 enum max11410_filter { 71 MAX11410_FILTER_FIR5060, 72 MAX11410_FILTER_FIR50, 73 MAX11410_FILTER_FIR60, 74 MAX11410_FILTER_SINC4, 75 }; 76 77 static const u8 max11410_sampling_len[] = { 78 [MAX11410_FILTER_FIR5060] = 5, 79 [MAX11410_FILTER_FIR50] = 6, 80 [MAX11410_FILTER_FIR60] = 6, 81 [MAX11410_FILTER_SINC4] = 10, 82 }; 83 84 static const int max11410_sampling_rates[4][10][2] = { 85 [MAX11410_FILTER_FIR5060] = { 86 { 1, 100000 }, 87 { 2, 100000 }, 88 { 4, 200000 }, 89 { 8, 400000 }, 90 { 16, 800000 } 91 }, 92 [MAX11410_FILTER_FIR50] = { 93 { 1, 300000 }, 94 { 2, 700000 }, 95 { 5, 300000 }, 96 { 10, 700000 }, 97 { 21, 300000 }, 98 { 40 } 99 }, 100 [MAX11410_FILTER_FIR60] = { 101 { 1, 300000 }, 102 { 2, 700000 }, 103 { 5, 300000 }, 104 { 10, 700000 }, 105 { 21, 300000 }, 106 { 40 } 107 }, 108 [MAX11410_FILTER_SINC4] = { 109 { 4 }, 110 { 10 }, 111 { 20 }, 112 { 40 }, 113 { 60 }, 114 { 120 }, 115 { 240 }, 116 { 480 }, 117 { 960 }, 118 { 1920 } 119 } 120 }; 121 122 struct max11410_channel_config { 123 u32 settling_time_us; 124 u32 *scale_avail; 125 u8 refsel; 126 u8 sig_path; 127 u8 gain; 128 bool bipolar; 129 bool buffered_vrefp; 130 bool buffered_vrefn; 131 }; 132 133 struct max11410_state { 134 struct spi_device *spi_dev; 135 struct iio_trigger *trig; 136 struct completion completion; 137 struct mutex lock; /* Prevent changing channel config during sampling */ 138 struct regmap *regmap; 139 struct regulator *avdd; 140 struct regulator *vrefp[3]; 141 struct regulator *vrefn[3]; 142 struct max11410_channel_config *channels; 143 int irq; 144 struct { 145 u32 data __aligned(IIO_DMA_MINALIGN); 146 s64 ts __aligned(8); 147 } scan; 148 }; 149 150 static const struct iio_chan_spec chanspec_template = { 151 .type = IIO_VOLTAGE, 152 .indexed = 1, 153 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 154 BIT(IIO_CHAN_INFO_SCALE) | 155 BIT(IIO_CHAN_INFO_OFFSET), 156 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), 157 .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_SAMP_FREQ), 158 .scan_type = { 159 .sign = 's', 160 .realbits = 24, 161 .storagebits = 32, 162 .endianness = IIO_LE, 163 }, 164 }; 165 166 static unsigned int max11410_reg_size(unsigned int reg) 167 { 168 /* Registers from 0x00 to 0x10 are 1 byte, the rest are 3 bytes long. */ 169 return reg <= 0x10 ? 1 : 3; 170 } 171 172 static int max11410_write_reg(struct max11410_state *st, unsigned int reg, 173 unsigned int val) 174 { 175 /* This driver only needs to write 8-bit registers */ 176 if (max11410_reg_size(reg) != 1) 177 return -EINVAL; 178 179 return regmap_write(st->regmap, reg, val); 180 } 181 182 static int max11410_read_reg(struct max11410_state *st, unsigned int reg, 183 int *val) 184 { 185 int ret; 186 187 if (max11410_reg_size(reg) == 3) { 188 ret = regmap_bulk_read(st->regmap, reg, &st->scan.data, 3); 189 if (ret) 190 return ret; 191 192 *val = get_unaligned_be24(&st->scan.data); 193 return 0; 194 } 195 196 return regmap_read(st->regmap, reg, val); 197 } 198 199 static struct regulator *max11410_get_vrefp(struct max11410_state *st, 200 u8 refsel) 201 { 202 refsel = refsel % 4; 203 if (refsel == 3) 204 return st->avdd; 205 206 return st->vrefp[refsel]; 207 } 208 209 static struct regulator *max11410_get_vrefn(struct max11410_state *st, 210 u8 refsel) 211 { 212 if (refsel > 2) 213 return NULL; 214 215 return st->vrefn[refsel]; 216 } 