linux/drivers/iio/adc/ad7793.c
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   1/*
   2 * AD7785/AD7792/AD7793/AD7794/AD7795 SPI ADC driver
   3 *
   4 * Copyright 2011-2012 Analog Devices Inc.
   5 *
   6 * Licensed under the GPL-2.
   7 */
   8
   9#include <linux/interrupt.h>
  10#include <linux/device.h>
  11#include <linux/kernel.h>
  12#include <linux/slab.h>
  13#include <linux/sysfs.h>
  14#include <linux/spi/spi.h>
  15#include <linux/regulator/consumer.h>
  16#include <linux/err.h>
  17#include <linux/sched.h>
  18#include <linux/delay.h>
  19#include <linux/module.h>
  20
  21#include <linux/iio/iio.h>
  22#include <linux/iio/sysfs.h>
  23#include <linux/iio/buffer.h>
  24#include <linux/iio/trigger.h>
  25#include <linux/iio/trigger_consumer.h>
  26#include <linux/iio/triggered_buffer.h>
  27#include <linux/iio/adc/ad_sigma_delta.h>
  28#include <linux/platform_data/ad7793.h>
  29
  30/* Registers */
  31#define AD7793_REG_COMM         0 /* Communications Register (WO, 8-bit) */
  32#define AD7793_REG_STAT         0 /* Status Register         (RO, 8-bit) */
  33#define AD7793_REG_MODE         1 /* Mode Register           (RW, 16-bit */
  34#define AD7793_REG_CONF         2 /* Configuration Register  (RW, 16-bit) */
  35#define AD7793_REG_DATA         3 /* Data Register           (RO, 16-/24-bit) */
  36#define AD7793_REG_ID           4 /* ID Register             (RO, 8-bit) */
  37#define AD7793_REG_IO           5 /* IO Register             (RO, 8-bit) */
  38#define AD7793_REG_OFFSET       6 /* Offset Register         (RW, 16-bit
  39                                   * (AD7792)/24-bit (AD7793)) */
  40#define AD7793_REG_FULLSALE     7 /* Full-Scale Register
  41                                   * (RW, 16-bit (AD7792)/24-bit (AD7793)) */
  42
  43/* Communications Register Bit Designations (AD7793_REG_COMM) */
  44#define AD7793_COMM_WEN         (1 << 7) /* Write Enable */
  45#define AD7793_COMM_WRITE       (0 << 6) /* Write Operation */
  46#define AD7793_COMM_READ        (1 << 6) /* Read Operation */
  47#define AD7793_COMM_ADDR(x)     (((x) & 0x7) << 3) /* Register Address */
  48#define AD7793_COMM_CREAD       (1 << 2) /* Continuous Read of Data Register */
  49
  50/* Status Register Bit Designations (AD7793_REG_STAT) */
  51#define AD7793_STAT_RDY         (1 << 7) /* Ready */
  52#define AD7793_STAT_ERR         (1 << 6) /* Error (Overrange, Underrange) */
  53#define AD7793_STAT_CH3         (1 << 2) /* Channel 3 */
  54#define AD7793_STAT_CH2         (1 << 1) /* Channel 2 */
  55#define AD7793_STAT_CH1         (1 << 0) /* Channel 1 */
  56
  57/* Mode Register Bit Designations (AD7793_REG_MODE) */
  58#define AD7793_MODE_SEL(x)      (((x) & 0x7) << 13) /* Operation Mode Select */
  59#define AD7793_MODE_SEL_MASK    (0x7 << 13) /* Operation Mode Select mask */
  60#define AD7793_MODE_CLKSRC(x)   (((x) & 0x3) << 6) /* ADC Clock Source Select */
  61#define AD7793_MODE_RATE(x)     ((x) & 0xF) /* Filter Update Rate Select */
  62
  63#define AD7793_MODE_CONT                0 /* Continuous Conversion Mode */
  64#define AD7793_MODE_SINGLE              1 /* Single Conversion Mode */
  65#define AD7793_MODE_IDLE                2 /* Idle Mode */
  66#define AD7793_MODE_PWRDN               3 /* Power-Down Mode */
  67#define AD7793_MODE_CAL_INT_ZERO        4 /* Internal Zero-Scale Calibration */
  68#define AD7793_MODE_CAL_INT_FULL        5 /* Internal Full-Scale Calibration */
  69#define AD7793_MODE_CAL_SYS_ZERO        6 /* System Zero-Scale Calibration */
