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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Analog devices AD5360, AD5361, AD5362, AD5363, AD5370, AD5371, AD53734 * multi-channel Digital to Analog Converters driver5 *6 * Copyright 2011 Analog Devices Inc.7 */8 9#include <linux/device.h>10#include <linux/err.h>11#include <linux/module.h>12#include <linux/kernel.h>13#include <linux/spi/spi.h>14#include <linux/slab.h>15#include <linux/sysfs.h>16#include <linux/regulator/consumer.h>17 18#include <linux/iio/iio.h>19#include <linux/iio/sysfs.h>20 21#define AD5360_CMD(x)				((x) << 22)22#define AD5360_ADDR(x)				((x) << 16)23 24#define AD5360_READBACK_TYPE(x)			((x) << 13)25#define AD5360_READBACK_ADDR(x)			((x) << 7)26 27#define AD5360_CHAN_ADDR(chan)			((chan) + 0x8)28 29#define AD5360_CMD_WRITE_DATA			0x330#define AD5360_CMD_WRITE_OFFSET			0x231#define AD5360_CMD_WRITE_GAIN			0x132#define AD5360_CMD_SPECIAL_FUNCTION		0x033 34/* Special function register addresses */35#define AD5360_REG_SF_NOP			0x036#define AD5360_REG_SF_CTRL			0x137#define AD5360_REG_SF_OFS(x)			(0x2 + (x))38#define AD5360_REG_SF_READBACK			0x539 40#define AD5360_SF_CTRL_PWR_DOWN			BIT(0)41 42#define AD5360_READBACK_X1A			0x043#define AD5360_READBACK_X1B			0x144#define AD5360_READBACK_OFFSET			0x245#define AD5360_READBACK_GAIN			0x346#define AD5360_READBACK_SF			0x447 48 49/**50 * struct ad5360_chip_info - chip specific information51 * @channel_template:	channel specification template52 * @num_channels:	number of channels53 * @channels_per_group:	number of channels per group54 * @num_vrefs:		number of vref supplies for the chip55*/56 57struct ad5360_chip_info {58	struct iio_chan_spec	channel_template;59	unsigned int		num_channels;60	unsigned int		channels_per_group;61	unsigned int		num_vrefs;62};63 64/**65 * struct ad5360_state - driver instance specific data66 * @spi:		spi_device67 * @chip_info:		chip model specific constants, available modes etc68 * @vref_reg:		vref supply regulators69 * @ctrl:		control register cache70 * @lock:		lock to protect the data buffer during SPI ops71 * @data:		spi transfer buffers72 */73 74struct ad5360_state {75	struct spi_device		*spi;76	const struct ad5360_chip_info	*chip_info;77	struct regulator_bulk_data	vref_reg[3];78	unsigned int			ctrl;79	struct mutex			lock;80 81	/*82	 * DMA (thus cache coherency maintenance) may require the83	 * transfer buffers to live in their own cache lines.84	 */85	union {86		__be32 d32;87		u8 d8[4];88	} data[2] __aligned(IIO_DMA_MINALIGN);89};90 91enum ad5360_type {92	ID_AD5360,93	ID_AD5361,94	ID_AD5362,95	ID_AD5363,96	ID_AD5370,97	ID_AD5371,98	ID_AD5372,99	ID_AD5373,100};101 102#define AD5360_CHANNEL(bits) {					\103	.type = IIO_VOLTAGE,					\104	.indexed = 1,						\105	.output = 1,						\106	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\107		BIT(IIO_CHAN_INFO_SCALE) |				\108		BIT(IIO_CHAN_INFO_OFFSET) |				\109		BIT(IIO_CHAN_INFO_CALIBSCALE) |			\110		BIT(IIO_CHAN_INFO_CALIBBIAS),			\111	.scan_type = {						\112		.sign = 'u',					\113		.realbits = (bits),				\114		.storagebits = 16,				\115		.shift = 16 - (bits),				\116	},							\117}118 119static const struct ad5360_chip_info ad5360_chip_info_tbl[] = {120	[ID_AD5360] = {121		.channel_template = AD5360_CHANNEL(16),122		.num_channels = 16,123		.channels_per_group = 8,124		.num_vrefs = 2,125	},126	[ID_AD5361] = {127		.channel_template = AD5360_CHANNEL(14),128		.num_channels = 16,129		.channels_per_group = 8,130		.num_vrefs = 2,131	},132	[ID_AD5362] = {133		.channel_template = AD5360_CHANNEL(16),134		.num_channels = 8,135		.channels_per_group = 4,136		.num_vrefs = 2,137	},138	[ID_AD5363] = {139		.channel_template = AD5360_CHANNEL(14),140		