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1// SPDX-License-Identifier: GPL-2.0+2/*3 * AD4000 SPI ADC driver4 *5 * Copyright 2024 Analog Devices Inc.6 */7#include <linux/bits.h>8#include <linux/bitfield.h>9#include <linux/byteorder/generic.h>10#include <linux/cleanup.h>11#include <linux/device.h>12#include <linux/err.h>13#include <linux/math.h>14#include <linux/module.h>15#include <linux/mod_devicetable.h>16#include <linux/gpio/consumer.h>17#include <linux/regulator/consumer.h>18#include <linux/spi/spi.h>19#include <linux/units.h>20#include <linux/util_macros.h>21#include <linux/iio/iio.h>22 23#include <linux/iio/buffer.h>24#include <linux/iio/triggered_buffer.h>25#include <linux/iio/trigger_consumer.h>26 27#define AD4000_READ_COMMAND	0x5428#define AD4000_WRITE_COMMAND	0x1429 30#define AD4000_CONFIG_REG_DEFAULT	0xE131 32/* AD4000 Configuration Register programmable bits */33#define AD4000_CFG_SPAN_COMP		BIT(3) /* Input span compression  */34#define AD4000_CFG_HIGHZ		BIT(2) /* High impedance mode  */35 36#define AD4000_SCALE_OPTIONS		237 38#define AD4000_TQUIET1_NS		19039#define AD4000_TQUIET2_NS		6040#define AD4000_TCONV_NS			32041 42#define __AD4000_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access)	\43{										\44	.type = IIO_VOLTAGE,							\45	.indexed = 1,								\46	.differential = 1,							\47	.channel = 0,								\48	.channel2 = 1,								\49	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |				\50			      BIT(IIO_CHAN_INFO_SCALE),				\51	.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\52	.scan_type = {								\53		.sign = _sign,							\54		.realbits = _real_bits,						\55		.storagebits = _storage_bits,					\56		.shift = _storage_bits - _real_bits,				\57		.endianness = IIO_BE,						\58	},									\59}60 61#define AD4000_DIFF_CHANNEL(_sign, _real_bits, _reg_access)			\62	__AD4000_DIFF_CHANNEL((_sign), (_real_bits),				\63				     ((_real_bits) > 16 ? 32 : 16), (_reg_access))64 65#define __AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _storage_bits, _reg_access)\66{										\67	.type = IIO_VOLTAGE,							\68	.indexed = 1,								\69	.channel = 0,								\70	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |				\71			      BIT(IIO_CHAN_INFO_SCALE) |			\72			      BIT(IIO_CHAN_INFO_OFFSET),			\73	.info_mask_separate_available = _reg_access ? BIT(IIO_CHAN_INFO_SCALE) : 0,\74	.scan_type = {								\75		.sign = _sign,							\76		.realbits = _real_bits,						\77		.storagebits = _storage_bits,					\78		.shift = _storage_bits - _real_bits,				\79		.endianness = IIO_BE,						\80	},									\81}82 83#define AD4000_PSEUDO_DIFF_CHANNEL(_sign, _real_bits, _reg_access)		\84	__AD4000_PSEUDO_DIFF_CHANNEL((_sign), (_real_bits),			\85				     ((_real_bits) > 16 ? 32 : 16), (_reg_access))86 87static const char * const ad4000_power_supplies[] = {88	"vdd", "vio"89};90 91enum ad4000_sdi {92	AD4000_SDI_MOSI,93	AD4000_SDI_VIO,94	AD4000_SDI_CS,95	AD4000_SDI_GND,96};97 98/* maps adi,sdi-pin property value to enum */99static const char * const ad4000_sdi_pin[] = {100	[AD4000_SDI_MOSI] = "sdi",101	[AD4000_SDI_VIO] = "high",102	[AD4000_SDI_CS] = "cs",103	[AD4000_SDI_GND] = "low",104};105 106/* Gains stored as fractions of 1000 so they can be expressed by integers. */107static const int ad4000_gains[] = {108	454, 909, 1000, 1900,109};110 111struct ad4000_chip_info {112	const char *dev_name;113	struct iio_chan_spec chan_spec;114	struct iio_chan_spec reg_access_chan_spec;115	bool has_hardware_gain;116};117 118static const struct ad4000_chip_info ad4000_chip_info = {119	.dev_name = "ad4000",120	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),121	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),122};123 124static const struct ad4000_chip_info ad4001_chip_info = {125	.dev_name = "ad4001",126	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),127	