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1// SPDX-License-Identifier: GPL-2.02/*3 * AD7606 SPI ADC driver4 *5 * Copyright 2011 Analog Devices Inc.6 */7 8#include <linux/delay.h>9#include <linux/device.h>10#include <linux/err.h>11#include <linux/gpio/consumer.h>12#include <linux/interrupt.h>13#include <linux/kernel.h>14#include <linux/module.h>15#include <linux/property.h>16#include <linux/regulator/consumer.h>17#include <linux/sched.h>18#include <linux/slab.h>19#include <linux/sysfs.h>20#include <linux/util_macros.h>21 22#include <linux/iio/iio.h>23#include <linux/iio/buffer.h>24#include <linux/iio/sysfs.h>25#include <linux/iio/trigger.h>26#include <linux/iio/triggered_buffer.h>27#include <linux/iio/trigger_consumer.h>28 29#include "ad7606.h"30 31/*32 * Scales are computed as 5000/32768 and 10000/32768 respectively,33 * so that when applied to the raw values they provide mV values34 */35static const unsigned int ad7606_scale_avail[2] = {36 152588, 30517637};38 39 40static const unsigned int ad7616_sw_scale_avail[3] = {41 76293, 152588, 30517642};43 44static const unsigned int ad7606_oversampling_avail[7] = {45 1, 2, 4, 8, 16, 32, 64,46};47 48static const unsigned int ad7616_oversampling_avail[8] = {49 1, 2, 4, 8, 16, 32, 64, 128,50};51 52int ad7606_reset(struct ad7606_state *st)53{54 if (st->gpio_reset) {55 gpiod_set_value(st->gpio_reset, 1);56 ndelay(100); /* t_reset >= 100ns */57 gpiod_set_value(st->gpio_reset, 0);58 return 0;59 }60 61 return -ENODEV;62}63EXPORT_SYMBOL_NS_GPL(ad7606_reset, IIO_AD7606);64 65static int ad7606_reg_access(struct iio_dev *indio_dev,66 unsigned int reg,67 unsigned int writeval,68 unsigned int *readval)69{70 struct ad7606_state *st = iio_priv(indio_dev);71 int ret;72 73 guard(mutex)(&st->lock);74 75 if (readval) {76 ret = st->bops->reg_read(st, reg);77 if (ret < 0)78 return ret;79 *readval = ret;80 return 0;81 } else {82 return st->bops->reg_write(st, reg, writeval);83 }84}85 86static int ad7606_read_samples(struct ad7606_state *st)87{88 unsigned int num = st->chip_info->num_channels - 1;89 u16 *data = st->data;90 91 return st->bops->read_block(st->dev, num, data);92}93 94static irqreturn_t ad7606_trigger_handler(int irq, void *p)95{96 struct iio_poll_func *pf = p;97 struct iio_dev *indio_dev = pf->indio_dev;98 struct ad7606_state *st = iio_priv(indio_dev);99 int ret;100 101 guard(mutex)(&st->lock);102 103 ret = ad7606_read_samples(st);104 if (ret)105 goto error_ret;106 107 iio_push_to_buffers_with_timestamp(indio_dev, st->data,108 iio_get_time_ns(indio_dev));109error_ret:110 iio_trigger_notify_done(indio_dev->trig);111 /* The rising edge of the CONVST signal starts a new conversion. */112 gpiod_set_value(st->gpio_convst, 1);113 114 return IRQ_HANDLED;115}116 117static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch)118{119 struct ad7606_state *st = iio_priv(indio_dev);120 int ret;121 122 gpiod_set_value(st->gpio_convst, 1);123 ret = wait_for_completion_timeout(&st->completion,124 msecs_to_jiffies(1000));125 if (!ret) {126 ret = -ETIMEDOUT;127 goto error_ret;128 }129 130 ret = ad7606_read_samples(st);131 if (ret == 0)132 ret = st->data[ch];133 134error_ret:135 gpiod_set_value(st->gpio_convst, 0);136 137 return ret;138}139 140static int ad7606_read_raw(struct iio_dev *indio_dev,141 struct iio_chan_spec const *chan,142 int *val,143 int *val2,144 long m)145{146 int ret, ch = 0;147 struct ad7606_state *st = iio_priv(indio_dev);148 149 switch (m) {150 case IIO_CHAN_INFO_RAW:151 iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {152 ret = ad7606_scan_direct(indio_dev, chan->address);153 if (ret < 0)154 return ret;155 *val = (short) ret;156 return IIO_VAL_INT;157 }158 unreachable();159 case IIO_CHAN_INFO_SCALE:160 if (st->sw_mode_en)161 ch = chan->address;162 *val = 0;163 *val2 = st->scale_avail[st->range[ch]];164 return IIO_VAL_INT_PLUS_MICRO;165 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:166 *val = st->oversampling;167 return IIO_VAL_INT;168 }169 return -EINVAL;170}171 172static ssize_t ad7606_show_avail(char *buf, const unsigned int *vals,173 unsigned int n, bool micros)174{175 size_t len = 0;176 int i;177 178 for (i = 0; i < n; i++) {179 len += scnprintf(buf + len, PAGE_SIZE - len,180 micros ? "0.%06u " : "%u ", vals[i]);181 }182 buf[len - 1] = '\n';183 184 return len;185}186 187static ssize_t in_voltage_scale_available_show(struct device *dev,188 struct device_attribute *attr,189 char *buf)190{191 struct iio_dev *indio_dev = dev_to_iio_dev(dev);192 struct ad7606_state *st = iio_priv(indio_dev);193 194 return ad7606_show_avail(buf, st->scale_avail, st->num_scales, true);195}196 197static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);198 199static int ad7606_write_scale_hw(struct iio_dev *indio_dev, int ch, int val)200{201 struct ad7606_state *st = iio_priv(indio_dev);202 203 gpiod_set_value(st->gpio_range, val);204 205 return 0;206}207 208static int ad7606_write_os_hw(struct iio_dev *indio_dev, int val)209{210 struct ad7606_state *st = iio_priv(indio_dev);211 DECLARE_BITMAP(values, 3);212 213 values[0] = val & GENMASK(2, 0);214 215 gpiod_set_array_value(st->gpio_os->ndescs, st->gpio_os->desc,216 st->gpio_os->info, values);217 218 /* AD7616 requires a reset to update value */219 if (st->chip_info->os_req_reset)220 ad7606_reset(st);221 222 return 0;223}224 225static int ad7606_write_raw(struct iio_dev *indio_dev,226 struct iio_chan_spec const *chan,227 int val,228 int val2,229 long mask)230{231 struct ad7606_state *st = iio_priv(indio_dev);232 int i, ret, ch = 0;233 234 guard(mutex)(&st->lock);235 236 switch (mask) {237 case IIO_CHAN_INFO_SCALE:238 i = find_closest(val2, st->scale_avail, st->num_scales);239 if (st->sw_mode_en)240 ch = chan->address;241 ret = st->write_scale(indio_dev, ch, i);242 if (ret < 0)243 return ret;244 st->range[ch] = i;245 246 return 0;247 case IIO_CHAN_INFO_OVERSAMPLING_RATIO:248 if (val2)249 return -EINVAL;250 i = find_closest(val, st->oversampling_avail,251 st->num_os_ratios);252 ret = st->write_os(indio_dev, i);253 if (ret < 0)254 return ret;255 256 return 0;257 default:258 return -EINVAL;259 }260}261 262static ssize_t ad7606_oversampling_ratio_avail(struct device *dev,263 struct device_attribute *attr,264 char *buf)265{266 struct iio_dev *indio_dev = dev_to_iio_dev(dev);267 struct ad7606_state *st = iio_priv(indio_dev);268 269 return ad7606_show_avail(buf, st->oversampling_avail,270 st->num_os_ratios, false);271}272 273static IIO_DEVICE_ATTR(oversampling_ratio_available, 0444,274 ad7606_oversampling_ratio_avail, NULL, 0);275 276static struct attribute *ad7606_attributes_os_and_range[] = {277 &iio_dev_attr_in_voltage_scale_available.dev_attr.attr,278 &iio_dev_attr_oversampling_ratio_available.dev_attr.attr,279 NULL,280};281 282static const struct attribute_group ad7606_attribute_group_os_and_range = {283 .attrs = ad7606_attributes_os_and_range,284};285 286static struct attribute *ad7606_attributes_os[] = {287 &iio_dev_attr_oversampling_ratio_available.dev_attr.attr,288 NULL,289};290 291static const struct attribute_group ad7606_attribute_group_os = {292 .attrs = ad7606_attributes_os,293};294 295static struct