  70#define AD7793_MODE_CAL_SYS_FULL        7 /* System Full-Scale Calibration */
  71
  72#define AD7793_CLK_INT          0 /* Internal 64 kHz Clock not
  73                                   * available at the CLK pin */
  74#define AD7793_CLK_INT_CO       1 /* Internal 64 kHz Clock available
  75                                   * at the CLK pin */
  76#define AD7793_CLK_EXT          2 /* External 64 kHz Clock */
  77#define AD7793_CLK_EXT_DIV2     3 /* External Clock divided by 2 */
  78
  79/* Configuration Register Bit Designations (AD7793_REG_CONF) */
  80#define AD7793_CONF_VBIAS(x)    (((x) & 0x3) << 14) /* Bias Voltage
  81                                                     * Generator Enable */
  82#define AD7793_CONF_BO_EN       (1 << 13) /* Burnout Current Enable */
  83#define AD7793_CONF_UNIPOLAR    (1 << 12) /* Unipolar/Bipolar Enable */
  84#define AD7793_CONF_BOOST       (1 << 11) /* Boost Enable */
  85#define AD7793_CONF_GAIN(x)     (((x) & 0x7) << 8) /* Gain Select */
  86#define AD7793_CONF_REFSEL(x)   ((x) << 6) /* INT/EXT Reference Select */
  87#define AD7793_CONF_BUF         (1 << 4) /* Buffered Mode Enable */
  88#define AD7793_CONF_CHAN(x)     ((x) & 0xf) /* Channel select */
  89#define AD7793_CONF_CHAN_MASK   0xf /* Channel select mask */
  90
  91#define AD7793_CH_AIN1P_AIN1M   0 /* AIN1(+) - AIN1(-) */
  92#define AD7793_CH_AIN2P_AIN2M   1 /* AIN2(+) - AIN2(-) */
  93#define AD7793_CH_AIN3P_AIN3M   2 /* AIN3(+) - AIN3(-) */
  94#define AD7793_CH_AIN1M_AIN1M   3 /* AIN1(-) - AIN1(-) */
  95#define AD7793_CH_TEMP          6 /* Temp Sensor */
  96#define AD7793_CH_AVDD_MONITOR  7 /* AVDD Monitor */
  97
  98#define AD7795_CH_AIN4P_AIN4M   4 /* AIN4(+) - AIN4(-) */
  99#define AD7795_CH_AIN5P_AIN5M   5 /* AIN5(+) - AIN5(-) */
 100#define AD7795_CH_AIN6P_AIN6M   6 /* AIN6(+) - AIN6(-) */
 101#define AD7795_CH_AIN1M_AIN1M   8 /* AIN1(-) - AIN1(-) */
 102
 103/* ID Register Bit Designations (AD7793_REG_ID) */
 104#define AD7785_ID               0x3
 105#define AD7792_ID               0xA
 106#define AD7793_ID               0xB
 107#define AD7794_ID               0xF
 108#define AD7795_ID               0xF
 109#define AD7796_ID               0xA
 110#define AD7797_ID               0xB
 111#define AD7798_ID               0x8
 112#define AD7799_ID               0x9
 113#define AD7793_ID_MASK          0xF
 114
 115/* IO (Excitation Current Sources) Register Bit Designations (AD7793_REG_IO) */
 116#define AD7793_IO_IEXC1_IOUT1_IEXC2_IOUT2       0 /* IEXC1 connect to IOUT1,
 117                                                   * IEXC2 connect to IOUT2 */
 118#define AD7793_IO_IEXC1_IOUT2_IEXC2_IOUT1       1 /* IEXC1 connect to IOUT2,
 119                                                   * IEXC2 connect to IOUT1 */
 120#define AD7793_IO_IEXC1_IEXC2_IOUT1             2 /* Both current sources
 121                                                   * IEXC1,2 connect to IOUT1 */
 122#define AD7793_IO_IEXC1_IEXC2_IOUT2             3 /* Both current sources
 123                                                   * IEXC1,2 connect to IOUT2 */
 124
 125#define AD7793_IO_IXCEN_10uA    (1 << 0) /* Excitation Current 10uA */
 126#define AD7793_IO_IXCEN_210uA   (2 << 0) /* Excitation Current 210uA */
 127#define AD7793_IO_IXCEN_1mA     (3 << 0) /* Excitation Current 1mA */
 128
 129/* NOTE:
 130 * The AD7792/AD7793 features a dual use data out ready DOUT/RDY output.
 131 * In order to avoid contentions on the SPI bus, it's therefore necessary
 132 * to use spi bus locking.