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),128};129 130static const struct ad4000_chip_info ad4002_chip_info = {131	.dev_name = "ad4002",132	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),133	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),134};135 136static const struct ad4000_chip_info ad4003_chip_info = {137	.dev_name = "ad4003",138	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),139	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),140};141 142static const struct ad4000_chip_info ad4004_chip_info = {143	.dev_name = "ad4004",144	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),145	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),146};147 148static const struct ad4000_chip_info ad4005_chip_info = {149	.dev_name = "ad4005",150	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),151	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),152};153 154static const struct ad4000_chip_info ad4006_chip_info = {155	.dev_name = "ad4006",156	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),157	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),158};159 160static const struct ad4000_chip_info ad4007_chip_info = {161	.dev_name = "ad4007",162	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),163	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),164};165 166static const struct ad4000_chip_info ad4008_chip_info = {167	.dev_name = "ad4008",168	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 0),169	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 16, 1),170};171 172static const struct ad4000_chip_info ad4010_chip_info = {173	.dev_name = "ad4010",174	.chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 0),175	.reg_access_chan_spec = AD4000_PSEUDO_DIFF_CHANNEL('u', 18, 1),176};177 178static const struct ad4000_chip_info ad4011_chip_info = {179	.dev_name = "ad4011",180	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),181	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),182};183 184static const struct ad4000_chip_info ad4020_chip_info = {185	.dev_name = "ad4020",186	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),187	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),188};189 190static const struct ad4000_chip_info ad4021_chip_info = {191	.dev_name = "ad4021",192	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),193	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),194};195 196static const struct ad4000_chip_info ad4022_chip_info = {197	.dev_name = "ad4022",198	.chan_spec = AD4000_DIFF_CHANNEL('s', 20, 0),199	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 20, 1),200};201 202static const struct ad4000_chip_info adaq4001_chip_info = {203	.dev_name = "adaq4001",204	.chan_spec = AD4000_DIFF_CHANNEL('s', 16, 0),205	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 16, 1),206	.has_hardware_gain = true,207};208 209static const struct ad4000_chip_info adaq4003_chip_info = {210	.dev_name = "adaq4003",211	.chan_spec = AD4000_DIFF_CHANNEL('s', 18, 0),212	.reg_access_chan_spec = AD4000_DIFF_CHANNEL('s', 18, 1),213	.has_hardware_gain = true,214};215 216struct ad4000_state {217	struct spi_device *spi;218	struct gpio_desc *cnv_gpio;219	struct spi_transfer xfers[2];220	struct spi_message msg;221	struct mutex lock; /* Protect read modify write cycle */222	int vref_mv;223	enum ad4000_sdi sdi_pin;224	bool span_comp;225	u16 gain_milli;226	int scale_tbl[AD4000_SCALE_OPTIONS][2];227 228	/*229	 * DMA (thus cache coherency maintenance) requires the transfer buffers230	 * to live in their own cache lines.231	 */232	struct {233		union {234			__be16 sample_buf16;235			__be32 sample_buf32;236		} data;237		s64 timestamp __aligned(8);238	} scan __aligned(IIO_DMA_MINALIGN);239	u8 tx_buf[2];240	u8 rx_buf[2];241};242 243static void ad4000_fill_scale_tbl(struct