linux/drivers/iio/dac/ad5755.c
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   1/*
   2 * AD5755, AD5755-1, AD5757, AD5735, AD5737 Digital to analog converters driver
   3 *
   4 * Copyright 2012 Analog Devices Inc.
   5 *
   6 * Licensed under the GPL-2.
   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/delay.h>
  17#include <linux/of.h>
  18#include <linux/iio/iio.h>
  19#include <linux/iio/sysfs.h>
  20#include <linux/platform_data/ad5755.h>
  21
  22#define AD5755_NUM_CHANNELS 4
  23
  24#define AD5755_ADDR(x)                  ((x) << 16)
  25
  26#define AD5755_WRITE_REG_DATA(chan)     (chan)
  27#define AD5755_WRITE_REG_GAIN(chan)     (0x08 | (chan))
  28#define AD5755_WRITE_REG_OFFSET(chan)   (0x10 | (chan))
  29#define AD5755_WRITE_REG_CTRL(chan)     (0x1c | (chan))
  30
  31#define AD5755_READ_REG_DATA(chan)      (chan)
  32#define AD5755_READ_REG_CTRL(chan)      (0x4 | (chan))
  33#define AD5755_READ_REG_GAIN(chan)      (0x8 | (chan))
  34#define AD5755_READ_REG_OFFSET(chan)    (0xc | (chan))
  35#define AD5755_READ_REG_CLEAR(chan)     (0x10 | (chan))
  36#define AD5755_READ_REG_SLEW(chan)      (0x14 | (chan))
  37#define AD5755_READ_REG_STATUS          0x18
  38#define AD5755_READ_REG_MAIN            0x19
  39#define AD5755_READ_REG_DC_DC           0x1a
  40
  41#define AD5755_CTRL_REG_SLEW    0x0
  42#define AD5755_CTRL_REG_MAIN    0x1
  43#define AD5755_CTRL_REG_DAC     0x2
  44#define AD5755_CTRL_REG_DC_DC   0x3
  45#define AD5755_CTRL_REG_SW      0x4
  46
  47#define AD5755_READ_FLAG 0x800000
  48
  49#define AD5755_NOOP 0x1CE000
  50
  51#define AD5755_DAC_INT_EN                       BIT(8)
  52#define AD5755_DAC_CLR_EN                       BIT(7)
  53#define AD5755_DAC_OUT_EN                       BIT(6)
  54#define AD5755_DAC_INT_CURRENT_SENSE_RESISTOR   BIT(5)
  55#define AD5755_DAC_DC_DC_EN                     BIT(4)
  56#define AD5755_DAC_VOLTAGE_OVERRANGE_EN         BIT(3)
  57
  58#define AD5755_DC_DC_MAXV                       0
  59#define AD5755_DC_DC_FREQ_SHIFT                 2
  60#define AD5755_DC_DC_PHASE_SHIFT                4
  61#define AD5755_EXT_DC_DC_COMP_RES               BIT(6)
  62
  63#define AD5755_SLEW_STEP_SIZE_SHIFT             0
  64#define AD5755_SLEW_RATE_SHIFT                  3
  65#define AD5755_SLEW_ENABLE                      BIT(12)
  66
  67/**
  68 * struct ad5755_chip_info - chip specific information
  69 * @channel_template:   channel specification
  70 * @calib_shift:        shift for the calibration data registers
  71 * @has_voltage_out:    whether the chip has voltage outputs
  72 */
  73struct ad5755_chip_info {
  74        const struct iio_chan_spec channel_template;
  75        unsigned int calib_shift;
  76        bool has_voltage_out;
  77};
  78
  79/**
  80 * struct ad5755_state - driver instance specific data
  81 * @spi:        spi device the driver is attached to
  82 * @chip_info:  chip model specific constants, available modes etc
  83 * @pwr_down:   bitmask which contains  hether a channel is powered down or not
  84 * @ctrl:       software shadow of the channel ctrl registers
  85 * @channels:   iio channel spec for the device
  86 * @data:       spi transfer buffers
  87 */
  88struct ad5755_state {
  89        struct spi_device               *spi;
  90        const struct ad5755_chip_info   *chip_info;
  91        unsigned int                    pwr_down;
  92        unsigned int                    ctrl[AD5755_NUM_CHANNELS];
  93        struct iio_chan_spec            channels[AD5755_NUM_CHANNELS];
  94
  95        /*
  96         * DMA (thus cache coherency maintenance) requires the
  97         * transfer buffers to live in their own cache lines.
