1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Analog Devices ADF4371 SPI Wideband Synthesizer driver 4 * 5 * Copyright 2019 Analog Devices Inc. 6 */ 7 #include <linux/bitfield.h> 8 #include <linux/clk.h> 9 #include <linux/device.h> 10 #include <linux/err.h> 11 #include <linux/gcd.h> 12 #include <linux/kernel.h> 13 #include <linux/module.h> 14 #include <linux/regmap.h> 15 #include <linux/sysfs.h> 16 #include <linux/spi/spi.h> 17 18 #include <linux/iio/iio.h> 19 20 /* Registers address macro */ 21 #define ADF4371_REG(x) (x) 22 23 /* ADF4371_REG0 */ 24 #define ADF4371_ADDR_ASC_MSK BIT(2) 25 #define ADF4371_ADDR_ASC(x) FIELD_PREP(ADF4371_ADDR_ASC_MSK, x) 26 #define ADF4371_ADDR_ASC_R_MSK BIT(5) 27 #define ADF4371_ADDR_ASC_R(x) FIELD_PREP(ADF4371_ADDR_ASC_R_MSK, x) 28 #define ADF4371_RESET_CMD 0x81 29 30 /* ADF4371_REG17 */ 31 #define ADF4371_FRAC2WORD_L_MSK GENMASK(7, 1) 32 #define ADF4371_FRAC2WORD_L(x) FIELD_PREP(ADF4371_FRAC2WORD_L_MSK, x) 33 #define ADF4371_FRAC1WORD_MSK BIT(0) 34 #define ADF4371_FRAC1WORD(x) FIELD_PREP(ADF4371_FRAC1WORD_MSK, x) 35 36 /* ADF4371_REG18 */ 37 #define ADF4371_FRAC2WORD_H_MSK GENMASK(6, 0) 38 #define ADF4371_FRAC2WORD_H(x) FIELD_PREP(ADF4371_FRAC2WORD_H_MSK, x) 39 40 /* ADF4371_REG1A */ 41 #define ADF4371_MOD2WORD_MSK GENMASK(5, 0) 42 #define ADF4371_MOD2WORD(x) FIELD_PREP(ADF4371_MOD2WORD_MSK, x) 43 44 /* ADF4371_REG24 */ 45 #define ADF4371_RF_DIV_SEL_MSK GENMASK(6, 4) 46 #define ADF4371_RF_DIV_SEL(x) FIELD_PREP(ADF4371_RF_DIV_SEL_MSK, x) 47 48 /* ADF4371_REG25 */ 49 #define ADF4371_MUTE_LD_MSK BIT(7) 50 #define ADF4371_MUTE_LD(x) FIELD_PREP(ADF4371_MUTE_LD_MSK, x) 51 52 /* ADF4371_REG32 */ 53 #define ADF4371_TIMEOUT_MSK GENMASK(1, 0) 54 #define ADF4371_TIMEOUT(x) FIELD_PREP(ADF4371_TIMEOUT_MSK, x) 55 56 /* ADF4371_REG34 */ 57 #define ADF4371_VCO_ALC_TOUT_MSK GENMASK(4, 0) 58 #define ADF4371_VCO_ALC_TOUT(x) FIELD_PREP(ADF4371_VCO_ALC_TOUT_MSK, x) 59 60 /* Specifications */ 61 #define ADF4371_MIN_VCO_FREQ 4000000000ULL /* 4000 MHz */ 62 #define ADF4371_MAX_VCO_FREQ 8000000000ULL /* 8000 MHz */ 63 #define ADF4371_MAX_OUT_RF8_FREQ ADF4371_MAX_VCO_FREQ /* Hz */ 64 #define ADF4371_MIN_OUT_RF8_FREQ (ADF4371_MIN_VCO_FREQ / 64) /* Hz */ 65 #define ADF4371_MAX_OUT_RF16_FREQ (ADF4371_MAX_VCO_FREQ * 2) /* Hz */ 66 #define ADF4371_MIN_OUT_RF16_FREQ (ADF4371_MIN_VCO_FREQ * 2) /* Hz */ 67 #define ADF4371_MAX_OUT_RF32_FREQ (ADF4371_MAX_VCO_FREQ * 4) /* Hz */ 68 #define ADF4371_MIN_OUT_RF32_FREQ (ADF4371_MIN_VCO_FREQ * 4) /* Hz */ 69 70 #define ADF4371_MAX_FREQ_PFD 250000000UL /* Hz */ 71 #define ADF4371_MAX_FREQ_REFIN 600000000UL /* Hz */ 72 73 /* MOD1 is a 24-bit primary modulus with fixed value of 2^25 */ 74 #define ADF4371_MODULUS1 33554432ULL 75 /* MOD2 is the programmable, 14-bit auxiliary fractional modulus */ 76 #define ADF4371_MAX_MODULUS2 BIT(14) 77 78 #define ADF4371_CHECK_RANGE(freq, range) \ 79 ((freq > ADF4371_MAX_ ## range) || (freq < ADF4371_MIN_ ## range)) 80 81 enum { 82 ADF4371_FREQ, 83 ADF4371_POWER_DOWN, 84 ADF4371_CHANNEL_NAME 85 }; 86 87 enum { 88 ADF4371_CH_RF8, 89 ADF4371_CH_RFAUX8, 90 ADF4371_CH_RF16, 91 ADF4371_CH_RF32 92 }; 93 94 enum adf4371_variant { 95 ADF4371, 96 ADF4372 97 }; 98 99 struct adf4371_pwrdown { 100 unsigned int reg; 101 unsigned int bit; 102 }; 103 104 static const char * const adf4371_ch_names[] = { 105 "RF8x", "RFAUX8x", "RF16x", "RF32x" 106 }; 107 108 static const struct adf4371_pwrdown adf4371_pwrdown_ch[4] = { 109 [ADF4371_CH_RF8] = { ADF4371_REG(0x25), 2 }, 110 [ADF4371_CH_RFAUX8] = { ADF4371_REG(0x72), 3 }, 111 [ADF4371_CH_RF16] = { ADF4371_REG(0x25), 3 }, 112 [ADF4371_CH_RF32] = { ADF4371_REG(0x25), 4 }, 113 }; 114 115 static const struct reg_sequence adf4371_reg_defaults[] = { 116 { ADF4371_REG(0x0), 0x18 }, 117 { ADF4371_REG(0x12), 0x40 }, 118 { ADF4371_REG(0x1E), 0x48 }, 119 { ADF4371_REG(0x20), 0x14 }, 120 { ADF4371_REG(0x22), 0x00 }, 121 { ADF4371_REG(0x23), 0x00 }, 122 { ADF4371_REG(0x24), 0x80 }, 123 { ADF4371_REG(0x25), 0x07 }, 124 { ADF4371_REG(0x27), 0xC5 }, 125 { ADF4371_REG(0x28), 0x83 }, 126 { ADF4371_REG(0x2C), 0x44 }, 127 { ADF4371_REG(0x2D), 0x11 }, 128 { ADF4371_REG(0x2E), 0x12 }, 129 { ADF4371_REG(0x2F), 0x94 }, 130 { ADF4371_REG(0x32), 0x04 }, 131 { ADF4371_REG(0x35), 0xFA }, 132 { ADF4371_REG(0x36), 0x30 }, 133 { ADF4371_REG(0x39), 0x07 }, 134 { ADF4371_REG(0x3A), 0x55 }, 135 { ADF4371_REG(0x3E), 0x0C }, 136 { ADF4371_REG(0x3F), 0x80 }, 137 { ADF4371_REG(0x40), 0x50 }, 138 { ADF4371_REG(0x41), 0x28 }, 139 { ADF4371_REG(0x47), 0xC0 }, 140 { ADF4371_REG(0x52), 0xF4 }, 141 { ADF4371_REG(0x70), 0x03 }, 142 { ADF4371_REG(0x71), 0x60 }, 143 { ADF4371_REG(0x72), 0x32 }, 144 }; 145 146 static const struct regmap_config adf4371_regmap_config = { 147 .reg_bits = 16, 148 .val_bits = 8, 149 .read_flag_mask = BIT(7), 150 }; 151 152 struct adf4371_chip_info { 153 unsigned int num_channels; 154 const struct iio_chan_spec *channels; 155 }; 156 157 struct adf4371_state { 158 struct spi_device *spi; 159 struct regmap *regmap; 160 struct clk *clkin; 161 /* 162 * Lock for accessing device registers. Some operations require 163 * multiple consecutive R/W operations, during which the device 164 * shouldn't be interrupted. The buffers are also shared across 165 * all operations so need to be protected on stand alone reads and 166 * writes. 167 */ 168 struct mutex lock; 169 const struct adf4371_chip_info *chip_info; 170 unsigned long clkin_freq; 171 unsigned long fpfd; 172 unsigned int integer; 173 unsigned int fract1; 174 unsigned int fract2; 175 unsigned int mod2; 176 unsigned int rf_div_sel; 177 unsigned int ref_div_factor; 178 u8 buf[10] __aligned(IIO_DMA_MINALIGN); 179 }; 180 181 static unsigned long long adf4371_pll_fract_n_get_rate(struct adf4371_state *st, 182 u32 channel) 183 { 184 unsigned long long val, tmp; 185 