217 218 static const struct regmap_config regmap_config = { 219 .reg_bits = 8, 220 .val_bits = 8, 221 .max_register = 0x39, 222 }; 223 224 static ssize_t max11410_notch_en_show(struct device *dev, 225 struct device_attribute *devattr, 226 char *buf) 227 { 228 struct iio_dev *indio_dev = dev_get_drvdata(dev); 229 struct max11410_state *state = iio_priv(indio_dev); 230 struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr); 231 unsigned int val; 232 int ret; 233 234 ret = max11410_read_reg(state, MAX11410_REG_FILTER, &val); 235 if (ret) 236 return ret; 237 238 switch (iio_attr->address) { 239 case 0: 240 val = !FIELD_GET(MAX11410_FILTER_50HZ, val); 241 break; 242 case 1: 243 val = !FIELD_GET(MAX11410_FILTER_60HZ, val); 244 break; 245 case 2: 246 val = FIELD_GET(MAX11410_FILTER_LINEF_MASK, val) == 3; 247 break; 248 default: 249 return -EINVAL; 250 } 251 252 return sysfs_emit(buf, "%d\n", val); 253 } 254 255 static ssize_t max11410_notch_en_store(struct device *dev, 256 struct device_attribute *devattr, 257 const char *buf, size_t count) 258 { 259 struct iio_dev_attr *iio_attr = to_iio_dev_attr(devattr); 260 struct iio_dev *indio_dev = dev_get_drvdata(dev); 261 struct max11410_state *state = iio_priv(indio_dev); 262 unsigned int filter_bits; 263 bool enable; 264 int ret; 265 266 ret = kstrtobool(buf, &enable); 267 if (ret) 268 return ret; 269 270 switch (iio_attr->address) { 271 case 0: 272 filter_bits = MAX11410_FILTER_50HZ; 273 break; 274 case 1: 275 filter_bits = MAX11410_FILTER_60HZ; 276 break; 277 case 2: 278 default: 279 filter_bits = MAX11410_FILTER_50HZ | MAX11410_FILTER_60HZ; 280 enable = !enable; 281 break; 282 } 283 284 if (enable) 285 ret = regmap_clear_bits(state->regmap, MAX11410_REG_FILTER, 286 filter_bits); 287 else 288 ret = regmap_set_bits(state->regmap, MAX11410_REG_FILTER, 289 filter_bits); 290 291 if (ret) 292 return ret; 293 294 return count; 295 } 296 297 static ssize_t in_voltage_filter2_notch_center_show(struct device *dev, 298 struct device_attribute *devattr, 299 char *buf) 300 { 301 struct iio_dev *indio_dev = dev_get_drvdata(dev); 302 struct max11410_state *state = iio_priv(indio_dev); 303 int ret, reg, rate, filter; 304 305 ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®); 306 if (ret) 307 return ret; 308 309 rate = FIELD_GET(MAX11410_FILTER_RATE_MASK, reg); 310 rate = clamp_val(rate, 0, 311 max11410_sampling_len[MAX11410_FILTER_SINC4] - 1); 312 filter = max11410_sampling_rates[MAX11410_FILTER_SINC4][rate][0]; 313 314 return sysfs_emit(buf, "%d\n", filter); 315 } 316 317 static IIO_CONST_ATTR(in_voltage_filter0_notch_center, "50"); 318 static IIO_CONST_ATTR(in_voltage_filter1_notch_center, "60"); 319 static IIO_DEVICE_ATTR_RO(in_voltage_filter2_notch_center, 2); 320 321 static IIO_DEVICE_ATTR(in_voltage_filter0_notch_en, 0644, 322 max11410_notch_en_show, max11410_notch_en_store, 0); 323 static IIO_DEVICE_ATTR(in_voltage_filter1_notch_en, 0644, 324 max11410_notch_en_show, max11410_notch_en_store, 1); 325 static IIO_DEVICE_ATTR(in_voltage_filter2_notch_en, 0644, 326 max11410_notch_en_show, max11410_notch_en_store, 2); 327 328 static struct attribute *max11410_attributes[] = { 329 &iio_const_attr_in_voltage_filter0_notch_center.dev_attr.attr, 330 &iio_const_attr_in_voltage_filter1_notch_center.dev_attr.attr, 331 &iio_dev_attr_in_voltage_filter2_notch_center.dev_attr.attr, 