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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AD5504, AD5501 High Voltage Digital to Analog Converter4 *5 * Copyright 2011 Analog Devices Inc.6 */7 8#include <linux/interrupt.h>9#include <linux/fs.h>10#include <linux/device.h>11#include <linux/kernel.h>12#include <linux/spi/spi.h>13#include <linux/slab.h>14#include <linux/sysfs.h>15#include <linux/regulator/consumer.h>16#include <linux/module.h>17#include <linux/bitops.h>18 19#include <linux/iio/iio.h>20#include <linux/iio/sysfs.h>21#include <linux/iio/events.h>22#include <linux/iio/dac/ad5504.h>23 24#define AD5504_RES_MASK GENMASK(11, 0)25#define AD5504_CMD_READ BIT(15)26#define AD5504_CMD_WRITE 027#define AD5504_ADDR(addr) ((addr) << 12)28 29/* Registers */30#define AD5504_ADDR_NOOP 031#define AD5504_ADDR_DAC(x) ((x) + 1)32#define AD5504_ADDR_ALL_DAC 533#define AD5504_ADDR_CTRL 734 35/* Control Register */36#define AD5504_DAC_PWR(ch) ((ch) << 2)37#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)38#define AD5504_DAC_PWRDN_20K 039#define AD5504_DAC_PWRDN_3STATE 140 41/**42 * struct ad5504_state - driver instance specific data43 * @spi: spi_device44 * @reg: supply regulator45 * @vref_mv: actual reference voltage used46 * @pwr_down_mask: power down mask47 * @pwr_down_mode: current power down mode48 * @data: transfer buffer49 */50struct ad5504_state {51 struct spi_device *spi;52 struct regulator *reg;53 unsigned short vref_mv;54 unsigned pwr_down_mask;55 unsigned pwr_down_mode;56 57 __be16 data[2] __aligned(IIO_DMA_MINALIGN);58};59 60/*61 * ad5504_supported_device_ids:62 */63enum ad5504_supported_device_ids {64 ID_AD5504,65 ID_AD5501,66};67 68static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)69{70 st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |71 (val & AD5504_RES_MASK));72 73 return spi_write(st->spi, &st->data[0], 2);74}75 76static int ad5504_spi_read(struct ad5504_state *st, u8 addr)77{78 int ret;79 struct spi_transfer t = {80 .tx_buf = &st->data[0],81 .rx_buf = &st->data[1],82 .len = 2,83 };84 85 st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));86 ret = spi_sync_transfer(st->spi, &t, 1);87 if (ret < 0)88 return ret;89 90 return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;91}92 93static int ad5504_read_raw(struct iio_dev *indio_dev,94 struct iio_chan_spec const *chan,95 int *val,96 int *val2,97 long m)98{99 struct ad5504_state *st = iio_priv(indio_dev);100 int ret;101 102 switch (m) {103 case IIO_CHAN_INFO_RAW:104 ret = ad5504_spi_read(st, chan->address);105 if (ret < 0)106 return ret;107 108 *val = ret;109 110 return IIO_VAL_INT;111 case IIO_CHAN_INFO_SCALE:112 *val = st->vref_mv;113 *val2 = chan->scan_type.realbits;114 return IIO_VAL_FRACTIONAL_LOG2;115 }116 return -EINVAL;117}118 119static int ad5504_write_raw(struct iio_dev *indio_dev,120 struct iio_chan_spec const *chan,121 int val,122 int val2,123 long mask)124{125 struct ad5504_state *st = iio_priv(indio_dev);126 127 switch (mask) {128 case IIO_CHAN_INFO_RAW:129 if (val >= (1 << chan->scan_type.realbits) || val < 0)130 return -EINVAL;131 132 return ad5504_spi_write(st, chan->address, val);133 default:134 return -EINVAL;135 }136}137 138static const char * const ad5504_powerdown_modes[] = {139 "20kohm_to_gnd",140 "three_state",141};142 143static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,144 const struct iio_chan_spec *chan)145{146 struct ad5504_state *st = iio_priv(indio_dev);147 148 return st->pwr_down_mode;149}150 151static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,152 const struct iio_chan_spec *chan, unsigned int mode)153{154 struct ad5504_state *st = iio_priv(indio_dev);155 156 st->pwr_down_mode = mode;157 158 return 0;159}160 161static const struct iio_enum ad5504_powerdown_mode_enum = {162 .items = ad5504_powerdown_modes,163 .num_items = ARRAY_SIZE(ad5504_powerdown_modes),164 .get = ad5504_get_powerdown_mode,165 .set = ad5504_set_powerdown_mode,166};167 168static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,169 uintptr_t private, const struct iio_chan_spec *chan, char *buf)170{171 struct ad5504_state *st = iio_priv(indio_dev);172 173 return sysfs_emit(buf, "%d\n",174 !