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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AD5760, AD5780, AD5781, AD5790, AD5791 Voltage Output Digital to Analog4 * Converter5 *6 * Copyright 2011 Analog Devices Inc.7 */8 9#include <linux/interrupt.h>10#include <linux/fs.h>11#include <linux/device.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#include <linux/module.h>18#include <linux/bitops.h>19 20#include <linux/iio/iio.h>21#include <linux/iio/sysfs.h>22#include <linux/iio/dac/ad5791.h>23 24#define AD5791_DAC_MASK GENMASK(19, 0)25 26#define AD5791_CMD_READ BIT(23)27#define AD5791_CMD_WRITE 028#define AD5791_ADDR(addr) ((addr) << 20)29 30/* Registers */31#define AD5791_ADDR_NOOP 032#define AD5791_ADDR_DAC0 133#define AD5791_ADDR_CTRL 234#define AD5791_ADDR_CLRCODE 335#define AD5791_ADDR_SW_CTRL 436 37/* Control Register */38#define AD5791_CTRL_RBUF BIT(1)39#define AD5791_CTRL_OPGND BIT(2)40#define AD5791_CTRL_DACTRI BIT(3)41#define AD5791_CTRL_BIN2SC BIT(4)42#define AD5791_CTRL_SDODIS BIT(5)43#define AD5761_CTRL_LINCOMP(x) ((x) << 6)44 45#define AD5791_LINCOMP_0_10 046#define AD5791_LINCOMP_10_12 147#define AD5791_LINCOMP_12_16 248#define AD5791_LINCOMP_16_19 349#define AD5791_LINCOMP_19_20 1250 51#define AD5780_LINCOMP_0_10 052#define AD5780_LINCOMP_10_20 1253 54/* Software Control Register */55#define AD5791_SWCTRL_LDAC BIT(0)56#define AD5791_SWCTRL_CLR BIT(1)57#define AD5791_SWCTRL_RESET BIT(2)58 59#define AD5791_DAC_PWRDN_6K 060#define AD5791_DAC_PWRDN_3STATE 161 62/**63 * struct ad5791_chip_info - chip specific information64 * @get_lin_comp: function pointer to the device specific function65 */66 67struct ad5791_chip_info {68 int (*get_lin_comp) (unsigned int span);69};70 71/**72 * struct ad5791_state - driver instance specific data73 * @spi: spi_device74 * @reg_vdd: positive supply regulator75 * @reg_vss: negative supply regulator76 * @chip_info: chip model specific constants77 * @vref_mv: actual reference voltage used78 * @vref_neg_mv: voltage of the negative supply79 * @ctrl: control register cache80 * @pwr_down_mode: current power down mode81 * @pwr_down: true if device is powered down82 * @data: spi transfer buffers83 */84struct ad5791_state {85 struct spi_device *spi;86 struct regulator *reg_vdd;87 struct regulator *reg_vss;88 const struct ad5791_chip_info *chip_info;89 unsigned short vref_mv;90 unsigned int vref_neg_mv;91 unsigned ctrl;92 unsigned pwr_down_mode;93 bool pwr_down;94 95 union {96 __be32 d32;97 u8 d8[4];98 } data[3] __aligned(IIO_DMA_MINALIGN);99};100 101enum ad5791_supported_device_ids {102 ID_AD5760,103 ID_AD5780,104 ID_AD5781,105 ID_AD5791,106};107 108static int ad5791_spi_write(struct ad5791_state *st, u8 addr, u32 val)109{110 st->data[0].d32 = cpu_to_be32(AD5791_CMD_WRITE |111 AD5791_ADDR(addr) |112 (val & AD5791_DAC_MASK));113 114 return spi_write(st->spi, &st->data[0].d8[1], 3);115}116 117static int ad5791_spi_read(struct ad5791_state *st, u8 addr, u32 *val)118{119 int ret;120 struct spi_transfer xfers[] = {121 {122 .tx_buf = &st->data[0].d8[1],123 .bits_per_word = 8,124 .len = 3,125 .cs_change = 1,126 }, {127 .tx_buf = &st->data[1].d8[1],128 .rx_buf = &st->data[2].d8[1],129 .bits_per_word = 8,130 .len = 3,131 },132 };133 134 st->data[0].d32 = cpu_to_be32(AD5791_CMD_READ |135 AD5791_ADDR(addr));136 st->data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));137 138 ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));139 140 *val = be32_to_cpu(st->data[2].d32);141 142 return ret;143}144 145static const char * const ad5791_powerdown_modes[] = {146 "6kohm_to_gnd",147 "three_state",148};149 150static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev,151 const struct iio_chan_spec *chan)152{153 struct ad5791_state *st = iio_priv(indio_dev);154 155 return st->pwr_down_mode;156}157 158static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev,159 const struct iio_chan_spec *chan, unsigned int mode)160{161 struct ad5791_state *st = iio_priv(indio_dev);162 163 st->pwr_down_mode = mode;164 165 return 0;166}167 168static const struct iio_enum ad5791_powerdown_mode_enum = {169 .items = ad5791_powerdown_modes,170 .num_items = ARRAY_SIZE(ad5791_powerdown_modes),171 .get = ad5791_get_powerdown_mode,172 .set = ad5791_set_powerdown_mode,173};174 175static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev,176 uintptr_t private, const struct iio_chan_spec *chan, char *buf)177{178 struct ad5791_state *st = iio_priv(indio_dev);179 180 return sysfs_emit(buf, "%d\n", st->pwr_down);181}182 183static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev,184 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,185 size_t len)186{187 bool pwr_down;188 int ret;189 struct ad5791_state *st = iio_priv(indio_dev);190 191 ret = kstrtobool(buf, &pwr_down);192 if (ret)193 return ret;194 195 if (!pwr_down) {196 st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);197 } else {198 if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)199 st->ctrl |= AD5791_CTRL_OPGND;200 else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)201 st->ctrl |= AD5791_CTRL_DACTRI;202 }203 st->pwr_down = pwr_down;204 205 ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl);206 207 return ret ? ret : len;208}209 210static int ad5791_get_lin_comp(unsigned int span)211{212 if (span <= 10000)213 return AD5791_LINCOMP_0_10;214 else if (span <= 12000)215 return AD5791_LINCOMP_10_12;216 else if (span <= 16000)217 return AD5791_LINCOMP_12_16;218 else if (span <= 19000)219 return AD5791_LINCOMP_16_19;220 else221 return AD5791_LINCOMP_19_20;222}223 224static int ad5780_get_lin_comp(unsigned int span)225{226 if (span <= 10000)227 return AD5780_LINCOMP_0_10;228 else229 return AD5780_LINCOMP_10_20;230}231static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {232 [ID_AD5760] = {233 .get_lin_comp = ad5780_get_lin_comp,234 },235 [ID_AD5780] = {236 .get_lin_comp = ad5780_get_lin_comp,237 },238 [ID_AD5781] = {239 .get_lin_comp = ad5791_get_lin_comp,240 },241 [ID_AD5791] = {242 .get_lin_comp = ad5791_get_lin_comp,243 },244};245 246static int ad5791_read_raw(struct iio_dev *indio_dev,247 struct iio_chan_spec const *chan,248 int *val,249 int *val2,250 long m)251{252 struct ad5791_state *st = iio_priv(indio_dev);253 u64 val64;254 int ret;255 256 switch (m) {257 case IIO_CHAN_INFO_RAW:258 ret = ad5791_spi_read(st, chan->address, val);259 if (ret)260 return ret;261 *val &= AD5791_DAC_MASK;262 *val >>= chan->scan_type.shift;263 return IIO_VAL_INT;264 case IIO_CHAN_INFO_SCALE:265 *val = st->vref_mv;266 *val2 = (1 << chan->scan_type.realbits) - 1;267 return IIO_VAL_FRACTIONAL;268 case IIO_CHAN_INFO_OFFSET:269 val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);270 do_div(val64, st->vref_mv);271 *val = -val64;272 return IIO_VAL_INT;273 default:274 return -EINVAL;275 }276 277};278 279static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {280 {281 .name = "powerdown",282 .shared = IIO_SHARED_BY_TYPE,283 .read = ad5791_read_dac_powerdown,284 .write = ad5791_write_dac_powerdown,285 },286 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,287 &ad5791_powerdown_mode_enum),288 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5791_powerdown_mode_enum),289 { },290};291 292#define AD5791_CHAN(bits, _shift) { \293 .type = IIO_VOLTAGE, \294 .output = 1, \295 .indexed = 1, \296 .address = AD5791_ADDR_DAC0, \297 .channel = 0, \298 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \299 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \300 BIT(IIO_CHAN_INFO_OFFSET), \301 .scan_type = { \302 .sign = 'u', \303 .realbits = (bits), \304 .storagebits = 24, \305 .shift = (_shift), \306 }, \307 .ext_info = ad5791_ext_info, \308}309 310static const struct iio_chan_spec ad5791_channels[] = {311 [ID_AD5760] = AD5791_CHAN(16, 4),312 [ID_AD5780] = AD5791_CHAN(18, 2),313 [ID_AD5781] = AD5791_CHAN(18, 2),314 [ID_AD5791] = AD5791_CHAN(20, 0)315};316 317static int ad5791_write_raw(struct iio_dev *indio_dev,318 struct iio_chan_spec const *chan,319 int val,320 int val2,321 long