  98         */
  99
 100        union {
 101                __be32 d32;
 102                u8 d8[4];
 103        } data[2] ____cacheline_aligned;
 104};
 105
 106enum ad5755_type {
 107        ID_AD5755,
 108        ID_AD5757,
 109        ID_AD5735,
 110        ID_AD5737,
 111};
 112
 113#ifdef CONFIG_OF
 114static const int ad5755_dcdc_freq_table[][2] = {
 115        { 250000, AD5755_DC_DC_FREQ_250kHZ },
 116        { 410000, AD5755_DC_DC_FREQ_410kHZ },
 117        { 650000, AD5755_DC_DC_FREQ_650kHZ }
 118};
 119
 120static const int ad5755_dcdc_maxv_table[][2] = {
 121        { 23000000, AD5755_DC_DC_MAXV_23V },
 122        { 24500000, AD5755_DC_DC_MAXV_24V5 },
 123        { 27000000, AD5755_DC_DC_MAXV_27V },
 124        { 29500000, AD5755_DC_DC_MAXV_29V5 },
 125};
 126
 127static const int ad5755_slew_rate_table[][2] = {
 128        { 64000, AD5755_SLEW_RATE_64k },
 129        { 32000, AD5755_SLEW_RATE_32k },
 130        { 16000, AD5755_SLEW_RATE_16k },
 131        { 8000, AD5755_SLEW_RATE_8k },
 132        { 4000, AD5755_SLEW_RATE_4k },
 133        { 2000, AD5755_SLEW_RATE_2k },
 134        { 1000, AD5755_SLEW_RATE_1k },
 135        { 500, AD5755_SLEW_RATE_500 },
 136        { 250, AD5755_SLEW_RATE_250 },
 137        { 125, AD5755_SLEW_RATE_125 },
 138        { 64, AD5755_SLEW_RATE_64 },
 139        { 32, AD5755_SLEW_RATE_32 },
 140        { 16, AD5755_SLEW_RATE_16 },
 141        { 8, AD5755_SLEW_RATE_8 },
 142        { 4, AD5755_SLEW_RATE_4 },
 143        { 0, AD5755_SLEW_RATE_0_5 },
 144};
 145
 146static const int ad5755_slew_step_table[][2] = {
 147        { 256, AD5755_SLEW_STEP_SIZE_256 },
 148        { 128, AD5755_SLEW_STEP_SIZE_128 },
 149        { 64, AD5755_SLEW_STEP_SIZE_64 },
 150        { 32, AD5755_SLEW_STEP_SIZE_32 },
 151        { 16, AD5755_SLEW_STEP_SIZE_16 },
 152        { 4, AD5755_SLEW_STEP_SIZE_4 },
 153        { 2, AD5755_SLEW_STEP_SIZE_2 },
 154        { 1, AD5755_SLEW_STEP_SIZE_1 },
 155};
 156#endif
 157
 158static int ad5755_write_unlocked(struct iio_dev *indio_dev,
 159        unsigned int reg, unsigned int val)
 160{
 161        struct ad5755_state *st = iio_priv(indio_dev);
 162
 163        st->data[0].d32 = cpu_to_be32((reg << 16) | val);
 164
 165        return spi_write(st->spi, &st->data[0].d8[1], 3);
 166}
 167
 168static int ad5755_write_ctrl_unlocked(struct iio_dev *indio_dev,
 169        unsigned int channel, unsigned int reg, unsigned int val)
 170{
 171        return ad5755_write_unlocked(indio_dev,
 172                AD5755_WRITE_REG_CTRL(channel), (reg << 13) | val);
 173}
 174
 175static int ad5755_write(struct iio_dev *indio_dev, unsigned int reg,
 176        unsigned int val)
 177{
 178        int ret;
 179
 180        mutex_lock(&indio_dev->mlock);
 181        ret = ad5755_write_unlocked(indio_dev, reg, val);
 182        mutex_unlock(&indio_dev->mlock);
 183
 184        return ret;
 185}
 186
 187static int ad5755_write_ctrl(struct iio_dev *indio_dev, unsigned int channel,
 188        unsigned int reg, unsigned int val)
 189{
 190        int ret;
 191
 192        mutex_lock(&indio_dev->mlock);
 193        ret = ad5755_write_ctrl_unlocked(indio_dev, channel, reg, val);
 194        mutex_unlock(&indio_dev->mlock);
 195
 196        return ret;
 197}
 198
 199static int ad5755_read(struct iio_dev *indio_dev, unsigned int addr)
 200{
 201        struct ad5755_state *st = iio_priv(indio_dev);
 202        int ret;
 203        struct spi_transfer t[] = {
 204                {
 205                        .tx_buf = &st->data[0].d8[1],
 206                        .len = 3,
 207                        .cs_change = 1,
 208                }, {
 209                        .tx_buf = &st->data[1].d8[1],
 210                        .rx_buf = &st->data[1].d8[1],
 211                        .len = 3,
 212                },
 213        };
 214