 133 *
 134 * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
 135 */
 136
 137#define AD7793_FLAG_HAS_CLKSEL          BIT(0)
 138#define AD7793_FLAG_HAS_REFSEL          BIT(1)
 139#define AD7793_FLAG_HAS_VBIAS           BIT(2)
 140#define AD7793_HAS_EXITATION_CURRENT    BIT(3)
 141#define AD7793_FLAG_HAS_GAIN            BIT(4)
 142#define AD7793_FLAG_HAS_BUFFER          BIT(5)
 143
 144struct ad7793_chip_info {
 145        unsigned int id;
 146        const struct iio_chan_spec *channels;
 147        unsigned int num_channels;
 148        unsigned int flags;
 149
 150        const struct iio_info *iio_info;
 151        const u16 *sample_freq_avail;
 152};
 153
 154struct ad7793_state {
 155        const struct ad7793_chip_info   *chip_info;
 156        struct regulator                *reg;
 157        u16                             int_vref_mv;
 158        u16                             mode;
 159        u16                             conf;
 160        u32                             scale_avail[8][2];
 161
 162        struct ad_sigma_delta           sd;
 163
 164};
 165
 166enum ad7793_supported_device_ids {
 167        ID_AD7785,
 168        ID_AD7792,
 169        ID_AD7793,
 170        ID_AD7794,
 171        ID_AD7795,
 172        ID_AD7796,
 173        ID_AD7797,
 174        ID_AD7798,
 175        ID_AD7799,
 176};
 177
 178static struct ad7793_state *ad_sigma_delta_to_ad7793(struct ad_sigma_delta *sd)
 179{
 180        return container_of(sd, struct ad7793_state, sd);
 181}
 182
 183static int ad7793_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
 184{
 185        struct ad7793_state *st = ad_sigma_delta_to_ad7793(sd);
 186
 187        st->conf &= ~AD7793_CONF_CHAN_MASK;
 188        st->conf |= AD7793_CONF_CHAN(channel);
 189
 190        return ad_sd_write_reg(&st->sd, AD7793_REG_CONF, 2, st->conf);
 191}
 192
 193static int ad7793_set_mode(struct ad_sigma_delta *sd,
 194                           enum ad_sigma_delta_mode mode)
 195{
 196        struct ad7793_state *st = ad_sigma_delta_to_ad7793(sd);
 197
 198        st->mode &= ~AD7793_MODE_SEL_MASK;
 199        st->mode |= AD7793_MODE_SEL(mode);
 200
 201        return ad_sd_write_reg(&st->sd, AD7793_REG_MODE, 2, st->mode);
 202}
 203
 204static const struct ad_sigma_delta_info ad7793_sigma_delta_info = {
 205        .set_channel = ad7793_set_channel,
 206        .set_mode = ad7793_set_mode,
 207        .has_registers = true,
 208        .addr_shift = 3,
 209        .read_mask = BIT(6),
 210};
 211
 212static const struct ad_sd_calib_data ad7793_calib_arr[6] = {
 213        {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN1P_AIN1M},
 214        {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN1P_AIN1M},
 215        {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN2P_AIN2M},
 216        {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN2P_AIN2M},
 217        {AD7793_MODE_CAL_INT_ZERO, AD7793_CH_AIN3P_AIN3M},
 218        {AD7793_MODE_CAL_INT_FULL, AD7793_CH_AIN3P_AIN3M}
 219};
 220
 221static int ad7793_calibrate_all(struct ad7793_state *st)
 222{
 223        return ad_sd_calibrate_all(&st->sd, ad7793_calib_arr,
 224                                   ARRAY_SIZE(ad7793_calib_arr));
 225}
 226
 227static int ad7793_check_platform_data(struct ad7793_state *st,
 228        const struct ad7793_platform_data *pdata)
 229{
 230        if ((pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT1 ||
 231                pdata->current_source_direction == AD7793_IEXEC1_IEXEC2_IOUT2) &&
 232                ((pdata->exitation_current != AD7793_IX_10uA) &&
 233                (pdata->exitation_current != AD7793_IX_210uA)))
 234                return -EINVAL;
 235
 236        if (!(st->chip_info->flags & AD7793_FLAG_HAS_CLKSEL) &&
 237                pdata->clock_src != AD7793_CLK_SRC_INT)
 238                return -EINVAL;
 239
 240        if (!(st->chip_info->flags & AD7793_FLAG_HAS_REFSEL) &&
 241                pdata->refsel != AD7793_REFSEL_REFIN1)
 242                return -EINVAL;
 243
 244        if (!(st->chip_info->flags & AD7793_FLAG_HAS_VBIAS) &&
 245                pdata->bias_voltage != AD7793_BIAS_VOLTAGE_DISABLED)
 246                return -EINVAL;
 247
 248        if (!(st->chip_info->flags & AD7793_HAS_EXITATION_CURRENT) &&
 249                pdata->exitation_current != AD7793_IX_DISABLED)
 250                return -EINVAL;
 251
 252        return 0;
 253}
 254
 255static int ad7793_setup(struct iio_dev *indio_dev,
 256        const struct ad7793_platform_data *pdata,
 257        unsigned int vref_mv)
 258{
 259        struct ad7793_state *st = iio_priv(indio_dev);
 260        int i, ret = -1;
 261        unsigned long long scale_uv;
 262        u32 id;
 263
 264        ret = ad7793_check_platform_data(st, pdata);
 265        if (ret)
 266                return ret;
 267