332 &iio_dev_attr_in_voltage_filter0_notch_en.dev_attr.attr, 333 &iio_dev_attr_in_voltage_filter1_notch_en.dev_attr.attr, 334 &iio_dev_attr_in_voltage_filter2_notch_en.dev_attr.attr, 335 NULL 336 }; 337 338 static const struct attribute_group max11410_attribute_group = { 339 .attrs = max11410_attributes, 340 }; 341 342 static int max11410_set_input_mux(struct max11410_state *st, u8 ainp, u8 ainn) 343 { 344 if (ainp > MAX11410_CHANNEL_INDEX_MAX || 345 ainn > MAX11410_CHANNEL_INDEX_MAX) 346 return -EINVAL; 347 348 return max11410_write_reg(st, MAX11410_REG_MUX_CTRL0, 349 (ainp << 4) | ainn); 350 } 351 352 static int max11410_configure_channel(struct max11410_state *st, 353 struct iio_chan_spec const *chan) 354 { 355 struct max11410_channel_config cfg = st->channels[chan->address]; 356 unsigned int regval; 357 int ret; 358 359 if (chan->differential) 360 ret = max11410_set_input_mux(st, chan->channel, chan->channel2); 361 else 362 ret = max11410_set_input_mux(st, chan->channel, 363 MAX11410_AINN_GND); 364 365 if (ret) 366 return ret; 367 368 regval = FIELD_PREP(MAX11410_CTRL_VREFP_BUF_BIT, cfg.buffered_vrefp) | 369 FIELD_PREP(MAX11410_CTRL_VREFN_BUF_BIT, cfg.buffered_vrefn) | 370 FIELD_PREP(MAX11410_CTRL_REFSEL_MASK, cfg.refsel) | 371 FIELD_PREP(MAX11410_CTRL_UNIPOLAR_BIT, cfg.bipolar ? 0 : 1); 372 ret = regmap_update_bits(st->regmap, MAX11410_REG_CTRL, 373 MAX11410_CTRL_REFSEL_MASK | 374 MAX11410_CTRL_VREFP_BUF_BIT | 375 MAX11410_CTRL_VREFN_BUF_BIT | 376 MAX11410_CTRL_UNIPOLAR_BIT, regval); 377 if (ret) 378 return ret; 379 380 regval = FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, cfg.sig_path) | 381 FIELD_PREP(MAX11410_PGA_GAIN_MASK, cfg.gain); 382 ret = regmap_write(st->regmap, MAX11410_REG_PGA, regval); 383 if (ret) 384 return ret; 385 386 if (cfg.settling_time_us) 387 fsleep(cfg.settling_time_us); 388 389 return 0; 390 } 391 392 static int max11410_sample(struct max11410_state *st, int *sample_raw, 393 struct iio_chan_spec const *chan) 394 { 395 int val, ret; 396 397 ret = max11410_configure_channel(st, chan); 398 if (ret) 399 return ret; 400 401 if (st->irq > 0) 402 reinit_completion(&st->completion); 403 404 /* Start Conversion */ 405 ret = max11410_write_reg(st, MAX11410_REG_CONV_START, 406 MAX11410_CONV_TYPE_SINGLE); 407 if (ret) 408 return ret; 409 410 if (st->irq > 0) { 411 /* Wait for an interrupt. */ 412 ret = wait_for_completion_timeout(&st->completion, 413 msecs_to_jiffies(MAX11410_CONVERSION_TIMEOUT_MS)); 414 if (!ret) 415 return -ETIMEDOUT; 416 } else { 417 int ret2; 418 419 /* Wait for status register Conversion Ready flag */ 420 ret = read_poll_timeout(max11410_read_reg, ret2, 421 ret2 || (val & MAX11410_STATUS_CONV_READY_BIT), 422 5000, MAX11410_CONVERSION_TIMEOUT_MS * 1000, 423 true, st, MAX11410_REG_STATUS, &val); 424 if (ret) 425 return ret; 426 if (ret2) 427 return ret2; 428 } 429 430 /* Read ADC Data */ 431 return max11410_read_reg(st, MAX11410_REG_DATA0, sample_raw); 432 } 433 434 static int max11410_get_scale(struct max11410_state *state, 435 struct max11410_channel_config cfg) 436 { 437 struct regulator *vrefp, *vrefn; 438 int scale; 439 440 vrefp = max11410_get_vrefp(state, cfg.refsel); 441 442 scale = regulator_get_voltage(vrefp) / 1000; 443 vrefn = max11410_get_vrefn(state, cfg.refsel); 444 if (vrefn) 445 scale -= regulator_get_voltage(vrefn) / 1000; 446 447 if (cfg.bipolar) 