 215        mutex_lock(&indio_dev->mlock);
 216
 217        st->data[0].d32 = cpu_to_be32(AD5755_READ_FLAG | (addr << 16));
 218        st->data[1].d32 = cpu_to_be32(AD5755_NOOP);
 219
 220        ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
 221        if (ret >= 0)
 222                ret = be32_to_cpu(st->data[1].d32) & 0xffff;
 223
 224        mutex_unlock(&indio_dev->mlock);
 225
 226        return ret;
 227}
 228
 229static int ad5755_update_dac_ctrl(struct iio_dev *indio_dev,
 230        unsigned int channel, unsigned int set, unsigned int clr)
 231{
 232        struct ad5755_state *st = iio_priv(indio_dev);
 233        int ret;
 234
 235        st->ctrl[channel] |= set;
 236        st->ctrl[channel] &= ~clr;
 237
 238        ret = ad5755_write_ctrl_unlocked(indio_dev, channel,
 239                AD5755_CTRL_REG_DAC, st->ctrl[channel]);
 240
 241        return ret;
 242}
 243
 244static int ad5755_set_channel_pwr_down(struct iio_dev *indio_dev,
 245        unsigned int channel, bool pwr_down)
 246{
 247        struct ad5755_state *st = iio_priv(indio_dev);
 248        unsigned int mask = BIT(channel);
 249
 250        mutex_lock(&indio_dev->mlock);
 251
 252        if ((bool)(st->pwr_down & mask) == pwr_down)
 253                goto out_unlock;
 254
 255        if (!pwr_down) {
 256                st->pwr_down &= ~mask;
 257                ad5755_update_dac_ctrl(indio_dev, channel,
 258                        AD5755_DAC_INT_EN | AD5755_DAC_DC_DC_EN, 0);
 259                udelay(200);
 260                ad5755_update_dac_ctrl(indio_dev, channel,
 261                        AD5755_DAC_OUT_EN, 0);
 262        } else {
 263                st->pwr_down |= mask;
 264                ad5755_update_dac_ctrl(indio_dev, channel,
 265                        0, AD5755_DAC_INT_EN | AD5755_DAC_OUT_EN |
 266                                AD5755_DAC_DC_DC_EN);
 267        }
 268
 269out_unlock:
 270        mutex_unlock(&indio_dev->mlock);
 271
 272        return 0;
 273}
 274
 275static const int ad5755_min_max_table[][2] = {
 276        [AD5755_MODE_VOLTAGE_0V_5V] = { 0, 5000 },
 277        [AD5755_MODE_VOLTAGE_0V_10V] = { 0, 10000 },
 278        [AD5755_MODE_VOLTAGE_PLUSMINUS_5V] = { -5000, 5000 },
 279        [AD5755_MODE_VOLTAGE_PLUSMINUS_10V] = { -10000, 10000 },
 280        [AD5755_MODE_CURRENT_4mA_20mA] = { 4, 20 },
 281        [AD5755_MODE_CURRENT_0mA_20mA] = { 0, 20 },
 282        [AD5755_MODE_CURRENT_0mA_24mA] = { 0, 24 },
 283};
 284
 285static void ad5755_get_min_max(struct ad5755_state *st,
 286        struct iio_chan_spec const *chan, int *min, int *max)
 287{
 288        enum ad5755_mode mode = st->ctrl[chan->channel] & 7;
 289        *min = ad5755_min_max_table[mode][0];
 290        *max = ad5755_min_max_table[mode][1];
 291}
 292
 293static inline int ad5755_get_offset(struct ad5755_state *st,
 294        struct iio_chan_spec const *chan)
 295{
 296        int min, max;
 297
 298        ad5755_get_min_max(st, chan, &min, &max);
 299        return (min * (1 << chan->scan_type.realbits)) / (max - min);
 300}
 301
 302static int ad5755_chan_reg_info(struct ad5755_state *st,
 303        struct iio_chan_spec const *chan, long info, bool write,
 304        unsigned int *reg, unsigned int *shift, unsigned int *offset)
 305{
 306        switch (info) {
 307        case IIO_CHAN_INFO_RAW:
 308                if (write)
 309                        *reg = AD5755_WRITE_REG_DATA(chan->address);
 310                else
 311                        *reg = AD5755_READ_REG_DATA(chan->address);
 312                *shift = chan->scan_type.shift;
 313                *offset = 0;
 314                break;
 315        case IIO_CHAN_INFO_CALIBBIAS:
 316                if (write)
 317                        *reg = AD5755_WRITE_REG_OFFSET(chan->address);
 318                else