 268        /* reset the serial interface */
 269        ret = spi_write(st->sd.spi, (u8 *)&ret, sizeof(ret));
 270        if (ret < 0)
 271                goto out;
 272        usleep_range(500, 2000); /* Wait for at least 500us */
 273
 274        /* write/read test for device presence */
 275        ret = ad_sd_read_reg(&st->sd, AD7793_REG_ID, 1, &id);
 276        if (ret)
 277                goto out;
 278
 279        id &= AD7793_ID_MASK;
 280
 281        if (id != st->chip_info->id) {
 282                dev_err(&st->sd.spi->dev, "device ID query failed\n");
 283                goto out;
 284        }
 285
 286        st->mode = AD7793_MODE_RATE(1);
 287        st->conf = 0;
 288
 289        if (st->chip_info->flags & AD7793_FLAG_HAS_CLKSEL)
 290                st->mode |= AD7793_MODE_CLKSRC(pdata->clock_src);
 291        if (st->chip_info->flags & AD7793_FLAG_HAS_REFSEL)
 292                st->conf |= AD7793_CONF_REFSEL(pdata->refsel);
 293        if (st->chip_info->flags & AD7793_FLAG_HAS_VBIAS)
 294                st->conf |= AD7793_CONF_VBIAS(pdata->bias_voltage);
 295        if (pdata->buffered || !(st->chip_info->flags & AD7793_FLAG_HAS_BUFFER))
 296                st->conf |= AD7793_CONF_BUF;
 297        if (pdata->boost_enable &&
 298                (st->chip_info->flags & AD7793_FLAG_HAS_VBIAS))
 299                st->conf |= AD7793_CONF_BOOST;
 300        if (pdata->burnout_current)
 301                st->conf |= AD7793_CONF_BO_EN;
 302        if (pdata->unipolar)
 303                st->conf |= AD7793_CONF_UNIPOLAR;
 304
 305        if (!(st->chip_info->flags & AD7793_FLAG_HAS_GAIN))
 306                st->conf |= AD7793_CONF_GAIN(7);
 307
 308        ret = ad7793_set_mode(&st->sd, AD_SD_MODE_IDLE);
 309        if (ret)
 310                goto out;
 311
 312        ret = ad7793_set_channel(&st->sd, 0);
 313        if (ret)
 314                goto out;
 315
 316        if (st->chip_info->flags & AD7793_HAS_EXITATION_CURRENT) {
 317                ret = ad_sd_write_reg(&st->sd, AD7793_REG_IO, 1,
 318                                pdata->exitation_current |
 319                                (pdata->current_source_direction << 2));
 320                if (ret)
 321                        goto out;
 322        }
 323
 324        ret = ad7793_calibrate_all(st);
 325        if (ret)
 326                goto out;
 327
 328        /* Populate available ADC input ranges */
 329        for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
 330                scale_uv = ((u64)vref_mv * 100000000)
 331                        >> (st->chip_info->channels[0].scan_type.realbits -
 332                        (!!(st->conf & AD7793_CONF_UNIPOLAR) ? 0 : 1));
 333                scale_uv >>= i;
 334
 335                st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
 336                st->scale_avail[i][0] = scale_uv;
 337        }
 338
 339        return 0;
 340out:
 341        dev_err(&st->sd.spi->dev, "setup failed\n");
 342        return ret;
 343}
 344
 345static const u16 ad7793_sample_freq_avail[16] = {0, 470, 242, 123, 62, 50, 39,
 346                                        33, 19, 17, 16, 12, 10, 8, 6, 4};
 347
 348static const u16 ad7797_sample_freq_avail[16] = {0, 0, 0, 123, 62, 50, 0,
 349                                        33, 0, 17, 16, 12, 10, 8, 6, 4};
 350
 351static ssize_t ad7793_read_frequency(struct device *dev,
 352                struct device_attribute *attr,
 353                char *buf)
 354{
 355        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 356        struct ad7793_state *st = iio_priv(indio_dev);
 357
 358        return sprintf(buf, "%d\n",
 359               st->chip_info->sample_freq_avail[AD7793_MODE_RATE(st->mode)]);
 360}
 361
 362static ssize_t ad7793_write_frequency(struct device *dev,
 363                struct device_attribute *attr,
 364                const char *buf,
 365                size_t len)
 366{
 367        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 368        struct ad7793_state *st = iio_priv(indio_dev);
 369        long lval;
 370        int i, ret;
 371
 372        mutex_lock(&indio_dev->mlock);
 373        if (iio_buffer_enabled(indio_dev)) {
 374                mutex_unlock(&indio_dev->mlock);
 375                return -EBUSY;
 376        }
 377        mutex_unlock(&indio_dev->mlock);
 378
 379        ret = kstrtol(buf, 10, &lval);
 380        if (ret)
 381                return ret;
 382
 383        if (lval == 0)
 384                return -EINVAL;
 385
 386        ret = -EINVAL;
 387
 388        for (i = 0; i < 16; i++)
 389                if (lval == st->chip_info->sample_freq_avail[i]) {
 390                        mutex_lock(&indio_dev->mlock);
 391                        st->mode &= ~AD7793_MODE_RATE(-1);
 392                        st->mode |= AD7793_MODE_RATE(i);
