xref: /linux/drivers/iio/filter/admv8818.c (revision a1c613ae4c322ddd58d5a8539dbfba2a0380a8c0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ADMV8818 driver
4  *
5  * Copyright 2021 Analog Devices Inc.
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/bits.h>
10 #include <linux/clk.h>
11 #include <linux/device.h>
12 #include <linux/iio/iio.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/mutex.h>
16 #include <linux/notifier.h>
17 #include <linux/regmap.h>
18 #include <linux/spi/spi.h>
19 #include <linux/units.h>
20 
21 /* ADMV8818 Register Map */
22 #define ADMV8818_REG_SPI_CONFIG_A		0x0
23 #define ADMV8818_REG_SPI_CONFIG_B		0x1
24 #define ADMV8818_REG_CHIPTYPE			0x3
25 #define ADMV8818_REG_PRODUCT_ID_L		0x4
26 #define ADMV8818_REG_PRODUCT_ID_H		0x5
27 #define ADMV8818_REG_FAST_LATCH_POINTER		0x10
28 #define ADMV8818_REG_FAST_LATCH_STOP		0x11
29 #define ADMV8818_REG_FAST_LATCH_START		0x12
30 #define ADMV8818_REG_FAST_LATCH_DIRECTION	0x13
31 #define ADMV8818_REG_FAST_LATCH_STATE		0x14
32 #define ADMV8818_REG_WR0_SW			0x20
33 #define ADMV8818_REG_WR0_FILTER			0x21
34 #define ADMV8818_REG_WR1_SW			0x22
35 #define ADMV8818_REG_WR1_FILTER			0x23
36 #define ADMV8818_REG_WR2_SW			0x24
37 #define ADMV8818_REG_WR2_FILTER			0x25
38 #define ADMV8818_REG_WR3_SW			0x26
39 #define ADMV8818_REG_WR3_FILTER			0x27
40 #define ADMV8818_REG_WR4_SW			0x28
41 #define ADMV8818_REG_WR4_FILTER			0x29
42 #define ADMV8818_REG_LUT0_SW			0x100
43 #define ADMV8818_REG_LUT0_FILTER		0x101
44 #define ADMV8818_REG_LUT127_SW			0x1FE
45 #define ADMV8818_REG_LUT127_FILTER		0x1FF
46 
47 /* ADMV8818_REG_SPI_CONFIG_A Map */
48 #define ADMV8818_SOFTRESET_N_MSK		BIT(7)
49 #define ADMV8818_LSB_FIRST_N_MSK		BIT(6)
50 #define ADMV8818_ENDIAN_N_MSK			BIT(5)
51 #define ADMV8818_SDOACTIVE_N_MSK		BIT(4)
52 #define ADMV8818_SDOACTIVE_MSK			BIT(3)
53 #define ADMV8818_ENDIAN_MSK			BIT(2)
54 #define ADMV8818_LSBFIRST_MSK			BIT(1)
55 #define ADMV8818_SOFTRESET_MSK			BIT(0)
56 
57 /* ADMV8818_REG_SPI_CONFIG_B Map */
58 #define ADMV8818_SINGLE_INSTRUCTION_MSK		BIT(7)
59 #define ADMV8818_CSB_STALL_MSK			BIT(6)
60 #define ADMV8818_MASTER_SLAVE_RB_MSK		BIT(5)
61 #define ADMV8818_MASTER_SLAVE_TRANSFER_MSK	BIT(0)
62 
63 /* ADMV8818_REG_WR0_SW Map */
64 #define ADMV8818_SW_IN_SET_WR0_MSK		BIT(7)
65 #define ADMV8818_SW_OUT_SET_WR0_MSK		BIT(6)
66 #define ADMV8818_SW_IN_WR0_MSK			GENMASK(5, 3)
67 #define ADMV8818_SW_OUT_WR0_MSK			GENMASK(2, 0)
68 
69 /* ADMV8818_REG_WR0_FILTER Map */
70 #define ADMV8818_HPF_WR0_MSK			GENMASK(7, 4)
71 #define ADMV8818_LPF_WR0_MSK			GENMASK(3, 0)
72 
73 enum {
74 	ADMV8818_BW_FREQ,
75 	ADMV8818_CENTER_FREQ
76 };
77 
78 enum {
79 	ADMV8818_AUTO_MODE,
80 	ADMV8818_MANUAL_MODE,
81 	ADMV8818_BYPASS_MODE,
82 };
83 
84 struct admv8818_state {
85 	struct spi_device	*spi;
86 	struct regmap		*regmap;
87 	struct clk		*clkin;
88 	struct notifier_block	nb;
89 	/* Protect against concurrent accesses to the device and data content*/