attribute *ad7606_attributes_range[] = {296 &iio_dev_attr_in_voltage_scale_available.dev_attr.attr,297 NULL,298};299 300static const struct attribute_group ad7606_attribute_group_range = {301 .attrs = ad7606_attributes_range,302};303 304static const struct iio_chan_spec ad7605_channels[] = {305 IIO_CHAN_SOFT_TIMESTAMP(4),306 AD7605_CHANNEL(0),307 AD7605_CHANNEL(1),308 AD7605_CHANNEL(2),309 AD7605_CHANNEL(3),310};311 312static const struct iio_chan_spec ad7606_channels[] = {313 IIO_CHAN_SOFT_TIMESTAMP(8),314 AD7606_CHANNEL(0),315 AD7606_CHANNEL(1),316 AD7606_CHANNEL(2),317 AD7606_CHANNEL(3),318 AD7606_CHANNEL(4),319 AD7606_CHANNEL(5),320 AD7606_CHANNEL(6),321 AD7606_CHANNEL(7),322};323 324/*325 * The current assumption that this driver makes for AD7616, is that it's326 * working in Hardware Mode with Serial, Burst and Sequencer modes activated.327 * To activate them, following pins must be pulled high:328 * -SER/PAR329 * -SEQEN330 * And following pins must be pulled low:331 * -WR/BURST332 * -DB4/SER1W333 */334static const struct iio_chan_spec ad7616_channels[] = {335 IIO_CHAN_SOFT_TIMESTAMP(16),336 AD7606_CHANNEL(0),337 AD7606_CHANNEL(1),338 AD7606_CHANNEL(2),339 AD7606_CHANNEL(3),340 AD7606_CHANNEL(4),341 AD7606_CHANNEL(5),342 AD7606_CHANNEL(6),343 AD7606_CHANNEL(7),344 AD7606_CHANNEL(8),345 AD7606_CHANNEL(9),346 AD7606_CHANNEL(10),347 AD7606_CHANNEL(11),348 AD7606_CHANNEL(12),349 AD7606_CHANNEL(13),350 AD7606_CHANNEL(14),351 AD7606_CHANNEL(15),352};353 354static const struct ad7606_chip_info ad7606_chip_info_tbl[] = {355 /* More devices added in future */356 [ID_AD7605_4] = {357 .channels = ad7605_channels,358 .num_channels = 5,359 },360 [ID_AD7606_8] = {361 .channels = ad7606_channels,362 .num_channels = 9,363 .oversampling_avail = ad7606_oversampling_avail,364 .oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),365 },366 [ID_AD7606_6] = {367 .channels = ad7606_channels,368 .num_channels = 7,369 .oversampling_avail = ad7606_oversampling_avail,370 .oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),371 },372 [ID_AD7606_4] = {373 .channels = ad7606_channels,374 .num_channels = 5,375 .oversampling_avail = ad7606_oversampling_avail,376 .oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),377 },378 [ID_AD7606B] = {379 .channels = ad7606_channels,380 .num_channels = 9,381 .oversampling_avail = ad7606_oversampling_avail,382 .oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),383 },384 [ID_AD7616] = {385 .channels = ad7616_channels,386 .num_channels = 17,387 .oversampling_avail = ad7616_oversampling_avail,388 .oversampling_num = ARRAY_SIZE(ad7616_oversampling_avail),389 .os_req_reset = true,390 .init_delay_ms = 15,391 },392};393 394static int ad7606_request_gpios(struct ad7606_state *st)395{396 struct device *dev = st->dev;397 398 st->gpio_convst = devm_gpiod_get(dev, "adi,conversion-start",399 GPIOD_OUT_LOW);400 if (IS_ERR(st->gpio_convst))401 return PTR_ERR(st->gpio_convst);402 403 st->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);404 if (IS_ERR(st->gpio_reset))405 return PTR_ERR(st->gpio_reset);406 407 st->gpio_range = devm_gpiod_get_optional(dev, "adi,range",408 GPIOD_OUT_LOW);409 if (IS_ERR(st->gpio_range))410 return PTR_ERR(st->gpio_range);411 412 st->gpio_standby = devm_gpiod_get_optional(dev, "standby",413 GPIOD_OUT_LOW);414 if (IS_ERR(st->gpio_standby))415 return PTR_ERR(st->gpio_standby);416 417 st->gpio_frstdata = devm_gpiod_get_optional(dev, "adi,first-data",418 GPIOD_IN);419 if (IS_ERR(st->gpio_frstdata))420 return PTR_ERR(st->gpio_frstdata);421 422 if (!st->chip_info->oversampling_num)423 return 0;424 425 st->gpio_os = devm_gpiod_get_array_optional(dev,426 "adi,oversampling-ratio",427 GPIOD_OUT_LOW);428 return PTR_ERR_OR_ZERO(st->gpio_os);429}430 431/*432 * The BUSY signal indicates when conversions are in progress, so when a rising433 * edge of CONVST is applied, BUSY goes logic high and transitions low at the434 * end of the entire conversion process. The falling edge of the BUSY signal435 * triggers this interrupt.436 */437static irqreturn_t ad7606_interrupt(int irq, void *dev_id)438{439 struct iio_dev *indio_dev = dev_id;440 struct ad7606_state *st = iio_priv(indio_dev);441 442 if (iio_buffer_enabled(indio_dev)) {443 gpiod_set_value(st->gpio_convst, 0);444 iio_trigger_poll_nested(st->trig);445 } else {446 complete(&st->completion);447 }448 449 return IRQ_HANDLED;450};451 452static int ad7606_validate_trigger(struct iio_dev *indio_dev,453 struct iio_trigger *trig)454{455 struct ad7606_state *st = iio_priv(indio_dev);456 457 if (st->trig != trig)458 return -EINVAL;459 460 return 0;461}462 463static int ad7606_buffer_postenable(struct iio_dev *indio_dev)464{465 struct ad7606_state *st = iio_priv(indio_dev);466 467 gpiod_set_value(st->gpio_convst, 1);468 469 return 0;470}471 472static int ad7606_buffer_predisable(struct iio_dev *indio_dev)473{474 struct ad7606_state *st = iio_priv(indio_dev);475 476 gpiod_set_value(st->gpio_convst, 0);477 478 return 0;479}480 481static const struct iio_buffer_setup_ops ad7606_buffer_ops = {482 .postenable = &ad7606_buffer_postenable,483 .predisable = &ad7606_buffer_predisable,484};485 486static const struct iio_info ad7606_info_no_os_or_range = {487 .read_raw = &ad7606_read_raw,488 .validate_trigger = &ad7606_validate_trigger,489};490 491static const struct iio_info ad7606_info_os_and_range = {492 .read_raw = &ad7606_read_raw,493 .write_raw = &ad7606_write_raw,494 .attrs = &ad7606_attribute_group_os_and_range,495 .validate_trigger = &ad7606_validate_trigger,496};497 498static const struct iio_info ad7606_info_os_range_and_debug = {499 .read_raw = &ad7606_read_raw,500 .write_raw = &ad7606_write_raw,501 .debugfs_reg_access = &ad7606_reg_access,502 .attrs = &ad7606_attribute_group_os_and_range,503 .validate_trigger = &ad7606_validate_trigger,504};505 506static const struct iio_info ad7606_info_os = {507 .read_raw = &ad7606_read_raw,508 .write_raw = &ad7606_write_raw,509 .attrs = &ad7606_attribute_group_os,510 .validate_trigger = &ad7606_validate_trigger,511};512 513static const struct iio_info ad7606_info_range = {514 .read_raw = &ad7606_read_raw,515 .write_raw = &ad7606_write_raw,516 .attrs = &ad7606_attribute_group_range,517 .validate_trigger = &ad7606_validate_trigger,518};519 520static const struct iio_trigger_ops ad7606_trigger_ops = {521 .validate_device = iio_trigger_validate_own_device,522};523 524int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,525 const char *name, unsigned int id,526 const struct ad7606_bus_ops *bops)527{528 struct ad7606_state *st;529 int ret;530 struct iio_dev *indio_dev;531 532 indio_dev = devm_iio_device_alloc(dev, sizeof(*st));533 if (!indio_dev)534 return -ENOMEM;535 536 st = iio_priv(indio_dev);537 dev_set_drvdata(dev, indio_dev);538 539 st->dev = dev;540 mutex_init(&st->lock);541 st->bops = bops;542 st->base_address = base_address;543 /* tied to logic low, analog input range is +/- 5V */544 st->range[0] = 0;545 st->oversampling = 1;546 st->scale_avail = ad7606_scale_avail;547 st->num_scales = ARRAY_SIZE(ad7606_scale_avail);548 549 ret = devm_regulator_get_enable(dev, "avcc");550 if (ret)551 