drivers/iio/frequency/adf4350.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * ADF4350/ADF4351 SPI Wideband Synthesizer driver
   4  *
   5  * Copyright 2012-2013 Analog Devices Inc.
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/kernel.h>
  10 #include <linux/mod_devicetable.h>
  11 #include <linux/module.h>
  12 #include <linux/property.h>
  13 #include <linux/slab.h>
  14 #include <linux/sysfs.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/regulator/consumer.h>
  17 #include <linux/err.h>
  18 #include <linux/gcd.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <asm/div64.h>
  21 #include <linux/clk.h>
  22
  23 #include <linux/iio/iio.h>
  24 #include <linux/iio/sysfs.h>
  25 #include <linux/iio/frequency/adf4350.h>
  26
  27 enum {
  28         ADF4350_FREQ,
  29         ADF4350_FREQ_REFIN,
  30         ADF4350_FREQ_RESOLUTION,
  31         ADF4350_PWRDOWN,
  32 };
  33
  34 struct adf4350_state {
  35         struct spi_device               *spi;
  36         struct regulator                *reg;
  37         struct gpio_desc                *lock_detect_gpiod;
  38         struct adf4350_platform_data    *pdata;
  39         struct clk                      *clk;
  40         unsigned long                   clkin;
  41         unsigned long                   chspc; /* Channel Spacing */
  42         unsigned long                   fpfd; /* Phase Frequency Detector */
  43         unsigned long                   min_out_freq;
  44         unsigned                        r0_fract;
  45         unsigned                        r0_int;
  46         unsigned                        r1_mod;
  47         unsigned                        r4_rf_div_sel;
  48         unsigned long                   regs[6];
  49         unsigned long                   regs_hw[6];
  50         unsigned long long              freq_req;
  51         /*
  52          * Lock to protect the state of the device from potential concurrent
  53          * writes. The device is configured via a sequence of SPI writes,
  54          * and this lock is meant to prevent the start of another sequence
  55          * before another one has finished.
  56          */
  57         struct mutex                    lock;
  58         /*
  59          * DMA (thus cache coherency maintenance) may require that
  60          * transfer buffers live in their own cache lines.
  61          */
  62         __be32                          val __aligned(IIO_DMA_MINALIGN);
  63 };
  64
  65 static struct adf4350_platform_data default_pdata = {
  66         .channel_spacing = 10000,
  67         .r2_user_settings = ADF4350_REG2_PD_POLARITY_POS |
  68                             ADF4350_REG2_CHARGE_PUMP_CURR_uA(2500),
  69         .r3_user_settings = ADF4350_REG3_12BIT_CLKDIV_MODE(0),
  70         .r4_user_settings = ADF4350_REG4_OUTPUT_PWR(3) |
  71                             ADF4350_REG4_MUTE_TILL_LOCK_EN,
  72 };
  73
  74 static int adf4350_sync_config(struct adf4350_state *st)
  75 {
  76         int ret, i, doublebuf = 0;
  77
  78         for (i = ADF4350_REG5; i >= ADF4350_REG0; i--) {
  79                 if ((st->regs_hw[i] != st->regs[i]) ||
  80                         ((i == ADF4350_REG0) && doublebuf)) {
  81                         switch (i) {
  82                         case ADF4350_REG1:
  83                         case ADF4350_REG4:
  84                                 doublebuf = 1;
  85                                 break;
  86                         }
  87
  88                         st->val  = cpu_to_be32(st->regs[i] | i);
  89                         ret = spi_write(st->spi, &st->val, 4);
  90                         if (ret < 0)
  91                                 return ret;
  92                         st->regs_hw[i] = st->regs[i];
  93                         dev_dbg(&st->spi->dev, "[%d] 0x%X\n",
  94                                 i, (u32)st->regs[i] | i);
  95                 }
  96         }
  97         return 0;
  98 }
  99
 100 static int adf4350_reg_access(struct iio_dev *indio_dev,
