1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Support code for Analog Devices Sigma-Delta ADCs 4 * 5 * Copyright 2012 Analog Devices Inc. 6 * Author: Lars-Peter Clausen <lars@metafoo.de> 7 */ 8 9 #include <linux/align.h> 10 #include <linux/interrupt.h> 11 #include <linux/device.h> 12 #include <linux/kernel.h> 13 #include <linux/slab.h> 14 #include <linux/spi/spi.h> 15 #include <linux/err.h> 16 #include <linux/module.h> 17 18 #include <linux/iio/iio.h> 19 #include <linux/iio/sysfs.h> 20 #include <linux/iio/buffer.h> 21 #include <linux/iio/trigger.h> 22 #include <linux/iio/trigger_consumer.h> 23 #include <linux/iio/triggered_buffer.h> 24 #include <linux/iio/adc/ad_sigma_delta.h> 25 26 #include <linux/unaligned.h> 27 28 29 #define AD_SD_COMM_CHAN_MASK 0x3 30 31 #define AD_SD_REG_COMM 0x00 32 #define AD_SD_REG_STATUS 0x00 33 #define AD_SD_REG_DATA 0x03 34 35 #define AD_SD_REG_STATUS_RDY 0x80 36 37 /** 38 * ad_sd_set_comm() - Set communications register 39 * 40 * @sigma_delta: The sigma delta device 41 * @comm: New value for the communications register 42 */ 43 void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm) 44 { 45 /* Some variants use the lower two bits of the communications register 46 * to select the channel */ 47 sigma_delta->comm = comm & AD_SD_COMM_CHAN_MASK; 48 } 49 EXPORT_SYMBOL_NS_GPL(ad_sd_set_comm, "IIO_AD_SIGMA_DELTA"); 50 51 /** 52 * ad_sd_write_reg() - Write a register 53 * 54 * @sigma_delta: The sigma delta device 55 * @reg: Address of the register 56 * @size: Size of the register (0-3) 57 * @val: Value to write to the register 58 * 59 * Returns 0 on success, an error code otherwise. 60 **/ 61 int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg, 62 unsigned int size, unsigned int val) 63 { 64 uint8_t *data = sigma_delta->tx_buf; 65 struct spi_transfer t = { 66 .tx_buf = data, 67 .len = size + 1, 68 .cs_change = sigma_delta->keep_cs_asserted, 69 }; 70 struct spi_message m; 71 int ret; 72 73 data[0] = (reg << sigma_delta->info->addr_shift) | sigma_delta->comm; 74 75 switch (size) { 76 case 3: 77 put_unaligned_be24(val, &data[1]); 78 break; 79 case 2: 80 put_unaligned_be16(val, &data[1]); 81 break; 82 case 1: 83 data[1] = val; 84 break; 85 case 0: 86 break; 87 default: 88 return -EINVAL; 89 } 90 91 spi_message_init(&m); 92 spi_message_add_tail(&t, &m); 93 94 if (sigma_delta->bus_locked) 95 ret = spi_sync_locked(sigma_delta->spi, &m); 96 else 97 ret = spi_sync(sigma_delta->spi, &m); 98 99 return ret; 100 } 101 EXPORT_SYMBOL_NS_GPL(ad_sd_write_reg, "IIO_AD_SIGMA_DELTA"); 102 103 static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta, 104 unsigned int reg, unsigned int size, uint8_t *val) 105 { 106 uint8_t *data = sigma_delta->tx_buf; 107 int ret; 108 struct spi_transfer t[] = { 109 { 110 .tx_buf = data, 111 .len = 1, 112 }, { 113 .rx_buf = val, 114 .len = size, 115 .cs_change = sigma_delta->keep_cs_asserted, 116 }, 117 }; 118 struct spi_message m; 119 120 spi_message_init(&m); 121 122 if (sigma_delta->info->has_registers) { 123 data[0] = reg << sigma_delta->info->addr_shift; 124 data[0] |= sigma_delta->info->read_mask; 125 data[0] |= sigma_delta->comm; 126 spi_message_add_tail(&t[0], &m); 127 } 128 spi_message_add_tail(&t[1], &m); 129 130 if (sigma_delta->bus_locked) 131 ret = spi_sync_locked(sigma_delta->spi, &m); 132 else 133 ret = spi_sync(sigma_delta->spi, &m); 134 135 return ret; 136 } 137 138 /** 139 * ad_sd_read_reg() - Read a register 140 * 141 * @sigma_delta: The sigma delta device 142 * @reg: Address of the register 143 * @size: Size of the register (1-4) 144 * @val: Read value 145 * 146 * Returns 0 on success, an error code otherwise. 