.num_channels = 8,141		.channels_per_group = 4,142		.num_vrefs = 2,143	},144	[ID_AD5370] = {145		.channel_template = AD5360_CHANNEL(16),146		.num_channels = 40,147		.channels_per_group = 8,148		.num_vrefs = 2,149	},150	[ID_AD5371] = {151		.channel_template = AD5360_CHANNEL(14),152		.num_channels = 40,153		.channels_per_group = 8,154		.num_vrefs = 3,155	},156	[ID_AD5372] = {157		.channel_template = AD5360_CHANNEL(16),158		.num_channels = 32,159		.channels_per_group = 8,160		.num_vrefs = 2,161	},162	[ID_AD5373] = {163		.channel_template = AD5360_CHANNEL(14),164		.num_channels = 32,165		.channels_per_group = 8,166		.num_vrefs = 2,167	},168};169 170static unsigned int ad5360_get_channel_vref_index(struct ad5360_state *st,171	unsigned int channel)172{173	unsigned int i;174 175	/* The first groups have their own vref, while the remaining groups176	 * share the last vref */177	i = channel / st->chip_info->channels_per_group;178	if (i >= st->chip_info->num_vrefs)179		i = st->chip_info->num_vrefs - 1;180 181	return i;182}183 184static int ad5360_get_channel_vref(struct ad5360_state *st,185	unsigned int channel)186{187	unsigned int i = ad5360_get_channel_vref_index(st, channel);188 189	return regulator_get_voltage(st->vref_reg[i].consumer);190}191 192 193static int ad5360_write_unlocked(struct iio_dev *indio_dev,194	unsigned int cmd, unsigned int addr, unsigned int val,195	unsigned int shift)196{197	struct ad5360_state *st = iio_priv(indio_dev);198 199	val <<= shift;200	val |= AD5360_CMD(cmd) | AD5360_ADDR(addr);201	st->data[0].d32 = cpu_to_be32(val);202 203	return spi_write(st->spi, &st->data[0].d8[1], 3);204}205 206static int ad5360_write(struct iio_dev *indio_dev, unsigned int cmd,207	unsigned int addr, unsigned int val, unsigned int shift)208{209	int ret;210	struct ad5360_state *st = iio_priv(indio_dev);211 212	mutex_lock(&st->lock);213	ret = ad5360_write_unlocked(indio_dev, cmd, addr, val, shift);214	mutex_unlock(&st->lock);215 216	return ret;217}218 219static int ad5360_read(struct iio_dev *indio_dev, unsigned int type,220	unsigned int addr)221{222	struct ad5360_state *st = iio_priv(indio_dev);223	int ret;224	struct spi_transfer t[] = {225		{226			.tx_buf = &st->data[0].d8[1],227			.len = 3,228			.cs_change = 1,229		}, {230			.rx_buf = &st->data[1].d8[1],231			.len = 3,232		},233	};234 235	mutex_lock(&st->lock);236 237	st->data[0].d32 = cpu_to_be32(AD5360_CMD(AD5360_CMD_SPECIAL_FUNCTION) |238		AD5360_ADDR(AD5360_REG_SF_READBACK) |239		AD5360_READBACK_TYPE(type) |240		AD5360_READBACK_ADDR(addr));241 242	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));243	if (ret >= 0)244		ret = be32_to_cpu(st->data[1].d32) & 0xffff;245 246	mutex_unlock(&st->lock);247 248	return ret;249}250 251static ssize_t ad5360_read_dac_powerdown(struct device *dev,252					   struct device_attribute *attr,253					   char *buf)254{255	struct iio_dev *indio_dev = dev_to_iio_dev(dev);256	struct ad5360_state *st = iio_priv(indio_dev);257 258	return sysfs_emit(buf, "%d\n", (bool)(st->ctrl & AD5360_SF_CTRL_PWR_DOWN));259}260 261static int ad5360_update_ctrl(struct iio_dev *indio_dev, unsigned int set,262	unsigned int clr)263{264	struct ad5360_state *st = iio_priv(indio_dev);265	unsigned int ret;266 267	mutex_lock(&st->lock);268 269	st->ctrl |= set;270	st->ctrl &= ~clr;271 272	ret = ad5360_write_unlocked(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,273			AD5360_REG_SF_CTRL, st->ctrl, 0);274 275	mutex_unlock(&st->lock);276 277	return ret;278}279 280static ssize_t ad5360_write_dac_powerdown(struct device *dev,281	struct device_attribute *attr, const char *buf, size_t len)282{283	struct iio_dev *indio_dev = dev_to_iio_dev(dev);284	bool pwr_down;285	int ret;286 287	