 101                               unsigned reg, unsigned writeval,
 102                               unsigned *readval)
 103 {
 104         struct adf4350_state *st = iio_priv(indio_dev);
 105         int ret;
 106
 107         if (reg > ADF4350_REG5)
 108                 return -EINVAL;
 109
 110         mutex_lock(&st->lock);
 111         if (readval == NULL) {
 112                 st->regs[reg] = writeval & ~(BIT(0) | BIT(1) | BIT(2));
 113                 ret = adf4350_sync_config(st);
 114         } else {
 115                 *readval =  st->regs_hw[reg];
 116                 ret = 0;
 117         }
 118         mutex_unlock(&st->lock);
 119
 120         return ret;
 121 }
 122
 123 static int adf4350_tune_r_cnt(struct adf4350_state *st, unsigned short r_cnt)
 124 {
 125         struct adf4350_platform_data *pdata = st->pdata;
 126
 127         do {
 128                 r_cnt++;
 129                 st->fpfd = (st->clkin * (pdata->ref_doubler_en ? 2 : 1)) /
 130                            (r_cnt * (pdata->ref_div2_en ? 2 : 1));
 131         } while (st->fpfd > ADF4350_MAX_FREQ_PFD);
 132
 133         return r_cnt;
 134 }
 135
 136 static int adf4350_set_freq(struct adf4350_state *st, unsigned long long freq)
 137 {
 138         struct adf4350_platform_data *pdata = st->pdata;
 139         u64 tmp;
 140         u32 div_gcd, prescaler, chspc;
 141         u16 mdiv, r_cnt = 0;
 142         u8 band_sel_div;
 143
 144         if (freq > ADF4350_MAX_OUT_FREQ || freq < st->min_out_freq)
 145                 return -EINVAL;
 146
 147         if (freq > ADF4350_MAX_FREQ_45_PRESC) {
 148                 prescaler = ADF4350_REG1_PRESCALER;
 149                 mdiv = 75;
 150         } else {
 151                 prescaler = 0;
 152                 mdiv = 23;
 153         }
 154
 155         st->r4_rf_div_sel = 0;
 156
 157         while (freq < ADF4350_MIN_VCO_FREQ) {
 158                 freq <<= 1;
 159                 st->r4_rf_div_sel++;
 160         }
 161
 162         /*
 163          * Allow a predefined reference division factor
 164          * if not set, compute our own
 165          */
 166         if (pdata->ref_div_factor)
 167                 r_cnt = pdata->ref_div_factor - 1;
 168
 169         chspc = st->chspc;
 170
 171         do  {
 172                 do {
 173                         do {
 174                                 r_cnt = adf4350_tune_r_cnt(st, r_cnt);
 175                                 st->r1_mod = st->fpfd / chspc;
 176                                 if (r_cnt > ADF4350_MAX_R_CNT) {
 177                                         /* try higher spacing values */
 178                                         chspc++;
 179                                         r_cnt = 0;
 180                                 }
 181                         } while ((st->r1_mod > ADF4350_MAX_MODULUS) && r_cnt);
 182                 } while (r_cnt == 0);
 183
 184                 tmp = freq * (u64)st->r1_mod + (st->fpfd >> 1);
 185                 do_div(tmp, st->fpfd); /* Div round closest (n + d/2)/d */
 186                 st->r0_fract = do_div(tmp, st->r1_mod);
 187                 st->r0_int = tmp;
 188         } while (mdiv > st->r0_int);
 189
 190         band_sel_div = DIV_ROUND_UP(st->fpfd, ADF4350_MAX_BANDSEL_CLK);
 191
 192         if (st->r0_fract && st->r1_mod) {
 193                 div_gcd = gcd(st->r1_mod, st->r0_fract);
 194                 st->r1_mod /= div_gcd;
 195                 st->r0_fract /= div_gcd;
 196         } else {
 197                 st->r0_fract = 0;
 198                 st->r1_mod = 1;
 199         }
 200
 201         dev_dbg(&st->spi->dev, "VCO: %llu Hz, PFD %lu Hz\n"
 202                 "REF_DIV %d, R0_INT %d, R0_FRACT %d\n"
 203                 "R1_MOD %d, RF_DIV %d\nPRESCALER %s, BAND_SEL_DIV %d\n",
 204                 freq, st->fpfd, r_cnt, st->r0_int, st->r0_fract, st->r1_mod,
 205                 1 << st->r4_rf_div_sel, prescaler ? "8/9" : "4/5",
 206                 band_sel_div);
 207
 208         st->regs[ADF4350_REG0] = ADF4350_REG0_INT(st->r0_int) |