ad4000_state *st,244				  struct iio_chan_spec const *chan)245{246	int val, tmp0, tmp1;247	int scale_bits;248	u64 tmp2;249 250	/*251	 * ADCs that output two's complement code have one less bit to express252	 * voltage magnitude.253	 */254	if (chan->scan_type.sign == 's')255		scale_bits = chan->scan_type.realbits - 1;256	else257		scale_bits = chan->scan_type.realbits;258 259	/*260	 * The gain is stored as a fraction of 1000 and, as we need to261	 * divide vref_mv by the gain, we invert the gain/1000 fraction.262	 * Also multiply by an extra MILLI to preserve precision.263	 * Thus, we have MILLI * MILLI equals MICRO as fraction numerator.264	 */265	val = mult_frac(st->vref_mv, MICRO, st->gain_milli);266 267	/* Would multiply by NANO here but we multiplied by extra MILLI */268	tmp2 = shift_right((u64)val * MICRO, scale_bits);269	tmp0 = div_s64_rem(tmp2, NANO, &tmp1);270 271	/* Store scale for when span compression is disabled */272	st->scale_tbl[0][0] = tmp0; /* Integer part */273	st->scale_tbl[0][1] = abs(tmp1); /* Fractional part */274 275	/* Store scale for when span compression is enabled */276	st->scale_tbl[1][0] = tmp0;277 278	/* The integer part is always zero so don't bother to divide it. */279	if (chan->differential)280		st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 4, 5);281	else282		st->scale_tbl[1][1] = DIV_ROUND_CLOSEST(abs(tmp1) * 9, 10);283}284 285static int ad4000_write_reg(struct ad4000_state *st, uint8_t val)286{287	st->tx_buf[0] = AD4000_WRITE_COMMAND;288	st->tx_buf[1] = val;289	return spi_write(st->spi, st->tx_buf, ARRAY_SIZE(st->tx_buf));290}291 292static int ad4000_read_reg(struct ad4000_state *st, unsigned int *val)293{294	struct spi_transfer t = {295		.tx_buf = st->tx_buf,296		.rx_buf = st->rx_buf,297		.len = 2,298	};299	int ret;300 301	st->tx_buf[0] = AD4000_READ_COMMAND;302	ret = spi_sync_transfer(st->spi, &t, 1);303	if (ret < 0)304		return ret;305 306	*val = st->rx_buf[1];307	return ret;308}309 310static int ad4000_convert_and_acquire(struct ad4000_state *st)311{312	int ret;313 314	/*315	 * In 4-wire mode, the CNV line is held high for the entire conversion316	 * and acquisition process. In other modes, the CNV GPIO is optional317	 * and, if provided, replaces controller CS. If CNV GPIO is not defined318	 * gpiod_set_value_cansleep() has no effect.319	 */320	gpiod_set_value_cansleep(st->cnv_gpio, 1);321	ret = spi_sync(st->spi, &st->msg);322	gpiod_set_value_cansleep(st->cnv_gpio, 0);323 324	return ret;325}326 327static int ad4000_single_conversion(struct iio_dev *indio_dev,328				    const struct iio_chan_spec *chan, int *val)329{330	struct ad4000_state *st = iio_priv(indio_dev);331	u32 sample;332	int ret;333 334	ret = ad4000_convert_and_acquire(st);335	if (ret < 0)336		return ret;337 338	if (chan->scan_type.storagebits > 16)339		sample = be32_to_cpu(st->scan.data.sample_buf32);340	else341		sample = be16_to_cpu(st->scan.data.sample_buf16);342 343	sample >>= chan->scan_type.shift;344 345	if (chan->scan_type.sign == 's')346		*val = sign_extend32(sample, chan->scan_type.realbits - 1);347 348	return IIO_VAL_INT;349}350 351static int ad4000_read_raw(struct iio_dev *indio_dev,352			   struct iio_chan_spec const *chan, int *val,353			   int *val2, long info)354{355	struct ad4000_state *st = iio_priv(indio_dev);356 357	switch (info) {358	case IIO_CHAN_INFO_RAW:359		iio_device_claim_direct_scoped(return -EBUSY, indio_dev)360			return ad4000_single_conversion(indio_dev, chan, val);361		unreachable();362	case IIO_CHAN_INFO_SCALE:363		*val = st->scale_tbl[st->span_comp][0];364		*val2 = st->scale_tbl[st->span_comp][1];365		return IIO_VAL_INT_PLUS_NANO;366	case IIO_CHAN_INFO_OFFSET:367		*val = 0;368		if (st->span_comp)369			*val = mult_frac(st->vref_mv, 1, 10);370 371		return IIO_VAL_INT;372	default:373		return -EINVAL;374	