ret = kstrtobool(buf, &pwr_down);288	if (ret)289		return ret;290 291	if (pwr_down)292		ret = ad5360_update_ctrl(indio_dev, AD5360_SF_CTRL_PWR_DOWN, 0);293	else294		ret = ad5360_update_ctrl(indio_dev, 0, AD5360_SF_CTRL_PWR_DOWN);295 296	return ret ? ret : len;297}298 299static IIO_DEVICE_ATTR(out_voltage_powerdown,300			S_IRUGO | S_IWUSR,301			ad5360_read_dac_powerdown,302			ad5360_write_dac_powerdown, 0);303 304static struct attribute *ad5360_attributes[] = {305	&iio_dev_attr_out_voltage_powerdown.dev_attr.attr,306	NULL,307};308 309static const struct attribute_group ad5360_attribute_group = {310	.attrs = ad5360_attributes,311};312 313static int ad5360_write_raw(struct iio_dev *indio_dev,314			       struct iio_chan_spec const *chan,315			       int val,316			       int val2,317			       long mask)318{319	struct ad5360_state *st = iio_priv(indio_dev);320	int max_val = (1 << chan->scan_type.realbits);321	unsigned int ofs_index;322 323	switch (mask) {324	case IIO_CHAN_INFO_RAW:325		if (val >= max_val || val < 0)326			return -EINVAL;327 328		return ad5360_write(indio_dev, AD5360_CMD_WRITE_DATA,329				 chan->address, val, chan->scan_type.shift);330 331	case IIO_CHAN_INFO_CALIBBIAS:332		if (val >= max_val || val < 0)333			return -EINVAL;334 335		return ad5360_write(indio_dev, AD5360_CMD_WRITE_OFFSET,336				 chan->address, val, chan->scan_type.shift);337 338	case IIO_CHAN_INFO_CALIBSCALE:339		if (val >= max_val || val < 0)340			return -EINVAL;341 342		return ad5360_write(indio_dev, AD5360_CMD_WRITE_GAIN,343				 chan->address, val, chan->scan_type.shift);344 345	case IIO_CHAN_INFO_OFFSET:346		if (val <= -max_val || val > 0)347			return -EINVAL;348 349		val = -val;350 351		/* offset is supposed to have the same scale as raw, but it352		 * is always 14bits wide, so on a chip where the raw value has353		 * more bits, we need to shift offset. */354		val >>= (chan->scan_type.realbits - 14);355 356		/* There is one DAC offset register per vref. Changing one357		 * channels offset will also change the offset for all other358		 * channels which share the same vref supply. */359		ofs_index = ad5360_get_channel_vref_index(st, chan->channel);360		return ad5360_write(indio_dev, AD5360_CMD_SPECIAL_FUNCTION,361				 AD5360_REG_SF_OFS(ofs_index), val, 0);362	default:363		break;364	}365 366	return -EINVAL;367}368 369static int ad5360_read_raw(struct iio_dev *indio_dev,370			   struct iio_chan_spec const *chan,371			   int *val,372			   int *val2,373			   long m)374{375	struct ad5360_state *st = iio_priv(indio_dev);376	unsigned int ofs_index;377	int scale_uv;378	int ret;379 380	switch (m) {381	case IIO_CHAN_INFO_RAW:382		ret = ad5360_read(indio_dev, AD5360_READBACK_X1A,383			chan->address);384		if (ret < 0)385			return ret;386		*val = ret >> chan->scan_type.shift;387		return IIO_VAL_INT;388	case IIO_CHAN_INFO_SCALE:389		scale_uv = ad5360_get_channel_vref(st, chan->channel);390		if (scale_uv < 0)391			return scale_uv;392 393		/* vout = 4 * vref * dac_code */394		*val = scale_uv * 4 / 1000;395		*val2 = chan->scan_type.realbits;396		return IIO_VAL_FRACTIONAL_LOG2;397	case IIO_CHAN_INFO_CALIBBIAS:398		ret = ad5360_read(indio_dev, AD5360_READBACK_OFFSET,399			chan->address);400		if (ret < 0)401			return ret;402		*val = ret;403		return IIO_VAL_INT;404	case IIO_CHAN_INFO_CALIBSCALE:405		ret = ad5360_read(indio_dev, AD5360_READBACK_GAIN,406			chan->address);407		if (ret < 0)408			return ret;409		*val = ret;410		return IIO_VAL_INT;411	case IIO_CHAN_INFO_OFFSET:412		ofs_index = ad5360_get_channel_vref_index(st, chan->channel);413		ret = ad5360_read(indio_dev, AD5360_READBACK_SF,414			AD5360_REG_SF_OFS(ofs_index));415		if (ret < 0)416			return ret;417 418		ret <<= (chan->scan_type.realbits - 14);419		*val = -ret;420		return IIO_VAL_INT;421	}422 423	return -EINVAL;424}425 426static const struct iio_info ad5360_info = {427	.read_raw = ad5360_read_raw,428	.write_raw = ad5360_write_raw,429	.attrs = &ad5360_attribute_group,430};431 432static const char * const ad5360_vref_name[] = {433	 "vref0", "vref1", "vref2"434};435 436static int ad5360_alloc_channels(struct iio_dev *indio_dev)437{438	struct ad5360_state *st = iio_priv(indio_dev);439	struct iio_chan_spec *channels;440	unsigned int i;441 442	channels = kcalloc(st->chip_info->num_channels,443			   sizeof(struct iio_chan_spec), GFP_KERNEL);444 445	if (!channels)446		return -ENOMEM;447 448	for (i = 0; i < st->chip_info->num_channels; ++i) {449		channels[i] = st->chip_info->channel_template;450		channels[i].channel = i;451		channels[i].address = AD5360_CHAN_ADDR(i);452	}453 454	indio_dev->channels = channels;455 456	return 0;457}458 459static int ad5360_probe(struct spi_device *spi)460{461	enum ad5360_type type = spi_get_device_id(spi)->driver_data;462	struct iio_dev *indio_dev;463	struct ad5360_state *st;464	unsigned int i;465	int ret;466 467	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));468	if (indio_dev == NULL) {469		dev_err(&spi->dev, "Failed to allocate iio device\n");470		return  -ENOMEM;471	}472 473	st = iio_priv(indio_dev);474	spi_set_drvdata(spi, indio_dev);475 476	st->chip_info = &ad5360_chip_info_tbl[type];477	st->spi = spi;478 479	indio_dev->name = spi_get_device_id(spi)->name;480	indio_dev->info = &ad5360_info;481	indio_dev->modes = INDIO_DIRECT_MODE;482	indio_dev->num_channels = st->chip_info->num_channels;483 484	mutex_init(&st->lock);485 486	ret = ad5360_alloc_channels(indio_dev);487	if (ret) {488		dev_err(&spi->dev, "Failed to allocate channel spec: %d\n", ret);489		return ret;490	}491 492	for (i = 0; i < st->chip_info->num_vrefs; ++i)493		st->vref_reg[i].supply = ad5360_vref_name[i];494 495	ret = devm_regulator_bulk_get(&st->spi->dev, st->chip_info->num_vrefs,496		st->vref_reg);497	if (ret) {498		dev_err(&spi->dev, "Failed to request vref regulators: %d\n", ret);499		goto error_free_channels;500	}501 502	ret = regulator_bulk_enable(st->chip_info->num_vrefs, st->vref_reg);503	if (ret) {504		dev_err(&spi->dev, "Failed to enable vref regulators: %d\n", ret);505		goto error_free_channels;506	}507 508	ret = iio_device_register(indio_dev);509	if (ret) {510		dev_err(&spi->dev, "Failed to register iio device: %d\n", ret);511		goto error_disable_reg;512	}513 514	return 0;515 516error_disable_reg:517	regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);518error_free_channels:519	kfree(indio_dev->channels);520 521	return ret;522}523 524static void ad5360_remove(struct spi_device *spi)525{526	struct iio_dev *indio_dev = spi_get_drvdata(spi);527	struct ad5360_state *st = iio_priv(indio_dev);528 529	iio_device_unregister(indio_dev);530 531	kfree(indio_dev->channels);532 533	regulator_bulk_disable(st->chip_info->num_vrefs, st->vref_reg);534}535 536static const struct spi_device_id ad5360_ids[] = {537	{ "ad5360", ID_AD5360 },538	{ "ad5361", ID_AD5361 },539	{ "ad5362", ID_AD5362 },540	{ "ad5363", ID_AD5363 },541	{ "ad5370", ID_AD5370 },542	{ "ad5371", ID_AD5371 },543	{ "ad5372", ID_AD5372 },544	{ "ad5373", ID_AD5373 },545	{}546};547MODULE_DEVICE_TABLE(spi, ad5360_ids);548 549static struct spi_driver ad5360_driver = {550	.driver = {551		   .name = "ad5360",552	},553	.probe = ad5360_probe,554	.remove = ad5360_remove,555	.id_table = ad5360_ids,556};557module_spi_driver(ad5360_driver);558 559MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");560MODULE_DESCRIPTION("Analog Devices AD5360/61/62/63/70/71/72/73 DAC");561MODULE_LICENSE("GPL v2");562