357 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AD5415, AD5426, AD5429, AD5432, AD5439, AD5443, AD5449 Digital to Analog4 * Converter driver.5 *6 * Copyright 2012 Analog Devices Inc.7 * Author: Lars-Peter Clausen <lars@metafoo.de>8 */9 10#include <linux/device.h>11#include <linux/err.h>12#include <linux/module.h>13#include <linux/kernel.h>14#include <linux/spi/spi.h>15#include <linux/slab.h>16#include <linux/sysfs.h>17#include <linux/regulator/consumer.h>18#include <linux/unaligned.h>19 20#include <linux/iio/iio.h>21#include <linux/iio/sysfs.h>22 23#define AD5449_MAX_CHANNELS 224#define AD5449_MAX_VREFS 225 26#define AD5449_CMD_NOOP 0x027#define AD5449_CMD_LOAD_AND_UPDATE(x) (0x1 + (x) * 3)28#define AD5449_CMD_READ(x) (0x2 + (x) * 3)29#define AD5449_CMD_LOAD(x) (0x3 + (x) * 3)30#define AD5449_CMD_CTRL 1331 32#define AD5449_CTRL_SDO_OFFSET 1033#define AD5449_CTRL_DAISY_CHAIN BIT(9)34#define AD5449_CTRL_HCLR_TO_MIDSCALE BIT(8)35#define AD5449_CTRL_SAMPLE_RISING BIT(7)36 37/**38 * struct ad5449_chip_info - chip specific information39 * @channels: Channel specification40 * @num_channels: Number of channels41 * @has_ctrl: Chip has a control register42 */43struct ad5449_chip_info {44 const struct iio_chan_spec *channels;45 unsigned int num_channels;46 bool has_ctrl;47};48 49/**50 * struct ad5449 - driver instance specific data51 * @spi: the SPI device for this driver instance52 * @chip_info: chip model specific constants, available modes etc53 * @vref_reg: vref supply regulators54 * @has_sdo: whether the SDO line is connected55 * @dac_cache: Cache for the DAC values56 * @data: spi transfer buffers57 * @lock: lock to protect the data buffer during SPI ops58 */59struct ad5449 {60 struct spi_device *spi;61 const struct ad5449_chip_info *chip_info;62 struct regulator_bulk_data vref_reg[AD5449_MAX_VREFS];63 struct mutex lock;64 65 bool has_sdo;66 uint16_t dac_cache[AD5449_MAX_CHANNELS];67 68 /*69 * DMA (thus cache coherency maintenance) may require the70 * transfer buffers to live in their own cache lines.71 */72 __be16 data[2] __aligned(IIO_DMA_MINALIGN);73};74 75enum ad5449_type {76 ID_AD5426,77 ID_AD5429,78 ID_AD5432,79 ID_AD5439,80 ID_AD5443,81 ID_AD5449,82};83 84static int ad5449_write(struct iio_dev *indio_dev, unsigned int addr,85 unsigned int val)86{87 struct ad5449 *st = iio_priv(indio_dev);88 int ret;89 90 mutex_lock(&st->lock);91 st->data[0] = cpu_to_be16((addr << 12) | val);92 ret = spi_write(st->spi, st->data, 2);93 mutex_unlock(&st->lock);94 95 return ret;96}97 98static int ad5449_read(struct iio_dev *indio_dev, unsigned int addr,99 unsigned int *val)100{101 struct ad5449 *st = iio_priv(indio_dev);102 int ret;103 struct spi_transfer t[] = {104 {105 .tx_buf = &st->data[0],106 .len = 2,107 .cs_change = 1,108 }, {109 .tx_buf = &st->data[1],110 .rx_buf = &st->data[1],111 .len = 2,112 },113 };114 115 mutex_lock(&st->lock);116 st->data[0] = cpu_to_be16(addr << 12);117 st->data[1] = cpu_to_be16(AD5449_CMD_NOOP);118 119 ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));120 if (ret < 0)121 goto out_unlock;122 123 *val = be16_to_cpu(st->data[1]);124 125out_unlock:126 mutex_unlock(&st->lock);127 return ret;128}129 130static int ad5449_read_raw(struct iio_dev *indio_dev,131 struct iio_chan_spec const *chan, int *val, int *val2, long info)132{133 struct ad5449 *st = iio_priv(indio_dev);134 struct regulator_bulk_data *reg;135 int scale_uv;136 int ret;137 138 switch (info) {139 case IIO_CHAN_INFO_RAW:140 if (st->has_sdo) {141 ret = ad5449_read(indio_dev,142 AD5449_CMD_READ(chan->address), val);143 if (ret)144 return ret;145 *val &= 0xfff;146 } else {147 *val = st->dac_cache[chan->address];148 }149 150 return IIO_VAL_INT;151 case IIO_CHAN_INFO_SCALE:152 reg = &st->vref_reg[chan->channel];153 scale_uv = regulator_get_voltage(reg->consumer);154 if (scale_uv < 0)155 return scale_uv;156 157 *val = scale_uv / 1000;158 *val2 = chan->scan_type.realbits;159 160 return IIO_VAL_FRACTIONAL_LOG2;161 default:162 break;163 }164 165 return -EINVAL;166}167 168static int ad5449_write_raw(struct iio_dev *indio_dev,169 struct iio_chan_spec const *chan, int val, int val2, long info)170{171 struct ad5449 *st = iio_priv(indio_dev);172 int ret;173 174 switch (info) {175 case IIO_CHAN_INFO_RAW:176 if (val < 0 || val >= (1 << chan->scan_type.realbits))177 