 393                        ad_sd_write_reg(&st->sd, AD7793_REG_MODE,
 394                                         sizeof(st->mode), st->mode);
 395                        mutex_unlock(&indio_dev->mlock);
 396                        ret = 0;
 397                }
 398
 399        return ret ? ret : len;
 400}
 401
 402static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
 403                ad7793_read_frequency,
 404                ad7793_write_frequency);
 405
 406static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 407        "470 242 123 62 50 39 33 19 17 16 12 10 8 6 4");
 408
 409static IIO_CONST_ATTR_NAMED(sampling_frequency_available_ad7797,
 410        sampling_frequency_available, "123 62 50 33 17 16 12 10 8 6 4");
 411
 412static ssize_t ad7793_show_scale_available(struct device *dev,
 413                        struct device_attribute *attr, char *buf)
 414{
 415        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 416        struct ad7793_state *st = iio_priv(indio_dev);
 417        int i, len = 0;
 418
 419        for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
 420                len += sprintf(buf + len, "%d.%09u ", st->scale_avail[i][0],
 421                               st->scale_avail[i][1]);
 422
 423        len += sprintf(buf + len, "\n");
 424
 425        return len;
 426}
 427
 428static IIO_DEVICE_ATTR_NAMED(in_m_in_scale_available,
 429                in_voltage-voltage_scale_available, S_IRUGO,
 430                ad7793_show_scale_available, NULL, 0);
 431
 432static struct attribute *ad7793_attributes[] = {
 433        &iio_dev_attr_sampling_frequency.dev_attr.attr,
 434        &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 435        &iio_dev_attr_in_m_in_scale_available.dev_attr.attr,
 436        NULL
 437};
 438
 439static const struct attribute_group ad7793_attribute_group = {
 440        .attrs = ad7793_attributes,
 441};
 442
 443static struct attribute *ad7797_attributes[] = {
 444        &iio_dev_attr_sampling_frequency.dev_attr.attr,
 445        &iio_const_attr_sampling_frequency_available_ad7797.dev_attr.attr,
 446        NULL
 447};
 448
 449static const struct attribute_group ad7797_attribute_group = {
 450        .attrs = ad7797_attributes,
 451};
 452
 453static int ad7793_read_raw(struct iio_dev *indio_dev,
 454                           struct iio_chan_spec const *chan,
 455                           int *val,
 456                           int *val2,
 457                           long m)
 458{
 459        struct ad7793_state *st = iio_priv(indio_dev);
 460        int ret;
 461        unsigned long long scale_uv;
 462        bool unipolar = !!(st->conf & AD7793_CONF_UNIPOLAR);
 463
 464        switch (m) {
 465        case IIO_CHAN_INFO_RAW:
 466                ret = ad_sigma_delta_single_conversion(indio_dev, chan, val);
 467                if (ret < 0)
 468                        return ret;
 469
 470                return IIO_VAL_INT;
 471
 472        case IIO_CHAN_INFO_SCALE:
 473                switch (chan->type) {
 474                case IIO_VOLTAGE:
 475                        if (chan->differential) {
 476                                *val = st->
 477                                        scale_avail[(st->conf >> 8) & 0x7][0];
 478                                *val2 = st->
 479                                        scale_avail[(st->conf >> 8) & 0x7][1];
 480                                return IIO_VAL_INT_PLUS_NANO;
 481                        }
 482                        /* 1170mV / 2^23 * 6 */
 483                        scale_uv = (1170ULL * 1000000000ULL * 6ULL);
 484                        break;
 485                case IIO_TEMP:
 486                                /* 1170mV / 0.81 mV/C / 2^23 */
 487                                scale_uv = 1444444444444444ULL;
 488                        break;
 489                default:
 490                        return -EINVAL;
 491                }
 492
 493                scale_uv >>= (chan->scan_type.realbits - (unipolar ? 0 : 1));
 494                *val = 0;
 495                *val2 = scale_uv;
 496                return IIO_VAL_INT_PLUS_NANO;
 497        case IIO_CHAN_INFO_OFFSET:
 498                if (!unipolar)
 499                        *val = -(1 << (chan->scan_type.realbits - 1));
 500                else
 501                        *val = 0;
 502
 503                /* Kelvin to Celsius */
 504                if (chan->type == IIO_TEMP) {
 505                        unsigned long long offset;
 506                        unsigned int shift;
 507
 508                        shift = chan->scan_type.realbits - (unipolar ? 0 : 1);
 509                        offset = 273ULL << shift;
 510                        do_div(offset, 1444);
 511                        *val -= offset;
 512                }
 513                return IIO_VAL_INT;