}375}376 377static int ad4000_read_avail(struct iio_dev *indio_dev,378			     struct iio_chan_spec const *chan,379			     const int **vals, int *type, int *length,380			     long info)381{382	struct ad4000_state *st = iio_priv(indio_dev);383 384	switch (info) {385	case IIO_CHAN_INFO_SCALE:386		*vals = (int *)st->scale_tbl;387		*length = AD4000_SCALE_OPTIONS * 2;388		*type = IIO_VAL_INT_PLUS_NANO;389		return IIO_AVAIL_LIST;390	default:391		return -EINVAL;392	}393}394 395static int ad4000_write_raw_get_fmt(struct iio_dev *indio_dev,396				    struct iio_chan_spec const *chan, long mask)397{398	switch (mask) {399	case IIO_CHAN_INFO_SCALE:400		return IIO_VAL_INT_PLUS_NANO;401	default:402		return IIO_VAL_INT_PLUS_MICRO;403	}404}405 406static int ad4000_write_raw(struct iio_dev *indio_dev,407			    struct iio_chan_spec const *chan, int val, int val2,408			    long mask)409{410	struct ad4000_state *st = iio_priv(indio_dev);411	unsigned int reg_val;412	bool span_comp_en;413	int ret;414 415	switch (mask) {416	case IIO_CHAN_INFO_SCALE:417		iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {418			guard(mutex)(&st->lock);419 420			ret = ad4000_read_reg(st, &reg_val);421			if (ret < 0)422				return ret;423 424			span_comp_en = val2 == st->scale_tbl[1][1];425			reg_val &= ~AD4000_CFG_SPAN_COMP;426			reg_val |= FIELD_PREP(AD4000_CFG_SPAN_COMP, span_comp_en);427 428			ret = ad4000_write_reg(st, reg_val);429			if (ret < 0)430				return ret;431 432			st->span_comp = span_comp_en;433			return 0;434		}435		unreachable();436	default:437		return -EINVAL;438	}439}440 441static irqreturn_t ad4000_trigger_handler(int irq, void *p)442{443	struct iio_poll_func *pf = p;444	struct iio_dev *indio_dev = pf->indio_dev;445	struct ad4000_state *st = iio_priv(indio_dev);446	int ret;447 448	ret = ad4000_convert_and_acquire(st);449	if (ret < 0)450		goto err_out;451 452	iio_push_to_buffers_with_timestamp(indio_dev, &st->scan, pf->timestamp);453 454err_out:455	iio_trigger_notify_done(indio_dev->trig);456	return IRQ_HANDLED;457}458 459static const struct iio_info ad4000_reg_access_info = {460	.read_raw = &ad4000_read_raw,461	.read_avail = &ad4000_read_avail,462	.write_raw = &ad4000_write_raw,463	.write_raw_get_fmt = &ad4000_write_raw_get_fmt,464};465 466static const struct iio_info ad4000_info = {467	.read_raw = &ad4000_read_raw,468};469 470/*471 * This executes a data sample transfer for when the device connections are472 * in "3-wire" mode, selected when the adi,sdi-pin device tree property is473 * absent or set to "high". In this connection mode, the ADC SDI pin is474 * connected to MOSI or to VIO and ADC CNV pin is connected either to a SPI475 * controller CS or to a GPIO.476 * AD4000 series of devices initiate conversions on the rising edge of CNV pin.477 *478 * If the CNV pin is connected to an SPI controller CS line (which is by default479 * active low), the ADC readings would have a latency (delay) of one read.480 * Moreover, since we also do ADC sampling for filling the buffer on triggered481 * buffer mode, the timestamps of buffer readings would be disarranged.482 * To prevent the read latency and reduce the time discrepancy between the483 * sample read request and the time of actual sampling by the ADC, do a484 * preparatory transfer to pulse the CS/CNV line.485 */486static int ad4000_prepare_3wire_mode_message(struct ad4000_state *st,487					     const struct iio_chan_spec *chan)488{489	unsigned int cnv_pulse_time = AD4000_TCONV_NS;490	struct spi_transfer *xfers = st->xfers;491 492	xfers[0].cs_change = 1;493	xfers[0].cs_change_delay.value = cnv_pulse_time;494	xfers[0].cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;495 496	xfers[1].rx_buf = &st->scan.data;497	xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);498	xfers[1].delay.value = AD4000_TQUIET2_NS;499	