448 scale *= 2; 449 450 return scale >> cfg.gain; 451 } 452 453 static int max11410_read_raw(struct iio_dev *indio_dev, 454 struct iio_chan_spec const *chan, 455 int *val, int *val2, long info) 456 { 457 struct max11410_state *state = iio_priv(indio_dev); 458 struct max11410_channel_config cfg = state->channels[chan->address]; 459 int ret, reg_val, filter, rate; 460 461 switch (info) { 462 case IIO_CHAN_INFO_SCALE: 463 *val = max11410_get_scale(state, cfg); 464 *val2 = chan->scan_type.realbits; 465 return IIO_VAL_FRACTIONAL_LOG2; 466 case IIO_CHAN_INFO_OFFSET: 467 if (cfg.bipolar) 468 *val = -BIT(chan->scan_type.realbits - 1); 469 else 470 *val = 0; 471 472 return IIO_VAL_INT; 473 case IIO_CHAN_INFO_RAW: 474 ret = iio_device_claim_direct_mode(indio_dev); 475 if (ret) 476 return ret; 477 478 mutex_lock(&state->lock); 479 480 ret = max11410_sample(state, ®_val, chan); 481 482 mutex_unlock(&state->lock); 483 484 iio_device_release_direct_mode(indio_dev); 485 486 if (ret) 487 return ret; 488 489 *val = reg_val; 490 491 return IIO_VAL_INT; 492 case IIO_CHAN_INFO_SAMP_FREQ: 493 ret = regmap_read(state->regmap, MAX11410_REG_FILTER, ®_val); 494 if (ret) 495 return ret; 496 497 filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); 498 rate = reg_val & MAX11410_FILTER_RATE_MASK; 499 if (rate >= max11410_sampling_len[filter]) 500 rate = max11410_sampling_len[filter] - 1; 501 502 *val = max11410_sampling_rates[filter][rate][0]; 503 *val2 = max11410_sampling_rates[filter][rate][1]; 504 505 return IIO_VAL_INT_PLUS_MICRO; 506 } 507 return -EINVAL; 508 } 509 510 static int max11410_write_raw(struct iio_dev *indio_dev, 511 struct iio_chan_spec const *chan, 512 int val, int val2, long mask) 513 { 514 struct max11410_state *st = iio_priv(indio_dev); 515 int i, ret, reg_val, filter, gain; 516 u32 *scale_avail; 517 518 switch (mask) { 519 case IIO_CHAN_INFO_SCALE: 520 scale_avail = st->channels[chan->address].scale_avail; 521 if (!scale_avail) 522 return -EOPNOTSUPP; 523 524 /* Accept values in range 0.000001 <= scale < 1.000000 */ 525 if (val != 0 || val2 == 0) 526 return -EINVAL; 527 528 ret = iio_device_claim_direct_mode(indio_dev); 529 if (ret) 530 return ret; 531 532 /* Convert from INT_PLUS_MICRO to FRACTIONAL_LOG2 */ 533 val2 = val2 * DIV_ROUND_CLOSEST(BIT(24), 1000000); 534 val2 = DIV_ROUND_CLOSEST(scale_avail[0], val2); 535 gain = order_base_2(val2); 536 537 st->channels[chan->address].gain = clamp_val(gain, 0, 7); 538 539 iio_device_release_direct_mode(indio_dev); 540 541 return 0; 542 case IIO_CHAN_INFO_SAMP_FREQ: 543 ret = iio_device_claim_direct_mode(indio_dev); 544 if (ret) 545 return ret; 546 547 mutex_lock(&st->lock); 548 549 ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val); 550 if (ret) 551 goto out; 552 553 filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); 554 555 for (i = 0; i < max11410_sampling_len[filter]; ++i) { 556 if (val == max11410_sampling_rates[filter][i][0] && 557 val2 == max11410_sampling_rates[filter][i][1]) 558 break; 559 } 560 if (i == max11410_sampling_len[filter]) { 561 ret = -EINVAL; 562 goto out; 563 } 564 565 ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, 566 MAX11410_FILTER_RATE_MASK, i); 567 568 out: 569 mutex_unlock(&st->lock); 570 iio_device_release_direct_mode(indio_dev); 571 572 return ret; 573 default: 574 return -EINVAL; 575 } 576 } 577 578 static