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
adf4350_sync_config(struct adf4350_state * st)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
adf4350_reg_access(struct iio_dev * indio_dev,unsigned reg,unsigned writeval,unsigned * readval)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
adf4350_tune_r_cnt(struct adf4350_state * st,unsigned short r_cnt)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
adf4350_set_freq(struct adf4350_state * st,unsigned long long freq)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
adf4350_write(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)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
adf4350_read(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)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
adf4350_parse_dt(struct device * dev)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
adf4350_power_down(void * data)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
adf4350_probe(struct spi_device * spi)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