1/*
2 * ADF4350/ADF4351 SPI Wideband Synthesizer driver
3 *
4 * Copyright 2012-2013 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2.
7 */
8
9#include <linux/device.h>
10#include <linux/kernel.h>
11#include <linux/slab.h>
12#include <linux/sysfs.h>
13#include <linux/spi/spi.h>
14#include <linux/regulator/consumer.h>
15#include <linux/err.h>
16#include <linux/module.h>
17#include <linux/gcd.h>
18#include <linux/gpio.h>
19#include <asm/div64.h>
20#include <linux/clk.h>
21#include <linux/of.h>
22#include <linux/of_gpio.h>
23
24#include <linux/iio/iio.h>
25#include <linux/iio/sysfs.h>
26#include <linux/iio/frequency/adf4350.h>
27
28enum {
29	ADF4350_FREQ,
30	ADF4350_FREQ_REFIN,
31	ADF4350_FREQ_RESOLUTION,
32	ADF4350_PWRDOWN,
33};
34
35struct adf4350_state {
36	struct spi_device		*spi;
37	struct regulator		*reg;
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	 * DMA (thus cache coherency maintenance) requires the
53	 * transfer buffers to live in their own cache lines.
54	 */
55	__be32				val ____cacheline_aligned;
56};
57
58static struct adf4350_platform_data default_pdata = {
59	.channel_spacing = 10000,
60	.r2_user_settings = ADF4350_REG2_PD_POLARITY_POS |
61			    ADF4350_REG2_CHARGE_PUMP_CURR_uA(2500),
62	.r3_user_settings = ADF4350_REG3_12BIT_CLKDIV_MODE(0),
63	.r4_user_settings = ADF4350_REG4_OUTPUT_PWR(3) |
64			    ADF4350_REG4_MUTE_TILL_LOCK_EN,
65	.gpio_lock_detect = -1,
66};
67
68static int adf4350_sync_config(struct adf4350_state *st)
69{
70	int ret, i, doublebuf = 0;
71
72	for (i = ADF4350_REG5; i >= ADF4350_REG0; i--) {
73		if ((st->regs_hw[i] != st->regs[i]) ||
74			((i == ADF4350_REG0) && doublebuf)) {
75			switch (i) {
76			case ADF4350_REG1:
77			case ADF4350_REG4:
78				doublebuf = 1;
79				break;
80			}
81
82			st->val  = cpu_to_be32(st->regs[i] | i);
83			ret = spi_write(st->spi, &st->val, 4);
84			if (ret < 0)
85				return ret;
86			st->regs_hw[i] = st->regs[i];
87			dev_dbg(&st->spi->dev, "[%d] 0x%X\n",
88				i, (u32)st->regs[i] | i);
89		}
90	}
91	return 0;
92}
93
94static int adf4350_reg_access(struct iio_dev *indio_dev,
95			      unsigned reg, unsigned writeval,
96			      unsigned *readval)
97{
98	struct adf4350_state *st = iio_priv(indio_dev);
99	int ret;
100
101	if (reg > ADF4350_REG5)
102		return -EINVAL;
103
104	mutex_lock(&indio_dev->mlock);
105	if (readval == NULL) {
106		st->regs[reg] = writeval & ~(BIT(0) | BIT(1) | BIT(2));
107		ret = adf4350_sync_config(st);
108	} else {
109		*readval =  st->regs_hw[reg];
110		ret = 0;
111	}
112	mutex_unlock(&indio_dev->mlock);
113
114	return ret;
115}
116
117static int adf4350_tune_r_cnt(struct adf4350_state *st, unsigned short r_cnt)
118{
119	struct adf4350_platform_data *pdata = st->pdata;
120
121	do {
122		r_cnt++;
123		st->fpfd = (st->clkin * (pdata->ref_doubler_en ? 2 : 1)) /
124			   (r_cnt * (pdata->ref_div2_en ? 2 : 1));