int max11410_read_avail(struct iio_dev *indio_dev, 579 struct iio_chan_spec const *chan, 580 const int **vals, int *type, int *length, 581 long info) 582 { 583 struct max11410_state *st = iio_priv(indio_dev); 584 struct max11410_channel_config cfg; 585 int ret, reg_val, filter; 586 587 switch (info) { 588 case IIO_CHAN_INFO_SAMP_FREQ: 589 ret = regmap_read(st->regmap, MAX11410_REG_FILTER, ®_val); 590 if (ret) 591 return ret; 592 593 filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val); 594 595 *vals = (const int *)max11410_sampling_rates[filter]; 596 *length = max11410_sampling_len[filter] * 2; 597 *type = IIO_VAL_INT_PLUS_MICRO; 598 599 return IIO_AVAIL_LIST; 600 case IIO_CHAN_INFO_SCALE: 601 cfg = st->channels[chan->address]; 602 603 if (!cfg.scale_avail) 604 return -EINVAL; 605 606 *vals = cfg.scale_avail; 607 *length = MAX11410_SCALE_AVAIL_SIZE * 2; 608 *type = IIO_VAL_FRACTIONAL_LOG2; 609 610 return IIO_AVAIL_LIST; 611 } 612 return -EINVAL; 613 } 614 615 static const struct iio_info max11410_info = { 616 .read_raw = max11410_read_raw, 617 .write_raw = max11410_write_raw, 618 .read_avail = max11410_read_avail, 619 .attrs = &max11410_attribute_group, 620 }; 621 622 static irqreturn_t max11410_trigger_handler(int irq, void *p) 623 { 624 struct iio_poll_func *pf = p; 625 struct iio_dev *indio_dev = pf->indio_dev; 626 struct max11410_state *st = iio_priv(indio_dev); 627 int ret; 628 629 ret = max11410_read_reg(st, MAX11410_REG_DATA0, &st->scan.data); 630 if (ret) { 631 dev_err(&indio_dev->dev, "cannot read data\n"); 632 goto out; 633 } 634 635 iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, 636 iio_get_time_ns(indio_dev)); 637 638 out: 639 iio_trigger_notify_done(indio_dev->trig); 640 641 return IRQ_HANDLED; 642 } 643 644 static int max11410_buffer_postenable(struct iio_dev *indio_dev) 645 { 646 struct max11410_state *st = iio_priv(indio_dev); 647 int scan_ch, ret; 648 649 scan_ch = ffs(*indio_dev->active_scan_mask) - 1; 650 651 ret = max11410_configure_channel(st, &indio_dev->channels[scan_ch]); 652 if (ret) 653 return ret; 654 655 /* Start continuous conversion. */ 656 return max11410_write_reg(st, MAX11410_REG_CONV_START, 657 MAX11410_CONV_TYPE_CONTINUOUS); 658 } 659 660 static int max11410_buffer_predisable(struct iio_dev *indio_dev) 661 { 662 struct max11410_state *st = iio_priv(indio_dev); 663 664 /* Stop continuous conversion. */ 665 return max11410_write_reg(st, MAX11410_REG_CONV_START, 666 MAX11410_CONV_TYPE_SINGLE); 667 } 668 669 static const struct iio_buffer_setup_ops max11410_buffer_ops = { 670 .postenable = &max11410_buffer_postenable, 671 .predisable = &max11410_buffer_predisable, 672 .validate_scan_mask = &iio_validate_scan_mask_onehot, 673 }; 674 675 static const struct iio_trigger_ops max11410_trigger_ops = { 676 .validate_device = iio_trigger_validate_own_device, 677 }; 678 679 static irqreturn_t max11410_interrupt(int irq, void *dev_id) 680 { 681 struct iio_dev *indio_dev = dev_id; 682 struct max11410_state *st = iio_priv(indio_dev); 683 684 if (iio_buffer_enabled(indio_dev)) 685 iio_trigger_poll_nested(st->trig); 686 else 687 complete(&st->completion); 688 689 return IRQ_HANDLED; 690 }; 691 692 static int max11410_parse_channels(struct max11410_state *st, 693 struct iio_dev *indio_dev) 694 { 695 struct iio_chan_spec chanspec = chanspec_template; 696 struct device *dev = &st->spi_dev->dev; 697 struct max11410_channel_config *cfg; 698 struct iio_chan_spec *channels; 699 u32 reference, sig_path; 700 const char *node_name; 701 u32 inputs[2], scale; 702 unsigned int num_ch; 703 int chan_idx = 0; 704 int ret, i; 705 706 num_ch = device_get_child_node_count(dev); 707 if (num_ch == 0) 708 return dev_err_probe(&indio_dev->dev, -ENODEV, 709 "FW has no channels defined\n"); 710 711 /* Reserve space for soft timestamp channel */ 712 num_ch++; 713 channels = devm_kcalloc(dev, num_ch, sizeof(*channels), GFP_KERNEL); 714 if (!channels) 715 return -ENOMEM; 716 717 st->channels = devm_kcalloc(dev, num_ch, sizeof(*st->channels), 718 GFP_KERNEL); 719 if (!st->channels) 720 return -ENOMEM; 721 722 device_for_each_child_node_scoped(dev, child) { 723 node_name = fwnode_get_name(child); 724 if (fwnode_property_present(child, "diff-channels")) { 725 ret = fwnode_property_read_u32_array(child, 726 "diff-channels", 727 inputs, 728 ARRAY_SIZE(inputs)); 729 730 chanspec.differential = 1; 731 } else { 732 ret = fwnode_property_read_u32(child, "reg", &inputs[0]); 733 734 inputs[1] = 0; 735 chanspec.differential = 0; 736 } 737 if (ret) 738 return ret; 739 740 if (inputs[0] > MAX11410_CHANNEL_INDEX_MAX || 741 inputs[1] > MAX11410_CHANNEL_INDEX_MAX) 742 return dev_err_probe(&indio_dev->dev, -EINVAL, 743 "Invalid channel index for %s, should be less than %d\n", 744 node_name, 745 MAX11410_CHANNEL_INDEX_MAX + 1); 746 747 cfg = &st->channels[chan_idx]; 748 749 reference = MAX11410_REFSEL_AVDD_AGND; 750 fwnode_property_read_u32(child, "adi,reference", &reference); 751 if (reference > MAX11410_REFSEL_MAX) 752 return dev_err_probe(&indio_dev->dev, -EINVAL, 753 "Invalid adi,reference value for %s, should be less than %d.\n", 754 node_name, MAX11410_REFSEL_MAX + 1); 755 756 if (!max11410_get_vrefp(st, reference) || 757 (!max11410_get_vrefn(st, reference) && reference <= 2)) 758 return dev_err_probe(&indio_dev->dev, -EINVAL, 759 "Invalid VREF configuration for %s, either specify corresponding VREF regulators or change adi,reference property.\n", 760 node_name); 761 762 sig_path = MAX11410_PGA_SIG_PATH_BUFFERED; 763 fwnode_property_read_u32(child, "adi,input-mode", &sig_path); 764 if (sig_path > MAX11410_SIG_PATH_MAX) 765 return dev_err_probe(&indio_dev->dev, -EINVAL, 766 "Invalid adi,input-mode value for %s, should be less than %d.\n", 767 node_name, MAX11410_SIG_PATH_MAX + 1); 768 769 fwnode_property_read_u32(child, "settling-time-us", 770 &cfg->settling_time_us); 771 cfg->bipolar = fwnode_property_read_bool(child, "bipolar"); 772 cfg->buffered_vrefp = fwnode_property_read_bool(child, "adi,buffered-vrefp"); 773 cfg->buffered_vrefn = fwnode_property_read_bool(child, "adi,buffered-vrefn"); 774 cfg->refsel = reference; 775 cfg->sig_path = sig_path; 776 cfg->gain = 0; 777 778 /* Enable scale_available property if input mode is PGA */ 779 if (sig_path == MAX11410_PGA_SIG_PATH_PGA) { 780 __set_bit(IIO_CHAN_INFO_SCALE, 781 &chanspec.info_mask_separate_available); 782 cfg->scale_avail = devm_kcalloc(dev, MAX11410_SCALE_AVAIL_SIZE * 2, 783 sizeof(*cfg->scale_avail), 784 GFP_KERNEL); 785 if (!cfg->scale_avail) 786 return -ENOMEM; 787 788 scale = max11410_get_scale(st, *cfg); 789 for (i = 0; i < MAX11410_SCALE_AVAIL_SIZE; i++) { 790 cfg->scale_avail[2 * i] = scale >> i; 791 cfg->scale_avail[2 * i + 1] = chanspec.scan_type.realbits; 