 209                                  ADF4350_REG0_FRACT(st->r0_fract);
 210
 211         st->regs[ADF4350_REG1] = ADF4350_REG1_PHASE(1) |
 212                                  ADF4350_REG1_MOD(st->r1_mod) |
 213                                  prescaler;
 214
 215         st->regs[ADF4350_REG2] =
 216                 ADF4350_REG2_10BIT_R_CNT(r_cnt) |
 217                 ADF4350_REG2_DOUBLE_BUFF_EN |
 218                 (pdata->ref_doubler_en ? ADF4350_REG2_RMULT2_EN : 0) |
 219                 (pdata->ref_div2_en ? ADF4350_REG2_RDIV2_EN : 0) |
 220                 (pdata->r2_user_settings & (ADF4350_REG2_PD_POLARITY_POS |
 221                 ADF4350_REG2_LDP_6ns | ADF4350_REG2_LDF_INT_N |
 222                 ADF4350_REG2_CHARGE_PUMP_CURR_uA(5000) |
 223                 ADF4350_REG2_MUXOUT(0x7) | ADF4350_REG2_NOISE_MODE(0x3)));
 224
 225         st->regs[ADF4350_REG3] = pdata->r3_user_settings &
 226                                  (ADF4350_REG3_12BIT_CLKDIV(0xFFF) |
 227                                  ADF4350_REG3_12BIT_CLKDIV_MODE(0x3) |
 228                                  ADF4350_REG3_12BIT_CSR_EN |
 229                                  ADF4351_REG3_CHARGE_CANCELLATION_EN |
 230                                  ADF4351_REG3_ANTI_BACKLASH_3ns_EN |
 231                                  ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH);
 232
 233         st->regs[ADF4350_REG4] =
 234                 ADF4350_REG4_FEEDBACK_FUND |
 235                 ADF4350_REG4_RF_DIV_SEL(st->r4_rf_div_sel) |
 236                 ADF4350_REG4_8BIT_BAND_SEL_CLKDIV(band_sel_div) |
 237                 ADF4350_REG4_RF_OUT_EN |
 238                 (pdata->r4_user_settings &
 239                 (ADF4350_REG4_OUTPUT_PWR(0x3) |
 240                 ADF4350_REG4_AUX_OUTPUT_PWR(0x3) |
 241                 ADF4350_REG4_AUX_OUTPUT_EN |
 242                 ADF4350_REG4_AUX_OUTPUT_FUND |
 243                 ADF4350_REG4_MUTE_TILL_LOCK_EN));
 244
 245         st->regs[ADF4350_REG5] = ADF4350_REG5_LD_PIN_MODE_DIGITAL;
 246         st->freq_req = freq;
 247
 248         return adf4350_sync_config(st);
 249 }
 250
 251 static ssize_t adf4350_write(struct iio_dev *indio_dev,
 252                                     uintptr_t private,
 253                                     const struct iio_chan_spec *chan,
 254                                     const char *buf, size_t len)
 255 {
 256         struct adf4350_state *st = iio_priv(indio_dev);
 257         unsigned long long readin;
 258         unsigned long tmp;
 259         int ret;
 260
 261         ret = kstrtoull(buf, 10, &readin);
 262         if (ret)
 263                 return ret;
 264
 265         mutex_lock(&st->lock);
 266         switch ((u32)private) {
 267         case ADF4350_FREQ:
 268                 ret = adf4350_set_freq(st, readin);
 269                 break;
 270         case ADF4350_FREQ_REFIN:
 271                 if (readin > ADF4350_MAX_FREQ_REFIN) {
 272                         ret = -EINVAL;
 273                         break;
 274                 }
 275
 276                 if (st->clk) {
 277                         tmp = clk_round_rate(st->clk, readin);
 278                         if (tmp != readin) {
 279                                 ret = -EINVAL;
 280                                 break;
 281                         }
 282                         ret = clk_set_rate(st->clk, tmp);
 283                         if (ret < 0)
 284                                 break;
 285                 }
 286                 st->clkin = readin;
 287                 ret = adf4350_set_freq(st, st->freq_req);
 288                 break;
 289         case ADF4350_FREQ_RESOLUTION:
 290                 if (readin == 0)
 291                         ret = -EINVAL;
 292                 else
 293                         st->chspc = readin;
 294                 break;
 295         case ADF4350_PWRDOWN:
 296                 if (readin)
 297                         st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
 298                 else
 299                         st->regs[ADF4350_REG2] &= ~ADF4350_REG2_POWER_DOWN_EN;