147 **/ 148 int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, 149 unsigned int reg, unsigned int size, unsigned int *val) 150 { 151 int ret; 152 153 ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->rx_buf); 154 if (ret < 0) 155 goto out; 156 157 switch (size) { 158 case 4: 159 *val = get_unaligned_be32(sigma_delta->rx_buf); 160 break; 161 case 3: 162 *val = get_unaligned_be24(sigma_delta->rx_buf); 163 break; 164 case 2: 165 *val = get_unaligned_be16(sigma_delta->rx_buf); 166 break; 167 case 1: 168 *val = sigma_delta->rx_buf[0]; 169 break; 170 default: 171 ret = -EINVAL; 172 break; 173 } 174 175 out: 176 return ret; 177 } 178 EXPORT_SYMBOL_NS_GPL(ad_sd_read_reg, "IIO_AD_SIGMA_DELTA"); 179 180 /** 181 * ad_sd_reset() - Reset the serial interface 182 * 183 * @sigma_delta: The sigma delta device 184 * 185 * Returns 0 on success, an error code otherwise. 186 **/ 187 int ad_sd_reset(struct ad_sigma_delta *sigma_delta) 188 { 189 unsigned int reset_length = sigma_delta->info->num_resetclks; 190 uint8_t *buf; 191 unsigned int size; 192 int ret; 193 194 size = DIV_ROUND_UP(reset_length, 8); 195 buf = kcalloc(size, sizeof(*buf), GFP_KERNEL); 196 if (!buf) 197 return -ENOMEM; 198 199 memset(buf, 0xff, size); 200 ret = spi_write(sigma_delta->spi, buf, size); 201 kfree(buf); 202 203 return ret; 204 } 205 EXPORT_SYMBOL_NS_GPL(ad_sd_reset, "IIO_AD_SIGMA_DELTA"); 206 207 static bool ad_sd_disable_irq(struct ad_sigma_delta *sigma_delta) 208 { 209 guard(spinlock_irqsave)(&sigma_delta->irq_lock); 210 211 /* It's already off, return false to indicate nothing was changed */ 212 if (sigma_delta->irq_dis) 213 return false; 214 215 sigma_delta->irq_dis = true; 216 disable_irq_nosync(sigma_delta->irq_line); 217 return true; 218 } 219 220 static void ad_sd_enable_irq(struct ad_sigma_delta *sigma_delta) 221 { 222 guard(spinlock_irqsave)(&sigma_delta->irq_lock); 223 224 sigma_delta->irq_dis = false; 225 enable_irq(sigma_delta->irq_line); 226 } 227 228 #define AD_SD_CLEAR_DATA_BUFLEN 9 229 230 /* Called with `sigma_delta->bus_locked == true` only. */ 231 static int ad_sigma_delta_clear_pending_event(struct ad_sigma_delta *sigma_delta) 232 { 233 bool pending_event; 234 unsigned int data_read_len = BITS_TO_BYTES(sigma_delta->info->num_resetclks); 235 u8 *data; 236 struct spi_transfer t[] = { 237 { 238 .len = 1, 239 }, { 240 .len = data_read_len, 241 } 242 }; 243 struct spi_message m; 244 int ret; 245 246 /* 247 * Read R̅D̅Y̅ pin (if possible) or status register to check if there is an 248 * old event. 249 */ 250 if (sigma_delta->rdy_gpiod) { 251 pending_event = gpiod_get_value(sigma_delta->rdy_gpiod); 252 } else { 253 unsigned int status_reg; 254 255 ret = ad_sd_read_reg(sigma_delta, AD_SD_REG_STATUS, 1, &status_reg); 256 if (ret) 257 return ret; 258 259 pending_event = !(status_reg & AD_SD_REG_STATUS_RDY); 260 } 261 262 if (!pending_event) 263 return 0; 264 265 /* 266 * In general the size of the data register is unknown. It varies from 267 * device to device, might be one byte longer if CONTROL.DATA_STATUS is 268 * set and even varies on some devices depending on which input is 269 * selected. So send one byte to start reading the data register and 270 * then just clock for some bytes with DIN (aka MOSI) high to not 271 * confuse the register access state machine after the data register was 272 * completely read. Note however that the sequence length must be 273 * shorter than the reset procedure. 