792 } 793 } else { 794 __clear_bit(IIO_CHAN_INFO_SCALE, 795 &chanspec.info_mask_separate_available); 796 } 797 798 chanspec.address = chan_idx; 799 chanspec.scan_index = chan_idx; 800 chanspec.channel = inputs[0]; 801 chanspec.channel2 = inputs[1]; 802 803 channels[chan_idx] = chanspec; 804 chan_idx++; 805 } 806 807 channels[chan_idx] = (struct iio_chan_spec)IIO_CHAN_SOFT_TIMESTAMP(chan_idx); 808 809 indio_dev->num_channels = chan_idx + 1; 810 indio_dev->channels = channels; 811 812 return 0; 813 } 814 815 static void max11410_disable_reg(void *reg) 816 { 817 regulator_disable(reg); 818 } 819 820 static int max11410_init_vref(struct device *dev, 821 struct regulator **vref, 822 const char *id) 823 { 824 struct regulator *reg; 825 int ret; 826 827 reg = devm_regulator_get_optional(dev, id); 828 if (PTR_ERR(reg) == -ENODEV) { 829 *vref = NULL; 830 return 0; 831 } else if (IS_ERR(reg)) { 832 return PTR_ERR(reg); 833 } 834 ret = regulator_enable(reg); 835 if (ret) 836 return dev_err_probe(dev, ret, 837 "Failed to enable regulator %s\n", id); 838 839 *vref = reg; 840 return devm_add_action_or_reset(dev, max11410_disable_reg, reg); 841 } 842 843 static int max11410_calibrate(struct max11410_state *st, u32 cal_type) 844 { 845 int ret, ret2, val; 846 847 ret = max11410_write_reg(st, MAX11410_REG_CAL_START, cal_type); 848 if (ret) 849 return ret; 850 851 /* Wait for status register Calibration Ready flag */ 852 ret = read_poll_timeout(max11410_read_reg, ret2, 853 ret2 || (val & MAX11410_STATUS_CAL_READY_BIT), 854 50000, MAX11410_CALIB_TIMEOUT_MS * 1000, true, 855 st, MAX11410_REG_STATUS, &val); 856 if (ret) 857 return ret; 858 859 return ret2; 860 } 861 862 static int max11410_self_calibrate(struct max11410_state *st) 863 { 864 int ret, i; 865 866 ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, 867 MAX11410_FILTER_RATE_MASK, 868 FIELD_PREP(MAX11410_FILTER_RATE_MASK, 869 MAX11410_FILTER_RATE_MAX)); 870 if (ret) 871 return ret; 872 873 ret = max11410_calibrate(st, MAX11410_CAL_START_SELF); 874 if (ret) 875 return ret; 876 877 ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, 878 MAX11410_PGA_SIG_PATH_MASK, 879 FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, 880 MAX11410_PGA_SIG_PATH_PGA)); 881 if (ret) 882 return ret; 883 884 /* PGA calibrations */ 885 for (i = 1; i < 8; ++i) { 886 ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, 887 MAX11410_PGA_GAIN_MASK, i); 888 if (ret) 889 return ret; 890 891 ret = max11410_calibrate(st, MAX11410_CAL_START_PGA); 892 if (ret) 893 return ret; 894 } 895 896 /* Cleanup */ 897 ret = regmap_write_bits(st->regmap, MAX11410_REG_PGA, 898 MAX11410_PGA_GAIN_MASK, 0); 899 if (ret) 900 return ret; 901 902 ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER, 903 MAX11410_FILTER_RATE_MASK, 0); 904 if (ret) 905 return ret; 906 907 return regmap_write_bits(st->regmap, MAX11410_REG_PGA, 908 MAX11410_PGA_SIG_PATH_MASK, 909 FIELD_PREP(MAX11410_PGA_SIG_PATH_MASK, 910 MAX11410_PGA_SIG_PATH_BUFFERED)); 911 } 912 913 static int max11410_probe(struct spi_device *spi) 914 { 915 const char *vrefp_regs[] = { "vref0p", "vref1p", "vref2p" }; 916 const char *vrefn_regs[] = { "vref0n", "vref1n", "vref2n" }; 917 struct device *dev = &spi->dev; 918 struct max11410_state *st; 919 struct iio_dev *indio_dev; 920 int ret, irqs[2]; 921 int i; 922 923 