 300
 301                 adf4350_sync_config(st);
 302                 break;
 303         default:
 304                 ret = -EINVAL;
 305         }
 306         mutex_unlock(&st->lock);
 307
 308         return ret ? ret : len;
 309 }
 310
 311 static ssize_t adf4350_read(struct iio_dev *indio_dev,
 312                                    uintptr_t private,
 313                                    const struct iio_chan_spec *chan,
 314                                    char *buf)
 315 {
 316         struct adf4350_state *st = iio_priv(indio_dev);
 317         unsigned long long val;
 318         int ret = 0;
 319
 320         mutex_lock(&st->lock);
 321         switch ((u32)private) {
 322         case ADF4350_FREQ:
 323                 val = (u64)((st->r0_int * st->r1_mod) + st->r0_fract) *
 324                         (u64)st->fpfd;
 325                 do_div(val, st->r1_mod * (1 << st->r4_rf_div_sel));
 326                 /* PLL unlocked? return error */
 327                 if (st->lock_detect_gpiod)
 328                         if (!gpiod_get_value(st->lock_detect_gpiod)) {
 329                                 dev_dbg(&st->spi->dev, "PLL un-locked\n");
 330                                 ret = -EBUSY;
 331                         }
 332                 break;
 333         case ADF4350_FREQ_REFIN:
 334                 if (st->clk)
 335                         st->clkin = clk_get_rate(st->clk);
 336
 337                 val = st->clkin;
 338                 break;
 339         case ADF4350_FREQ_RESOLUTION:
 340                 val = st->chspc;
 341                 break;
 342         case ADF4350_PWRDOWN:
 343                 val = !!(st->regs[ADF4350_REG2] & ADF4350_REG2_POWER_DOWN_EN);
 344                 break;
 345         default:
 346                 ret = -EINVAL;
 347                 val = 0;
 348         }
 349         mutex_unlock(&st->lock);
 350
 351         return ret < 0 ? ret : sprintf(buf, "%llu\n", val);
 352 }
 353
 354 #define _ADF4350_EXT_INFO(_name, _ident) { \
 355         .name = _name, \
 356         .read = adf4350_read, \
 357         .write = adf4350_write, \
 358         .private = _ident, \
 359         .shared = IIO_SEPARATE, \
 360 }
 361
 362 static const struct iio_chan_spec_ext_info adf4350_ext_info[] = {
 363         /* Ideally we use IIO_CHAN_INFO_FREQUENCY, but there are
 364          * values > 2^32 in order to support the entire frequency range
 365          * in Hz. Using scale is a bit ugly.
 366          */
 367         _ADF4350_EXT_INFO("frequency", ADF4350_FREQ),
 368         _ADF4350_EXT_INFO("frequency_resolution", ADF4350_FREQ_RESOLUTION),
 369         _ADF4350_EXT_INFO("refin_frequency", ADF4350_FREQ_REFIN),
 370         _ADF4350_EXT_INFO("powerdown", ADF4350_PWRDOWN),
 371         { },
 372 };
 373
 374 static const struct iio_chan_spec adf4350_chan = {
 375         .type = IIO_ALTVOLTAGE,
 376         .indexed = 1,
 377         .output = 1,
 378         .ext_info = adf4350_ext_info,
 379 };
 380
 381 static const struct iio_info adf4350_info = {
 382         .debugfs_reg_access = &adf4350_reg_access,
 383 };
 384
 385 static struct adf4350_platform_data *adf4350_parse_dt(struct device *dev)
 386 {
 387         struct adf4350_platform_data *pdata;
 388         unsigned int tmp;
 389
 390         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 391         if (!pdata)
 392                 return NULL;
 393
 394         snprintf(pdata->name, sizeof(pdata->name), "%pfw", dev_fwnode(dev));
 395
 396         tmp = 10000;
 397         device_property_read_u32(dev, "adi,channel-spacing", &tmp);
 398         pdata->channel_spacing = tmp;
 399
 400         tmp = 0;
 401         device_property_read_u32(dev, "adi,power-up-frequency", &tmp);
 402         pdata->power_up_frequency = tmp;
 403
 404         tmp = 0;
 405         device_property_read_u32(dev, "adi,reference-div-factor", &tmp);
 406         pdata->ref_div_factor = tmp;
 407
 408         pdata->ref_doubler_en = device_property_read_bool(dev, "adi,reference-doubler-enable");
