xref: /linux/drivers/iio/frequency/adrf6780.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ADRF6780 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/clkdev.h>
12 #include <linux/delay.h>
13 #include <linux/device.h>
14 #include <linux/iio/iio.h>
15 #include <linux/module.h>
16 #include <linux/spi/spi.h>
17 
18 #include <linux/unaligned.h>
19 
20 /* ADRF6780 Register Map */
21 #define ADRF6780_REG_CONTROL			0x00
22 #define ADRF6780_REG_ALARM_READBACK		0x01
23 #define ADRF6780_REG_ALARM_MASKS		0x02
24 #define ADRF6780_REG_ENABLE			0x03
25 #define ADRF6780_REG_LINEARIZE			0x04
26 #define ADRF6780_REG_LO_PATH			0x05
27 #define ADRF6780_REG_ADC_CONTROL		0x06
28 #define ADRF6780_REG_ADC_OUTPUT			0x0C
29 
30 /* ADRF6780_REG_CONTROL Map */
31 #define ADRF6780_PARITY_EN_MSK			BIT(15)
32 #define ADRF6780_SOFT_RESET_MSK			BIT(14)
33 #define ADRF6780_CHIP_ID_MSK			GENMASK(11, 4)
34 #define ADRF6780_CHIP_ID			0xA
35 #define ADRF6780_CHIP_REVISION_MSK		GENMASK(3, 0)
36 
37 /* ADRF6780_REG_ALARM_READBACK Map */
38 #define ADRF6780_PARITY_ERROR_MSK		BIT(15)
39 #define ADRF6780_TOO_FEW_ERRORS_MSK		BIT(14)
40 #define ADRF6780_TOO_MANY_ERRORS_MSK		BIT(13)
41 #define ADRF6780_ADDRESS_RANGE_ERROR_MSK	BIT(12)
42 
43 /* ADRF6780_REG_ENABLE Map */
44 #define ADRF6780_VGA_BUFFER_EN_MSK		BIT(8)
45 #define ADRF6780_DETECTOR_EN_MSK		BIT(7)
46 #define ADRF6780_LO_BUFFER_EN_MSK		BIT(6)
47 #define ADRF6780_IF_MODE_EN_MSK			BIT(5)
48 #define ADRF6780_IQ_MODE_EN_MSK			BIT(4)
49 #define ADRF6780_LO_X2_EN_MSK			BIT(3)
50 #define ADRF6780_LO_PPF_EN_MSK			BIT(2)
51 #define ADRF6780_LO_EN_MSK			BIT(1)
52 #define ADRF6780_UC_BIAS_EN_MSK			BIT(0)
53 
54 /* ADRF6780_REG_LINEARIZE Map */
55 #define ADRF6780_RDAC_LINEARIZE_MSK		GENMASK(7, 0)
56 
57 /* ADRF6780_REG_LO_PATH Map */
58 #define ADRF6780_LO_SIDEBAND_MSK		BIT(10)
59 #define ADRF6780_Q_PATH_PHASE_ACCURACY_MSK	GENMASK(7, 4)
60 #define ADRF6780_I_PATH_PHASE_ACCURACY_MSK	GENMASK(3, 0)
61 
62 /* ADRF6780_REG_ADC_CONTROL Map */
63 #define ADRF6780_VDET_OUTPUT_SELECT_MSK		BIT(3)
64 #define ADRF6780_ADC_START_MSK			BIT(2)
65 #define ADRF6780_ADC_EN_MSK			BIT(1)
66 #define ADRF6780_ADC_CLOCK_EN_MSK		BIT(0)
67 
68 /* ADRF6780_REG_ADC_OUTPUT Map */
69 #define ADRF6780_ADC_STATUS_MSK			BIT(8)
70 #define ADRF6780_ADC_VALUE_MSK			GENMASK(7, 0)
71 
72 struct adrf6780_state {
73 	struct spi_device	*spi;
74 	struct clk		*clkin;
75 	/* Protect against concurrent accesses to the device */
76 	struct mutex		lock;
77 	bool			vga_buff_en;
78 	bool			lo_buff_en;
79 	bool			if_mode_en;
80 	bool			iq_mode_en;
81 	bool			lo_x2_en;
82 	bool			lo_ppf_en;
83 	bool			lo_en;
84 	bool			uc_bias_en;
85 	bool			lo_sideband;
86 	bool			vdet_out_en;