274 */ 275 276 data = kzalloc(data_read_len + 1, GFP_KERNEL); 277 if (!data) 278 return -ENOMEM; 279 280 spi_message_init(&m); 281 if (sigma_delta->info->has_registers) { 282 unsigned int data_reg = sigma_delta->info->data_reg ?: AD_SD_REG_DATA; 283 284 data[0] = data_reg << sigma_delta->info->addr_shift; 285 data[0] |= sigma_delta->info->read_mask; 286 data[0] |= sigma_delta->comm; 287 t[0].tx_buf = data; 288 spi_message_add_tail(&t[0], &m); 289 } 290 291 /* 292 * The first transferred byte is part of the real data register, 293 * so this doesn't need to be 0xff. In the remaining 294 * `data_read_len - 1` bytes are less than $num_resetclks ones. 295 */ 296 t[1].tx_buf = data + 1; 297 data[1] = 0x00; 298 memset(data + 2, 0xff, data_read_len - 1); 299 spi_message_add_tail(&t[1], &m); 300 301 ret = spi_sync_locked(sigma_delta->spi, &m); 302 303 kfree(data); 304 305 return ret; 306 } 307 308 int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta, 309 unsigned int mode, unsigned int channel) 310 { 311 int ret; 312 unsigned long time_left; 313 314 ret = ad_sigma_delta_set_channel(sigma_delta, channel); 315 if (ret) 316 return ret; 317 318 spi_bus_lock(sigma_delta->spi->controller); 319 sigma_delta->bus_locked = true; 320 sigma_delta->keep_cs_asserted = true; 321 reinit_completion(&sigma_delta->completion); 322 323 ret = ad_sigma_delta_clear_pending_event(sigma_delta); 324 if (ret) 325 goto out; 326 327 ret = ad_sigma_delta_set_mode(sigma_delta, mode); 328 if (ret < 0) 329 goto out; 330 331 ad_sd_enable_irq(sigma_delta); 332 time_left = wait_for_completion_timeout(&sigma_delta->completion, 2 * HZ); 333 if (time_left == 0) { 334 ad_sd_disable_irq(sigma_delta); 335 ret = -EIO; 336 } else { 337 ret = 0; 338 } 339 out: 340 sigma_delta->keep_cs_asserted = false; 341 ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); 342 sigma_delta->bus_locked = false; 343 spi_bus_unlock(sigma_delta->spi->controller); 344 345 return ret; 346 } 347 EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate, "IIO_AD_SIGMA_DELTA"); 348 349 /** 350 * ad_sd_calibrate_all() - Performs channel calibration 351 * @sigma_delta: The sigma delta device 352 * @cb: Array of channels and calibration type to perform 353 * @n: Number of items in cb 354 * 355 * Returns 0 on success, an error code otherwise. 356 **/ 357 int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta, 358 const struct ad_sd_calib_data *cb, unsigned int n) 359 { 360 unsigned int i; 361 int ret; 362 363 for (i = 0; i < n; i++) { 364 ret = ad_sd_calibrate(sigma_delta, cb[i].mode, cb[i].channel); 365 if (ret) 366 return ret; 367 } 368 369 return 0; 370 } 371 EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate_all, "IIO_AD_SIGMA_DELTA"); 372 373 /** 374 * ad_sigma_delta_single_conversion() - Performs a single data conversion 375 * @indio_dev: The IIO device 376 * @chan: The conversion is done for this channel 377 * @val: Pointer to the location where to store the read value 378 * 379 * Returns: 0 on success, an error value otherwise. 