 409         pdata->ref_div2_en = device_property_read_bool(dev, "adi,reference-div2-enable");
 410
 411         /* r2_user_settings */
 412         pdata->r2_user_settings = 0;
 413         if (device_property_read_bool(dev, "adi,phase-detector-polarity-positive-enable"))
 414                 pdata->r2_user_settings |= ADF4350_REG2_PD_POLARITY_POS;
 415         if (device_property_read_bool(dev, "adi,lock-detect-precision-6ns-enable"))
 416                 pdata->r2_user_settings |= ADF4350_REG2_LDP_6ns;
 417         if (device_property_read_bool(dev, "adi,lock-detect-function-integer-n-enable"))
 418                 pdata->r2_user_settings |= ADF4350_REG2_LDF_INT_N;
 419
 420         tmp = 2500;
 421         device_property_read_u32(dev, "adi,charge-pump-current", &tmp);
 422         pdata->r2_user_settings |= ADF4350_REG2_CHARGE_PUMP_CURR_uA(tmp);
 423
 424         tmp = 0;
 425         device_property_read_u32(dev, "adi,muxout-select", &tmp);
 426         pdata->r2_user_settings |= ADF4350_REG2_MUXOUT(tmp);
 427
 428         if (device_property_read_bool(dev, "adi,low-spur-mode-enable"))
 429                 pdata->r2_user_settings |= ADF4350_REG2_NOISE_MODE(0x3);
 430
 431         /* r3_user_settings */
 432
 433         pdata->r3_user_settings = 0;
 434         if (device_property_read_bool(dev, "adi,cycle-slip-reduction-enable"))
 435                 pdata->r3_user_settings |= ADF4350_REG3_12BIT_CSR_EN;
 436         if (device_property_read_bool(dev, "adi,charge-cancellation-enable"))
 437                 pdata->r3_user_settings |= ADF4351_REG3_CHARGE_CANCELLATION_EN;
 438         if (device_property_read_bool(dev, "adi,anti-backlash-3ns-enable"))
 439                 pdata->r3_user_settings |= ADF4351_REG3_ANTI_BACKLASH_3ns_EN;
 440         if (device_property_read_bool(dev, "adi,band-select-clock-mode-high-enable"))
 441                 pdata->r3_user_settings |= ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH;
 442
 443         tmp = 0;
 444         device_property_read_u32(dev, "adi,12bit-clk-divider", &tmp);
 445         pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV(tmp);
 446
 447         tmp = 0;
 448         device_property_read_u32(dev, "adi,clk-divider-mode", &tmp);
 449         pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV_MODE(tmp);
 450
 451         /* r4_user_settings */
 452
 453         pdata->r4_user_settings = 0;
 454         if (device_property_read_bool(dev, "adi,aux-output-enable"))
 455                 pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_EN;
 456         if (device_property_read_bool(dev, "adi,aux-output-fundamental-enable"))
 457                 pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_FUND;
 458         if (device_property_read_bool(dev, "adi,mute-till-lock-enable"))
 459                 pdata->r4_user_settings |= ADF4350_REG4_MUTE_TILL_LOCK_EN;
 460
 461         tmp = 0;
 462         device_property_read_u32(dev, "adi,output-power", &tmp);
 463         pdata->r4_user_settings |= ADF4350_REG4_OUTPUT_PWR(tmp);
 464
 465         tmp = 0;
 466         device_property_read_u32(dev, "adi,aux-output-power", &tmp);
 467         pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_PWR(tmp);
 468
 469         return pdata;
 470 }
 471
 472 static int adf4350_probe(struct spi_device *spi)
 473 {
 474         struct adf4350_platform_data *pdata;
 475         struct iio_dev *indio_dev;
 476         struct adf4350_state *st;
 477         struct clk *clk = NULL;
 478         int ret;
 479
 480         if (dev_fwnode(&spi->dev)) {
 481                 pdata = adf4350_parse_dt(&spi->dev);
 482                 if (pdata == NULL)
 483                         return -EINVAL;
 484         } else {
 485                 pdata = spi->dev.platform_data;
 486         }
 487
 488         if (!pdata) {
 489                 dev_warn(&spi->dev, "no platform data? using default\n");
 490                 pdata = &default_pdata;
 491         }
 492
 493         if (!pdata->clkin) {
 494                 clk = devm_clk_get(&spi->dev, "clkin");
 495                 if (IS_ERR(clk))