90 	struct mutex		lock;
91 	unsigned int		filter_mode;
92 	u64			cf_hz;
93 };
94 
95 static const unsigned long long freq_range_hpf[4][2] = {
96 	{1750000000ULL, 3550000000ULL},
97 	{3400000000ULL, 7250000000ULL},
98 	{6600000000, 12000000000},
99 	{12500000000, 19900000000}
100 };
101 
102 static const unsigned long long freq_range_lpf[4][2] = {
103 	{2050000000ULL, 3850000000ULL},
104 	{3350000000ULL, 7250000000ULL},
105 	{7000000000, 13000000000},
106 	{12550000000, 18500000000}
107 };
108 
109 static const struct regmap_config admv8818_regmap_config = {
110 	.reg_bits = 16,
111 	.val_bits = 8,
112 	.read_flag_mask = 0x80,
113 	.max_register = 0x1FF,
114 };
115 
116 static const char * const admv8818_modes[] = {
117 	[0] = "auto",
118 	[1] = "manual",
119 	[2] = "bypass"
120 };
121 
__admv8818_hpf_select(struct admv8818_state * st,u64 freq)122 static int __admv8818_hpf_select(struct admv8818_state *st, u64 freq)
123 {
124 	unsigned int hpf_step = 0, hpf_band = 0, i, j;
125 	u64 freq_step;
126 	int ret;
127 
128 	if (freq < freq_range_hpf[0][0])
129 		goto hpf_write;
130 
131 	if (freq > freq_range_hpf[3][1]) {
132 		hpf_step = 15;
133 		hpf_band = 4;
134 
135 		goto hpf_write;
136 	}
137 
138 	for (i = 0; i < 4; i++) {
139 		freq_step = div_u64((freq_range_hpf[i][1] -
140 			freq_range_hpf[i][0]), 15);
141 
142 		if (freq > freq_range_hpf[i][0] &&
143 		    (freq < freq_range_hpf[i][1] + freq_step)) {
144 			hpf_band = i + 1;
145 
146 			for (j = 1; j <= 16; j++) {
147 				if (freq < (freq_range_hpf[i][0] + (freq_step * j))) {
148 					hpf_step = j - 1;
149 					break;
150 				}
151 			}
152 			break;
153 		}
154 	}
155 
156 	/* Close HPF frequency gap between 12 and 12.5 GHz */
157 	if (freq >= 12000 * HZ_PER_MHZ && freq <= 12500 * HZ_PER_MHZ) {
158 		hpf_band = 3;
159 		hpf_step = 15;
160 	}
161 
162 hpf_write:
163 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_WR0_SW,
164 				 ADMV8818_SW_IN_SET_WR0_MSK |
165 				 ADMV8818_SW_IN_WR0_MSK,
166 				 FIELD_PREP(ADMV8818_SW_IN_SET_WR0_MSK, 1) |
167 				 FIELD_PREP(ADMV8818_SW_IN_WR0_MSK, hpf_band));
168 	if (ret)
169 		return ret;
170 
171 	return regmap_update_bits(st->regmap, ADMV8818_REG_WR0_FILTER,
172 				  ADMV8818_HPF_WR0_MSK,
173 				  FIELD_PREP(ADMV8818_HPF_WR0_MSK, hpf_step));
174 }
175 
admv8818_hpf_select(struct admv8818_state * st,u64 freq)176 static int admv8818_hpf_select(struct admv8818_state *st, u64 freq)
177 {
178 	int ret;
179 
180 	mutex_lock(&st->lock);
181 	ret = __admv8818_hpf_select(st, freq);
182 	mutex_unlock(&st->lock);
183 
184 	return ret;
185 }
186 
__admv8818_lpf_select(struct admv8818_state * st,u64 freq)187 static int __admv8818_lpf_select(struct admv8818_state *st, u64 freq)
188 {
189 	unsigned int lpf_step = 0, lpf_band = 0, i, j;
190 	u64 freq_step;
191 	int ret;
192 
193 	if (freq > freq_range_lpf[3][1])
194 		goto lpf_write;
195 
196 	if (freq < freq_range_lpf[0][0]) {
197 		lpf_band = 1;
198 
199 		goto lpf_write;
200 	}