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 924 if (!indio_dev) 925 return -ENOMEM; 926 927 st = iio_priv(indio_dev); 928 st->spi_dev = spi; 929 init_completion(&st->completion); 930 mutex_init(&st->lock); 931 932 indio_dev->name = "max11410"; 933 indio_dev->modes = INDIO_DIRECT_MODE; 934 indio_dev->info = &max11410_info; 935 936 st->regmap = devm_regmap_init_spi(spi, ®map_config); 937 if (IS_ERR(st->regmap)) 938 return dev_err_probe(dev, PTR_ERR(st->regmap), 939 "regmap initialization failed\n"); 940 941 ret = max11410_init_vref(dev, &st->avdd, "avdd"); 942 if (ret) 943 return ret; 944 945 for (i = 0; i < ARRAY_SIZE(vrefp_regs); i++) { 946 ret = max11410_init_vref(dev, &st->vrefp[i], vrefp_regs[i]); 947 if (ret) 948 return ret; 949 950 ret = max11410_init_vref(dev, &st->vrefn[i], vrefn_regs[i]); 951 if (ret) 952 return ret; 953 } 954 955 /* 956 * Regulators must be configured before parsing channels for 957 * validating "adi,reference" property of each channel. 958 */ 959 ret = max11410_parse_channels(st, indio_dev); 960 if (ret) 961 return ret; 962 963 irqs[0] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio0"); 964 irqs[1] = fwnode_irq_get_byname(dev_fwnode(dev), "gpio1"); 965 966 if (irqs[0] > 0) { 967 st->irq = irqs[0]; 968 ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(0), 969 MAX11410_GPIO_INTRB); 970 } else if (irqs[1] > 0) { 971 st->irq = irqs[1]; 972 ret = regmap_write(st->regmap, MAX11410_REG_GPIO_CTRL(1), 973 MAX11410_GPIO_INTRB); 974 } else if (spi->irq > 0) { 975 return dev_err_probe(dev, -ENODEV, 976 "no interrupt name specified"); 977 } 978 979 if (ret) 980 return ret; 981 982 ret = regmap_set_bits(st->regmap, MAX11410_REG_CTRL, 983 MAX11410_CTRL_FORMAT_BIT); 984 if (ret) 985 return ret; 986 987 ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, 988 &max11410_trigger_handler, 989 &max11410_buffer_ops); 990 if (ret) 991 return ret; 992 993 if (st->irq > 0) { 994 st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", 995 indio_dev->name, 996 iio_device_id(indio_dev)); 997 if (!st->trig) 998 return -ENOMEM; 999 1000 st->trig->ops = &max11410_trigger_ops; 1001 ret = devm_iio_trigger_register(dev, st->trig); 1002 if (ret) 1003 return ret; 1004 1005 ret = devm_request_threaded_irq(dev, st->irq, NULL, 1006 &max11410_interrupt, 1007 IRQF_ONESHOT, "max11410", 1008 indio_dev); 1009 if (ret) 1010 return ret; 1011 } 1012 1013 ret = max11410_self_calibrate(st); 1014 if (ret) 1015 return dev_err_probe(dev, ret, 1016 "cannot perform device self calibration\n"); 1017 1018 return devm_iio_device_register(dev, indio_dev); 1019 } 1020 1021 static const struct of_device_id max11410_spi_of_id[] = { 1022 { .compatible = "adi,max11410" }, 1023 { } 1024 }; 1025 MODULE_DEVICE_TABLE(of, max11410_spi_of_id); 1026 1027 static const struct spi_device_id max11410_id[] = { 1028 { "max11410" }, 1029 { } 1030 }; 1031 MODULE_DEVICE_TABLE(spi, max11410_id); 1032 1033 static struct spi_driver max11410_driver = { 1034 .driver = { 1035 .name = "max11410", 1036 .of_match_table = max11410_spi_of_id, 1037 }, 1038 .probe = max11410_probe, 1039 .id_table = max11410_id, 1040 }; 1041 module_spi_driver(max11410_driver); 1042 1043 MODULE_AUTHOR("David Jung <David.Jung@analog.com>"); 1044 MODULE_AUTHOR("Ibrahim Tilki <Ibrahim.Tilki@analog.com>"); 1045 MODULE_DESCRIPTION("Analog Devices MAX11410 ADC"); 1046 MODULE_LICENSE("GPL"); 1047