 496                         return -EPROBE_DEFER;
 497
 498                 ret = clk_prepare_enable(clk);
 499                 if (ret < 0)
 500                         return ret;
 501         }
 502
 503         indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 504         if (indio_dev == NULL) {
 505                 ret =  -ENOMEM;
 506                 goto error_disable_clk;
 507         }
 508
 509         st = iio_priv(indio_dev);
 510
 511         st->reg = devm_regulator_get(&spi->dev, "vcc");
 512         if (!IS_ERR(st->reg)) {
 513                 ret = regulator_enable(st->reg);
 514                 if (ret)
 515                         goto error_disable_clk;
 516         }
 517
 518         spi_set_drvdata(spi, indio_dev);
 519         st->spi = spi;
 520         st->pdata = pdata;
 521
 522         indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
 523                 spi_get_device_id(spi)->name;
 524
 525         indio_dev->info = &adf4350_info;
 526         indio_dev->modes = INDIO_DIRECT_MODE;
 527         indio_dev->channels = &adf4350_chan;
 528         indio_dev->num_channels = 1;
 529
 530         mutex_init(&st->lock);
 531
 532         st->chspc = pdata->channel_spacing;
 533         if (clk) {
 534                 st->clk = clk;
 535                 st->clkin = clk_get_rate(clk);
 536         } else {
 537                 st->clkin = pdata->clkin;
 538         }
 539
 540         st->min_out_freq = spi_get_device_id(spi)->driver_data == 4351 ?
 541                 ADF4351_MIN_OUT_FREQ : ADF4350_MIN_OUT_FREQ;
 542
 543         memset(st->regs_hw, 0xFF, sizeof(st->regs_hw));
 544
 545         st->lock_detect_gpiod = devm_gpiod_get_optional(&spi->dev, NULL,
 546                                                         GPIOD_IN);
 547         if (IS_ERR(st->lock_detect_gpiod)) {
 548                 ret = PTR_ERR(st->lock_detect_gpiod);
 549                 goto error_disable_reg;
 550         }
 551
 552         if (pdata->power_up_frequency) {
 553                 ret = adf4350_set_freq(st, pdata->power_up_frequency);
 554                 if (ret)
 555                         goto error_disable_reg;
 556         }
 557
 558         ret = iio_device_register(indio_dev);
 559         if (ret)
 560                 goto error_disable_reg;
 561
 562         return 0;
 563
 564 error_disable_reg:
 565         if (!IS_ERR(st->reg))
 566                 regulator_disable(st->reg);
 567 error_disable_clk:
 568         clk_disable_unprepare(clk);
 569
 570         return ret;
 571 }
 572
 573 static void adf4350_remove(struct spi_device *spi)
 574 {
 575         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 576         struct adf4350_state *st = iio_priv(indio_dev);
 577         struct regulator *reg = st->reg;
 578
 579         st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
 580         adf4350_sync_config(st);
 581
 582         iio_device_unregister(indio_dev);
 583
 584         clk_disable_unprepare(st->clk);
 585
 586         if (!IS_ERR(reg))
 587                 regulator_disable(reg);
 588 }
 589
 590 static const struct of_device_id adf4350_of_match[] = {
 591         { .compatible = "adi,adf4350", },
 592         { .compatible = "adi,adf4351", },
 593         { /* sentinel */ },
 594 };
 595 MODULE_DEVICE_TABLE(of, adf4350_of_match);
 596
 597 static const struct spi_device_id adf4350_id[] = {
 598         {"adf4350", 4350},
 599         {"adf4351", 4351},
 600         {}
 601 };
 602 MODULE_DEVICE_TABLE(spi, adf4350_id);
 603
 604 static struct spi_driver adf4350_driver = {
 605         .driver = {
 606                 .name   = "adf4350",
 607                 .of_match_table = adf4350_of_match,
 608         },
 609         .probe          = adf4350_probe,
 610         .remove         = adf4350_remove,
 611         .id_table       = adf4350_id,
 612 };
 613 module_spi_driver(adf4350_driver);
 614
 615 MODULE_AUTHOR("Michael Hennerich <[email protected]>");
 616 MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL");
 617 MODULE_LICENSE("GPL v2");