xref: /openbmc/linux/drivers/iio/frequency/adf4350.c (revision 54d8c1d3)
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 gpio_desc		*lock_detect_gpiod;
37 	struct adf4350_platform_data	*pdata;
38 	struct clk			*clk;
39 	unsigned long			clkin;
40 	unsigned long			chspc; /* Channel Spacing */
41 	unsigned long			fpfd; /* Phase Frequency Detector */
42 	unsigned long			min_out_freq;
43 	unsigned			r0_fract;
44 	unsigned			r0_int;
45 	unsigned			r1_mod;
46 	unsigned			r4_rf_div_sel;
47 	unsigned long			regs[6];
48 	unsigned long			regs_hw[6];
49 	unsigned long long		freq_req;
50 	/*
51 	 * Lock to protect the state of the device from potential concurrent
52 	 * writes. The device is configured via a sequence of SPI writes,
53 	 * and this lock is meant to prevent the start of another sequence
54 	 * before another one has finished.
55 	 */
56 	struct mutex			lock;
57 	/*
58 	 * DMA (thus cache coherency maintenance) may require that
59 	 * transfer buffers live in their own cache lines.
60 	 */
61 	__be32				val __aligned(IIO_DMA_MINALIGN);
62 };
63 
64 static struct adf4350_platform_data default_pdata = {
65 	.channel_spacing = 10000,
66 	.r2_user_settings = ADF4350_REG2_PD_POLARITY_POS |
67 			    ADF4350_REG2_CHARGE_PUMP_CURR_uA(2500),
68 	.r3_user_settings = ADF4350_REG3_12BIT_CLKDIV_MODE(0),
69 	.r4_user_settings = ADF4350_REG4_OUTPUT_PWR(3) |
70 			    ADF4350_REG4_MUTE_TILL_LOCK_EN,
71 };
72 
73 static int adf4350_sync_config(struct adf4350_state *st)
74 {
75 	int ret, i, doublebuf = 0;
76 
77 	for (i = ADF4350_REG5; i >= ADF4350_REG0; i--) {
78 		if ((st->regs_hw[i] != st->regs[i]) ||
79 			((i == ADF4350_REG0) && doublebuf)) {
80 			switch (i) {
81 			case ADF4350_REG1:
82 			case ADF4350_REG4:
83 				doublebuf = 1;
84 				break;
85 			}
86 
87 			st->val  = cpu_to_be32(st->regs[i] | i);
88 			ret = spi_write(st->spi, &st->val, 4);
89 			if (ret < 0)
90 				return ret;
91 			st->regs_hw[i] = st->regs[i];
92 			dev_dbg(&st->spi->dev, "[%d] 0x%X\n",
93 				i, (u32)st->regs[i] | i);
94 		}
95 	}
96 	return 0;
97 }
98 
99 static int adf4350_reg_access(struct iio_dev *indio_dev,
100 			      unsigned reg, unsigned writeval,
101 			      unsigned *readval)
102 {
103 	struct adf4350_state *st = iio_priv(indio_dev);
104 	int ret;
105 
106 	if (reg > ADF4350_REG5)
107 		return -EINVAL;
108 
109 	mutex_lock(&st->lock);
110 	if (readval == NULL) {
111 		st->regs[reg] = writeval & ~(BIT(0) | BIT(1) | BIT(2));
112 		ret = adf4350_sync_config(st);
113 	} else {
114 		*readval =  st->regs_hw[reg];
115 		ret = 0;
116 	}
117 	mutex_unlock(&st->lock);
118 
119 	return ret;
120 }
121 
122 static int adf4350_tune_r_cnt(struct adf4350_state *st, unsigned short r_cnt)
123 {
124 	struct adf4350_platform_data *pdata = st->pdata;
125 
126 	do {
127 		r_cnt++;
128 		st->fpfd = (st->clkin * (pdata->ref_doubler_en ? 2 : 1)) /