380 */ 381 int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev, 382 const struct iio_chan_spec *chan, int *val) 383 { 384 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 385 unsigned int sample, raw_sample; 386 unsigned int data_reg; 387 int ret = 0; 388 389 ret = iio_device_claim_direct_mode(indio_dev); 390 if (ret) 391 return ret; 392 393 ad_sigma_delta_set_channel(sigma_delta, chan->address); 394 395 spi_bus_lock(sigma_delta->spi->controller); 396 sigma_delta->bus_locked = true; 397 sigma_delta->keep_cs_asserted = true; 398 reinit_completion(&sigma_delta->completion); 399 400 ret = ad_sigma_delta_clear_pending_event(sigma_delta); 401 if (ret) 402 goto out_unlock; 403 404 ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_SINGLE); 405 406 ad_sd_enable_irq(sigma_delta); 407 ret = wait_for_completion_interruptible_timeout( 408 &sigma_delta->completion, HZ); 409 410 if (ret == 0) 411 ret = -EIO; 412 if (ret < 0) 413 goto out; 414 415 if (sigma_delta->info->data_reg != 0) 416 data_reg = sigma_delta->info->data_reg; 417 else 418 data_reg = AD_SD_REG_DATA; 419 420 ret = ad_sd_read_reg(sigma_delta, data_reg, 421 DIV_ROUND_UP(chan->scan_type.realbits + chan->scan_type.shift, 8), 422 &raw_sample); 423 424 out: 425 ad_sd_disable_irq(sigma_delta); 426 427 ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); 428 ad_sigma_delta_disable_one(sigma_delta, chan->address); 429 430 out_unlock: 431 sigma_delta->keep_cs_asserted = false; 432 sigma_delta->bus_locked = false; 433 spi_bus_unlock(sigma_delta->spi->controller); 434 iio_device_release_direct_mode(indio_dev); 435 436 if (ret) 437 return ret; 438 439 sample = raw_sample >> chan->scan_type.shift; 440 sample &= (1 << chan->scan_type.realbits) - 1; 441 *val = sample; 442 443 ret = ad_sigma_delta_postprocess_sample(sigma_delta, raw_sample); 444 if (ret) 445 return ret; 446 447 return IIO_VAL_INT; 448 } 449 EXPORT_SYMBOL_NS_GPL(ad_sigma_delta_single_conversion, "IIO_AD_SIGMA_DELTA"); 450 451 static int ad_sd_buffer_postenable(struct iio_dev *indio_dev) 452 { 453 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 454 unsigned int i, slot, samples_buf_size; 455 unsigned int channel; 456 uint8_t *samples_buf; 457 int ret; 458 459 if (sigma_delta->num_slots == 1) { 460 channel = find_first_bit(indio_dev->active_scan_mask, 461 iio_get_masklength(indio_dev)); 462 ret = ad_sigma_delta_set_channel(sigma_delta, 463 indio_dev->channels[channel].address); 464 if (ret) 465 return ret; 466 slot = 1; 467 } else { 468 /* 469 * At this point update_scan_mode already enabled the required channels. 470 * For sigma-delta sequencer drivers with multiple slots, an update_scan_mode 471 * implementation is mandatory. 472 */ 473 slot = 0; 474 iio_for_each_active_channel(indio_dev, i) { 475 sigma_delta->slots[slot] = indio_dev->channels[i].address; 476 slot++; 477 } 478 } 479 480 sigma_delta->active_slots = slot; 481 sigma_delta->current_slot = 0; 482 483 if (sigma_delta->active_slots > 1) { 484 ret = ad_sigma_delta_append_status(sigma_delta, true); 485 if (ret) 486 return ret; 487 } 488 489 samples_buf_size = ALIGN(slot * indio_dev->channels[0].scan_type.storagebits, 8); 490 samples_buf_size += sizeof(int64_t); 491 samples_buf = devm_krealloc(&sigma_delta->spi->dev, sigma_delta->samples_buf, 492 samples_buf_size, GFP_KERNEL); 493 if (!samples_buf) 494 return -ENOMEM; 495 496 sigma_delta->samples_buf = samples_buf; 497 498 spi_bus_lock(sigma_delta->spi->controller); 499 sigma_delta->bus_locked = true; 500 sigma_delta->keep_cs_asserted = true; 501 502 ret = ad_sigma_delta_clear_pending_event(sigma_delta); 