 514        }
 515        return -EINVAL;
 516}
 517
 518static int ad7793_write_raw(struct iio_dev *indio_dev,
 519                               struct iio_chan_spec const *chan,
 520                               int val,
 521                               int val2,
 522                               long mask)
 523{
 524        struct ad7793_state *st = iio_priv(indio_dev);
 525        int ret, i;
 526        unsigned int tmp;
 527
 528        mutex_lock(&indio_dev->mlock);
 529        if (iio_buffer_enabled(indio_dev)) {
 530                mutex_unlock(&indio_dev->mlock);
 531                return -EBUSY;
 532        }
 533
 534        switch (mask) {
 535        case IIO_CHAN_INFO_SCALE:
 536                ret = -EINVAL;
 537                for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
 538                        if (val2 == st->scale_avail[i][1]) {
 539                                ret = 0;
 540                                tmp = st->conf;
 541                                st->conf &= ~AD7793_CONF_GAIN(-1);
 542                                st->conf |= AD7793_CONF_GAIN(i);
 543
 544                                if (tmp == st->conf)
 545                                        break;
 546
 547                                ad_sd_write_reg(&st->sd, AD7793_REG_CONF,
 548                                                sizeof(st->conf), st->conf);
 549                                ad7793_calibrate_all(st);
 550                                break;
 551                        }
 552                break;
 553        default:
 554                ret = -EINVAL;
 555        }
 556
 557        mutex_unlock(&indio_dev->mlock);
 558        return ret;
 559}
 560
 561static int ad7793_write_raw_get_fmt(struct iio_dev *indio_dev,
 562                               struct iio_chan_spec const *chan,
 563                               long mask)
 564{
 565        return IIO_VAL_INT_PLUS_NANO;
 566}
 567
 568static const struct iio_info ad7793_info = {
 569        .read_raw = &ad7793_read_raw,
 570        .write_raw = &ad7793_write_raw,
 571        .write_raw_get_fmt = &ad7793_write_raw_get_fmt,
 572        .attrs = &ad7793_attribute_group,
 573        .validate_trigger = ad_sd_validate_trigger,
 574        .driver_module = THIS_MODULE,
 575};
 576
 577static const struct iio_info ad7797_info = {
 578        .read_raw = &ad7793_read_raw,
 579        .write_raw = &ad7793_write_raw,
 580        .write_raw_get_fmt = &ad7793_write_raw_get_fmt,
 581        .attrs = &ad7793_attribute_group,
 582        .validate_trigger = ad_sd_validate_trigger,
 583        .driver_module = THIS_MODULE,
 584};
 585
 586#define DECLARE_AD7793_CHANNELS(_name, _b, _sb, _s) \
 587const struct iio_chan_spec _name##_channels[] = { \
 588        AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), (_s)), \
 589        AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), (_s)), \
 590        AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), (_s)), \
 591        AD_SD_SHORTED_CHANNEL(3, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), (_s)), \
 592        AD_SD_TEMP_CHANNEL(4, AD7793_CH_TEMP, (_b), (_sb), (_s)), \
 593        AD_SD_SUPPLY_CHANNEL(5, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), (_s)), \
 594        IIO_CHAN_SOFT_TIMESTAMP(6), \
 595}
 596
 597#define DECLARE_AD7795_CHANNELS(_name, _b, _sb) \
 598const struct iio_chan_spec _name##_channels[] = { \
 599        AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
 600        AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), 0), \
 601        AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), 0), \
 602        AD_SD_DIFF_CHANNEL(3, 3, 3, AD7795_CH_AIN4P_AIN4M, (_b), (_sb), 0), \
 603        AD_SD_DIFF_CHANNEL(4, 4, 4, AD7795_CH_AIN5P_AIN5M, (_b), (_sb), 0), \
 604        AD_SD_DIFF_CHANNEL(5, 5, 5, AD7795_CH_AIN6P_AIN6M, (_b), (_sb), 0), \
 605        AD_SD_SHORTED_CHANNEL(6, 0, AD7795_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
 606        AD_SD_TEMP_CHANNEL(7, AD7793_CH_TEMP, (_b), (_sb), 0), \
 607        AD_SD_SUPPLY_CHANNEL(8, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
 608        IIO_CHAN_SOFT_TIMESTAMP(9), \
 609}
 610
 611#define DECLARE_AD7797_CHANNELS(_name, _b, _sb) \
 612const struct iio_chan_spec _name##_channels[] = { \
 613        AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
 614        AD_SD_SHORTED_CHANNEL(1, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
 615        AD_SD_TEMP_CHANNEL(2, AD7793_CH_TEMP, (_b), (_sb), 0), \
 616        AD_SD_SUPPLY_CHANNEL(3, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
 617        IIO_CHAN_SOFT_TIMESTAMP(4), \
 618}
 619
 620#define DECLARE_AD7799_CHANNELS(_name, _b, _sb) \
 621const struct iio_chan_spec _name##_channels[] = { \
 622        AD_SD_DIFF_CHANNEL(0, 0, 0, AD7793_CH_AIN1P_AIN1M, (_b), (_sb), 0), \