unsigned int ref_div_sel; 186 187 val = (((u64)st->integer * ADF4371_MODULUS1) + st->fract1) * st->fpfd; 188 tmp = (u64)st->fract2 * st->fpfd; 189 do_div(tmp, st->mod2); 190 val += tmp + ADF4371_MODULUS1 / 2; 191 192 if (channel == ADF4371_CH_RF8 || channel == ADF4371_CH_RFAUX8) 193 ref_div_sel = st->rf_div_sel; 194 else 195 ref_div_sel = 0; 196 197 do_div(val, ADF4371_MODULUS1 * (1 << ref_div_sel)); 198 199 if (channel == ADF4371_CH_RF16) 200 val <<= 1; 201 else if (channel == ADF4371_CH_RF32) 202 val <<= 2; 203 204 return val; 205 } 206 207 static void adf4371_pll_fract_n_compute(unsigned long long vco, 208 unsigned long long pfd, 209 unsigned int *integer, 210 unsigned int *fract1, 211 unsigned int *fract2, 212 unsigned int *mod2) 213 { 214 unsigned long long tmp; 215 u32 gcd_div; 216 217 tmp = do_div(vco, pfd); 218 tmp = tmp * ADF4371_MODULUS1; 219 *fract2 = do_div(tmp, pfd); 220 221 *integer = vco; 222 *fract1 = tmp; 223 224 *mod2 = pfd; 225 226 while (*mod2 > ADF4371_MAX_MODULUS2) { 227 *mod2 >>= 1; 228 *fract2 >>= 1; 229 } 230 231 gcd_div = gcd(*fract2, *mod2); 232 *mod2 /= gcd_div; 233 *fract2 /= gcd_div; 234 } 235 236 static int adf4371_set_freq(struct adf4371_state *st, unsigned long long freq, 237 unsigned int channel) 238 { 239 u32 cp_bleed; 240 u8 int_mode = 0; 241 int ret; 242 243 switch (channel) { 244 case ADF4371_CH_RF8: 245 case ADF4371_CH_RFAUX8: 246 if (ADF4371_CHECK_RANGE(freq, OUT_RF8_FREQ)) 247 return -EINVAL; 248 249 st->rf_div_sel = 0; 250 251 while (freq < ADF4371_MIN_VCO_FREQ) { 252 freq <<= 1; 253 st->rf_div_sel++; 254 } 255 break; 256 case ADF4371_CH_RF16: 257 /* ADF4371 RF16 8000...16000 MHz */ 258 if (ADF4371_CHECK_RANGE(freq, OUT_RF16_FREQ)) 259 return -EINVAL; 260 261 freq >>= 1; 262 break; 263 case ADF4371_CH_RF32: 264 /* ADF4371 RF32 16000...32000 MHz */ 265 if (ADF4371_CHECK_RANGE(freq, OUT_RF32_FREQ)) 266 return -EINVAL; 267 268 freq >>= 2; 269 break; 270 default: 271 return -EINVAL; 272 } 273 274 adf4371_pll_fract_n_compute(freq, st->fpfd, &st->integer, &st->fract1, 275 &st->fract2, &st->mod2); 276 st->buf[0] = st->integer >> 8; 277 st->buf[1] = 0x40; /* REG12 default */ 278 st->buf[2] = 0x00; 279 st->buf[3] = st->fract1 & 0xFF; 280 st->buf[4] = st->fract1 >> 8; 281 st->buf[5] = st->fract1 >> 16; 282 st->buf[6] = ADF4371_FRAC2WORD_L(st->fract2 & 0x7F) | 283 ADF4371_FRAC1WORD(st->fract1 >> 24); 284 st->buf[7] = ADF4371_FRAC2WORD_H(st->fract2 >> 7); 285 st->buf[8] = st->mod2 & 0xFF; 286 st->buf[9] = ADF4371_MOD2WORD(st->mod2 >> 8); 287 288 ret = regmap_bulk_write(st->regmap, ADF4371_REG(0x11), st->buf, 10); 289 if (ret < 0) 290 return ret; 291 /* 292 * The R counter allows the input reference frequency to be 293 * divided down to produce the reference clock to the PFD 294 */ 295 ret = regmap_write(st->regmap, ADF4371_REG(0x1F), st->ref_div_factor); 296 if (ret < 0) 297 return ret; 298 299 ret = regmap_update_bits(st->regmap, ADF4371_REG(0x24), 300 ADF4371_RF_DIV_SEL_MSK, 301 ADF4371_RF_DIV_SEL(st->rf_div_sel)); 302 if (ret < 0) 303 return ret; 304 305 cp_bleed = DIV_ROUND_UP(400 * 1750, st->integer * 375); 306 cp_bleed = clamp(cp_bleed, 1U, 255U); 307 ret = regmap_write(st->regmap, ADF4371_REG(0x26), cp_bleed); 308 if (ret < 0) 309 return ret; 310 /* 311 * Set to 1 when in INT mode (when FRAC1 = FRAC2 = 0), 312 * and set to 0 when in FRAC mode. 313 */ 314 if (st->fract1 == 0 && st->fract2 == 0) 315 int_mode = 0x01; 316 317 ret = regmap_write(st->regmap, ADF4371_REG(0x2B), int_mode); 318 if (ret < 0) 319 return ret; 320 321 return regmap_write(st->regmap, ADF4371_REG(0x10), st->integer & 0xFF); 322 } 323 324 static ssize_t adf4371_read(struct iio_dev *indio_dev, 325 uintptr_t private, 326 const struct iio_chan_spec *chan, 327 char *buf) 328 { 329 struct adf4371_state *st = iio_priv(indio_dev); 330 unsigned long long val = 0; 331 unsigned int readval, reg, bit; 332 int ret; 333 334 switch ((u32)private) { 335 case ADF4371_FREQ: 336 val = adf4371_pll_fract_n_get_rate(st, chan->channel); 337 ret = regmap_read(st->regmap, ADF4371_REG(0x7C), &readval); 338 if (ret < 0) 339 break; 340 341 if (readval == 0x00) { 342 dev_dbg(&st->spi->dev, "PLL un-locked\n"); 343 ret = -EBUSY; 344 } 345 break; 346 case ADF4371_POWER_DOWN: 347 reg = adf4371_pwrdown_ch[chan->channel].reg; 348 bit = adf4371_pwrdown_ch[chan->channel].bit; 349 350 ret = regmap_read(st->regmap, reg, &readval); 351 if (ret < 0) 352 break; 353 354 val = !(readval & BIT(bit)); 355 break; 356 case ADF4371_CHANNEL_NAME: 357 return sprintf(buf, "%s\n", adf4371_ch_names[chan->channel]); 358 default: 359 ret = -EINVAL; 360 val = 0; 361 break; 362 } 363 364 return ret < 0 ? ret : sprintf(buf, "%llu\n", val); 365 } 366 367 static ssize_t adf4371_write(struct iio_dev *indio_dev, 368 uintptr_t private, 369 const struct iio_chan_spec *chan, 370 const char *buf, size_t len) 371 { 372 struct adf4371_state *st = iio_priv(indio_dev); 373 unsigned long long freq; 374 bool power_down; 375 unsigned int bit, readval, reg; 376 int ret; 377 378 mutex_lock(&st->lock); 379 switch ((u32)private) { 380 case ADF4371_FREQ: 381 ret = kstrtoull(buf, 10, &freq); 382 if (ret) 383 break; 384 385 ret = adf4371_set_freq(st, freq, chan->channel); 386 break; 387 case ADF4371_POWER_DOWN: 388 ret = kstrtobool(buf, &power_down); 389 if (ret) 390 break; 391 392 reg = adf4371_pwrdown_ch[chan->channel].reg; 393 bit = adf4371_pwrdown_ch[chan->channel].bit; 394 ret = regmap_read(st->regmap, reg, &readval); 395 if (ret < 0) 396 break; 397 398 readval &= ~BIT(bit); 399 readval |= (!power_down << bit); 400 401 ret = regmap_write(st->regmap, reg, readval); 402 break; 403 default: 404 ret = -EINVAL; 405 break; 406 } 407 mutex_unlock(&st->lock); 408 409 return ret ? ret : len; 410 } 411 412 #define _ADF4371_EXT_INFO(_name, _ident) { \ 413 .name = _name, \ 414 .read = adf4371_read, \ 415 .write = adf4371_write, \ 416 .private = _ident, \ 417 .shared = IIO_SEPARATE, \ 418 } 419 420 static const struct iio_chan_spec_ext_info adf4371_ext_info[] = { 421 /* 422 * Ideally we use IIO_CHAN_INFO_FREQUENCY, but there are 423 * values > 2^32 in order to support the entire frequency range 424 * in Hz. Using scale is a bit ugly. 425 */ 426 _ADF4371_EXT_INFO("frequency", ADF4371_FREQ), 427 _ADF4371_EXT_INFO("powerdown", ADF4371_POWER_DOWN), 428 _ADF4371_EXT_INFO("name", ADF4371_CHANNEL_NAME), 429 { }, 430 }; 431 432 #define ADF4371_CHANNEL(index) { \ 433 .type = IIO_ALTVOLTAGE, \ 434 .output = 1, \ 435 .channel = index, \ 436 .ext_info = adf4371_ext_info, \ 437 .indexed = 1, \ 438 } 439 440 static const struct iio_chan_spec adf4371_chan[] = { 441 ADF4371_CHANNEL(ADF4371_CH_RF8), 442 ADF4371_CHANNEL(ADF4371_CH_RFAUX8), 443 ADF4371_CHANNEL(ADF4371_CH_RF16), 444 ADF4371_CHANNEL(ADF4371_CH_RF32), 445 }; 446 447 static const struct adf4371_chip_info adf4371_chip_info[] = { 448 [ADF4371] = { 449 .channels = adf4371_chan, 450 .num_channels = 4, 451 }, 452 [ADF4372] = { 453 .channels = adf4371_chan, 454 .num_channels = 3, 455 } 456 }; 457 458 static int adf4371_reg_access(struct iio_dev *indio_dev, 459 unsigned int reg, 460 unsigned int writeval, 461 unsigned int *readval) 462 { 463 struct adf4371_state *st = iio_priv(indio_dev); 464 465 if (readval) 466 return regmap_read(st->regmap, reg, readval); 467 else 468 return regmap_write(st->regmap, reg, writeval); 469 } 470 471 static const struct iio_info adf4371_info = { 472 .debugfs_reg_access = &adf4371_reg_access, 473 }; 474 475 static int adf4371_setup(struct adf4371_state *st) 476 { 477 unsigned int synth_timeout = 2, timeout = 1, vco_alc_timeout = 1; 478 unsigned int vco_band_div, tmp; 479 int ret; 480 481 /* Perform a software reset */ 482 ret = regmap_write(st->regmap, ADF4371_REG(0x0), ADF4371_RESET_CMD); 483 if (ret < 0) 484 return ret; 485 486 ret = regmap_multi_reg_write(st->regmap, adf4371_reg_defaults, 487 ARRAY_SIZE(adf4371_reg_defaults)); 488 if (ret < 0) 489 return ret; 490 491 /* Mute to Lock Detect */ 492 if (device_property_read_bool(&st->spi->dev, "adi,mute-till-lock-en")) { 493 ret = regmap_update_bits(st->regmap, ADF4371_REG(0x25), 494 ADF4371_MUTE_LD_MSK, 495 ADF4371_MUTE_LD(1)); 496 if (ret < 0) 497 return ret; 498 } 499 500 /* Set address in ascending order, so the bulk_write() will work */ 501 ret = regmap_update_bits(st->regmap, ADF4371_REG(0x0), 502 ADF4371_ADDR_ASC_MSK | ADF4371_ADDR_ASC_R_MSK, 503 ADF4371_ADDR_ASC(1) | ADF4371_ADDR_ASC_R(1)); 504 if (ret < 0) 505 return ret; 506 /* 507 * Calculate and maximize PFD frequency 508 * fPFD = REFIN × ((1 + D)/(R × (1 + T))) 509 * Where D is the REFIN doubler bit, T is the reference divide by 2, 510 * R is the reference division factor 511 * TODO: it is assumed D and T equal 0. 