mask)322{323 struct ad5791_state *st = iio_priv(indio_dev);324 325 switch (mask) {326 case IIO_CHAN_INFO_RAW:327 val &= GENMASK(chan->scan_type.realbits - 1, 0);328 val <<= chan->scan_type.shift;329 330 return ad5791_spi_write(st, chan->address, val);331 332 default:333 return -EINVAL;334 }335}336 337static const struct iio_info ad5791_info = {338 .read_raw = &ad5791_read_raw,339 .write_raw = &ad5791_write_raw,340};341 342static int ad5791_probe(struct spi_device *spi)343{344 struct ad5791_platform_data *pdata = spi->dev.platform_data;345 struct iio_dev *indio_dev;346 struct ad5791_state *st;347 int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;348 bool use_rbuf_gain2;349 350 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));351 if (!indio_dev)352 return -ENOMEM;353 st = iio_priv(indio_dev);354 st->reg_vdd = devm_regulator_get(&spi->dev, "vdd");355 if (!IS_ERR(st->reg_vdd)) {356 ret = regulator_enable(st->reg_vdd);357 if (ret)358 return ret;359 360 ret = regulator_get_voltage(st->reg_vdd);361 if (ret < 0)362 goto error_disable_reg_pos;363 364 pos_voltage_uv = ret;365 }366 367 st->reg_vss = devm_regulator_get(&spi->dev, "vss");368 if (!IS_ERR(st->reg_vss)) {369 ret = regulator_enable(st->reg_vss);370 if (ret)371 goto error_disable_reg_pos;372 373 ret = regulator_get_voltage(st->reg_vss);374 if (ret < 0)375 goto error_disable_reg_neg;376 377 neg_voltage_uv = ret;378 }379 380 st->pwr_down = true;381 st->spi = spi;382 383 if (pdata)384 use_rbuf_gain2 = pdata->use_rbuf_gain2;385 else386 use_rbuf_gain2 = device_property_read_bool(&spi->dev,387 "adi,rbuf-gain2-en");388 389 if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {390 st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;391 st->vref_neg_mv = neg_voltage_uv / 1000;392 } else if (pdata) {393 st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;394 st->vref_neg_mv = pdata->vref_neg_mv;395 } else {396 dev_warn(&spi->dev, "reference voltage unspecified\n");397 }398 399 ret = ad5791_spi_write(st, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);400 if (ret)401 goto error_disable_reg_neg;402 403 st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi)404 ->driver_data];405 406 407 st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))408 | (use_rbuf_gain2 ? 0 : AD5791_CTRL_RBUF) |409 AD5791_CTRL_BIN2SC;410 411 ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl |412 AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);413 if (ret)414 goto error_disable_reg_neg;415 416 spi_set_drvdata(spi, indio_dev);417 indio_dev->info = &ad5791_info;418 indio_dev->modes = INDIO_DIRECT_MODE;419 indio_dev->channels420 = &ad5791_channels[spi_get_device_id(spi)->driver_data];421 indio_dev->num_channels = 1;422 indio_dev->name = spi_get_device_id(st->spi)->name;423 ret = iio_device_register(indio_dev);424 if (ret)425 goto error_disable_reg_neg;426 427 return 0;428 429error_disable_reg_neg:430 if (!IS_ERR(st->reg_vss))431 regulator_disable(st->reg_vss);432error_disable_reg_pos:433 if (!IS_ERR(st->reg_vdd))434 regulator_disable(st->reg_vdd);435 return ret;436}437 438static void ad5791_remove(struct spi_device *spi)439{440 struct iio_dev *indio_dev = spi_get_drvdata(spi);441 struct ad5791_state *st = iio_priv(indio_dev);442 443 iio_device_unregister(indio_dev);444 if (!IS_ERR(st->reg_vdd))445 regulator_disable(st->reg_vdd);446 447 if (!IS_ERR(st->reg_vss))448 regulator_disable(st->reg_vss);449}450 451static const struct spi_device_id ad5791_id[] = {452 {"ad5760", ID_AD5760},453 {"ad5780", ID_AD5780},454 {"ad5781", ID_AD5781},455 {"ad5790", ID_AD5791},456 {"ad5791", ID_AD5791},457 {}458};459MODULE_DEVICE_TABLE(spi, ad5791_id);460 461static struct spi_driver ad5791_driver = {462 .driver = {463 .name = "ad5791",464 },465 .probe = ad5791_probe,466 .remove = ad5791_remove,467 .id_table = ad5791_id,468};469module_spi_driver(ad5791_driver);470 471MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");472MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC");473MODULE_LICENSE("GPL v2");474