 319                        *reg = AD5755_READ_REG_OFFSET(chan->address);
 320                *shift = st->chip_info->calib_shift;
 321                *offset = 32768;
 322                break;
 323        case IIO_CHAN_INFO_CALIBSCALE:
 324                if (write)
 325                        *reg =  AD5755_WRITE_REG_GAIN(chan->address);
 326                else
 327                        *reg =  AD5755_READ_REG_GAIN(chan->address);
 328                *shift = st->chip_info->calib_shift;
 329                *offset = 0;
 330                break;
 331        default:
 332                return -EINVAL;
 333        }
 334
 335        return 0;
 336}
 337
 338static int ad5755_read_raw(struct iio_dev *indio_dev,
 339        const struct iio_chan_spec *chan, int *val, int *val2, long info)
 340{
 341        struct ad5755_state *st = iio_priv(indio_dev);
 342        unsigned int reg, shift, offset;
 343        int min, max;
 344        int ret;
 345
 346        switch (info) {
 347        case IIO_CHAN_INFO_SCALE:
 348                ad5755_get_min_max(st, chan, &min, &max);
 349                *val = max - min;
 350                *val2 = chan->scan_type.realbits;
 351                return IIO_VAL_FRACTIONAL_LOG2;
 352        case IIO_CHAN_INFO_OFFSET:
 353                *val = ad5755_get_offset(st, chan);
 354                return IIO_VAL_INT;
 355        default:
 356                ret = ad5755_chan_reg_info(st, chan, info, false,
 357                                                &reg, &shift, &offset);
 358                if (ret)
 359                        return ret;
 360
 361                ret = ad5755_read(indio_dev, reg);
 362                if (ret < 0)
 363                        return ret;
 364
 365                *val = (ret - offset) >> shift;
 366
 367                return IIO_VAL_INT;
 368        }
 369
 370        return -EINVAL;
 371}
 372
 373static int ad5755_write_raw(struct iio_dev *indio_dev,
 374        const struct iio_chan_spec *chan, int val, int val2, long info)
 375{
 376        struct ad5755_state *st = iio_priv(indio_dev);
 377        unsigned int shift, reg, offset;
 378        int ret;
 379
 380        ret = ad5755_chan_reg_info(st, chan, info, true,
 381                                        &reg, &shift, &offset);
 382        if (ret)
 383                return ret;
 384
 385        val <<= shift;
 386        val += offset;
 387
 388        if (val < 0 || val > 0xffff)
 389                return -EINVAL;
 390
 391        return ad5755_write(indio_dev, reg, val);
 392}
 393
 394static ssize_t ad5755_read_powerdown(struct iio_dev *indio_dev, uintptr_t priv,
 395        const struct iio_chan_spec *chan, char *buf)
 396{
 397        struct ad5755_state *st = iio_priv(indio_dev);
 398
 399        return sprintf(buf, "%d\n",
 400                       (bool)(st->pwr_down & (1 << chan->channel)));
 401}
 402
 403static ssize_t ad5755_write_powerdown(struct iio_dev *indio_dev, uintptr_t priv,
 404        struct iio_chan_spec const *chan, const char *buf, size_t len)
 405{
 406        bool pwr_down;
 407        int ret;
 408
 409        ret = strtobool(buf, &pwr_down);
 410        if (ret)
 411                return ret;
 412
 413        ret = ad5755_set_channel_pwr_down(indio_dev, chan->channel, pwr_down);
 414        return ret ? ret : len;
 415}
 416
 417static const struct iio_info ad5755_info = {
 418        .read_raw = ad5755_read_raw,
 419        .write_raw = ad5755_write_raw,
 420        .driver_module = THIS_MODULE,
 421};
 422
 423static const struct iio_chan_spec_ext_info ad5755_ext_info[] = {
 424        {
 425                .name = "powerdown",
 426                .read = ad5755_read_powerdown,
 427                .write = ad5755_write_powerdown,
 428                .shared = IIO_SEPARATE,
 429        },
 430        { },
 431};