125	} while (st->fpfd > ADF4350_MAX_FREQ_PFD);
126
127	return r_cnt;
128}
129
130static int adf4350_set_freq(struct adf4350_state *st, unsigned long long freq)
131{
132	struct adf4350_platform_data *pdata = st->pdata;
133	u64 tmp;
134	u32 div_gcd, prescaler, chspc;
135	u16 mdiv, r_cnt = 0;
136	u8 band_sel_div;
137
138	if (freq > ADF4350_MAX_OUT_FREQ || freq < st->min_out_freq)
139		return -EINVAL;
140
141	if (freq > ADF4350_MAX_FREQ_45_PRESC) {
142		prescaler = ADF4350_REG1_PRESCALER;
143		mdiv = 75;
144	} else {
145		prescaler = 0;
146		mdiv = 23;
147	}
148
149	st->r4_rf_div_sel = 0;
150
151	while (freq < ADF4350_MIN_VCO_FREQ) {
152		freq <<= 1;
153		st->r4_rf_div_sel++;
154	}
155
156	/*
157	 * Allow a predefined reference division factor
158	 * if not set, compute our own
159	 */
160	if (pdata->ref_div_factor)
161		r_cnt = pdata->ref_div_factor - 1;
162
163	chspc = st->chspc;
164
165	do  {
166		do {
167			do {
168				r_cnt = adf4350_tune_r_cnt(st, r_cnt);
169				st->r1_mod = st->fpfd / chspc;
170				if (r_cnt > ADF4350_MAX_R_CNT) {
171					/* try higher spacing values */
172					chspc++;
173					r_cnt = 0;
174				}
175			} while ((st->r1_mod > ADF4350_MAX_MODULUS) && r_cnt);
176		} while (r_cnt == 0);
177
178		tmp = freq * (u64)st->r1_mod + (st->fpfd >> 1);
179		do_div(tmp, st->fpfd); /* Div round closest (n + d/2)/d */
180		st->r0_fract = do_div(tmp, st->r1_mod);
181		st->r0_int = tmp;
182	} while (mdiv > st->r0_int);
183
184	band_sel_div = DIV_ROUND_UP(st->fpfd, ADF4350_MAX_BANDSEL_CLK);
185
186	if (st->r0_fract && st->r1_mod) {
187		div_gcd = gcd(st->r1_mod, st->r0_fract);
188		st->r1_mod /= div_gcd;
189		st->r0_fract /= div_gcd;
190	} else {
191		st->r0_fract = 0;
192		st->r1_mod = 1;
193	}
194
195	dev_dbg(&st->spi->dev, "VCO: %llu Hz, PFD %lu Hz\n"
196		"REF_DIV %d, R0_INT %d, R0_FRACT %d\n"
197		"R1_MOD %d, RF_DIV %d\nPRESCALER %s, BAND_SEL_DIV %d\n",
198		freq, st->fpfd, r_cnt, st->r0_int, st->r0_fract, st->r1_mod,
199		1 << st->r4_rf_div_sel, prescaler ? "8/9" : "4/5",
200		band_sel_div);
201
202	st->regs[ADF4350_REG0] = ADF4350_REG0_INT(st->r0_int) |
203				 ADF4350_REG0_FRACT(st->r0_fract);
204
205	st->regs[ADF4350_REG1] = ADF4350_REG1_PHASE(1) |
206				 ADF4350_REG1_MOD(st->r1_mod) |
207				 prescaler;
208
209	st->regs[ADF4350_REG2] =
210		ADF4350_REG2_10BIT_R_CNT(r_cnt) |
211		ADF4350_REG2_DOUBLE_BUFF_EN |
212		(pdata->ref_doubler_en ? ADF4350_REG2_RMULT2_EN : 0) |
213		(pdata->ref_div2_en ? ADF4350_REG2_RDIV2_EN : 0) |
214		(pdata->r2_user_settings & (ADF4350_REG2_PD_POLARITY_POS |
215		ADF4350_REG2_LDP_6ns | ADF4350_REG2_LDF_INT_N |
216		ADF4350_REG2_CHARGE_PUMP_CURR_uA(5000) |
217		ADF4350_REG2_MUXOUT(0x7) | ADF4350_REG2_NOISE_MODE(0x3)));
218
219	st->regs[ADF4350_REG3] = pdata->r3_user_settings &
220				 (ADF4350_REG3_12BIT_CLKDIV(0xFFF) |
221				 ADF4350_REG3_12BIT_CLKDIV_MODE(0x3) |
222				 ADF4350_REG3_12BIT_CSR_EN |
