linux/drivers/staging/iio/frequency/ad9834.c
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   1/*
   2 * AD9833/AD9834/AD9837/AD9838 SPI DDS driver
   3 *
   4 * Copyright 2010-2011 Analog Devices Inc.
   5 *
   6 * Licensed under the GPL-2.
   7 */
   8
   9#include <linux/interrupt.h>
  10#include <linux/workqueue.h>
  11#include <linux/device.h>
  12#include <linux/kernel.h>
  13#include <linux/slab.h>
  14#include <linux/sysfs.h>
  15#include <linux/list.h>
  16#include <linux/spi/spi.h>
  17#include <linux/regulator/consumer.h>
  18#include <linux/err.h>
  19#include <linux/module.h>
  20#include <asm/div64.h>
  21
  22#include <linux/iio/iio.h>
  23#include <linux/iio/sysfs.h>
  24#include "dds.h"
  25
  26#include "ad9834.h"
  27
  28/* Registers */
  29
  30#define AD9834_REG_CMD          0
  31#define AD9834_REG_FREQ0        BIT(14)
  32#define AD9834_REG_FREQ1        BIT(15)
  33#define AD9834_REG_PHASE0       (BIT(15) | BIT(14))
  34#define AD9834_REG_PHASE1       (BIT(15) | BIT(14) | BIT(13))
  35
  36/* Command Control Bits */
  37
  38#define AD9834_B28              BIT(13)
  39#define AD9834_HLB              BIT(12)
  40#define AD9834_FSEL             BIT(11)
  41#define AD9834_PSEL             BIT(10)
  42#define AD9834_PIN_SW           BIT(9)
  43#define AD9834_RESET            BIT(8)
  44#define AD9834_SLEEP1           BIT(7)
  45#define AD9834_SLEEP12          BIT(6)
  46#define AD9834_OPBITEN          BIT(5)
  47#define AD9834_SIGN_PIB         BIT(4)
  48#define AD9834_DIV2             BIT(3)
  49#define AD9834_MODE             BIT(1)
  50
  51#define AD9834_FREQ_BITS        28
  52#define AD9834_PHASE_BITS       12
  53
  54#define RES_MASK(bits)  (BIT(bits) - 1)
  55
  56/**
  57 * struct ad9834_state - driver instance specific data
  58 * @spi:                spi_device
  59 * @reg:                supply regulator
  60 * @mclk:               external master clock
  61 * @control:            cached control word
  62 * @xfer:               default spi transfer
  63 * @msg:                default spi message
  64 * @freq_xfer:          tuning word spi transfer
  65 * @freq_msg:           tuning word spi message
  66 * @lock:               protect sensor state
  67 * @data:               spi transmit buffer
  68 * @freq_data:          tuning word spi transmit buffer
  69 */
  70
  71struct ad9834_state {
  72        struct spi_device               *spi;
  73        struct regulator                *reg;
  74        unsigned int                    mclk;
  75        unsigned short                  control;
  76        unsigned short                  devid;
  77        struct spi_transfer             xfer;
  78        struct spi_message              msg;
  79        struct spi_transfer             freq_xfer[2];
  80        struct spi_message              freq_msg;
  81        struct mutex                    lock;   /* protect sensor state */
  82
  83        /*
  84         * DMA (thus cache coherency maintenance) requires the
  85         * transfer buffers to live in their own cache lines.