87 	u8			data[3] __aligned(IIO_DMA_MINALIGN);
88 };
89 
90 static int __adrf6780_spi_read(struct adrf6780_state *st, unsigned int reg,
91 			       unsigned int *val)
92 {
93 	int ret;
94 	struct spi_transfer t = {0};
95 
96 	st->data[0] = 0x80 | (reg << 1);
97 	st->data[1] = 0x0;
98 	st->data[2] = 0x0;
99 
100 	t.rx_buf = &st->data[0];
101 	t.tx_buf = &st->data[0];
102 	t.len = 3;
103 
104 	ret = spi_sync_transfer(st->spi, &t, 1);
105 	if (ret)
106 		return ret;
107 
108 	*val = (get_unaligned_be24(&st->data[0]) >> 1) & GENMASK(15, 0);
109 
110 	return ret;
111 }
112 
113 static int adrf6780_spi_read(struct adrf6780_state *st, unsigned int reg,
114 			     unsigned int *val)
115 {
116 	int ret;
117 
118 	mutex_lock(&st->lock);
119 	ret = __adrf6780_spi_read(st, reg, val);
120 	mutex_unlock(&st->lock);
121 
122 	return ret;
123 }
124 
125 static int __adrf6780_spi_write(struct adrf6780_state *st,
126 				unsigned int reg,
127 				unsigned int val)
128 {
129 	put_unaligned_be24((val << 1) | (reg << 17), &st->data[0]);
130 
131 	return spi_write(st->spi, &st->data[0], 3);
132 }
133 
134 static int adrf6780_spi_write(struct adrf6780_state *st, unsigned int reg,
135 			      unsigned int val)
136 {
137 	int ret;
138 
139 	mutex_lock(&st->lock);
140 	ret = __adrf6780_spi_write(st, reg, val);
141 	mutex_unlock(&st->lock);
142 
143 	return ret;
144 }
145 
146 static int __adrf6780_spi_update_bits(struct adrf6780_state *st,
147 				      unsigned int reg, unsigned int mask,
148 				      unsigned int val)
149 {
150 	int ret;
151 	unsigned int data, temp;
152 
153 	ret = __adrf6780_spi_read(st, reg, &data);
154 	if (ret)
155 		return ret;
156 
157 	temp = (data & ~mask) | (val & mask);
158 
159 	return __adrf6780_spi_write(st, reg, temp);
160 }
161 
162 static int adrf6780_spi_update_bits(struct adrf6780_state *st, unsigned int reg,
163 				    unsigned int mask, unsigned int val)
164 {
165 	int ret;
166 
167 	mutex_lock(&st->lock);
168 	ret = __adrf6780_spi_update_bits(st, reg, mask, val);
169 	mutex_unlock(&st->lock);
170 
171 	return ret;
172 }
173 
174 static int adrf6780_read_adc_raw(struct adrf6780_state *st, unsigned int *read_val)
175 {
176 	int ret;
177 
178 	mutex_lock(&st->lock);
179 
180 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_ADC_CONTROL,
181 					 ADRF6780_ADC_EN_MSK |
182 					 ADRF6780_ADC_CLOCK_EN_MSK |
183 					 ADRF6780_ADC_START_MSK,
184 					 FIELD_PREP(ADRF6780_ADC_EN_MSK, 1) |
185 					 FIELD_PREP(ADRF6780_ADC_CLOCK_EN_MSK, 1) |
186 					 FIELD_PREP(ADRF6780_ADC_START_MSK, 1));
187 	if (ret)
188 		goto exit;
189 
190 	/*
191 	 * Per ADRF6780 datasheet (Rev. D, page 23, ADC section),
192 	 * wait approximately 200 us for the ADC to be ready.