223				 ADF4351_REG3_CHARGE_CANCELLATION_EN |
224				 ADF4351_REG3_ANTI_BACKLASH_3ns_EN |
225				 ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH);
226
227	st->regs[ADF4350_REG4] =
228		ADF4350_REG4_FEEDBACK_FUND |
229		ADF4350_REG4_RF_DIV_SEL(st->r4_rf_div_sel) |
230		ADF4350_REG4_8BIT_BAND_SEL_CLKDIV(band_sel_div) |
231		ADF4350_REG4_RF_OUT_EN |
232		(pdata->r4_user_settings &
233		(ADF4350_REG4_OUTPUT_PWR(0x3) |
234		ADF4350_REG4_AUX_OUTPUT_PWR(0x3) |
235		ADF4350_REG4_AUX_OUTPUT_EN |
236		ADF4350_REG4_AUX_OUTPUT_FUND |
237		ADF4350_REG4_MUTE_TILL_LOCK_EN));
238
239	st->regs[ADF4350_REG5] = ADF4350_REG5_LD_PIN_MODE_DIGITAL;
240	st->freq_req = freq;
241
242	return adf4350_sync_config(st);
243}
244
245static ssize_t adf4350_write(struct iio_dev *indio_dev,
246				    uintptr_t private,
247				    const struct iio_chan_spec *chan,
248				    const char *buf, size_t len)
249{
250	struct adf4350_state *st = iio_priv(indio_dev);
251	unsigned long long readin;
252	unsigned long tmp;
253	int ret;
254
255	ret = kstrtoull(buf, 10, &readin);
256	if (ret)
257		return ret;
258
259	mutex_lock(&indio_dev->mlock);
260	switch ((u32)private) {
261	case ADF4350_FREQ:
262		ret = adf4350_set_freq(st, readin);
263		break;
264	case ADF4350_FREQ_REFIN:
265		if (readin > ADF4350_MAX_FREQ_REFIN) {
266			ret = -EINVAL;
267			break;
268		}
269
270		if (st->clk) {
271			tmp = clk_round_rate(st->clk, readin);
272			if (tmp != readin) {
273				ret = -EINVAL;
274				break;
275			}
276			ret = clk_set_rate(st->clk, tmp);
277			if (ret < 0)
278				break;
279		}
280		st->clkin = readin;
281		ret = adf4350_set_freq(st, st->freq_req);
282		break;
283	case ADF4350_FREQ_RESOLUTION:
284		if (readin == 0)
285			ret = -EINVAL;
286		else
287			st->chspc = readin;
288		break;
289	case ADF4350_PWRDOWN:
290		if (readin)
291			st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
292		else
293			st->regs[ADF4350_REG2] &= ~ADF4350_REG2_POWER_DOWN_EN;
294
295		adf4350_sync_config(st);
296		break;
297	default:
298		ret = -EINVAL;
299	}
300	mutex_unlock(&indio_dev->mlock);
301
302	return ret ? ret : len;
303}
304
305static ssize_t adf4350_read(struct iio_dev *indio_dev,
306				   uintptr_t private,
307				   const struct iio_chan_spec *chan,
308				   char *buf)
309{
310	struct adf4350_state *st = iio_priv(indio_dev);
311	unsigned long long val;
312	int ret = 0;
313
314	mutex_lock(&indio_dev->mlock);
315	switch ((u32)private) {
316	case ADF4350_FREQ:
317		val = (u64)((st->r0_int * st->r1_mod) + st->r0_fract) *
318			(u64)st->fpfd;
319		do_div(val, st->r1_mod * (1 << st->r4_rf_div_sel));
320		/* PLL unlocked? return error */
321		if (gpio_is_valid(st->pdata->gpio_lock_detect))
322			if (!gpio_get_value(st->pdata->gpio_lock_detect)) {
323				dev_dbg(&st->spi->dev, "PLL un-locked\n");
324				ret = -EBUSY;
325			}
326		break;
327	case ADF4350_FREQ_REFIN:
328		if (st->clk)