  86         */
  87        __be16                          data ____cacheline_aligned;
  88        __be16                          freq_data[2];
  89};
  90
  91/**
  92 * ad9834_supported_device_ids:
  93 */
  94
  95enum ad9834_supported_device_ids {
  96        ID_AD9833,
  97        ID_AD9834,
  98        ID_AD9837,
  99        ID_AD9838,
 100};
 101
 102static unsigned int ad9834_calc_freqreg(unsigned long mclk, unsigned long fout)
 103{
 104        unsigned long long freqreg = (u64)fout * (u64)BIT(AD9834_FREQ_BITS);
 105
 106        do_div(freqreg, mclk);
 107        return freqreg;
 108}
 109
 110static int ad9834_write_frequency(struct ad9834_state *st,
 111                                  unsigned long addr, unsigned long fout)
 112{
 113        unsigned long regval;
 114
 115        if (fout > (st->mclk / 2))
 116                return -EINVAL;
 117
 118        regval = ad9834_calc_freqreg(st->mclk, fout);
 119
 120        st->freq_data[0] = cpu_to_be16(addr | (regval &
 121                                       RES_MASK(AD9834_FREQ_BITS / 2)));
 122        st->freq_data[1] = cpu_to_be16(addr | ((regval >>
 123                                       (AD9834_FREQ_BITS / 2)) &
 124                                       RES_MASK(AD9834_FREQ_BITS / 2)));
 125
 126        return spi_sync(st->spi, &st->freq_msg);
 127}
 128
 129static int ad9834_write_phase(struct ad9834_state *st,
 130                              unsigned long addr, unsigned long phase)
 131{
 132        if (phase > BIT(AD9834_PHASE_BITS))
 133                return -EINVAL;
 134        st->data = cpu_to_be16(addr | phase);
 135
 136        return spi_sync(st->spi, &st->msg);
 137}
 138
 139static ssize_t ad9834_write(struct device *dev,
 140                            struct device_attribute *attr,
 141                            const char *buf,
 142                            size_t len)
 143{
 144        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 145        struct ad9834_state *st = iio_priv(indio_dev);
 146        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 147        int ret;
 148        unsigned long val;
 149
 150        ret = kstrtoul(buf, 10, &val);
 151        if (ret)
 152                return ret;
 153
 154        mutex_lock(&st->lock);
 155        switch ((u32)this_attr->address) {
 156        case AD9834_REG_FREQ0:
 157        case AD9834_REG_FREQ1:
 158                ret = ad9834_write_frequency(st, this_attr->address, val);
 159                break;
 160        case AD9834_REG_PHASE0:
 161        case AD9834_REG_PHASE1:
 162                ret = ad9834_write_phase(st, this_attr->address, val);
 163                break;
 164        case AD9834_OPBITEN:
 165                if (st->control & AD9834_MODE) {
 166                        ret = -EINVAL;  /* AD9843 reserved mode */
 167                        break;
 168                }
 169
 170                if (val)
 171                        st->control |= AD9834_OPBITEN;
 172                else
 173                        st->control &= ~AD9834_OPBITEN;
 174
 175                st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 176                ret = spi_sync(st->spi, &st->msg);
 177                break;
 178        case AD9834_PIN_SW:
 179                if (val)
 180                        st->control |= AD9834_PIN_SW;
 181                else
 182                        st->control &= ~AD9834_PIN_SW;
 183                st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 184                ret = spi_sync(st->spi, &st->msg);
 185                break;
 186        case AD9834_FSEL:
 187        case AD9834_PSEL:
 188                if (!val) {
 189                        st->control &= ~(this_attr->address | AD9834_PIN_SW);
 190                } else if (val == 1) {
 191                        st->control |= this_attr->address;
 192                        st->control &= ~AD9834_PIN_SW;
 193                } else {
 194                        ret = -EINVAL;
 195                        break;
 196                }
 197                st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 198                ret = spi_sync(st->spi, &st->msg);
 199                break;
 200        case AD9834_RESET:
 201                if (val)
 202                        st->control &= ~AD9834_RESET;
 203                else
 204                        st->control |= AD9834_RESET;
 205
 206                st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 207                ret = spi_sync(st->spi, &st->msg);
 208                break;
 209        default:
 210                ret = -ENODEV;
 211        }
 212        mutex_unlock(&st->lock);
 213
 214        return ret ? ret : len;
 215}
 216
 217static ssize_t ad9834_store_wavetype(struct device *dev,
 218                                     struct device_attribute *attr,
 219                                     const char *buf,
 220                                     size_t len)
 221{
 222        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 223        struct ad9834_state *st = iio_priv(indio_dev);
 224        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 225        int ret = 0;
 226        bool is_ad9833_7 = (st->devid == ID_AD9833) || (st->devid == ID_AD9837);
 227
 228        mutex_lock(&st->lock);
 229
 230        switch ((u32)this_attr->address) {
 231        case 0:
 232                if (sysfs_streq(buf, "sine")) {
 233                        st->control &= ~AD9834_MODE;
 234                        if (is_ad9833_7)
 235                                st->control &= ~AD9834_OPBITEN;
 236                } else if (sysfs_streq(buf, "triangle")) {
 237                        if (is_ad9833_7) {
 238                                st->control &= ~AD9834_OPBITEN;
 239                                st->control |= AD9834_MODE;
 240                        } else if (st->control & AD9834_OPBITEN) {
 241                                ret = -EINVAL;  /* AD9843 reserved mode */
 242                        } else {
 243                                st->control |= AD9834_MODE;
 244                        }
 245                } else if (is_ad9833_7 && sysfs_streq(buf, "square")) {
 246                        st->control &= ~AD9834_MODE;
 247                        st->control |= AD9834_OPBITEN;
 248                } else {
 249                        ret = -EINVAL;
 250                }
 251
 252                break;
 253        case 1:
 254                if (sysfs_streq(buf, "square") &&
 255                    !(st->control & AD9834_MODE)) {
 256                        st->control &= ~AD9834_MODE;
 257                        st->control |= AD9834_OPBITEN;
 258                } else {
 259                        ret = -EINVAL;
 260                }
 261                break;
 262        default:
 263                ret = -EINVAL;
 264                break;
 265        }
 266
 267        if (!ret) {
 268                st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 269                ret = spi_sync(st->spi, &st->msg);
 270        }
 271        mutex_unlock(&st->lock);
 272
 273        return ret ? ret : len;
 274}
 275
 276static
 277ssize_t ad9834_show_out0_wavetype_available(struct device *dev,
 278                                            struct device_attribute *attr,
 279                                            char *buf)
 280{
 281        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 282        struct ad9834_state *st = iio_priv(indio_dev);
 283        char *str;
 284
 285        if ((st->devid == ID_AD9833) || (st->devid == ID_AD9837))
 286                str = "sine triangle square";
 287        else if (st->control & AD9834_OPBITEN)
 288                str = "sine";
 289        else
 290                str = "sine triangle";
 291
 292        return sprintf(buf, "%s\n", str);
 293}
 294
 295static IIO_DEVICE_ATTR(out_altvoltage0_out0_wavetype_available, 0444,
 296                       ad9834_show_out0_wavetype_available, NULL, 0);
 297
 298static
 299ssize_t ad9834_show_out1_wavetype_available(struct device *dev,
 300                                            struct device_attribute *attr,
 301                                            char *buf)
 302{
 303        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 304        struct ad9834_state *st = iio_priv(indio_dev);
 305        char *str;
 306
 307        if (st->control & AD9834_MODE)
 308                str = "";
 309        else