xfers[1].delay.unit = SPI_DELAY_UNIT_NSECS;500 501	spi_message_init_with_transfers(&st->msg, st->xfers, 2);502 503	return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);504}505 506/*507 * This executes a data sample transfer for when the device connections are508 * in "4-wire" mode, selected when the adi,sdi-pin device tree property is509 * set to "cs". In this connection mode, the controller CS pin is connected to510 * ADC SDI pin and a GPIO is connected to ADC CNV pin.511 * The GPIO connected to ADC CNV pin is set outside of the SPI transfer.512 */513static int ad4000_prepare_4wire_mode_message(struct ad4000_state *st,514					     const struct iio_chan_spec *chan)515{516	unsigned int cnv_to_sdi_time = AD4000_TCONV_NS;517	struct spi_transfer *xfers = st->xfers;518 519	/*520	 * Dummy transfer to cause enough delay between CNV going high and SDI521	 * going low.522	 */523	xfers[0].cs_off = 1;524	xfers[0].delay.value = cnv_to_sdi_time;525	xfers[0].delay.unit = SPI_DELAY_UNIT_NSECS;526 527	xfers[1].rx_buf = &st->scan.data;528	xfers[1].len = BITS_TO_BYTES(chan->scan_type.storagebits);529 530	spi_message_init_with_transfers(&st->msg, st->xfers, 2);531 532	return devm_spi_optimize_message(&st->spi->dev, st->spi, &st->msg);533}534 535static int ad4000_config(struct ad4000_state *st)536{537	unsigned int reg_val = AD4000_CONFIG_REG_DEFAULT;538 539	if (device_property_present(&st->spi->dev, "adi,high-z-input"))540		reg_val |= FIELD_PREP(AD4000_CFG_HIGHZ, 1);541 542	return ad4000_write_reg(st, reg_val);543}544 545static int ad4000_probe(struct spi_device *spi)546{547	const struct ad4000_chip_info *chip;548	struct device *dev = &spi->dev;549	struct iio_dev *indio_dev;550	struct ad4000_state *st;551	int gain_idx, ret;552 553	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));554	if (!indio_dev)555		return -ENOMEM;556 557	chip = spi_get_device_match_data(spi);558	if (!chip)559		return -EINVAL;560 561	st = iio_priv(indio_dev);562	st->spi = spi;563 564	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ad4000_power_supplies),565					     ad4000_power_supplies);566	if (ret)567		return dev_err_probe(dev, ret, "Failed to enable power supplies\n");568 569	ret = devm_regulator_get_enable_read_voltage(dev, "ref");570	if (ret < 0)571		return dev_err_probe(dev, ret,572				     "Failed to get ref regulator reference\n");573	st->vref_mv = ret / 1000;574 575	st->cnv_gpio = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_HIGH);576	if (IS_ERR(st->cnv_gpio))577		return dev_err_probe(dev, PTR_ERR(st->cnv_gpio),578				     "Failed to get CNV GPIO");579 580	ret = device_property_match_property_string(dev, "adi,sdi-pin",581						    ad4000_sdi_pin,582						    ARRAY_SIZE(ad4000_sdi_pin));583	if (ret < 0 && ret != -EINVAL)584		return dev_err_probe(dev, ret,585				     "getting adi,sdi-pin property failed\n");586 587	/* Default to usual SPI connections if pin properties are not present */588	st->sdi_pin = ret == -EINVAL ? AD4000_SDI_MOSI : ret;589	switch (st->sdi_pin) {590	case AD4000_SDI_MOSI:591		indio_dev->info = &ad4000_reg_access_info;592		indio_dev->channels = &chip->reg_access_chan_spec;593 594		/*595		 * In "3-wire mode", the ADC SDI line must be kept high when596		 * data is not being clocked out of the controller.597		 * Request the SPI controller to make MOSI idle high.598		 */599		spi->mode |= SPI_MOSI_IDLE_HIGH;600		ret = spi_setup(spi);601		if (ret < 0)602			return ret;603 604		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);605		if (ret)606			return ret;607 608		ret = ad4000_config(st);609		if (ret < 0)610			return dev_err_probe(dev, ret, "Failed to config device\n");611 612		break;613	case AD4000_SDI_VIO:614		indio_dev->info = &ad4000_info;615		indio_dev->channels = &chip->chan_spec;616		ret = ad4000_prepare_3wire_mode_message(st, indio_dev->channels);617		