(st->pwr_down_mask & (1 << chan->channel)));175}176 177static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,178 uintptr_t private, const struct iio_chan_spec *chan, const char *buf,179 size_t len)180{181 bool pwr_down;182 int ret;183 struct ad5504_state *st = iio_priv(indio_dev);184 185 ret = kstrtobool(buf, &pwr_down);186 if (ret)187 return ret;188 189 if (pwr_down)190 st->pwr_down_mask &= ~(1 << chan->channel);191 else192 st->pwr_down_mask |= (1 << chan->channel);193 194 ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,195 AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |196 AD5504_DAC_PWR(st->pwr_down_mask));197 198 /* writes to the CTRL register must be followed by a NOOP */199 ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);200 201 return ret ? ret : len;202}203 204static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");205static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");206 207static struct attribute *ad5504_ev_attributes[] = {208 &iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,209 &iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,210 NULL,211};212 213static const struct attribute_group ad5504_ev_attribute_group = {214 .attrs = ad5504_ev_attributes,215};216 217static irqreturn_t ad5504_event_handler(int irq, void *private)218{219 iio_push_event(private,220 IIO_UNMOD_EVENT_CODE(IIO_TEMP,221 0,222 IIO_EV_TYPE_THRESH,223 IIO_EV_DIR_RISING),224 iio_get_time_ns(private));225 226 return IRQ_HANDLED;227}228 229static const struct iio_info ad5504_info = {230 .write_raw = ad5504_write_raw,231 .read_raw = ad5504_read_raw,232 .event_attrs = &ad5504_ev_attribute_group,233};234 235static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {236 {237 .name = "powerdown",238 .read = ad5504_read_dac_powerdown,239 .write = ad5504_write_dac_powerdown,240 .shared = IIO_SEPARATE,241 },242 IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,243 &ad5504_powerdown_mode_enum),244 IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5504_powerdown_mode_enum),245 { },246};247 248#define AD5504_CHANNEL(_chan) { \249 .type = IIO_VOLTAGE, \250 .indexed = 1, \251 .output = 1, \252 .channel = (_chan), \253 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \254 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \255 .address = AD5504_ADDR_DAC(_chan), \256 .scan_type = { \257 .sign = 'u', \258 .realbits = 12, \259 .storagebits = 16, \260 }, \261 .ext_info = ad5504_ext_info, \262}263 264static const struct iio_chan_spec ad5504_channels[] = {265 AD5504_CHANNEL(0),266 AD5504_CHANNEL(1),267 AD5504_CHANNEL(2),268 AD5504_CHANNEL(3),269};270 271static int ad5504_probe(struct spi_device *spi)272{273 struct ad5504_platform_data *pdata = spi->dev.platform_data;274 struct iio_dev *indio_dev;275 struct ad5504_state *st;276 struct regulator *reg;277 int ret, voltage_uv = 0;278 279 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));280 if (!indio_dev)281 return -ENOMEM;282 reg = devm_regulator_get(&spi->dev, "vcc");283 if (!IS_ERR(reg)) {284 ret = regulator_enable(reg);285 if (ret)286 return ret;287 288 ret = regulator_get_voltage(reg);289 if (ret < 0)290 goto error_disable_reg;291 292 voltage_uv = ret;293 }294 295 spi_set_drvdata(spi, indio_dev);296 st = iio_priv(indio_dev);297 if (voltage_uv)298 st->vref_mv = voltage_uv / 1000;299 else if (pdata)300 st->vref_mv = pdata->vref_mv;301 else302 dev_warn(&spi->dev, "reference voltage unspecified\n");303 304 st->reg = reg;305 st->spi = spi;306 indio_dev->name = spi_get_device_id(st->spi)->name;307 indio_dev->info = &ad5504_info;308 if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)309 indio_dev->num_channels = 1;310 else311 indio_dev->num_channels = 4;312 indio_dev->channels = ad5504_channels;313 indio_dev->modes = INDIO_DIRECT_MODE;314 315 if (spi->irq) {316 ret = devm_request_threaded_irq(&spi->dev, spi->irq,317 NULL,318 &ad5504_event_handler,319 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,320 spi_get_device_id(st->spi)->name,321 indio_dev);322 if (ret)323 goto error_disable_reg;324 }325 326 ret = iio_device_register(indio_dev);327 if (ret)328 goto error_disable_reg;329 330 return 0;331 332error_disable_reg:333 if (!IS_ERR(reg))334 regulator_disable(reg);335 336 return ret;337}338 339static void ad5504_remove(struct spi_device *spi)340{341 struct iio_dev *indio_dev = spi_get_drvdata(spi);342 struct ad5504_state *st = iio_priv(indio_dev);343 344 iio_device_unregister(indio_dev);345 346 if (!IS_ERR(st->reg))347 regulator_disable(st->reg);348}349 350static const struct spi_device_id ad5504_id[] = {351 {"ad5504", ID_AD5504},352 {"ad5501", ID_AD5501},353 {}354};355MODULE_DEVICE_TABLE(spi, ad5504_id);356 357static struct spi_driver ad5504_driver = {358 .driver = {359 .name = "ad5504",360 },361 .probe = ad5504_probe,362 .remove = ad5504_remove,363 .id_table = ad5504_id,364};365module_spi_driver(ad5504_driver);366 367MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");368MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");369MODULE_LICENSE("GPL v2");370