 310                str = "square";
 311
 312        return sprintf(buf, "%s\n", str);
 313}
 314
 315static IIO_DEVICE_ATTR(out_altvoltage0_out1_wavetype_available, 0444,
 316                       ad9834_show_out1_wavetype_available, NULL, 0);
 317
 318/**
 319 * see dds.h for further information
 320 */
 321
 322static IIO_DEV_ATTR_FREQ(0, 0, 0200, NULL, ad9834_write, AD9834_REG_FREQ0);
 323static IIO_DEV_ATTR_FREQ(0, 1, 0200, NULL, ad9834_write, AD9834_REG_FREQ1);
 324static IIO_DEV_ATTR_FREQSYMBOL(0, 0200, NULL, ad9834_write, AD9834_FSEL);
 325static IIO_CONST_ATTR_FREQ_SCALE(0, "1"); /* 1Hz */
 326
 327static IIO_DEV_ATTR_PHASE(0, 0, 0200, NULL, ad9834_write, AD9834_REG_PHASE0);
 328static IIO_DEV_ATTR_PHASE(0, 1, 0200, NULL, ad9834_write, AD9834_REG_PHASE1);
 329static IIO_DEV_ATTR_PHASESYMBOL(0, 0200, NULL, ad9834_write, AD9834_PSEL);
 330static IIO_CONST_ATTR_PHASE_SCALE(0, "0.0015339808"); /* 2PI/2^12 rad*/
 331
 332static IIO_DEV_ATTR_PINCONTROL_EN(0, 0200, NULL,
 333        ad9834_write, AD9834_PIN_SW);
 334static IIO_DEV_ATTR_OUT_ENABLE(0, 0200, NULL, ad9834_write, AD9834_RESET);
 335static IIO_DEV_ATTR_OUTY_ENABLE(0, 1, 0200, NULL,
 336        ad9834_write, AD9834_OPBITEN);
 337static IIO_DEV_ATTR_OUT_WAVETYPE(0, 0, ad9834_store_wavetype, 0);
 338static IIO_DEV_ATTR_OUT_WAVETYPE(0, 1, ad9834_store_wavetype, 1);
 339
 340static struct attribute *ad9834_attributes[] = {
 341        &iio_dev_attr_out_altvoltage0_frequency0.dev_attr.attr,
 342        &iio_dev_attr_out_altvoltage0_frequency1.dev_attr.attr,
 343        &iio_const_attr_out_altvoltage0_frequency_scale.dev_attr.attr,
 344        &iio_dev_attr_out_altvoltage0_phase0.dev_attr.attr,
 345        &iio_dev_attr_out_altvoltage0_phase1.dev_attr.attr,
 346        &iio_const_attr_out_altvoltage0_phase_scale.dev_attr.attr,
 347        &iio_dev_attr_out_altvoltage0_pincontrol_en.dev_attr.attr,
 348        &iio_dev_attr_out_altvoltage0_frequencysymbol.dev_attr.attr,
 349        &iio_dev_attr_out_altvoltage0_phasesymbol.dev_attr.attr,
 350        &iio_dev_attr_out_altvoltage0_out_enable.dev_attr.attr,
 351        &iio_dev_attr_out_altvoltage0_out1_enable.dev_attr.attr,
 352        &iio_dev_attr_out_altvoltage0_out0_wavetype.dev_attr.attr,
 353        &iio_dev_attr_out_altvoltage0_out1_wavetype.dev_attr.attr,
 354        &iio_dev_attr_out_altvoltage0_out0_wavetype_available.dev_attr.attr,
 355        &iio_dev_attr_out_altvoltage0_out1_wavetype_available.dev_attr.attr,
 356        NULL,
 357};
 358
 359static struct attribute *ad9833_attributes[] = {
 360        &iio_dev_attr_out_altvoltage0_frequency0.dev_attr.attr,
 361        &iio_dev_attr_out_altvoltage0_frequency1.dev_attr.attr,
 362        &iio_const_attr_out_altvoltage0_frequency_scale.dev_attr.attr,
 363        &iio_dev_attr_out_altvoltage0_phase0.dev_attr.attr,
 364        &iio_dev_attr_out_altvoltage0_phase1.dev_attr.attr,
 365        &iio_const_attr_out_altvoltage0_phase_scale.dev_attr.attr,
 366        &iio_dev_attr_out_altvoltage0_frequencysymbol.dev_attr.attr,
 367        &iio_dev_attr_out_altvoltage0_phasesymbol.dev_attr.attr,
 368        &iio_dev_attr_out_altvoltage0_out_enable.dev_attr.attr,
 369        &iio_dev_attr_out_altvoltage0_out0_wavetype.dev_attr.attr,
 370        &iio_dev_attr_out_altvoltage0_out0_wavetype_available.dev_attr.attr,
 371        NULL,
 372};
 373
 374static const struct attribute_group ad9834_attribute_group = {
 375        .attrs = ad9834_attributes,
 376};
 377
 378static const struct attribute_group ad9833_attribute_group = {
 379        .attrs = ad9833_attributes,
 380};
 381
 382static const struct iio_info ad9834_info = {
 383        .attrs = &ad9834_attribute_group,
 384};
 385
 386static const struct iio_info ad9833_info = {
 387        .attrs = &ad9833_attribute_group,
 388};
 389
 390static int ad9834_probe(struct spi_device *spi)
 391{
 392        struct ad9834_platform_data *pdata = dev_get_platdata(&spi->dev);
 393        struct ad9834_state *st;
 394        struct iio_dev *indio_dev;
 395        struct regulator *reg;
 396        int ret;
 397
 398        if (!pdata) {
 399                dev_dbg(&spi->dev, "no platform data?\n");
 400                return -ENODEV;
 401        }
 402
 403        reg = devm_regulator_get(&spi->dev, "avdd");