503 if (ret) 504 goto err_unlock; 505 506 ret = ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_CONTINUOUS); 507 if (ret) 508 goto err_unlock; 509 510 ad_sd_enable_irq(sigma_delta); 511 512 return 0; 513 514 err_unlock: 515 spi_bus_unlock(sigma_delta->spi->controller); 516 517 return ret; 518 } 519 520 static int ad_sd_buffer_postdisable(struct iio_dev *indio_dev) 521 { 522 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 523 524 reinit_completion(&sigma_delta->completion); 525 wait_for_completion_timeout(&sigma_delta->completion, HZ); 526 527 ad_sd_disable_irq(sigma_delta); 528 529 sigma_delta->keep_cs_asserted = false; 530 ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); 531 532 if (sigma_delta->status_appended) 533 ad_sigma_delta_append_status(sigma_delta, false); 534 535 ad_sigma_delta_disable_all(sigma_delta); 536 sigma_delta->bus_locked = false; 537 return spi_bus_unlock(sigma_delta->spi->controller); 538 } 539 540 static irqreturn_t ad_sd_trigger_handler(int irq, void *p) 541 { 542 struct iio_poll_func *pf = p; 543 struct iio_dev *indio_dev = pf->indio_dev; 544 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 545 uint8_t *data = sigma_delta->rx_buf; 546 unsigned int transfer_size; 547 unsigned int sample_size; 548 unsigned int sample_pos; 549 unsigned int status_pos; 550 unsigned int reg_size; 551 unsigned int data_reg; 552 553 reg_size = indio_dev->channels[0].scan_type.realbits + 554 indio_dev->channels[0].scan_type.shift; 555 reg_size = DIV_ROUND_UP(reg_size, 8); 556 557 if (sigma_delta->info->data_reg != 0) 558 data_reg = sigma_delta->info->data_reg; 559 else 560 data_reg = AD_SD_REG_DATA; 561 562 /* Status word will be appended to the sample during transfer */ 563 if (sigma_delta->status_appended) 564 transfer_size = reg_size + 1; 565 else 566 transfer_size = reg_size; 567 568 switch (reg_size) { 569 case 4: 570 case 2: 571 case 1: 572 status_pos = reg_size; 573 ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[0]); 574 break; 575 case 3: 576 /* 577 * Data array after transfer will look like (if status is appended): 578 * data[] = { [0][sample][sample][sample][status] } 579 * Keeping the first byte 0 shifts the status position by 1 byte to the right. 580 */ 581 status_pos = reg_size + 1; 582 583 /* We store 24 bit samples in a 32 bit word. Keep the upper 584 * byte set to zero. */ 585 ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[1]); 586 break; 587 } 588 589 /* 590 * For devices sampling only one channel at 591 * once, there is no need for sample number tracking. 592 */ 593 if (sigma_delta->active_slots == 1) { 594 iio_push_to_buffers_with_timestamp(indio_dev, data, pf->timestamp); 595 goto irq_handled; 596 } 597 598 if (sigma_delta->status_appended) { 599 u8 converted_channel; 600 601 converted_channel = data[status_pos] & sigma_delta->info->status_ch_mask; 602 if (converted_channel != sigma_delta->slots[sigma_delta->current_slot]) { 603 /* 604 * Desync occurred during continuous sampling of multiple channels. 605 * Drop this incomplete sample and start from first channel again. 