193 	 */
194 	fsleep(200);
195 
196 	ret = __adrf6780_spi_read(st, ADRF6780_REG_ADC_OUTPUT, read_val);
197 	if (ret)
198 		goto exit;
199 
200 	if (!(*read_val & ADRF6780_ADC_STATUS_MSK)) {
201 		ret = -EINVAL;
202 		goto exit;
203 	}
204 
205 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_ADC_CONTROL,
206 					 ADRF6780_ADC_START_MSK,
207 					 FIELD_PREP(ADRF6780_ADC_START_MSK, 0));
208 	if (ret)
209 		goto exit;
210 
211 	ret = __adrf6780_spi_read(st, ADRF6780_REG_ADC_OUTPUT, read_val);
212 
213 exit:
214 	mutex_unlock(&st->lock);
215 	return ret;
216 }
217 
218 static int adrf6780_read_raw(struct iio_dev *indio_dev,
219 			     struct iio_chan_spec const *chan,
220 			     int *val, int *val2, long info)
221 {
222 	struct adrf6780_state *dev = iio_priv(indio_dev);
223 	unsigned int data;
224 	int ret;
225 
226 	switch (info) {
227 	case IIO_CHAN_INFO_RAW:
228 		ret = adrf6780_read_adc_raw(dev, &data);
229 		if (ret)
230 			return ret;
231 
232 		*val = data & ADRF6780_ADC_VALUE_MSK;
233 
234 		return IIO_VAL_INT;
235 
236 	case IIO_CHAN_INFO_SCALE:
237 		ret = adrf6780_spi_read(dev, ADRF6780_REG_LINEARIZE, &data);
238 		if (ret)
239 			return ret;
240 
241 		*val = data & ADRF6780_RDAC_LINEARIZE_MSK;
242 
243 		return IIO_VAL_INT;
244 	case IIO_CHAN_INFO_PHASE:
245 		ret = adrf6780_spi_read(dev, ADRF6780_REG_LO_PATH, &data);
246 		if (ret)
247 			return ret;
248 
249 		switch (chan->channel2) {
250 		case IIO_MOD_I:
251 			*val = data & ADRF6780_I_PATH_PHASE_ACCURACY_MSK;
252 
253 			return IIO_VAL_INT;
254 		case IIO_MOD_Q:
255 			*val = FIELD_GET(ADRF6780_Q_PATH_PHASE_ACCURACY_MSK,
256 					 data);
257 
258 			return IIO_VAL_INT;
259 		default:
260 			return -EINVAL;
261 		}
262 	default:
263 		return -EINVAL;
264 	}
265 }
266 
267 static int adrf6780_write_raw(struct iio_dev *indio_dev,
268 			      struct iio_chan_spec const *chan,
269 			      int val, int val2, long info)
270 {
271 	struct adrf6780_state *st = iio_priv(indio_dev);
272 
273 	switch (info) {
274 	case IIO_CHAN_INFO_SCALE:
275 		return adrf6780_spi_write(st, ADRF6780_REG_LINEARIZE, val);
276 	case IIO_CHAN_INFO_PHASE:
277 		switch (chan->channel2) {
278 		case IIO_MOD_I:
279 			return adrf6780_spi_update_bits(st,
280 				ADRF6780_REG_LO_PATH,
281 				ADRF6780_I_PATH_PHASE_ACCURACY_MSK,
282 				FIELD_PREP(ADRF6780_I_PATH_PHASE_ACCURACY_MSK, val));
283 		case IIO_MOD_Q:
284 			return adrf6780_spi_update_bits(st,
285 				ADRF6780_REG_LO_PATH,
286 				ADRF6780_Q_PATH_PHASE_ACCURACY_MSK,
287 				FIELD_PREP(ADRF6780_Q_PATH_PHASE_ACCURACY_MSK, val));
288 		default:
289 			return -EINVAL;
290 		}
291 	default:
292 		return -EINVAL;
293 	}
294 }
295 
296 static int adrf6780_reg_access(struct iio_dev *indio_dev,
297 			       unsigned int reg,
298 			       unsigned int write_val,
299 			       unsigned int *read_val)
300 {
301 	struct adrf6780_state *st = iio_priv(indio_dev);
302 
303 	if (read_val)
304 		return adrf6780_spi_read(st, reg, read_val);
305 	else
306 		return adrf6780_spi_write(st, reg, write_val);
307 }
308 
309 static const struct iio_info adrf6780_info = {
310 	.read_raw = adrf6780_read_raw,
311 	.write_raw = adrf6780_write_raw,
312 	.debugfs_reg_access = &adrf6780_reg_access,