 432
 433#define AD5755_CHANNEL(_bits) {                                 \
 434        .indexed = 1,                                           \
 435        .output = 1,                                            \
 436        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
 437                BIT(IIO_CHAN_INFO_SCALE) |                      \
 438                BIT(IIO_CHAN_INFO_OFFSET) |                     \
 439                BIT(IIO_CHAN_INFO_CALIBSCALE) |                 \
 440                BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
 441        .scan_type = {                                          \
 442                .sign = 'u',                                    \
 443                .realbits = (_bits),                            \
 444                .storagebits = 16,                              \
 445                .shift = 16 - (_bits),                          \
 446        },                                                      \
 447        .ext_info = ad5755_ext_info,                            \
 448}
 449
 450static const struct ad5755_chip_info ad5755_chip_info_tbl[] = {
 451        [ID_AD5735] = {
 452                .channel_template = AD5755_CHANNEL(14),
 453                .has_voltage_out = true,
 454                .calib_shift = 4,
 455        },
 456        [ID_AD5737] = {
 457                .channel_template = AD5755_CHANNEL(14),
 458                .has_voltage_out = false,
 459                .calib_shift = 4,
 460        },
 461        [ID_AD5755] = {
 462                .channel_template = AD5755_CHANNEL(16),
 463                .has_voltage_out = true,
 464                .calib_shift = 0,
 465        },
 466        [ID_AD5757] = {
 467                .channel_template = AD5755_CHANNEL(16),
 468                .has_voltage_out = false,
 469                .calib_shift = 0,
 470        },
 471};
 472
 473static bool ad5755_is_valid_mode(struct ad5755_state *st, enum ad5755_mode mode)
 474{
 475        switch (mode) {
 476        case AD5755_MODE_VOLTAGE_0V_5V:
 477        case AD5755_MODE_VOLTAGE_0V_10V:
 478        case AD5755_MODE_VOLTAGE_PLUSMINUS_5V:
 479        case AD5755_MODE_VOLTAGE_PLUSMINUS_10V:
 480                return st->chip_info->has_voltage_out;
 481        case AD5755_MODE_CURRENT_4mA_20mA:
 482        case AD5755_MODE_CURRENT_0mA_20mA:
 483        case AD5755_MODE_CURRENT_0mA_24mA:
 484                return true;
 485        default:
 486                return false;
 487        }
 488}
 489
 490static int ad5755_setup_pdata(struct iio_dev *indio_dev,
 491                              const struct ad5755_platform_data *pdata)
 492{
 493        struct ad5755_state *st = iio_priv(indio_dev);
 494        unsigned int val;
 495        unsigned int i;
 496        int ret;
 497
 498        if (pdata->dc_dc_phase > AD5755_DC_DC_PHASE_90_DEGREE ||
 499                pdata->dc_dc_freq > AD5755_DC_DC_FREQ_650kHZ ||
 500                pdata->dc_dc_maxv > AD5755_DC_DC_MAXV_29V5)
 501                return -EINVAL;
 502
 503        val = pdata->dc_dc_maxv << AD5755_DC_DC_MAXV;
 504        val |= pdata->dc_dc_freq << AD5755_DC_DC_FREQ_SHIFT;
 505        val |= pdata->dc_dc_phase << AD5755_DC_DC_PHASE_SHIFT;
 506        if (pdata->ext_dc_dc_compenstation_resistor)
 507                val |= AD5755_EXT_DC_DC_COMP_RES;
 508
 509        ret = ad5755_write_ctrl(indio_dev, 0, AD5755_CTRL_REG_DC_DC, val);
 510        if (ret < 0)
 511                return ret;
 512
 513        for (i = 0; i < ARRAY_SIZE(pdata->dac); ++i) {
 514                val = pdata->dac[i].slew.step_size <<
 515                        AD5755_SLEW_STEP_SIZE_SHIFT;
 516                val |= pdata->dac[i].slew.rate <<
 517                        AD5755_SLEW_RATE_SHIFT;
 518                if (pdata->dac[i].slew.enable)