 404        if (IS_ERR(reg))
 405                return PTR_ERR(reg);
 406
 407        ret = regulator_enable(reg);
 408        if (ret) {
 409                dev_err(&spi->dev, "Failed to enable specified AVDD supply\n");
 410                return ret;
 411        }
 412
 413        indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 414        if (!indio_dev) {
 415                ret = -ENOMEM;
 416                goto error_disable_reg;
 417        }
 418        spi_set_drvdata(spi, indio_dev);
 419        st = iio_priv(indio_dev);
 420        mutex_init(&st->lock);
 421        st->mclk = pdata->mclk;
 422        st->spi = spi;
 423        st->devid = spi_get_device_id(spi)->driver_data;
 424        st->reg = reg;
 425        indio_dev->dev.parent = &spi->dev;
 426        indio_dev->name = spi_get_device_id(spi)->name;
 427        switch (st->devid) {
 428        case ID_AD9833:
 429        case ID_AD9837:
 430                indio_dev->info = &ad9833_info;
 431                break;
 432        default:
 433                indio_dev->info = &ad9834_info;
 434                break;
 435        }
 436        indio_dev->modes = INDIO_DIRECT_MODE;
 437
 438        /* Setup default messages */
 439
 440        st->xfer.tx_buf = &st->data;
 441        st->xfer.len = 2;
 442
 443        spi_message_init(&st->msg);
 444        spi_message_add_tail(&st->xfer, &st->msg);
 445
 446        st->freq_xfer[0].tx_buf = &st->freq_data[0];
 447        st->freq_xfer[0].len = 2;
 448        st->freq_xfer[0].cs_change = 1;
 449        st->freq_xfer[1].tx_buf = &st->freq_data[1];
 450        st->freq_xfer[1].len = 2;
 451
 452        spi_message_init(&st->freq_msg);
 453        spi_message_add_tail(&st->freq_xfer[0], &st->freq_msg);
 454        spi_message_add_tail(&st->freq_xfer[1], &st->freq_msg);
 455
 456        st->control = AD9834_B28 | AD9834_RESET;
 457
 458        if (!pdata->en_div2)
 459                st->control |= AD9834_DIV2;
 460
 461        if (!pdata->en_signbit_msb_out && (st->devid == ID_AD9834))
 462                st->control |= AD9834_SIGN_PIB;
 463
 464        st->data = cpu_to_be16(AD9834_REG_CMD | st->control);
 465        ret = spi_sync(st->spi, &st->msg);
 466        if (ret) {
 467                dev_err(&spi->dev, "device init failed\n");
 468                goto error_disable_reg;
 469        }
 470
 471        ret = ad9834_write_frequency(st, AD9834_REG_FREQ0, pdata->freq0);
 472        if (ret)
 473                goto error_disable_reg;
 474
 475        ret = ad9834_write_frequency(st, AD9834_REG_FREQ1, pdata->freq1);
 476        if (ret)
 477                goto error_disable_reg;
 478
 479        ret = ad9834_write_phase(st, AD9834_REG_PHASE0, pdata->phase0);
 480        if (ret)
 481                goto error_disable_reg;
 482
 483        ret = ad9834_write_phase(st, AD9834_REG_PHASE1, pdata->phase1);
 484        if (ret)
 485                goto error_disable_reg;
 486
 487        ret = iio_device_register(indio_dev);
 488        if (ret)
 489                goto error_disable_reg;
 490
 491        return 0;
 492
 493error_disable_reg:
 494        regulator_disable(reg);
 495
 496        return ret;
 497}
 498
 499static int ad9834_remove(struct spi_device *spi)
 500{
 501        struct iio_dev *indio_dev = spi_get_drvdata(spi);
 502        struct ad9834_state *st = iio_priv(indio_dev);
 503
 504        iio_device_unregister(indio_dev);
 505        regulator_disable(st->reg);
 506
 507        return 0;
 508}
 509
 510static const struct spi_device_id ad9834_id[] = {
 511        {"ad9833", ID_AD9833},
 512        {"ad9834", ID_AD9834},
 513        {"ad9837", ID_AD9837},
 514        {"ad9838", ID_AD9838},
 515        {}
 516};
 517MODULE_DEVICE_TABLE(spi, ad9834_id);
 518
 519static struct spi_driver ad9834_driver = {
 520        .driver = {
 521                .name   = "ad9834",
 522        },
 523        .probe          = ad9834_probe,
 524        .remove         = ad9834_remove,
 525        .id_table       = ad9834_id,
 526};
 527module_spi_driver(ad9834_driver);
 528
 529MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 530MODULE_DESCRIPTION("Analog Devices AD9833/AD9834/AD9837/AD9838 DDS");
 531MODULE_LICENSE("GPL v2");
 532