313 };
314 
315 #define ADRF6780_CHAN_ADC(_channel) {			\
316 	.type = IIO_ALTVOLTAGE,				\
317 	.output = 0,					\
318 	.indexed = 1,					\
319 	.channel = _channel,				\
320 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)	\
321 }
322 
323 #define ADRF6780_CHAN_RDAC(_channel) {			\
324 	.type = IIO_ALTVOLTAGE,				\
325 	.output = 1,					\
326 	.indexed = 1,					\
327 	.channel = _channel,				\
328 	.info_mask_separate = BIT(IIO_CHAN_INFO_SCALE)	\
329 }
330 
331 #define ADRF6780_CHAN_IQ_PHASE(_channel, rf_comp) {		\
332 	.type = IIO_ALTVOLTAGE,					\
333 	.modified = 1,						\
334 	.output = 1,						\
335 	.indexed = 1,						\
336 	.channel2 = IIO_MOD_##rf_comp,				\
337 	.channel = _channel,					\
338 	.info_mask_separate = BIT(IIO_CHAN_INFO_PHASE)		\
339 }
340 
341 static const struct iio_chan_spec adrf6780_channels[] = {
342 	ADRF6780_CHAN_ADC(0),
343 	ADRF6780_CHAN_RDAC(0),
344 	ADRF6780_CHAN_IQ_PHASE(0, I),
345 	ADRF6780_CHAN_IQ_PHASE(0, Q),
346 };
347 
348 static int adrf6780_reset(struct adrf6780_state *st)
349 {
350 	int ret;
351 	struct device *dev = &st->spi->dev;
352 
353 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_CONTROL,
354 					 ADRF6780_SOFT_RESET_MSK,
355 					 FIELD_PREP(ADRF6780_SOFT_RESET_MSK, 1));
356 	if (ret)
357 		return dev_err_probe(dev, ret,
358 				     "ADRF6780 SPI software reset failed.\n");
359 
360 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_CONTROL,
361 					 ADRF6780_SOFT_RESET_MSK,
362 					 FIELD_PREP(ADRF6780_SOFT_RESET_MSK, 0));
363 	if (ret)
364 		return dev_err_probe(dev, ret,
365 				     "ADRF6780 SPI software reset disable failed.\n");
366 
367 	return 0;
368 }
369 
370 static int adrf6780_init(struct adrf6780_state *st)
371 {
372 	int ret;
373 	unsigned int chip_id, enable_reg, enable_reg_msk;
374 	struct device *dev = &st->spi->dev;
375 
376 	/* Perform a software reset */
377 	ret = adrf6780_reset(st);
378 	if (ret)
379 		return ret;
380 
381 	ret = __adrf6780_spi_read(st, ADRF6780_REG_CONTROL, &chip_id);
382 	if (ret)
383 		return ret;
384 
385 	chip_id = FIELD_GET(ADRF6780_CHIP_ID_MSK, chip_id);
386 	if (chip_id != ADRF6780_CHIP_ID)
387 		return dev_err_probe(dev, -EINVAL,
388 				     "ADRF6780 Invalid Chip ID.\n");
389 
390 	enable_reg_msk = ADRF6780_VGA_BUFFER_EN_MSK |
391 			ADRF6780_DETECTOR_EN_MSK |
392 			ADRF6780_LO_BUFFER_EN_MSK |
393 			ADRF6780_IF_MODE_EN_MSK |
394 			ADRF6780_IQ_MODE_EN_MSK |
395 			ADRF6780_LO_X2_EN_MSK |
396 			ADRF6780_LO_PPF_EN_MSK |
397 			ADRF6780_LO_EN_MSK |
398 			ADRF6780_UC_BIAS_EN_MSK;
399 
400 	enable_reg = FIELD_PREP(ADRF6780_VGA_BUFFER_EN_MSK, st->vga_buff_en) |
401 			FIELD_PREP(ADRF6780_DETECTOR_EN_MSK, 1) |
402 			FIELD_PREP(ADRF6780_LO_BUFFER_EN_MSK, st->lo_buff_en) |
403 			FIELD_PREP(ADRF6780_IF_MODE_EN_MSK, st->if_mode_en) |
404 			FIELD_PREP(ADRF6780_IQ_MODE_EN_MSK, st->iq_mode_en) |
405 			FIELD_PREP(ADRF6780_LO_X2_EN_MSK, st->lo_x2_en) |
406 			FIELD_PREP(ADRF6780_LO_PPF_EN_MSK, st->lo_ppf_en) |
407 			FIELD_PREP(ADRF6780_LO_EN_MSK, st->lo_en) |
408 			FIELD_PREP(ADRF6780_UC_BIAS_EN_MSK, st->uc_bias_en);
409 
410 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_ENABLE,
411 					 enable_reg_msk, enable_reg);