return -EINVAL;178 179 ret = ad5449_write(indio_dev,180 AD5449_CMD_LOAD_AND_UPDATE(chan->address),181 val << chan->scan_type.shift);182 if (ret == 0)183 st->dac_cache[chan->address] = val;184 break;185 default:186 ret = -EINVAL;187 }188 189 return ret;190}191 192static const struct iio_info ad5449_info = {193 .read_raw = ad5449_read_raw,194 .write_raw = ad5449_write_raw,195};196 197#define AD5449_CHANNEL(chan, bits) { \198 .type = IIO_VOLTAGE, \199 .indexed = 1, \200 .output = 1, \201 .channel = (chan), \202 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \203 BIT(IIO_CHAN_INFO_SCALE), \204 .address = (chan), \205 .scan_type = { \206 .sign = 'u', \207 .realbits = (bits), \208 .storagebits = 16, \209 .shift = 12 - (bits), \210 }, \211}212 213#define DECLARE_AD5449_CHANNELS(name, bits) \214const struct iio_chan_spec name[] = { \215 AD5449_CHANNEL(0, bits), \216 AD5449_CHANNEL(1, bits), \217}218 219static DECLARE_AD5449_CHANNELS(ad5429_channels, 8);220static DECLARE_AD5449_CHANNELS(ad5439_channels, 10);221static DECLARE_AD5449_CHANNELS(ad5449_channels, 12);222 223static const struct ad5449_chip_info ad5449_chip_info[] = {224 [ID_AD5426] = {225 .channels = ad5429_channels,226 .num_channels = 1,227 .has_ctrl = false,228 },229 [ID_AD5429] = {230 .channels = ad5429_channels,231 .num_channels = 2,232 .has_ctrl = true,233 },234 [ID_AD5432] = {235 .channels = ad5439_channels,236 .num_channels = 1,237 .has_ctrl = false,238 },239 [ID_AD5439] = {240 .channels = ad5439_channels,241 .num_channels = 2,242 .has_ctrl = true,243 },244 [ID_AD5443] = {245 .channels = ad5449_channels,246 .num_channels = 1,247 .has_ctrl = false,248 },249 [ID_AD5449] = {250 .channels = ad5449_channels,251 .num_channels = 2,252 .has_ctrl = true,253 },254};255 256static const char *ad5449_vref_name(struct ad5449 *st, int n)257{258 if (st->chip_info->num_channels == 1)259 return "VREF";260 261 if (n == 0)262 return "VREFA";263 else264 return "VREFB";265}266 267static int ad5449_spi_probe(struct spi_device *spi)268{269 const struct spi_device_id *id = spi_get_device_id(spi);270 struct iio_dev *indio_dev;271 struct ad5449 *st;272 unsigned int i;273 int ret;274 275 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));276 if (indio_dev == NULL)277 return -ENOMEM;278 279 st = iio_priv(indio_dev);280 spi_set_drvdata(spi, indio_dev);281 282 st->chip_info = &ad5449_chip_info[id->driver_data];283 st->spi = spi;284 285 for (i = 0; i < st->chip_info->num_channels; ++i)286 st->vref_reg[i].supply = ad5449_vref_name(st, i);287 288 ret = devm_regulator_bulk_get(&spi->dev, st->chip_info->num_channels,289 st->vref_reg);290 if (ret)291 return ret;292 293 ret = regulator_bulk_enable(st->chip_info->num_channels, st->vref_reg);294 if (ret)295 return ret;296 297 indio_dev->name = id->name;298 indio_dev->info = &ad5449_info;299 indio_dev->modes = INDIO_DIRECT_MODE;300 indio_dev->channels = st->chip_info->channels;301 indio_dev->num_channels = st->chip_info->num_channels;302 303 mutex_init(&st->lock);304 305 if (st->chip_info->has_ctrl) {306 st->has_sdo = true;307 ad5449_write(indio_dev, AD5449_CMD_CTRL, 0x0);308 }309 310 ret = iio_device_register(indio_dev);311 if (ret)312 goto error_disable_reg;313 314 return 0;315 316error_disable_reg:317 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);318 319 return ret;320}321 322static void ad5449_spi_remove(struct spi_device *spi)323{324 struct iio_dev *indio_dev = spi_get_drvdata(spi);325 struct ad5449 *st = iio_priv(indio_dev);326 327 iio_device_unregister(indio_dev);328 329 regulator_bulk_disable(st->chip_info->num_channels, st->vref_reg);330}331 332static const struct spi_device_id ad5449_spi_ids[] = {333 { "ad5415", ID_AD5449 },334 { "ad5426", ID_AD5426 },335 { "ad5429", ID_AD5429 },336 { "ad5432", ID_AD5432 },337 { "ad5439", ID_AD5439 },338 { "ad5443", ID_AD5443 },339 { "ad5449", ID_AD5449 },340 {}341};342MODULE_DEVICE_TABLE(spi, ad5449_spi_ids);343 344static struct spi_driver ad5449_spi_driver = {345 .driver = {346 .name = "ad5449",347 },348 .probe = ad5449_spi_probe,349 .remove = ad5449_spi_remove,350 .id_table = ad5449_spi_ids,351};352module_spi_driver(ad5449_spi_driver);353 354MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");355MODULE_DESCRIPTION("Analog Devices AD5449 and similar DACs");356MODULE_LICENSE("GPL v2");357