129 			   (r_cnt * (pdata->ref_div2_en ? 2 : 1));
130 	} while (st->fpfd > ADF4350_MAX_FREQ_PFD);
131 
132 	return r_cnt;
133 }
134 
135 static int adf4350_set_freq(struct adf4350_state *st, unsigned long long freq)
136 {
137 	struct adf4350_platform_data *pdata = st->pdata;
138 	u64 tmp;
139 	u32 div_gcd, prescaler, chspc;
140 	u16 mdiv, r_cnt = 0;
141 	u8 band_sel_div;
142 
143 	if (freq > ADF4350_MAX_OUT_FREQ || freq < st->min_out_freq)
144 		return -EINVAL;
145 
146 	if (freq > ADF4350_MAX_FREQ_45_PRESC) {
147 		prescaler = ADF4350_REG1_PRESCALER;
148 		mdiv = 75;
149 	} else {
150 		prescaler = 0;
151 		mdiv = 23;
152 	}
153 
154 	st->r4_rf_div_sel = 0;
155 
156 	while (freq < ADF4350_MIN_VCO_FREQ) {
157 		freq <<= 1;
158 		st->r4_rf_div_sel++;
159 	}
160 
161 	/*
162 	 * Allow a predefined reference division factor
163 	 * if not set, compute our own
164 	 */
165 	if (pdata->ref_div_factor)
166 		r_cnt = pdata->ref_div_factor - 1;
167 
168 	chspc = st->chspc;
169 
170 	do  {
171 		do {
172 			do {
173 				r_cnt = adf4350_tune_r_cnt(st, r_cnt);
174 				st->r1_mod = st->fpfd / chspc;
175 				if (r_cnt > ADF4350_MAX_R_CNT) {
176 					/* try higher spacing values */
177 					chspc++;
178 					r_cnt = 0;
179 				}
180 			} while ((st->r1_mod > ADF4350_MAX_MODULUS) && r_cnt);
181 		} while (r_cnt == 0);
182 
183 		tmp = freq * (u64)st->r1_mod + (st->fpfd >> 1);
184 		do_div(tmp, st->fpfd); /* Div round closest (n + d/2)/d */
185 		st->r0_fract = do_div(tmp, st->r1_mod);
186 		st->r0_int = tmp;
187 	} while (mdiv > st->r0_int);
188 
189 	band_sel_div = DIV_ROUND_UP(st->fpfd, ADF4350_MAX_BANDSEL_CLK);
190 
191 	if (st->r0_fract && st->r1_mod) {
192 		div_gcd = gcd(st->r1_mod, st->r0_fract);
193 		st->r1_mod /= div_gcd;
194 		st->r0_fract /= div_gcd;
195 	} else {
196 		st->r0_fract = 0;
197 		st->r1_mod = 1;
198 	}
199 
200 	dev_dbg(&st->spi->dev, "VCO: %llu Hz, PFD %lu Hz\n"
201 		"REF_DIV %d, R0_INT %d, R0_FRACT %d\n"
202 		"R1_MOD %d, RF_DIV %d\nPRESCALER %s, BAND_SEL_DIV %d\n",
203 		freq, st->fpfd, r_cnt, st->r0_int, st->r0_fract, st->r1_mod,
204 		1 << st->r4_rf_div_sel, prescaler ? "8/9" : "4/5",
205 		band_sel_div);
206 
207 	st->regs[ADF4350_REG0] = ADF4350_REG0_INT(st->r0_int) |
208 				 ADF4350_REG0_FRACT(st->r0_fract);
209 
210 	st->regs[ADF4350_REG1] = ADF4350_REG1_PHASE(1) |
211 				 ADF4350_REG1_MOD(st->r1_mod) |
212 				 prescaler;
213 
214 	st->regs[ADF4350_REG2] =
215 		ADF4350_REG2_10BIT_R_CNT(r_cnt) |
216 		ADF4350_REG2_DOUBLE_BUFF_EN |
217 		(pdata->ref_doubler_en ? ADF4350_REG2_RMULT2_EN : 0) |
218 		(pdata->ref_div2_en ? ADF4350_REG2_RDIV2_EN : 0) |
219 		(pdata->r2_user_settings & (ADF4350_REG2_PD_POLARITY_POS |
220 		ADF4350_REG2_LDP_6ns | ADF4350_REG2_LDF_INT_N |
221 		ADF4350_REG2_CHARGE_PUMP_CURR_uA(5000) |
222 		ADF4350_REG2_MUXOUT(0x7) | ADF4350_REG2_NOISE_MODE(0x3)));