201 
202 	for (i = 0; i < 4; i++) {
203 		if (freq > freq_range_lpf[i][0] && freq < freq_range_lpf[i][1]) {
204 			lpf_band = i + 1;
205 			freq_step = div_u64((freq_range_lpf[i][1] - freq_range_lpf[i][0]), 15);
206 
207 			for (j = 0; j <= 15; j++) {
208 				if (freq < (freq_range_lpf[i][0] + (freq_step * j))) {
209 					lpf_step = j;
210 					break;
211 				}
212 			}
213 			break;
214 		}
215 	}
216 
217 lpf_write:
218 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_WR0_SW,
219 				 ADMV8818_SW_OUT_SET_WR0_MSK |
220 				 ADMV8818_SW_OUT_WR0_MSK,
221 				 FIELD_PREP(ADMV8818_SW_OUT_SET_WR0_MSK, 1) |
222 				 FIELD_PREP(ADMV8818_SW_OUT_WR0_MSK, lpf_band));
223 	if (ret)
224 		return ret;
225 
226 	return regmap_update_bits(st->regmap, ADMV8818_REG_WR0_FILTER,
227 				  ADMV8818_LPF_WR0_MSK,
228 				  FIELD_PREP(ADMV8818_LPF_WR0_MSK, lpf_step));
229 }
230 
admv8818_lpf_select(struct admv8818_state * st,u64 freq)231 static int admv8818_lpf_select(struct admv8818_state *st, u64 freq)
232 {
233 	int ret;
234 
235 	mutex_lock(&st->lock);
236 	ret = __admv8818_lpf_select(st, freq);
237 	mutex_unlock(&st->lock);
238 
239 	return ret;
240 }
241 
admv8818_rfin_band_select(struct admv8818_state * st)242 static int admv8818_rfin_band_select(struct admv8818_state *st)
243 {
244 	int ret;
245 
246 	st->cf_hz = clk_get_rate(st->clkin);
247 
248 	mutex_lock(&st->lock);
249 
250 	ret = __admv8818_hpf_select(st, st->cf_hz);
251 	if (ret)
252 		goto exit;
253 
254 	ret = __admv8818_lpf_select(st, st->cf_hz);
255 exit:
256 	mutex_unlock(&st->lock);
257 	return ret;
258 }
259 
__admv8818_read_hpf_freq(struct admv8818_state * st,u64 * hpf_freq)260 static int __admv8818_read_hpf_freq(struct admv8818_state *st, u64 *hpf_freq)
261 {
262 	unsigned int data, hpf_band, hpf_state;
263 	int ret;
264 
265 	ret = regmap_read(st->regmap, ADMV8818_REG_WR0_SW, &data);
266 	if (ret)
267 		return ret;
268 
269 	hpf_band = FIELD_GET(ADMV8818_SW_IN_WR0_MSK, data);
270 	if (!hpf_band || hpf_band > 4) {
271 		*hpf_freq = 0;
272 		return ret;
273 	}
274 
275 	ret = regmap_read(st->regmap, ADMV8818_REG_WR0_FILTER, &data);
276 	if (ret)
277 		return ret;
278 
279 	hpf_state = FIELD_GET(ADMV8818_HPF_WR0_MSK, data);
280 
281 	*hpf_freq = div_u64(freq_range_hpf[hpf_band - 1][1] - freq_range_hpf[hpf_band - 1][0], 15);
282 	*hpf_freq = freq_range_hpf[hpf_band - 1][0] + (*hpf_freq * hpf_state);
283 
284 	return ret;
285 }
286 
admv8818_read_hpf_freq(struct admv8818_state * st,u64 * hpf_freq)287 static int admv8818_read_hpf_freq(struct admv8818_state *st, u64 *hpf_freq)
288 {
289 	int ret;
290 
291 	mutex_lock(&st->lock);
292 	ret = __admv8818_read_hpf_freq(st, hpf_freq);
293 	mutex_unlock(&st->lock);
294 
295 	return ret;
296 }
297 
__admv8818_read_lpf_freq(struct admv8818_state * st,u64 * lpf_freq)298 static int __admv8818_read_lpf_freq(struct admv8818_state *st, u64 *lpf_freq)
299 {
300 	unsigned int data, lpf_band, lpf_state;
301 	int ret;
302 