if (ret)618			return ret;619 620		break;621	case AD4000_SDI_CS:622		indio_dev->info = &ad4000_info;623		indio_dev->channels = &chip->chan_spec;624		ret = ad4000_prepare_4wire_mode_message(st, indio_dev->channels);625		if (ret)626			return ret;627 628		break;629	case AD4000_SDI_GND:630		return dev_err_probe(dev, -EPROTONOSUPPORT,631				     "Unsupported connection mode\n");632 633	default:634		return dev_err_probe(dev, -EINVAL, "Unrecognized connection mode\n");635	}636 637	indio_dev->name = chip->dev_name;638	indio_dev->num_channels = 1;639 640	devm_mutex_init(dev, &st->lock);641 642	st->gain_milli = 1000;643	if (chip->has_hardware_gain) {644		ret = device_property_read_u16(dev, "adi,gain-milli",645					       &st->gain_milli);646		if (!ret) {647			/* Match gain value from dt to one of supported gains */648			gain_idx = find_closest(st->gain_milli, ad4000_gains,649						ARRAY_SIZE(ad4000_gains));650			st->gain_milli = ad4000_gains[gain_idx];651		} else {652			return dev_err_probe(dev, ret,653					     "Failed to read gain property\n");654		}655	}656 657	ad4000_fill_scale_tbl(st, indio_dev->channels);658 659	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,660					      &iio_pollfunc_store_time,661					      &ad4000_trigger_handler, NULL);662	if (ret)663		return ret;664 665	return devm_iio_device_register(dev, indio_dev);666}667 668static const struct spi_device_id ad4000_id[] = {669	{ "ad4000", (kernel_ulong_t)&ad4000_chip_info },670	{ "ad4001", (kernel_ulong_t)&ad4001_chip_info },671	{ "ad4002", (kernel_ulong_t)&ad4002_chip_info },672	{ "ad4003", (kernel_ulong_t)&ad4003_chip_info },673	{ "ad4004", (kernel_ulong_t)&ad4004_chip_info },674	{ "ad4005", (kernel_ulong_t)&ad4005_chip_info },675	{ "ad4006", (kernel_ulong_t)&ad4006_chip_info },676	{ "ad4007", (kernel_ulong_t)&ad4007_chip_info },677	{ "ad4008", (kernel_ulong_t)&ad4008_chip_info },678	{ "ad4010", (kernel_ulong_t)&ad4010_chip_info },679	{ "ad4011", (kernel_ulong_t)&ad4011_chip_info },680	{ "ad4020", (kernel_ulong_t)&ad4020_chip_info },681	{ "ad4021", (kernel_ulong_t)&ad4021_chip_info },682	{ "ad4022", (kernel_ulong_t)&ad4022_chip_info },683	{ "adaq4001", (kernel_ulong_t)&adaq4001_chip_info },684	{ "adaq4003", (kernel_ulong_t)&adaq4003_chip_info },685	{ }686};687MODULE_DEVICE_TABLE(spi, ad4000_id);688 689static const struct of_device_id ad4000_of_match[] = {690	{ .compatible = "adi,ad4000", .data = &ad4000_chip_info },691	{ .compatible = "adi,ad4001", .data = &ad4001_chip_info },692	{ .compatible = "adi,ad4002", .data = &ad4002_chip_info },693	{ .compatible = "adi,ad4003", .data = &ad4003_chip_info },694	{ .compatible = "adi,ad4004", .data = &ad4004_chip_info },695	{ .compatible = "adi,ad4005", .data = &ad4005_chip_info },696	{ .compatible = "adi,ad4006", .data = &ad4006_chip_info },697	{ .compatible = "adi,ad4007", .data = &ad4007_chip_info },698	{ .compatible = "adi,ad4008", .data = &ad4008_chip_info },699	{ .compatible = "adi,ad4010", .data = &ad4010_chip_info },700	{ .compatible = "adi,ad4011", .data = &ad4011_chip_info },701	{ .compatible = "adi,ad4020", .data = &ad4020_chip_info },702	{ .compatible = "adi,ad4021", .data = &ad4021_chip_info },703	{ .compatible = "adi,ad4022", .data = &ad4022_chip_info },704	{ .compatible = "adi,adaq4001", .data = &adaq4001_chip_info },705	{ .compatible = "adi,adaq4003", .data = &adaq4003_chip_info },706	{ }707};708MODULE_DEVICE_TABLE(of, ad4000_of_match);709 710static struct spi_driver ad4000_driver = {711	.driver = {712		.name   = "ad4000",713		.of_match_table = ad4000_of_match,714	},715	.probe          = ad4000_probe,716	.id_table       = ad4000_id,717};718module_spi_driver(ad4000_driver);719 720MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@analog.com>");721MODULE_DESCRIPTION("Analog Devices AD4000 ADC driver");722MODULE_LICENSE("GPL");723