 519                        val |= AD5755_SLEW_ENABLE;
 520
 521                ret = ad5755_write_ctrl(indio_dev, i,
 522                                        AD5755_CTRL_REG_SLEW, val);
 523                if (ret < 0)
 524                        return ret;
 525        }
 526
 527        for (i = 0; i < ARRAY_SIZE(pdata->dac); ++i) {
 528                if (!ad5755_is_valid_mode(st, pdata->dac[i].mode))
 529                        return -EINVAL;
 530
 531                val = 0;
 532                if (!pdata->dac[i].ext_current_sense_resistor)
 533                        val |= AD5755_DAC_INT_CURRENT_SENSE_RESISTOR;
 534                if (pdata->dac[i].enable_voltage_overrange)
 535                        val |= AD5755_DAC_VOLTAGE_OVERRANGE_EN;
 536                val |= pdata->dac[i].mode;
 537
 538                ret = ad5755_update_dac_ctrl(indio_dev, i, val, 0);
 539                if (ret < 0)
 540                        return ret;
 541        }
 542
 543        return 0;
 544}
 545
 546static bool ad5755_is_voltage_mode(enum ad5755_mode mode)
 547{
 548        switch (mode) {
 549        case AD5755_MODE_VOLTAGE_0V_5V:
 550        case AD5755_MODE_VOLTAGE_0V_10V:
 551        case AD5755_MODE_VOLTAGE_PLUSMINUS_5V:
 552        case AD5755_MODE_VOLTAGE_PLUSMINUS_10V:
 553                return true;
 554        default:
 555                return false;
 556        }
 557}
 558
 559static int ad5755_init_channels(struct iio_dev *indio_dev,
 560                                const struct ad5755_platform_data *pdata)
 561{
 562        struct ad5755_state *st = iio_priv(indio_dev);
 563        struct iio_chan_spec *channels = st->channels;
 564        unsigned int i;
 565
 566        for (i = 0; i < AD5755_NUM_CHANNELS; ++i) {
 567                channels[i] = st->chip_info->channel_template;
 568                channels[i].channel = i;
 569                channels[i].address = i;
 570                if (pdata && ad5755_is_voltage_mode(pdata->dac[i].mode))
 571                        channels[i].type = IIO_VOLTAGE;
 572                else
 573                        channels[i].type = IIO_CURRENT;
 574        }
 575
 576        indio_dev->channels = channels;
 577
 578        return 0;
 579}
 580
 581#define AD5755_DEFAULT_DAC_PDATA { \
 582                .mode = AD5755_MODE_CURRENT_4mA_20mA, \
 583                .ext_current_sense_resistor = true, \
 584                .enable_voltage_overrange = false, \
 585                .slew = { \
 586                        .enable = false, \
 587                        .rate = AD5755_SLEW_RATE_64k, \
 588                        .step_size = AD5755_SLEW_STEP_SIZE_1, \
 589                }, \
 590        }
 591
 592static const struct ad5755_platform_data ad5755_default_pdata = {
 593        .ext_dc_dc_compenstation_resistor = false,
 594        .dc_dc_phase = AD5755_DC_DC_PHASE_ALL_SAME_EDGE,
 595        .dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ,
 596        .dc_dc_maxv = AD5755_DC_DC_MAXV_23V,
 597        .dac = {
 598                [0] = AD5755_DEFAULT_DAC_PDATA,
 599                [1] = AD5755_DEFAULT_DAC_PDATA,
 600                [2] = AD5755_DEFAULT_DAC_PDATA,
 601                [3] = AD5755_DEFAULT_DAC_PDATA,
 602        },
 603};
 604
 605#ifdef CONFIG_OF
 606static struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)
 607{
 608        struct device_node *np = dev->of_node;
 609        struct device_node *pp;
 610        struct ad5755_platform_data *pdata;
 611        unsigned int tmp;
 612        unsigned int tmparray[3];
 613        int devnr, i;
 614
 615        pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 616        if (!pdata)
 617                return NULL;
 618
 619        pdata->ext_dc_dc_compenstation_resistor =
 620            of_property_read_bool(np, "adi,ext-dc-dc-compenstation-resistor");
 621