303 	ret = regmap_read(st->regmap, ADMV8818_REG_WR0_SW, &data);
304 	if (ret)
305 		return ret;
306 
307 	lpf_band = FIELD_GET(ADMV8818_SW_OUT_WR0_MSK, data);
308 	if (!lpf_band || lpf_band > 4) {
309 		*lpf_freq = 0;
310 		return ret;
311 	}
312 
313 	ret = regmap_read(st->regmap, ADMV8818_REG_WR0_FILTER, &data);
314 	if (ret)
315 		return ret;
316 
317 	lpf_state = FIELD_GET(ADMV8818_LPF_WR0_MSK, data);
318 
319 	*lpf_freq = div_u64(freq_range_lpf[lpf_band - 1][1] - freq_range_lpf[lpf_band - 1][0], 15);
320 	*lpf_freq = freq_range_lpf[lpf_band - 1][0] + (*lpf_freq * lpf_state);
321 
322 	return ret;
323 }
324 
admv8818_read_lpf_freq(struct admv8818_state * st,u64 * lpf_freq)325 static int admv8818_read_lpf_freq(struct admv8818_state *st, u64 *lpf_freq)
326 {
327 	int ret;
328 
329 	mutex_lock(&st->lock);
330 	ret = __admv8818_read_lpf_freq(st, lpf_freq);
331 	mutex_unlock(&st->lock);
332 
333 	return ret;
334 }
335 
admv8818_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long info)336 static int admv8818_write_raw(struct iio_dev *indio_dev,
337 			      struct iio_chan_spec const *chan,
338 			      int val, int val2, long info)
339 {
340 	struct admv8818_state *st = iio_priv(indio_dev);
341 
342 	u64 freq = ((u64)val2 << 32 | (u32)val);
343 
344 	switch (info) {
345 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
346 		return admv8818_lpf_select(st, freq);
347 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
348 		return admv8818_hpf_select(st, freq);
349 	default:
350 		return -EINVAL;
351 	}
352 }
353 
admv8818_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long info)354 static int admv8818_read_raw(struct iio_dev *indio_dev,
355 			     struct iio_chan_spec const *chan,
356 			     int *val, int *val2, long info)
357 {
358 	struct admv8818_state *st = iio_priv(indio_dev);
359 	int ret;
360 	u64 freq;
361 
362 	switch (info) {
363 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
364 		ret = admv8818_read_lpf_freq(st, &freq);
365 		if (ret)
366 			return ret;
367 
368 		*val = (u32)freq;
369 		*val2 = (u32)(freq >> 32);
370 
371 		return IIO_VAL_INT_64;
372 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
373 		ret = admv8818_read_hpf_freq(st, &freq);
374 		if (ret)
375 			return ret;
376 
377 		*val = (u32)freq;
378 		*val2 = (u32)(freq >> 32);
379 
380 		return IIO_VAL_INT_64;
381 	default:
382 		return -EINVAL;
383 	}
384 }
385 
admv8818_reg_access(struct iio_dev * indio_dev,unsigned int reg,unsigned int write_val,unsigned int * read_val)386 static int admv8818_reg_access(struct iio_dev *indio_dev,
387 			       unsigned int reg,
388 			       unsigned int write_val,
389 			       unsigned int *read_val)
390 {
391 	struct admv8818_state *st = iio_priv(indio_dev);
392 
393 	if (read_val)
394 		return regmap_read(st->regmap, reg, read_val);
395 	else
396 		return regmap_write(st->regmap, reg, write_val);
397 }
398 
admv8818_filter_bypass(struct admv8818_state * st)399 static int admv8818_filter_bypass(struct admv8818_state *st)