606 */ 607 608 sigma_delta->current_slot = 0; 609 goto irq_handled; 610 } 611 } 612 613 sample_size = indio_dev->channels[0].scan_type.storagebits / 8; 614 sample_pos = sample_size * sigma_delta->current_slot; 615 memcpy(&sigma_delta->samples_buf[sample_pos], data, sample_size); 616 sigma_delta->current_slot++; 617 618 if (sigma_delta->current_slot == sigma_delta->active_slots) { 619 sigma_delta->current_slot = 0; 620 iio_push_to_buffers_with_timestamp(indio_dev, sigma_delta->samples_buf, 621 pf->timestamp); 622 } 623 624 irq_handled: 625 iio_trigger_notify_done(indio_dev->trig); 626 ad_sd_enable_irq(sigma_delta); 627 628 return IRQ_HANDLED; 629 } 630 631 static bool ad_sd_validate_scan_mask(struct iio_dev *indio_dev, const unsigned long *mask) 632 { 633 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 634 635 return bitmap_weight(mask, iio_get_masklength(indio_dev)) <= sigma_delta->num_slots; 636 } 637 638 static const struct iio_buffer_setup_ops ad_sd_buffer_setup_ops = { 639 .postenable = &ad_sd_buffer_postenable, 640 .postdisable = &ad_sd_buffer_postdisable, 641 .validate_scan_mask = &ad_sd_validate_scan_mask, 642 }; 643 644 static irqreturn_t ad_sd_data_rdy_trig_poll(int irq, void *private) 645 { 646 struct ad_sigma_delta *sigma_delta = private; 647 648 /* 649 * AD7124 and a few others use the same physical line for interrupt 650 * reporting (R̅D̅Y̅) and MISO. 651 * As MISO toggles when reading a register, this likely results in a 652 * pending interrupt. This has two consequences: a) The irq might 653 * trigger immediately after it's enabled even though the conversion 654 * isn't done yet; and b) checking the STATUS register's R̅D̅Y̅ flag is 655 * off-limits as reading that would trigger another irq event. 656 * 657 * So read the MOSI line as GPIO (if available) and only trigger the irq 658 * if the line is active. Without such a GPIO assume this is a valid 659 * interrupt. 660 * 661 * Also as disable_irq_nosync() is used to disable the irq, only act if 662 * the irq wasn't disabled before. 663 */ 664 if ((!sigma_delta->rdy_gpiod || gpiod_get_value(sigma_delta->rdy_gpiod)) && 665 ad_sd_disable_irq(sigma_delta)) { 666 complete(&sigma_delta->completion); 667 iio_trigger_poll(sigma_delta->trig); 668 669 return IRQ_HANDLED; 670 } 671 672 return IRQ_NONE; 673 } 674 675 /** 676 * ad_sd_validate_trigger() - validate_trigger callback for ad_sigma_delta devices 677 * @indio_dev: The IIO device 678 * @trig: The new trigger 679 * 680 * Returns: 0 if the 'trig' matches the trigger registered by the ad_sigma_delta 681 * device, -EINVAL otherwise. 682 */ 683 int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig) 684 { 685 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 686 687 if (sigma_delta->trig != trig) 688 return -EINVAL; 689 690 return 0; 691 } 692 EXPORT_SYMBOL_NS_GPL(ad_sd_validate_trigger, "IIO_AD_SIGMA_DELTA"); 693 694 static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_dev) 695 { 696 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 697 unsigned long irq_flags = irq_get_trigger_type(sigma_delta->irq_line); 698 int ret; 699 700 if (dev != &sigma_delta->spi->dev) { 701 dev_err(dev, "Trigger parent should be '%s', got '%s'\n", 702 dev_name(dev), dev_name(&sigma_delta->spi->dev)); 703 return -EFAULT; 704 } 705 706 sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, 707 iio_device_id(indio_dev)); 708 if (sigma_delta->trig == NULL) 709 return -ENOMEM; 710 711 init_completion(&sigma_delta->completion); 712 713 sigma_delta->irq_dis = true; 714 715 /* the IRQ core clears IRQ_DISABLE_UNLAZY flag when freeing an IRQ */ 716 irq_set_status_flags(sigma_delta->irq_line, IRQ_DISABLE_UNLAZY); 717 718 /* Allow overwriting the flags from firmware */ 719 if (!irq_flags) 720 