329			st->clkin = clk_get_rate(st->clk);
330
331		val = st->clkin;
332		break;
333	case ADF4350_FREQ_RESOLUTION:
334		val = st->chspc;
335		break;
336	case ADF4350_PWRDOWN:
337		val = !!(st->regs[ADF4350_REG2] & ADF4350_REG2_POWER_DOWN_EN);
338		break;
339	default:
340		ret = -EINVAL;
341		val = 0;
342	}
343	mutex_unlock(&indio_dev->mlock);
344
345	return ret < 0 ? ret : sprintf(buf, "%llu\n", val);
346}
347
348#define _ADF4350_EXT_INFO(_name, _ident) { \
349	.name = _name, \
350	.read = adf4350_read, \
351	.write = adf4350_write, \
352	.private = _ident, \
353	.shared = IIO_SEPARATE, \
354}
355
356static const struct iio_chan_spec_ext_info adf4350_ext_info[] = {
357	/* Ideally we use IIO_CHAN_INFO_FREQUENCY, but there are
358	 * values > 2^32 in order to support the entire frequency range
359	 * in Hz. Using scale is a bit ugly.
360	 */
361	_ADF4350_EXT_INFO("frequency", ADF4350_FREQ),
362	_ADF4350_EXT_INFO("frequency_resolution", ADF4350_FREQ_RESOLUTION),
363	_ADF4350_EXT_INFO("refin_frequency", ADF4350_FREQ_REFIN),
364	_ADF4350_EXT_INFO("powerdown", ADF4350_PWRDOWN),
365	{ },
366};
367
368static const struct iio_chan_spec adf4350_chan = {
369	.type = IIO_ALTVOLTAGE,
370	.indexed = 1,
371	.output = 1,
372	.ext_info = adf4350_ext_info,
373};
374
375static const struct iio_info adf4350_info = {
376	.debugfs_reg_access = &adf4350_reg_access,
377	.driver_module = THIS_MODULE,
378};
379
380#ifdef CONFIG_OF
381static struct adf4350_platform_data *adf4350_parse_dt(struct device *dev)
382{
383	struct device_node *np = dev->of_node;
384	struct adf4350_platform_data *pdata;
385	unsigned int tmp;
386	int ret;
387
388	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
389	if (!pdata)
390		return NULL;
391
392	strncpy(&pdata->name[0], np->name, SPI_NAME_SIZE - 1);
393
394	tmp = 10000;
395	of_property_read_u32(np, "adi,channel-spacing", &tmp);
396	pdata->channel_spacing = tmp;
397
398	tmp = 0;
399	of_property_read_u32(np, "adi,power-up-frequency", &tmp);
400	pdata->power_up_frequency = tmp;
401
402	tmp = 0;
403	of_property_read_u32(np, "adi,reference-div-factor", &tmp);
404	pdata->ref_div_factor = tmp;
405
406	ret = of_get_gpio(np, 0);
407	if (ret < 0)
408		pdata->gpio_lock_detect = -1;
409	else
410		pdata->gpio_lock_detect = ret;
411
412	pdata->ref_doubler_en = of_property_read_bool(np,
413			"adi,reference-doubler-enable");
414	pdata->ref_div2_en = of_property_read_bool(np,
415			"adi,reference-div2-enable");
416
417	/* r2_user_settings */
418	pdata->r2_user_settings = of_property_read_bool(np,
419			"adi,phase-detector-polarity-positive-enable") ?
420			ADF4350_REG2_PD_POLARITY_POS : 0;
421	pdata->r2_user_settings |= of_property_read_bool(np,
422			"adi,lock-detect-precision-6ns-enable") ?
423			ADF4350_REG2_LDP_6ns : 0;
424	pdata->r2_user_settings |= of_property_read_bool(np,
425			"adi,lock-detect-function-integer-n-enable") ?