 623        AD_SD_DIFF_CHANNEL(1, 1, 1, AD7793_CH_AIN2P_AIN2M, (_b), (_sb), 0), \
 624        AD_SD_DIFF_CHANNEL(2, 2, 2, AD7793_CH_AIN3P_AIN3M, (_b), (_sb), 0), \
 625        AD_SD_SHORTED_CHANNEL(3, 0, AD7793_CH_AIN1M_AIN1M, (_b), (_sb), 0), \
 626        AD_SD_SUPPLY_CHANNEL(4, 3, AD7793_CH_AVDD_MONITOR, (_b), (_sb), 0), \
 627        IIO_CHAN_SOFT_TIMESTAMP(5), \
 628}
 629
 630static DECLARE_AD7793_CHANNELS(ad7785, 20, 32, 4);
 631static DECLARE_AD7793_CHANNELS(ad7792, 16, 32, 0);
 632static DECLARE_AD7793_CHANNELS(ad7793, 24, 32, 0);
 633static DECLARE_AD7795_CHANNELS(ad7794, 16, 32);
 634static DECLARE_AD7795_CHANNELS(ad7795, 24, 32);
 635static DECLARE_AD7797_CHANNELS(ad7796, 16, 16);
 636static DECLARE_AD7797_CHANNELS(ad7797, 24, 32);
 637static DECLARE_AD7799_CHANNELS(ad7798, 16, 16);
 638static DECLARE_AD7799_CHANNELS(ad7799, 24, 32);
 639
 640static const struct ad7793_chip_info ad7793_chip_info_tbl[] = {
 641        [ID_AD7785] = {
 642                .id = AD7785_ID,
 643                .channels = ad7785_channels,
 644                .num_channels = ARRAY_SIZE(ad7785_channels),
 645                .iio_info = &ad7793_info,
 646                .sample_freq_avail = ad7793_sample_freq_avail,
 647                .flags = AD7793_FLAG_HAS_CLKSEL |
 648                        AD7793_FLAG_HAS_REFSEL |
 649                        AD7793_FLAG_HAS_VBIAS |
 650                        AD7793_HAS_EXITATION_CURRENT |
 651                        AD7793_FLAG_HAS_GAIN |
 652                        AD7793_FLAG_HAS_BUFFER,
 653        },
 654        [ID_AD7792] = {
 655                .id = AD7792_ID,
 656                .channels = ad7792_channels,
 657                .num_channels = ARRAY_SIZE(ad7792_channels),
 658                .iio_info = &ad7793_info,
 659                .sample_freq_avail = ad7793_sample_freq_avail,
 660                .flags = AD7793_FLAG_HAS_CLKSEL |
 661                        AD7793_FLAG_HAS_REFSEL |
 662                        AD7793_FLAG_HAS_VBIAS |
 663                        AD7793_HAS_EXITATION_CURRENT |
 664                        AD7793_FLAG_HAS_GAIN |
 665                        AD7793_FLAG_HAS_BUFFER,
 666        },
 667        [ID_AD7793] = {
 668                .id = AD7793_ID,
 669                .channels = ad7793_channels,
 670                .num_channels = ARRAY_SIZE(ad7793_channels),
 671                .iio_info = &ad7793_info,
 672                .sample_freq_avail = ad7793_sample_freq_avail,
 673                .flags = AD7793_FLAG_HAS_CLKSEL |
 674                        AD7793_FLAG_HAS_REFSEL |
 675                        AD7793_FLAG_HAS_VBIAS |
 676                        AD7793_HAS_EXITATION_CURRENT |
 677                        AD7793_FLAG_HAS_GAIN |
 678                        AD7793_FLAG_HAS_BUFFER,
 679        },
 680        [ID_AD7794] = {
 681                .id = AD7794_ID,
 682                .channels = ad7794_channels,
 683                .num_channels = ARRAY_SIZE(ad7794_channels),
 684                .iio_info = &ad7793_info,
 685                .sample_freq_avail = ad7793_sample_freq_avail,
 686                .flags = AD7793_FLAG_HAS_CLKSEL |
 687                        AD7793_FLAG_HAS_REFSEL |
 688                        AD7793_FLAG_HAS_VBIAS |
 689                        AD7793_HAS_EXITATION_CURRENT |
 690                        AD7793_FLAG_HAS_GAIN |
 691                        AD7793_FLAG_HAS_BUFFER,
 692        },
 693        [ID_AD7795] = {
 694                .id = AD7795_ID,
 695                .channels = ad7795_channels,
 696                .num_channels = ARRAY_SIZE(ad7795_channels),
 697                .iio_info = &ad7793_info,
 698                .sample_freq_avail = ad7793_sample_freq_avail,
 699                .flags = AD7793_FLAG_HAS_CLKSEL |
 700                        AD7793_FLAG_HAS_REFSEL |
 701                        AD7793_FLAG_HAS_VBIAS |
 702                        AD7793_HAS_EXITATION_CURRENT |
 703                        AD7793_FLAG_HAS_GAIN |
 704                        AD7793_FLAG_HAS_BUFFER,
 705        },
 706        [ID_AD7796] = {
 707                .id = AD7796_ID,
 708                .channels = ad7796_channels,
 709                .num_channels = ARRAY_SIZE(ad7796_channels),
 710                .iio_info = &ad7797_info,
 711                .sample_freq_avail = ad7797_sample_freq_avail,
 712                .flags = AD7793_FLAG_HAS_CLKSEL,
 713        },
 714        [ID_AD7797] = {
 715                .id = AD7797_ID,
 716                .channels = ad7797_channels,
 717                .num_channels = ARRAY_SIZE(ad7797_channels),
 718                .iio_info = &ad7797_info,
 719                .sample_freq_avail = ad7797_sample_freq_avail,
 720                .flags = AD7793_FLAG_HAS_CLKSEL,
 721        },
 722        [ID_AD7798] = {
 723                .id = AD7798_ID,
