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
27enum {
28	ADF4350_FREQ,
29	ADF4350_FREQ_REFIN,
30	ADF4350_FREQ_RESOLUTION,
31	ADF4350_PWRDOWN,
32};
33
34struct 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
64static 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
73static 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
99static 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
122static 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
135static 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
250static 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
310static 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
361static 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
373static 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
380static const struct iio_info adf4350_info = {
381	.debugfs_reg_access = &adf4350_reg_access,
382};
383
384static 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
471static 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
480static 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
562static const struct of_device_id adf4350_of_match[] = {
563	{ .compatible = "adi,adf4350", },
564	{ .compatible = "adi,adf4351", },
565	{ /* sentinel */ },
566};
567MODULE_DEVICE_TABLE(of, adf4350_of_match);
568
569static const struct spi_device_id adf4350_id[] = {
570	{"adf4350", 4350},
571	{"adf4351", 4351},
572	{}
573};
574MODULE_DEVICE_TABLE(spi, adf4350_id);
575
576static 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};
584module_spi_driver(adf4350_driver);
585
586MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
587MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL");
588MODULE_LICENSE("GPL v2");
589