irq_flags = sigma_delta->info->irq_flags; 721 722 ret = devm_request_irq(dev, sigma_delta->irq_line, 723 ad_sd_data_rdy_trig_poll, 724 irq_flags | IRQF_NO_AUTOEN, 725 indio_dev->name, 726 sigma_delta); 727 if (ret) 728 return ret; 729 730 iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta); 731 732 ret = devm_iio_trigger_register(dev, sigma_delta->trig); 733 if (ret) 734 return ret; 735 736 /* select default trigger */ 737 indio_dev->trig = iio_trigger_get(sigma_delta->trig); 738 739 return 0; 740 } 741 742 /** 743 * devm_ad_sd_setup_buffer_and_trigger() - Device-managed buffer & trigger setup 744 * @dev: Device object to which to bind the life-time of the resources attached 745 * @indio_dev: The IIO device 746 */ 747 int devm_ad_sd_setup_buffer_and_trigger(struct device *dev, struct iio_dev *indio_dev) 748 { 749 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 750 int ret; 751 752 sigma_delta->slots = devm_kcalloc(dev, sigma_delta->num_slots, 753 sizeof(*sigma_delta->slots), GFP_KERNEL); 754 if (!sigma_delta->slots) 755 return -ENOMEM; 756 757 ret = devm_iio_triggered_buffer_setup(dev, indio_dev, 758 &iio_pollfunc_store_time, 759 &ad_sd_trigger_handler, 760 &ad_sd_buffer_setup_ops); 761 if (ret) 762 return ret; 763 764 return devm_ad_sd_probe_trigger(dev, indio_dev); 765 } 766 EXPORT_SYMBOL_NS_GPL(devm_ad_sd_setup_buffer_and_trigger, "IIO_AD_SIGMA_DELTA"); 767 768 /** 769 * ad_sd_init() - Initializes a ad_sigma_delta struct 770 * @sigma_delta: The ad_sigma_delta device 771 * @indio_dev: The IIO device which the Sigma Delta device is used for 772 * @spi: The SPI device for the ad_sigma_delta device 773 * @info: Device specific callbacks and options 774 * 775 * This function needs to be called before any other operations are performed on 776 * the ad_sigma_delta struct. 777 */ 778 int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev, 779 struct spi_device *spi, const struct ad_sigma_delta_info *info) 780 { 781 sigma_delta->spi = spi; 782 sigma_delta->info = info; 783 784 /* If the field is unset in ad_sigma_delta_info, assume there can only be 1 slot. */ 785 if (!info->num_slots) 786 sigma_delta->num_slots = 1; 787 else 788 sigma_delta->num_slots = info->num_slots; 789 790 if (sigma_delta->num_slots > 1) { 791 if (!indio_dev->info->update_scan_mode) { 792 dev_err(&spi->dev, "iio_dev lacks update_scan_mode().\n"); 793 return -EINVAL; 794 } 795 796 if (!info->disable_all) { 797 dev_err(&spi->dev, "ad_sigma_delta_info lacks disable_all().\n"); 798 return -EINVAL; 799 } 800 } 801 802 spin_lock_init(&sigma_delta->irq_lock); 803 804 if (info->irq_line) 805 sigma_delta->irq_line = info->irq_line; 806 else 807 sigma_delta->irq_line = spi->irq; 808 809 sigma_delta->rdy_gpiod = devm_gpiod_get_optional(&spi->dev, "rdy", GPIOD_IN); 810 if (IS_ERR(sigma_delta->rdy_gpiod)) 811 return dev_err_probe(&spi->dev, PTR_ERR(sigma_delta->rdy_gpiod), 812 "Failed to find rdy gpio\n"); 813 814 if (sigma_delta->rdy_gpiod && !sigma_delta->irq_line) { 815 sigma_delta->irq_line = gpiod_to_irq(sigma_delta->rdy_gpiod); 816 if (sigma_delta->irq_line < 0) 817 return sigma_delta->irq_line; 818 } 819 820 iio_device_set_drvdata(indio_dev, sigma_delta); 821 822 return 0; 823 } 824 EXPORT_SYMBOL_NS_GPL(ad_sd_init, "IIO_AD_SIGMA_DELTA"); 825 826 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 827 MODULE_DESCRIPTION("Analog Devices Sigma-Delta ADCs"); 828 MODULE_LICENSE("GPL v2"); 829