return dev_err_probe(dev, ret,552 "Failed to enable specified AVcc supply\n");553 554 st->chip_info = &ad7606_chip_info_tbl[id];555 556 if (st->chip_info->oversampling_num) {557 st->oversampling_avail = st->chip_info->oversampling_avail;558 st->num_os_ratios = st->chip_info->oversampling_num;559 }560 561 ret = ad7606_request_gpios(st);562 if (ret)563 return ret;564 565 if (st->gpio_os) {566 if (st->gpio_range)567 indio_dev->info = &ad7606_info_os_and_range;568 else569 indio_dev->info = &ad7606_info_os;570 } else {571 if (st->gpio_range)572 indio_dev->info = &ad7606_info_range;573 else574 indio_dev->info = &ad7606_info_no_os_or_range;575 }576 indio_dev->modes = INDIO_DIRECT_MODE;577 indio_dev->name = name;578 indio_dev->channels = st->chip_info->channels;579 indio_dev->num_channels = st->chip_info->num_channels;580 581 init_completion(&st->completion);582 583 ret = ad7606_reset(st);584 if (ret)585 dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");586 587 /* AD7616 requires al least 15ms to reconfigure after a reset */588 if (st->chip_info->init_delay_ms) {589 if (msleep_interruptible(st->chip_info->init_delay_ms))590 return -ERESTARTSYS;591 }592 593 st->write_scale = ad7606_write_scale_hw;594 st->write_os = ad7606_write_os_hw;595 596 if (st->bops->sw_mode_config)597 st->sw_mode_en = device_property_present(st->dev,598 "adi,sw-mode");599 600 if (st->sw_mode_en) {601 /* Scale of 0.076293 is only available in sw mode */602 st->scale_avail = ad7616_sw_scale_avail;603 st->num_scales = ARRAY_SIZE(ad7616_sw_scale_avail);604 605 /* After reset, in software mode, ±10 V is set by default */606 memset32(st->range, 2, ARRAY_SIZE(st->range));607 indio_dev->info = &ad7606_info_os_range_and_debug;608 609 ret = st->bops->sw_mode_config(indio_dev);610 if (ret < 0)611 return ret;612 }613 614 st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",615 indio_dev->name,616 iio_device_id(indio_dev));617 if (!st->trig)618 return -ENOMEM;619 620 st->trig->ops = &ad7606_trigger_ops;621 iio_trigger_set_drvdata(st->trig, indio_dev);622 ret = devm_iio_trigger_register(dev, st->trig);623 if (ret)624 return ret;625 626 indio_dev->trig = iio_trigger_get(st->trig);627 628 ret = devm_request_threaded_irq(dev, irq,629 NULL,630 &ad7606_interrupt,631 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,632 name, indio_dev);633 if (ret)634 return ret;635 636 ret = devm_iio_triggered_buffer_setup(dev, indio_dev,637 &iio_pollfunc_store_time,638 &ad7606_trigger_handler,639 &ad7606_buffer_ops);640 if (ret)641 return ret;642 643 return devm_iio_device_register(dev, indio_dev);644}645EXPORT_SYMBOL_NS_GPL(ad7606_probe, IIO_AD7606);646 647#ifdef CONFIG_PM_SLEEP648 649static int ad7606_suspend(struct device *dev)650{651 struct iio_dev *indio_dev = dev_get_drvdata(dev);652 struct ad7606_state *st = iio_priv(indio_dev);653 654 if (st->gpio_standby) {655 gpiod_set_value(st->gpio_range, 1);656 gpiod_set_value(st->gpio_standby, 1);657 }658 659 return 0;660}661 662static int ad7606_resume(struct device *dev)663{664 struct iio_dev *indio_dev = dev_get_drvdata(dev);665 struct ad7606_state *st = iio_priv(indio_dev);666 667 if (st->gpio_standby) {668 gpiod_set_value(st->gpio_range, st->range[0]);669 gpiod_set_value(st->gpio_standby, 1);670 ad7606_reset(st);671 }672 673 return 0;674}675 676SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);677EXPORT_SYMBOL_NS_GPL(ad7606_pm_ops, IIO_AD7606);678 679#endif680 681MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");682MODULE_DESCRIPTION("Analog Devices AD7606 ADC");683MODULE_LICENSE("GPL v2");684