 724                .channels = ad7798_channels,
 725                .num_channels = ARRAY_SIZE(ad7798_channels),
 726                .iio_info = &ad7793_info,
 727                .sample_freq_avail = ad7793_sample_freq_avail,
 728                .flags = AD7793_FLAG_HAS_GAIN |
 729                        AD7793_FLAG_HAS_BUFFER,
 730        },
 731        [ID_AD7799] = {
 732                .id = AD7799_ID,
 733                .channels = ad7799_channels,
 734                .num_channels = ARRAY_SIZE(ad7799_channels),
 735                .iio_info = &ad7793_info,
 736                .sample_freq_avail = ad7793_sample_freq_avail,
 737                .flags = AD7793_FLAG_HAS_GAIN |
 738                        AD7793_FLAG_HAS_BUFFER,
 739        },
 740};
 741
 742static int ad7793_probe(struct spi_device *spi)
 743{
 744        const struct ad7793_platform_data *pdata = spi->dev.platform_data;
 745        struct ad7793_state *st;
 746        struct iio_dev *indio_dev;
 747        int ret, vref_mv = 0;
 748
 749        if (!pdata) {
 750                dev_err(&spi->dev, "no platform data?\n");
 751                return -ENODEV;
 752        }
 753
 754        if (!spi->irq) {
 755                dev_err(&spi->dev, "no IRQ?\n");
 756                return -ENODEV;
 757        }
 758
 759        indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 760        if (indio_dev == NULL)
 761                return -ENOMEM;
 762
 763        st = iio_priv(indio_dev);
 764
 765        ad_sd_init(&st->sd, indio_dev, spi, &ad7793_sigma_delta_info);
 766
 767        if (pdata->refsel != AD7793_REFSEL_INTERNAL) {
 768                st->reg = devm_regulator_get(&spi->dev, "refin");
 769                if (IS_ERR(st->reg))
 770                        return PTR_ERR(st->reg);
 771
 772                ret = regulator_enable(st->reg);
 773                if (ret)
 774                        return ret;
 775
 776                vref_mv = regulator_get_voltage(st->reg);
 777                if (vref_mv < 0) {
 778                        ret = vref_mv;
 779                        goto error_disable_reg;
 780                }
 781
 782                vref_mv /= 1000;
 783        } else {
 784                vref_mv = 1170; /* Build-in ref */
 785        }
 786
 787        st->chip_info =
 788                &ad7793_chip_info_tbl[spi_get_device_id(spi)->driver_data];
 789
 790        spi_set_drvdata(spi, indio_dev);
 791
 792        indio_dev->dev.parent = &spi->dev;
 793        indio_dev->name = spi_get_device_id(spi)->name;
 794        indio_dev->modes = INDIO_DIRECT_MODE;
 795        indio_dev->channels = st->chip_info->channels;
 796        indio_dev->num_channels = st->chip_info->num_channels;
 797        indio_dev->info = st->chip_info->iio_info;
 798
 799        ret = ad_sd_setup_buffer_and_trigger(indio_dev);
 800        if (ret)
 801                goto error_disable_reg;
 802
 803        ret = ad7793_setup(indio_dev, pdata, vref_mv);
 804        if (ret)
 805                goto error_remove_trigger;
 806
 807        ret = iio_device_register(indio_dev);
 808        if (ret)
 809                goto error_remove_trigger;
 810
 811        return 0;
 812
 813error_remove_trigger:
 814        ad_sd_cleanup_buffer_and_trigger(indio_dev);
 815error_disable_reg:
 816        if (pdata->refsel != AD7793_REFSEL_INTERNAL)
 817                regulator_disable(st->reg);
 818
 819        return ret;
 820}
 821
 822static int ad7793_remove(struct spi_device *spi)
 823{
 824        const struct ad7793_platform_data *pdata = spi->dev.platform_data;
 825        struct iio_dev *indio_dev = spi_get_drvdata(spi);
 826        struct ad7793_state *st = iio_priv(indio_dev);
 827
 828        iio_device_unregister(indio_dev);
 829        ad_sd_cleanup_buffer_and_trigger(indio_dev);
 830
 831        if (pdata->refsel != AD7793_REFSEL_INTERNAL)
 832                regulator_disable(st->reg);
 833
 834        return 0;
 835}
 836
 837static const struct spi_device_id ad7793_id[] = {
 838        {"ad7785", ID_AD7785},
 839        {"ad7792", ID_AD7792},
 840        {"ad7793", ID_AD7793},
 841        {"ad7794", ID_AD7794},
 842        {"ad7795", ID_AD7795},
 843        {"ad7796", ID_AD7796},
 844        {"ad7797", ID_AD7797},
 845        {"ad7798", ID_AD7798},
 846        {"ad7799", ID_AD7799},
 847        {}
 848};
 849MODULE_DEVICE_TABLE(spi, ad7793_id);
 850
 851static struct spi_driver ad7793_driver = {
 852        .driver = {
 853                .name   = "ad7793",
 854        },
 855        .probe          = ad7793_probe,
 856        .remove         = ad7793_remove,
 857        .id_table       = ad7793_id,
 858};
 859module_spi_driver(ad7793_driver);
 860
 861MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 862MODULE_DESCRIPTION("Analog Devices AD7793 and similar ADCs");
 863MODULE_LICENSE("GPL v2");
 864