400 {
401 	int ret;
402 
403 	mutex_lock(&st->lock);
404 
405 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_WR0_SW,
406 				 ADMV8818_SW_IN_SET_WR0_MSK |
407 				 ADMV8818_SW_IN_WR0_MSK |
408 				 ADMV8818_SW_OUT_SET_WR0_MSK |
409 				 ADMV8818_SW_OUT_WR0_MSK,
410 				 FIELD_PREP(ADMV8818_SW_IN_SET_WR0_MSK, 1) |
411 				 FIELD_PREP(ADMV8818_SW_IN_WR0_MSK, 0) |
412 				 FIELD_PREP(ADMV8818_SW_OUT_SET_WR0_MSK, 1) |
413 				 FIELD_PREP(ADMV8818_SW_OUT_WR0_MSK, 0));
414 	if (ret)
415 		goto exit;
416 
417 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_WR0_FILTER,
418 				 ADMV8818_HPF_WR0_MSK |
419 				 ADMV8818_LPF_WR0_MSK,
420 				 FIELD_PREP(ADMV8818_HPF_WR0_MSK, 0) |
421 				 FIELD_PREP(ADMV8818_LPF_WR0_MSK, 0));
422 
423 exit:
424 	mutex_unlock(&st->lock);
425 
426 	return ret;
427 }
428 
admv8818_get_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)429 static int admv8818_get_mode(struct iio_dev *indio_dev,
430 			     const struct iio_chan_spec *chan)
431 {
432 	struct admv8818_state *st = iio_priv(indio_dev);
433 
434 	return st->filter_mode;
435 }
436 
admv8818_set_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)437 static int admv8818_set_mode(struct iio_dev *indio_dev,
438 			     const struct iio_chan_spec *chan,
439 			     unsigned int mode)
440 {
441 	struct admv8818_state *st = iio_priv(indio_dev);
442 	int ret = 0;
443 
444 	if (!st->clkin) {
445 		if (mode == ADMV8818_MANUAL_MODE)
446 			goto set_mode;
447 
448 		if (mode == ADMV8818_BYPASS_MODE) {
449 			ret = admv8818_filter_bypass(st);
450 			if (ret)
451 				return ret;
452 
453 			goto set_mode;
454 		}
455 
456 		return -EINVAL;
457 	}
458 
459 	switch (mode) {
460 	case ADMV8818_AUTO_MODE:
461 		if (st->filter_mode == ADMV8818_AUTO_MODE)
462 			return 0;
463 
464 		ret = clk_prepare_enable(st->clkin);
465 		if (ret)
466 			return ret;
467 
468 		ret = clk_notifier_register(st->clkin, &st->nb);
469 		if (ret) {
470 			clk_disable_unprepare(st->clkin);
471 
472 			return ret;
473 		}
474 
475 		break;
476 	case ADMV8818_MANUAL_MODE:
477 	case ADMV8818_BYPASS_MODE:
478 		if (st->filter_mode == ADMV8818_AUTO_MODE) {
479 			clk_disable_unprepare(st->clkin);
480 
481 			ret = clk_notifier_unregister(st->clkin, &st->nb);
482 			if (ret)
483 				return ret;
484 		}
485 
486 		if (mode == ADMV8818_BYPASS_MODE) {
487 			ret = admv8818_filter_bypass(st);
488 			if (ret)
489 				return ret;
490 		}
491 
492 		break;
493 	default:
494 		return -EINVAL;
495 	}
496 
497 set_mode:
498 	st->filter_mode = mode;
499 
500 	return ret;
501 }
502 
503 static const struct iio_info admv8818_info = {
504 	.write_raw = admv8818_write_raw,
505 	.read_raw = admv8818_read_raw,
506 	.debugfs_reg_access = &admv8818_reg_access,
507 };
508 
509 static const struct iio_enum admv8818_mode_enum = {
510 	.items = admv8818_modes,
511 	.num_items = ARRAY_SIZE(admv8818_modes),
512 	.get = admv8818_get_mode,