426			ADF4350_REG2_LDF_INT_N : 0;
427
428	tmp = 2500;
429	of_property_read_u32(np, "adi,charge-pump-current", &tmp);
430	pdata->r2_user_settings |= ADF4350_REG2_CHARGE_PUMP_CURR_uA(tmp);
431
432	tmp = 0;
433	of_property_read_u32(np, "adi,muxout-select", &tmp);
434	pdata->r2_user_settings |= ADF4350_REG2_MUXOUT(tmp);
435
436	pdata->r2_user_settings |= of_property_read_bool(np,
437			"adi,low-spur-mode-enable") ?
438			ADF4350_REG2_NOISE_MODE(0x3) : 0;
439
440	/* r3_user_settings */
441
442	pdata->r3_user_settings = of_property_read_bool(np,
443			"adi,cycle-slip-reduction-enable") ?
444			ADF4350_REG3_12BIT_CSR_EN : 0;
445	pdata->r3_user_settings |= of_property_read_bool(np,
446			"adi,charge-cancellation-enable") ?
447			ADF4351_REG3_CHARGE_CANCELLATION_EN : 0;
448
449	pdata->r3_user_settings |= of_property_read_bool(np,
450			"adi,anti-backlash-3ns-enable") ?
451			ADF4351_REG3_ANTI_BACKLASH_3ns_EN : 0;
452	pdata->r3_user_settings |= of_property_read_bool(np,
453			"adi,band-select-clock-mode-high-enable") ?
454			ADF4351_REG3_BAND_SEL_CLOCK_MODE_HIGH : 0;
455
456	tmp = 0;
457	of_property_read_u32(np, "adi,12bit-clk-divider", &tmp);
458	pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV(tmp);
459
460	tmp = 0;
461	of_property_read_u32(np, "adi,clk-divider-mode", &tmp);
462	pdata->r3_user_settings |= ADF4350_REG3_12BIT_CLKDIV_MODE(tmp);
463
464	/* r4_user_settings */
465
466	pdata->r4_user_settings = of_property_read_bool(np,
467			"adi,aux-output-enable") ?
468			ADF4350_REG4_AUX_OUTPUT_EN : 0;
469	pdata->r4_user_settings |= of_property_read_bool(np,
470			"adi,aux-output-fundamental-enable") ?
471			ADF4350_REG4_AUX_OUTPUT_FUND : 0;
472	pdata->r4_user_settings |= of_property_read_bool(np,
473			"adi,mute-till-lock-enable") ?
474			ADF4350_REG4_MUTE_TILL_LOCK_EN : 0;
475
476	tmp = 0;
477	of_property_read_u32(np, "adi,output-power", &tmp);
478	pdata->r4_user_settings |= ADF4350_REG4_OUTPUT_PWR(tmp);
479
480	tmp = 0;
481	of_property_read_u32(np, "adi,aux-output-power", &tmp);
482	pdata->r4_user_settings |= ADF4350_REG4_AUX_OUTPUT_PWR(tmp);
483
484	return pdata;
485}
486#else
487static
488struct adf4350_platform_data *adf4350_parse_dt(struct device *dev)
489{
490	return NULL;
491}
492#endif
493
494static int adf4350_probe(struct spi_device *spi)
495{
496	struct adf4350_platform_data *pdata;
497	struct iio_dev *indio_dev;
498	struct adf4350_state *st;
499	struct clk *clk = NULL;
500	int ret;
501
502	if (spi->dev.of_node) {
503		pdata = adf4350_parse_dt(&spi->dev);
504		if (pdata == NULL)
505			return -EINVAL;
506	} else {
507		pdata = spi->dev.platform_data;
508	}
509
510	if (!pdata) {
511		dev_warn(&spi->dev, "no platform data? using default\n");
512		pdata = &default_pdata;
513	}
514
515	if (!pdata->clkin) {
516		clk = devm_clk_get(&spi->dev, "clkin");
517		if (IS_ERR(clk))
518			return -EPROBE_DEFER;
519
520		ret = clk_prepare_enable(clk);
521		if (ret < 0)
522			return ret;
523	}
524
525	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
526	if (indio_dev == NULL) {
527		ret =  -ENOMEM;
528		goto error_disable_clk;
529	}
530
531	st = iio_priv(indio_dev);
532
533	st->reg = devm_regulator_get(&spi->dev, "vcc");
534	if (!IS_ERR(st->reg)) {
535		ret = regulator_enable(st->reg);
536		if (ret)
537			goto error_disable_clk;
538	}
539
540	spi_set_drvdata(spi, indio_dev);
541	st->spi = spi;
542	st->pdata = pdata;
543
544	indio_dev->dev.parent = &spi->dev;
545	indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
546		spi_get_device_id(spi)->name;
547
548	indio_dev->info = &adf4350_info;
549	indio_dev->modes = INDIO_DIRECT_MODE;
550	indio_dev->channels = &adf4350_chan;
551	indio_dev->num_channels = 1;
552
553	st->chspc = pdata->channel_spacing;
554	if (clk) {
555		st->clk = clk;
556		st->clkin = clk_get_rate(clk);
557	} else {
558		st->clkin = pdata->clkin;
559	}
560
561	st->min_out_freq = spi_get_device_id(spi)->driver_data == 4351 ?