412 	if (ret)
413 		return ret;
414 
415 	ret = __adrf6780_spi_update_bits(st, ADRF6780_REG_LO_PATH,
416 					 ADRF6780_LO_SIDEBAND_MSK,
417 					 FIELD_PREP(ADRF6780_LO_SIDEBAND_MSK, st->lo_sideband));
418 	if (ret)
419 		return ret;
420 
421 	return __adrf6780_spi_update_bits(st, ADRF6780_REG_ADC_CONTROL,
422 		ADRF6780_VDET_OUTPUT_SELECT_MSK,
423 		FIELD_PREP(ADRF6780_VDET_OUTPUT_SELECT_MSK, st->vdet_out_en));
424 }
425 
426 static void adrf6780_properties_parse(struct adrf6780_state *st)
427 {
428 	struct device *dev = &st->spi->dev;
429 
430 	st->vga_buff_en = device_property_read_bool(dev, "adi,vga-buff-en");
431 	st->lo_buff_en = device_property_read_bool(dev, "adi,lo-buff-en");
432 	st->if_mode_en = device_property_read_bool(dev, "adi,if-mode-en");
433 	st->iq_mode_en = device_property_read_bool(dev, "adi,iq-mode-en");
434 	st->lo_x2_en = device_property_read_bool(dev, "adi,lo-x2-en");
435 	st->lo_ppf_en = device_property_read_bool(dev, "adi,lo-ppf-en");
436 	st->lo_en = device_property_read_bool(dev, "adi,lo-en");
437 	st->uc_bias_en = device_property_read_bool(dev, "adi,uc-bias-en");
438 	st->lo_sideband = device_property_read_bool(dev, "adi,lo-sideband");
439 	st->vdet_out_en = device_property_read_bool(dev, "adi,vdet-out-en");
440 }
441 
442 static void adrf6780_powerdown(void *data)
443 {
444 	/* Disable all components in the Enable Register */
445 	adrf6780_spi_write(data, ADRF6780_REG_ENABLE, 0x0);
446 }
447 
448 static int adrf6780_probe(struct spi_device *spi)
449 {
450 	struct iio_dev *indio_dev;
451 	struct adrf6780_state *st;
452 	struct device *dev = &spi->dev;
453 	int ret;
454 
455 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
456 	if (!indio_dev)
457 		return -ENOMEM;
458 
459 	st = iio_priv(indio_dev);
460 
461 	indio_dev->info = &adrf6780_info;
462 	indio_dev->name = "adrf6780";
463 	indio_dev->channels = adrf6780_channels;
464 	indio_dev->num_channels = ARRAY_SIZE(adrf6780_channels);
465 
466 	st->spi = spi;
467 
468 	adrf6780_properties_parse(st);
469 
470 	st->clkin = devm_clk_get_enabled(dev, "lo_in");
471 	if (IS_ERR(st->clkin))
472 		return dev_err_probe(dev, PTR_ERR(st->clkin),
473 				     "failed to get the LO input clock\n");
474 
475 	mutex_init(&st->lock);
476 
477 	ret = adrf6780_init(st);
478 	if (ret)
479 		return ret;
480 
481 	ret = devm_add_action_or_reset(dev, adrf6780_powerdown, st);
482 	if (ret)
483 		return ret;
484 
485 	return devm_iio_device_register(dev, indio_dev);
486 }
487 
488 static const struct spi_device_id adrf6780_id[] = {
489 	{ .name = "adrf6780" },
490 	{ }
491 };
492 MODULE_DEVICE_TABLE(spi, adrf6780_id);
493 
494 static const struct of_device_id adrf6780_of_match[] = {
495 	{ .compatible = "adi,adrf6780" },
496 	{ }
497 };
498 MODULE_DEVICE_TABLE(of, adrf6780_of_match);
499 
500 static struct spi_driver adrf6780_driver = {
501 	.driver = {
502 		.name = "adrf6780",
503 		.of_match_table = adrf6780_of_match,
504 	},
505 	.probe = adrf6780_probe,
506 	.id_table = adrf6780_id,
507 };
508 module_spi_driver(adrf6780_driver);
509 
510 MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com");
511 MODULE_DESCRIPTION("Analog Devices ADRF6780");
512 MODULE_LICENSE("GPL v2");
513