513 	.set = admv8818_set_mode,
514 };
515 
516 static const struct iio_chan_spec_ext_info admv8818_ext_info[] = {
517 	IIO_ENUM("filter_mode", IIO_SHARED_BY_ALL, &admv8818_mode_enum),
518 	IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_ALL, &admv8818_mode_enum),
519 	{ },
520 };
521 
522 #define ADMV8818_CHAN(_channel) {				\
523 	.type = IIO_ALTVOLTAGE,					\
524 	.output = 1,						\
525 	.indexed = 1,						\
526 	.channel = _channel,					\
527 	.info_mask_separate =					\
528 		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
529 		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY) \
530 }
531 
532 #define ADMV8818_CHAN_BW_CF(_channel, _admv8818_ext_info) {	\
533 	.type = IIO_ALTVOLTAGE,					\
534 	.output = 1,						\
535 	.indexed = 1,						\
536 	.channel = _channel,					\
537 	.ext_info = _admv8818_ext_info,				\
538 }
539 
540 static const struct iio_chan_spec admv8818_channels[] = {
541 	ADMV8818_CHAN(0),
542 	ADMV8818_CHAN_BW_CF(0, admv8818_ext_info),
543 };
544 
admv8818_freq_change(struct notifier_block * nb,unsigned long action,void * data)545 static int admv8818_freq_change(struct notifier_block *nb, unsigned long action, void *data)
546 {
547 	struct admv8818_state *st = container_of(nb, struct admv8818_state, nb);
548 
549 	if (action == POST_RATE_CHANGE)
550 		return notifier_from_errno(admv8818_rfin_band_select(st));
551 
552 	return NOTIFY_OK;
553 }
554 
admv8818_clk_notifier_unreg(void * data)555 static void admv8818_clk_notifier_unreg(void *data)
556 {
557 	struct admv8818_state *st = data;
558 
559 	if (st->filter_mode == 0)
560 		clk_notifier_unregister(st->clkin, &st->nb);
561 }
562 
admv8818_clk_disable(void * data)563 static void admv8818_clk_disable(void *data)
564 {
565 	struct admv8818_state *st = data;
566 
567 	if (st->filter_mode == 0)
568 		clk_disable_unprepare(st->clkin);
569 }
570 
admv8818_init(struct admv8818_state * st)571 static int admv8818_init(struct admv8818_state *st)
572 {
573 	int ret;
574 	struct spi_device *spi = st->spi;
575 	unsigned int chip_id;
576 
577 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
578 				 ADMV8818_SOFTRESET_N_MSK |
579 				 ADMV8818_SOFTRESET_MSK,
580 				 FIELD_PREP(ADMV8818_SOFTRESET_N_MSK, 1) |
581 				 FIELD_PREP(ADMV8818_SOFTRESET_MSK, 1));
582 	if (ret) {
583 		dev_err(&spi->dev, "ADMV8818 Soft Reset failed.\n");
584 		return ret;
585 	}
586 
587 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_SPI_CONFIG_A,
588 				 ADMV8818_SDOACTIVE_N_MSK |
589 				 ADMV8818_SDOACTIVE_MSK,
590 				 FIELD_PREP(ADMV8818_SDOACTIVE_N_MSK, 1) |
591 				 FIELD_PREP(ADMV8818_SDOACTIVE_MSK, 1));
592 	if (ret) {
593 		dev_err(&spi->dev, "ADMV8818 SDO Enable failed.\n");
594 		return ret;
595 	}
596 
597 	ret = regmap_read(st->regmap, ADMV8818_REG_CHIPTYPE, &chip_id);
598 	if (ret) {
599 		dev_err(&spi->dev, "ADMV8818 Chip ID read failed.\n");
600 		return ret;
601 	}
602 
603 	if (chip_id != 0x1) {