223 
224 	st->regs[ADF4350_REG3] = pdata->r3_user_settings &
225 				 (ADF4350_REG3_12BIT_CLKDIV(0xFFF) |
226 				 ADF4350_REG3_12BIT_CLKDIV_MODE(0x3) |
227 				 ADF4350_REG3_12BIT_CSR_EN |
228 				 ADF4351_REG3_CHARGE_CANCELLATION_EN |
229 				 ADF4351_REG3_ANTI_BACKLASH_3ns_EN |
230 				 ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH);
231 
232 	st->regs[ADF4350_REG4] =
233 		ADF4350_REG4_FEEDBACK_FUND |
234 		ADF4350_REG4_RF_DIV_SEL(st->r4_rf_div_sel) |
235 		ADF4350_REG4_8BIT_BAND_SEL_CLKDIV(band_sel_div) |
236 		ADF4350_REG4_RF_OUT_EN |
237 		(pdata->r4_user_settings &
238 		(ADF4350_REG4_OUTPUT_PWR(0x3) |
239 		ADF4350_REG4_AUX_OUTPUT_PWR(0x3) |
240 		ADF4350_REG4_AUX_OUTPUT_EN |
241 		ADF4350_REG4_AUX_OUTPUT_FUND |
242 		ADF4350_REG4_MUTE_TILL_LOCK_EN));
243 
244 	st->regs[ADF4350_REG5] = ADF4350_REG5_LD_PIN_MODE_DIGITAL;
245 	st->freq_req = freq;
246 
247 	return adf4350_sync_config(st);
248 }
249 
250 static ssize_t adf4350_write(struct iio_dev *indio_dev,
251 				    uintptr_t private,
252 				    const struct iio_chan_spec *chan,
253 				    const char *buf, size_t len)
254 {
255 	struct adf4350_state *st = iio_priv(indio_dev);
256 	unsigned long long readin;
257 	unsigned long tmp;
258 	int ret;
259 
260 	ret = kstrtoull(buf, 10, &readin);
261 	if (ret)
262 		return ret;
263 
264 	mutex_lock(&st->lock);
265 	switch ((u32)private) {
266 	case ADF4350_FREQ:
267 		ret = adf4350_set_freq(st, readin);
268 		break;
269 	case ADF4350_FREQ_REFIN:
270 		if (readin > ADF4350_MAX_FREQ_REFIN) {
271 			ret = -EINVAL;
272 			break;
273 		}
274 
275 		if (st->clk) {
276 			tmp = clk_round_rate(st->clk, readin);
277 			if (tmp != readin) {
278 				ret = -EINVAL;
279 				break;
280 			}
281 			ret = clk_set_rate(st->clk, tmp);
282 			if (ret < 0)
283 				break;
284 		}
285 		st->clkin = readin;
286 		ret = adf4350_set_freq(st, st->freq_req);
287 		break;
288 	case ADF4350_FREQ_RESOLUTION:
289 		if (readin == 0)
290 			ret = -EINVAL;
291 		else
292 			st->chspc = readin;
293 		break;
294 	case ADF4350_PWRDOWN:
295 		if (readin)
296 			st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
297 		else
298 			st->regs[ADF4350_REG2] &= ~ADF4350_REG2_POWER_DOWN_EN;
299 
300 		adf4350_sync_config(st);
301 		break;
302 	default:
303 		ret = -EINVAL;
304 	}
305 	mutex_unlock(&st->lock);
306 
307 	return ret ? ret : len;
308 }
309 
310 static ssize_t adf4350_read(struct iio_dev *indio_dev,
311 				   uintptr_t private,
312 				   const struct iio_chan_spec *chan,
313 				   char *buf)
314 {
315 	struct adf4350_state *st = iio_priv(indio_dev);
316 	unsigned long long val;
317 	int ret = 0;
318 
319 	mutex_lock(&st->lock);
320 	switch ((u32)private) {
321 	case ADF4350_FREQ:
322 		val = (u64)((st->r0_int * st->r1_mod) + st->r0_fract) *
323 			(u64)st->fpfd;
324 		do_div(val, st->r1_mod * (1 << st->r4_rf_div_sel));