 622        if (!of_property_read_u32(np, "adi,dc-dc-phase", &tmp))
 623                pdata->dc_dc_phase = tmp;
 624        else
 625                pdata->dc_dc_phase = AD5755_DC_DC_PHASE_ALL_SAME_EDGE;
 626
 627        pdata->dc_dc_freq = AD5755_DC_DC_FREQ_410kHZ;
 628        if (!of_property_read_u32(np, "adi,dc-dc-freq-hz", &tmp)) {
 629                for (i = 0; i < ARRAY_SIZE(ad5755_dcdc_freq_table); i++) {
 630                        if (tmp == ad5755_dcdc_freq_table[i][0]) {
 631                                pdata->dc_dc_freq = ad5755_dcdc_freq_table[i][1];
 632                                break;
 633                        }
 634                }
 635
 636                if (i == ARRAY_SIZE(ad5755_dcdc_freq_table)) {
 637                        dev_err(dev,
 638                                "adi,dc-dc-freq out of range selecting 410kHz");
 639                }
 640        }
 641
 642        pdata->dc_dc_maxv = AD5755_DC_DC_MAXV_23V;
 643        if (!of_property_read_u32(np, "adi,dc-dc-max-microvolt", &tmp)) {
 644                for (i = 0; i < ARRAY_SIZE(ad5755_dcdc_maxv_table); i++) {
 645                        if (tmp == ad5755_dcdc_maxv_table[i][0]) {
 646                                pdata->dc_dc_maxv = ad5755_dcdc_maxv_table[i][1];
 647                                break;
 648                        }
 649                }
 650                if (i == ARRAY_SIZE(ad5755_dcdc_maxv_table)) {
 651                                dev_err(dev,
 652                                        "adi,dc-dc-maxv out of range selecting 23V");
 653                }
 654        }
 655
 656        devnr = 0;
 657        for_each_child_of_node(np, pp) {
 658                if (devnr >= AD5755_NUM_CHANNELS) {
 659                        dev_err(dev,
 660                                "There is to many channels defined in DT\n");
 661                        goto error_out;
 662                }
 663
 664                if (!of_property_read_u32(pp, "adi,mode", &tmp))
 665                        pdata->dac[devnr].mode = tmp;
 666                else
 667                        pdata->dac[devnr].mode = AD5755_MODE_CURRENT_4mA_20mA;
 668
 669                pdata->dac[devnr].ext_current_sense_resistor =
 670                    of_property_read_bool(pp, "adi,ext-current-sense-resistor");
 671
 672                pdata->dac[devnr].enable_voltage_overrange =
 673                    of_property_read_bool(pp, "adi,enable-voltage-overrange");
 674
 675                if (!of_property_read_u32_array(pp, "adi,slew", tmparray, 3)) {
 676                        pdata->dac[devnr].slew.enable = tmparray[0];
 677
 678                        pdata->dac[devnr].slew.rate = AD5755_SLEW_RATE_64k;
 679                        for (i = 0; i < ARRAY_SIZE(ad5755_slew_rate_table); i++) {
 680                                if (tmparray[1] == ad5755_slew_rate_table[i][0]) {
 681                                        pdata->dac[devnr].slew.rate =
 682                                                ad5755_slew_rate_table[i][1];
 683                                        break;
 684                                }
 685                        }
 686                        if (i == ARRAY_SIZE(ad5755_slew_rate_table)) {
 687                                dev_err(dev,
 688                                        "channel %d slew rate out of range selecting 64kHz",
 689                                        devnr);
 690                        }
 691
 692                        pdata->dac[devnr].slew.step_size = AD5755_SLEW_STEP_SIZE_1;
 693                        for (i = 0; i < ARRAY_SIZE(ad5755_slew_step_table); i++) {
 694                                if (tmparray[2] == ad5755_slew_step_table[i][0]) {
 695                                        pdata->dac[devnr].slew.step_size =