604 		dev_err(&spi->dev, "ADMV8818 Invalid Chip ID.\n");
605 		return -EINVAL;
606 	}
607 
608 	ret = regmap_update_bits(st->regmap, ADMV8818_REG_SPI_CONFIG_B,
609 				 ADMV8818_SINGLE_INSTRUCTION_MSK,
610 				 FIELD_PREP(ADMV8818_SINGLE_INSTRUCTION_MSK, 1));
611 	if (ret) {
612 		dev_err(&spi->dev, "ADMV8818 Single Instruction failed.\n");
613 		return ret;
614 	}
615 
616 	if (st->clkin)
617 		return admv8818_rfin_band_select(st);
618 	else
619 		return 0;
620 }
621 
admv8818_clk_setup(struct admv8818_state * st)622 static int admv8818_clk_setup(struct admv8818_state *st)
623 {
624 	struct spi_device *spi = st->spi;
625 	int ret;
626 
627 	st->clkin = devm_clk_get_optional(&spi->dev, "rf_in");
628 	if (IS_ERR(st->clkin))
629 		return dev_err_probe(&spi->dev, PTR_ERR(st->clkin),
630 				     "failed to get the input clock\n");
631 	else if (!st->clkin)
632 		return 0;
633 
634 	ret = clk_prepare_enable(st->clkin);
635 	if (ret)
636 		return ret;
637 
638 	ret = devm_add_action_or_reset(&spi->dev, admv8818_clk_disable, st);
639 	if (ret)
640 		return ret;
641 
642 	st->nb.notifier_call = admv8818_freq_change;
643 	ret = clk_notifier_register(st->clkin, &st->nb);
644 	if (ret < 0)
645 		return ret;
646 
647 	return devm_add_action_or_reset(&spi->dev, admv8818_clk_notifier_unreg, st);
648 }
649 
admv8818_probe(struct spi_device * spi)650 static int admv8818_probe(struct spi_device *spi)
651 {
652 	struct iio_dev *indio_dev;
653 	struct regmap *regmap;
654 	struct admv8818_state *st;
655 	int ret;
656 
657 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
658 	if (!indio_dev)
659 		return -ENOMEM;
660 
661 	regmap = devm_regmap_init_spi(spi, &admv8818_regmap_config);
662 	if (IS_ERR(regmap))
663 		return PTR_ERR(regmap);
664 
665 	st = iio_priv(indio_dev);
666 	st->regmap = regmap;
667 
668 	indio_dev->info = &admv8818_info;
669 	indio_dev->name = "admv8818";
670 	indio_dev->channels = admv8818_channels;
671 	indio_dev->num_channels = ARRAY_SIZE(admv8818_channels);
672 
673 	st->spi = spi;
674 
675 	ret = admv8818_clk_setup(st);
676 	if (ret)
677 		return ret;
678 
679 	mutex_init(&st->lock);
680 
681 	ret = admv8818_init(st);
682 	if (ret)
683 		return ret;
684 
685 	return devm_iio_device_register(&spi->dev, indio_dev);
686 }
687 
688 static const struct spi_device_id admv8818_id[] = {
689 	{ "admv8818", 0 },
690 	{}
691 };
692 MODULE_DEVICE_TABLE(spi, admv8818_id);
693 
694 static const struct of_device_id admv8818_of_match[] = {
695 	{ .compatible = "adi,admv8818" },
696 	{}
697 };
698 MODULE_DEVICE_TABLE(of, admv8818_of_match);
699 
700 static struct spi_driver admv8818_driver = {
701 	.driver = {
702 		.name = "admv8818",
703 		.of_match_table = admv8818_of_match,
704 	},
705 	.probe = admv8818_probe,
706 	.id_table = admv8818_id,
707 };
708 module_spi_driver(admv8818_driver);
709 
710 MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com");
711 MODULE_DESCRIPTION("Analog Devices ADMV8818");
712 MODULE_LICENSE("GPL v2");
713