325 		/* PLL unlocked? return error */
326 		if (st->lock_detect_gpiod)
327 			if (!gpiod_get_value(st->lock_detect_gpiod)) {
328 				dev_dbg(&st->spi->dev, "PLL un-locked\n");
329 				ret = -EBUSY;
330 			}
331 		break;
332 	case ADF4350_FREQ_REFIN:
333 		if (st->clk)
334 			st->clkin = clk_get_rate(st->clk);
335 
336 		val = st->clkin;
337 		break;
338 	case ADF4350_FREQ_RESOLUTION:
339 		val = st->chspc;
340 		break;
341 	case ADF4350_PWRDOWN:
342 		val = !!(st->regs[ADF4350_REG2] & ADF4350_REG2_POWER_DOWN_EN);
343 		break;
344 	default:
345 		ret = -EINVAL;
346 		val = 0;
347 	}
348 	mutex_unlock(&st->lock);
349 
350 	return ret < 0 ? ret : sprintf(buf, "%llu\n", val);
351 }
352 
353 #define _ADF4350_EXT_INFO(_name, _ident) { \
354 	.name = _name, \
355 	.read = adf4350_read, \
356 	.write = adf4350_write, \
357 	.private = _ident, \
358 	.shared = IIO_SEPARATE, \
359 }
360 
361 static const struct iio_chan_spec_ext_info adf4350_ext_info[] = {
362 	/* Ideally we use IIO_CHAN_INFO_FREQUENCY, but there are
363 	 * values > 2^32 in order to support the entire frequency range
364 	 * in Hz. Using scale is a bit ugly.
365 	 */
366 	_ADF4350_EXT_INFO("frequency", ADF4350_FREQ),
367 	_ADF4350_EXT_INFO("frequency_resolution", ADF4350_FREQ_RESOLUTION),
368 	_ADF4350_EXT_INFO("refin_frequency", ADF4350_FREQ_REFIN),
369 	_ADF4350_EXT_INFO("powerdown", ADF4350_PWRDOWN),
370 	{ },
371 };
372 
373 static const struct iio_chan_spec adf4350_chan = {
374 	.type = IIO_ALTVOLTAGE,
375 	.indexed = 1,
376 	.output = 1,
377 	.ext_info = adf4350_ext_info,
378 };
379 
380 static const struct iio_info adf4350_info = {
381 	.debugfs_reg_access = &adf4350_reg_access,
382 };
383 
384 static struct adf4350_platform_data *adf4350_parse_dt(struct device *dev)
385 {
386 	struct adf4350_platform_data *pdata;
387 	unsigned int tmp;
388 
389 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
390 	if (!pdata)
391 		return NULL;
392 
393 	snprintf(pdata->name, sizeof(pdata->name), "%pfw", dev_fwnode(dev));
394 
395 	tmp = 10000;
396 	device_property_read_u32(dev, "adi,channel-spacing", &tmp);
397 	pdata->channel_spacing = tmp;
398 
399 	tmp = 0;
400 	device_property_read_u32(dev, "adi,power-up-frequency", &tmp);
401 	pdata->power_up_frequency = tmp;
402 
403 	tmp = 0;
404 	device_property_read_u32(dev, "adi,reference-div-factor", &tmp);
405 	pdata->ref_div_factor = tmp;
406 
407 	pdata->ref_doubler_en = device_property_read_bool(dev, "adi,reference-doubler-enable");
408 	pdata->ref_div2_en = device_property_read_bool(dev, "adi,reference-div2-enable");
409 
410 	/* r2_user_settings */
411 	pdata->r2_user_settings = 0;
412 	if (device_property_read_bool(dev, "adi,phase-detector-polarity-positive-enable"))
413 		pdata->r2_user_settings |= ADF4350_REG2_PD_POLARITY_POS;
414 	if (device_property_read_bool(dev, "adi,lock-detect-precision-6ns-enable"))