562		ADF4351_MIN_OUT_FREQ : ADF4350_MIN_OUT_FREQ;
563
564	memset(st->regs_hw, 0xFF, sizeof(st->regs_hw));
565
566	if (gpio_is_valid(pdata->gpio_lock_detect)) {
567		ret = devm_gpio_request(&spi->dev, pdata->gpio_lock_detect,
568					indio_dev->name);
569		if (ret) {
570			dev_err(&spi->dev, "fail to request lock detect GPIO-%d",
571				pdata->gpio_lock_detect);
572			goto error_disable_reg;
573		}
574		gpio_direction_input(pdata->gpio_lock_detect);
575	}
576
577	if (pdata->power_up_frequency) {
578		ret = adf4350_set_freq(st, pdata->power_up_frequency);
579		if (ret)
580			goto error_disable_reg;
581	}
582
583	ret = iio_device_register(indio_dev);
584	if (ret)
585		goto error_disable_reg;
586
587	return 0;
588
589error_disable_reg:
590	if (!IS_ERR(st->reg))
591		regulator_disable(st->reg);
592error_disable_clk:
593	if (clk)
594		clk_disable_unprepare(clk);
595
596	return ret;
597}
598
599static int adf4350_remove(struct spi_device *spi)
600{
601	struct iio_dev *indio_dev = spi_get_drvdata(spi);
602	struct adf4350_state *st = iio_priv(indio_dev);
603	struct regulator *reg = st->reg;
604
605	st->regs[ADF4350_REG2] |= ADF4350_REG2_POWER_DOWN_EN;
606	adf4350_sync_config(st);
607
608	iio_device_unregister(indio_dev);
609
610	if (st->clk)
611		clk_disable_unprepare(st->clk);
612
613	if (!IS_ERR(reg))
614		regulator_disable(reg);
615
616	return 0;
617}
618
619static const struct of_device_id adf4350_of_match[] = {
620	{ .compatible = "adi,adf4350", },
621	{ .compatible = "adi,adf4351", },
622	{ /* sentinel */ },
623};
624MODULE_DEVICE_TABLE(of, adf4350_of_match);
625
626static const struct spi_device_id adf4350_id[] = {
627	{"adf4350", 4350},
628	{"adf4351", 4351},
629	{}
630};
631MODULE_DEVICE_TABLE(spi, adf4350_id);
632
633static struct spi_driver adf4350_driver = {
634	.driver = {
635		.name	= "adf4350",
636		.of_match_table = of_match_ptr(adf4350_of_match),
637	},
638	.probe		= adf4350_probe,
639	.remove		= adf4350_remove,
640	.id_table	= adf4350_id,
641};
642module_spi_driver(adf4350_driver);
643
644MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
645MODULE_DESCRIPTION("Analog Devices ADF4350/ADF4351 PLL");
646MODULE_LICENSE("GPL v2");
647