 696                                                ad5755_slew_step_table[i][1];
 697                                        break;
 698                                }
 699                        }
 700                        if (i == ARRAY_SIZE(ad5755_slew_step_table)) {
 701                                dev_err(dev,
 702                                        "channel %d slew step size out of range selecting 1 LSB",
 703                                        devnr);
 704                        }
 705                } else {
 706                        pdata->dac[devnr].slew.enable = false;
 707                        pdata->dac[devnr].slew.rate = AD5755_SLEW_RATE_64k;
 708                        pdata->dac[devnr].slew.step_size =
 709                            AD5755_SLEW_STEP_SIZE_1;
 710                }
 711                devnr++;
 712        }
 713
 714        return pdata;
 715
 716 error_out:
 717        devm_kfree(dev, pdata);
 718        return NULL;
 719}
 720#else
 721static
 722struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)
 723{
 724        return NULL;
 725}
 726#endif
 727
 728static int ad5755_probe(struct spi_device *spi)
 729{
 730        enum ad5755_type type = spi_get_device_id(spi)->driver_data;
 731        const struct ad5755_platform_data *pdata = dev_get_platdata(&spi->dev);
 732        struct iio_dev *indio_dev;
 733        struct ad5755_state *st;
 734        int ret;
 735
 736        indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 737        if (indio_dev == NULL) {
 738                dev_err(&spi->dev, "Failed to allocate iio device\n");
 739                return  -ENOMEM;
 740        }
 741
 742        st = iio_priv(indio_dev);
 743        spi_set_drvdata(spi, indio_dev);
 744
 745        st->chip_info = &ad5755_chip_info_tbl[type];
 746        st->spi = spi;
 747        st->pwr_down = 0xf;
 748
 749        indio_dev->dev.parent = &spi->dev;
 750        indio_dev->name = spi_get_device_id(spi)->name;
 751        indio_dev->info = &ad5755_info;
 752        indio_dev->modes = INDIO_DIRECT_MODE;
 753        indio_dev->num_channels = AD5755_NUM_CHANNELS;
 754
 755        if (spi->dev.of_node)
 756                pdata = ad5755_parse_dt(&spi->dev);
 757        else
 758                pdata = spi->dev.platform_data;
 759
 760        if (!pdata) {
 761                dev_warn(&spi->dev, "no platform data? using default\n");
 762                pdata = &ad5755_default_pdata;
 763        }
 764
 765        ret = ad5755_init_channels(indio_dev, pdata);
 766        if (ret)
 767                return ret;
 768
 769        ret = ad5755_setup_pdata(indio_dev, pdata);
 770        if (ret)
 771                return ret;
 772
 773        return devm_iio_device_register(&spi->dev, indio_dev);
 774}
 775
 776static const struct spi_device_id ad5755_id[] = {
 777        { "ad5755", ID_AD5755 },
 778        { "ad5755-1", ID_AD5755 },
 779        { "ad5757", ID_AD5757 },
 780        { "ad5735", ID_AD5735 },
 781        { "ad5737", ID_AD5737 },
 782        {}
 783};
 784MODULE_DEVICE_TABLE(spi, ad5755_id);
 785
 786static const struct of_device_id ad5755_of_match[] = {
 787        { .compatible = "adi,ad5755" },
 788        { .compatible = "adi,ad5755-1" },
 789        { .compatible = "adi,ad5757" },
 790        { .compatible = "adi,ad5735" },
 791        { .compatible = "adi,ad5737" },
 792        { }
 793};
 794MODULE_DEVICE_TABLE(of, ad5755_of_match);
 795
 796static struct spi_driver ad5755_driver = {
 797        .driver = {
 798                .name = "ad5755",
 799        },
 800        .probe = ad5755_probe,
 801        .id_table = ad5755_id,
 802};
 803module_spi_driver(ad5755_driver);
 804
 805MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 806MODULE_DESCRIPTION("Analog Devices AD5755/55-1/57/35/37 DAC");
 807MODULE_LICENSE("GPL v2");
 808