415 		pdata->r2_user_settings |= ADF4350_REG2_LDP_6ns;
416 	if (device_property_read_bool(dev, "adi,lock-detect-function-integer-n-enable"))
417 		pdata->r2_user_settings |= ADF4350_REG2_LDF_INT_N;
418 
419 	tmp = 2500;
420 	device_property_read_u32(dev, "adi,charge-pump-current", &tmp);
421 	pdata->r2_user_settings |= ADF4350_REG2_CHARGE_PUMP_CURR_uA(tmp);
422 
423 	tmp = 0;
424 	device_property_read_u32(dev, "adi,muxout-select", &tmp);
425 	pdata->r2_user_settings |= ADF4350_REG2_MUXOUT(tmp);
426 
427 	if (device_property_read_bool(dev, "adi,low-spur-mode-enable"))
428 		pdata->r2_user_settings |= ADF4350_REG2_NOISE_MODE(0x3);
429 
430 	/* r3_user_settings */
431 
432 	pdata->r3_user_settings = 0;
433 	if (device_property_read_bool(dev, "adi,cycle-slip-reduction-enable"))
434 		pdata->r3_user_settings |= ADF4350_REG3_12BIT_CSR_EN;
435 	if (device_property_read_bool(dev, "adi,charge-cancellation-enable"))
436 		pdata->r3_user_settings |= ADF4351_REG3_CHARGE_CANCELLATION_EN;
437 	if (device_property_read_bool(dev, "adi,anti-backlash-3ns-enable"))
438 		pdata->r3_user_settings |= ADF4351_REG3_ANTI_BACKLASH_3ns_EN;
439 	if (device_property_read_bool(dev, "adi,band-select-clock-mode-high-enable"))
440 		pdata->r3_user_settings |= ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH;
441 
442 	tmp = 0;
443 	device_property_read_u32(dev, "adi,12bit-clk-divider", &tmp);
444 	pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV(tmp);
445 
446 	tmp = 0;
447 	device_property_read_u32(dev, "adi,clk-divider-mode", &tmp);
448 	pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV_MODE(tmp);
449 
450 	/* r4_user_settings */
451 
452 	pdata->r4_user_settings = 0;
453 	if (device_property_read_bool(dev, "adi,aux-output-enable"))
454 		pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_EN;
455 	if (device_property_read_bool(dev, "adi,aux-output-fundamental-enable"))
456 		pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_FUND;
457 	if (device_property_read_bool(dev, "adi,mute-till-lock-enable"))
458 		pdata->r4_user_settings |= ADF4350_REG4_MUTE_TILL_LOCK_EN;
459 
460 	tmp = 0;
461 	device_property_read_u32(dev, "adi,output-power", &tmp);
462 	pdata->r4_user_settings |= ADF4350_REG4_OUTPUT_PWR(tmp);
463 
464 	tmp = 0;
465 	device_property_read_u32(dev, "adi,aux-output-power", &tmp);
466 	pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_PWR(tmp);
467 
468 	return pdata;
469 }
470 
471 static void adf4350_power_down(void *data)
472 {
473 	struct iio_dev *indio_dev = data;
474 	struct adf4350_state *st = iio_priv(indio_dev);
475 
476 	st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
477 	adf4350_sync_config(st);
478 }
479 
480 static int adf4350_probe(struct spi_device *spi)
481 {
482 	struct adf4350_platform_data *pdata;
483 	struct iio_dev *indio_dev;
484 	struct adf4350_state *st;