512 */ 513 do { 514 st->ref_div_factor++; 515 st->fpfd = st->clkin_freq / st->ref_div_factor; 516 } while (st->fpfd > ADF4371_MAX_FREQ_PFD); 517 518 /* Calculate Timeouts */ 519 vco_band_div = DIV_ROUND_UP(st->fpfd, 2400000U); 520 521 tmp = DIV_ROUND_CLOSEST(st->fpfd, 1000000U); 522 do { 523 timeout++; 524 if (timeout > 1023) { 525 timeout = 2; 526 synth_timeout++; 527 } 528 } while (synth_timeout * 1024 + timeout <= 20 * tmp); 529 530 do { 531 vco_alc_timeout++; 532 } while (vco_alc_timeout * 1024 - timeout <= 50 * tmp); 533 534 st->buf[0] = vco_band_div; 535 st->buf[1] = timeout & 0xFF; 536 st->buf[2] = ADF4371_TIMEOUT(timeout >> 8) | 0x04; 537 st->buf[3] = synth_timeout; 538 st->buf[4] = ADF4371_VCO_ALC_TOUT(vco_alc_timeout); 539 540 return regmap_bulk_write(st->regmap, ADF4371_REG(0x30), st->buf, 5); 541 } 542 543 static int adf4371_probe(struct spi_device *spi) 544 { 545 const struct spi_device_id *id = spi_get_device_id(spi); 546 struct iio_dev *indio_dev; 547 struct adf4371_state *st; 548 struct regmap *regmap; 549 int ret; 550 551 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); 552 if (!indio_dev) 553 return -ENOMEM; 554 555 regmap = devm_regmap_init_spi(spi, &adf4371_regmap_config); 556 if (IS_ERR(regmap)) { 557 dev_err(&spi->dev, "Error initializing spi regmap: %ld\n", 558 PTR_ERR(regmap)); 559 return PTR_ERR(regmap); 560 } 561 562 st = iio_priv(indio_dev); 563 spi_set_drvdata(spi, indio_dev); 564 st->spi = spi; 565 st->regmap = regmap; 566 mutex_init(&st->lock); 567 568 st->chip_info = &adf4371_chip_info[id->driver_data]; 569 indio_dev->name = id->name; 570 indio_dev->info = &adf4371_info; 571 indio_dev->modes = INDIO_DIRECT_MODE; 572 indio_dev->channels = st->chip_info->channels; 573 indio_dev->num_channels = st->chip_info->num_channels; 574 575 st->clkin = devm_clk_get_enabled(&spi->dev, "clkin"); 576 if (IS_ERR(st->clkin)) 577 return PTR_ERR(st->clkin); 578 579 st->clkin_freq = clk_get_rate(st->clkin); 580 581 ret = adf4371_setup(st); 582 if (ret < 0) { 583 dev_err(&spi->dev, "ADF4371 setup failed\n"); 584 return ret; 585 } 586 587 return devm_iio_device_register(&spi->dev, indio_dev); 588 } 589 590 static const struct spi_device_id adf4371_id_table[] = { 591 { "adf4371", ADF4371 }, 592 { "adf4372", ADF4372 }, 593 {} 594 }; 595 MODULE_DEVICE_TABLE(spi, adf4371_id_table); 596 597 static const struct of_device_id adf4371_of_match[] = { 598 { .compatible = "adi,adf4371" }, 599 { .compatible = "adi,adf4372" }, 600 { }, 601 }; 602 MODULE_DEVICE_TABLE(of, adf4371_of_match); 603 604 static struct spi_driver adf4371_driver = { 605 .driver = { 606 .name = "adf4371", 607 .of_match_table = adf4371_of_match, 608 }, 609 .probe = adf4371_probe, 610 .id_table = adf4371_id_table, 611 }; 612 module_spi_driver(adf4371_driver); 613 614 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>"); 615 MODULE_DESCRIPTION("Analog Devices ADF4371 SPI PLL"); 616 MODULE_LICENSE("GPL"); 617