485 	struct clk *clk = NULL;
486 	int ret;
487 
488 	if (dev_fwnode(&spi->dev)) {
489 		pdata = adf4350_parse_dt(&spi->dev);
490 		if (pdata == NULL)
491 			return -EINVAL;
492 	} else {
493 		pdata = spi->dev.platform_data;
494 	}
495 
496 	if (!pdata) {
497 		dev_warn(&spi->dev, "no platform data? using default\n");
498 		pdata = &default_pdata;
499 	}
500 
501 	if (!pdata->clkin) {
502 		clk = devm_clk_get_enabled(&spi->dev, "clkin");
503 		if (IS_ERR(clk))
504 			return PTR_ERR(clk);
505 	}
506 
507 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
508 	if (indio_dev == NULL)
509 		return -ENOMEM;
510 
511 	st = iio_priv(indio_dev);
512 
513 	ret = devm_regulator_get_enable(&spi->dev, "vcc");
514 	if (ret)
515 		return ret;
516 
517 	st->spi = spi;
518 	st->pdata = pdata;
519 
520 	indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
521 		spi_get_device_id(spi)->name;
522 
523 	indio_dev->info = &adf4350_info;
524 	indio_dev->modes = INDIO_DIRECT_MODE;
525 	indio_dev->channels = &adf4350_chan;
526 	indio_dev->num_channels = 1;
527 
528 	mutex_init(&st->lock);
529 
530 	st->chspc = pdata->channel_spacing;
531 	if (clk) {
532 		st->clk = clk;
533 		st->clkin = clk_get_rate(clk);
534 	} else {
535 		st->clkin = pdata->clkin;
536 	}
537 
538 	st->min_out_freq = spi_get_device_id(spi)->driver_data == 4351 ?
539 		ADF4351_MIN_OUT_FREQ : ADF4350_MIN_OUT_FREQ;
540 
541 	memset(st->regs_hw, 0xFF, sizeof(st->regs_hw));
542 
543 	st->lock_detect_gpiod = devm_gpiod_get_optional(&spi->dev, NULL,
544 							GPIOD_IN);
545 	if (IS_ERR(st->lock_detect_gpiod))
546 		return PTR_ERR(st->lock_detect_gpiod);
547 
548 	if (pdata->power_up_frequency) {
549 		ret = adf4350_set_freq(st, pdata->power_up_frequency);
550 		if (ret)
551 			return ret;
552 	}
553 
554 	ret = devm_add_action_or_reset(&spi->dev, adf4350_power_down, indio_dev);
555 	if (ret)
556 		return dev_err_probe(&spi->dev, ret,
557 				     "Failed to add action to managed power down\n");
558 
559 	return devm_iio_device_register(&spi->dev, indio_dev);
560 }
561 
562 static const struct of_device_id adf4350_of_match[] = {
563 	{ .compatible = "adi,adf4350", },
564 	{ .compatible = "adi,adf4351", },
565 	{ /* sentinel */ },
566 };
567 MODULE_DEVICE_TABLE(of, adf4350_of_match);
568 
569 static const struct spi_device_id adf4350_id[] = {
570 	{"adf4350", 4350},
571 	{"adf4351", 4351},
572 	{}
573 };
574 MODULE_DEVICE_TABLE(spi, adf4350_id);
575 
576 static struct spi_driver adf4350_driver = {
577 	.driver = {
578 		.name	= "adf4350",
579 		.of_match_table = adf4350_of_match,
580 	},
581 	.probe		= adf4350_probe,
582 	.id_table	= adf4350_id,
583 };
584 module_spi_driver(adf4350_driver);
585 
586 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
587 MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL");
588 MODULE_LICENSE("GPL v2");
589