xref: /linux/drivers/iio/adc/ad7606.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AD7606 SPI ADC driver
4  *
5  * Copyright 2011 Analog Devices Inc.
6  */
7 
8 #include <linux/cleanup.h>
9 #include <linux/delay.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/property.h>
18 #include <linux/pwm.h>
19 #include <linux/regulator/consumer.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/sysfs.h>
23 #include <linux/units.h>
24 #include <linux/util_macros.h>
25 
26 #include <linux/iio/backend.h>
27 #include <linux/iio/buffer.h>
28 #include <linux/iio/iio.h>
29 #include <linux/iio/sysfs.h>
30 #include <linux/iio/trigger.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include <linux/iio/trigger_consumer.h>
33 
34 #include "ad7606.h"
35 
36 #define AD7606_CALIB_GAIN_MIN	0
37 #define AD7606_CALIB_GAIN_STEP	1024
38 #define AD7606_CALIB_GAIN_MAX	(63 * AD7606_CALIB_GAIN_STEP)
39 
40 /*
41  * Scales are computed as 5000/32768 and 10000/32768 respectively,
42  * so that when applied to the raw values they provide mV values.
43  * The scale arrays are kept as IIO_VAL_INT_PLUS_MICRO, so index
44  * X is the integer part and X + 1 is the fractional part.
45  */
46 static const unsigned int ad7606_16bit_hw_scale_avail[2][2] = {
47 	{ 0, 152588 }, { 0, 305176 }
48 };
49 
50 static const unsigned int ad7606_18bit_hw_scale_avail[2][2] = {
51 	{ 0, 38147 }, { 0, 76294 }
52 };
53 
54 static const unsigned int ad7606c_16bit_single_ended_unipolar_scale_avail[3][2] = {
55 	{ 0, 76294 }, { 0, 152588 }, { 0, 190735 }
56 };
57 
58 static const unsigned int ad7606c_16bit_single_ended_bipolar_scale_avail[5][2] = {
59 	{ 0, 76294 }, { 0, 152588 }, { 0, 190735 }, { 0, 305176 }, { 0, 381470 }
60 };
61 
62 static const unsigned int ad7606c_16bit_differential_bipolar_scale_avail[4][2] = {
63 	{ 0, 152588 }, { 0, 305176 }, { 0, 381470 }, { 0, 610352 }
64 };
65 
66 static const unsigned int ad7606c_18bit_single_ended_unipolar_scale_avail[3][2] = {
67 	{ 0, 19073 }, { 0, 38147 }, { 0, 47684 }
68 };
69 
70 static const unsigned int ad7606c_18bit_single_ended_bipolar_scale_avail[5][2] = {
71 	{ 0, 19073 }, { 0, 38147 }, { 0, 47684 }, { 0, 76294 }, { 0, 95367 }
72 };
73 
74 static const unsigned int ad7606c_18bit_differential_bipolar_scale_avail[4][2] = {
75 	{ 0, 38147 }, { 0, 76294 }, { 0, 95367 }, { 0, 152588 }
76 };
77 
78 static const unsigned int ad7606_16bit_sw_scale_avail[3][2] = {
79 	{ 0, 76293 }, { 0, 152588 }, { 0, 305176 }
80 };
81 
82 static const unsigned int ad7607_hw_scale_avail[2][2] = {
83 	{ 0, 610352 }, { 1, 220703 }
84 };
85 
86 static const unsigned int ad7609_hw_scale_avail[2][2] = {
87 	{ 0, 152588 }, { 0, 305176 }
88 };
89 
90 static const unsigned int ad7606_oversampling_avail[7] = {
91 	1, 2, 4, 8, 16, 32, 64,
92 };
93 
94 static const unsigned int ad7606b_oversampling_avail[9] = {
95 	1, 2, 4, 8, 16, 32, 64, 128, 256,
96 };
97 
98 static const unsigned int ad7616_oversampling_avail[8] = {
99 	1, 2, 4, 8, 16, 32, 64, 128,
100 };
101 
102 static const int ad7606_calib_offset_avail[3] = {
103 	-128, 1, 127,
104 };
105 
106 static const int ad7606c_18bit_calib_offset_avail[3] = {
107 	-512, 4, 508,
108 };
109 
110 static const int ad7606b_calib_phase_avail[][2] = {
111 	{ 0, 0 }, { 0, 1250 }, { 0, 318750 },
112 };
113 
114 static const int ad7606c_calib_phase_avail[][2] = {
115 	{ 0, 0 }, { 0, 1000 }, { 0, 255000 },
116 };
117 
118 static int ad7606c_18bit_chan_scale_setup(struct iio_dev *indio_dev,
119 					  struct iio_chan_spec *chan);
120 static int ad7606c_16bit_chan_scale_setup(struct iio_dev *indio_dev,
121 					  struct iio_chan_spec *chan);
122 static int ad7606_16bit_chan_scale_setup(struct iio_dev *indio_dev,
123 					 struct iio_chan_spec *chan);
124 static int ad7607_chan_scale_setup(struct iio_dev *indio_dev,
125 				   struct iio_chan_spec *chan);
126 static int ad7608_chan_scale_setup(struct iio_dev *indio_dev,
127 				   struct iio_chan_spec *chan);
128 static int ad7609_chan_scale_setup(struct iio_dev *indio_dev,
129 				   struct iio_chan_spec *chan);
130 static int ad7616_sw_mode_setup(struct iio_dev *indio_dev);
131 static int ad7606b_sw_mode_setup(struct iio_dev *indio_dev);
132 
133 const struct ad7606_chip_info ad7605_4_info = {
134 	.max_samplerate = 300 * KILO,
135 	.name = "ad7605-4",
136 	.bits = 16,
137 	.num_adc_channels = 4,
138 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
139 };
140 EXPORT_SYMBOL_NS_GPL(ad7605_4_info, "IIO_AD7606");
141 
142 const struct ad7606_chip_info ad7606_8_info = {
143 	.max_samplerate = 200 * KILO,
144 	.name = "ad7606-8",
145 	.bits = 16,
146 	.num_adc_channels = 8,
147 	.oversampling_avail = ad7606_oversampling_avail,
148 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
149 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
150 };
151 EXPORT_SYMBOL_NS_GPL(ad7606_8_info, "IIO_AD7606");
152 
153 const struct ad7606_chip_info ad7606_6_info = {
154 	.max_samplerate = 200 * KILO,
155 	.name = "ad7606-6",
156 	.bits = 16,
157 	.num_adc_channels = 6,
158 	.oversampling_avail = ad7606_oversampling_avail,
159 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
160 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
161 	.offload_storagebits = 32,
162 };
163 EXPORT_SYMBOL_NS_GPL(ad7606_6_info, "IIO_AD7606");
164 
165 const struct ad7606_chip_info ad7606_4_info = {
166 	.max_samplerate = 200 * KILO,
167 	.name = "ad7606-4",
168 	.bits = 16,
169 	.num_adc_channels = 4,
170 	.oversampling_avail = ad7606_oversampling_avail,
171 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
172 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
173 	.offload_storagebits = 32,
174 };
175 EXPORT_SYMBOL_NS_GPL(ad7606_4_info, "IIO_AD7606");
176 
177 const struct ad7606_chip_info ad7606b_info = {
178 	.max_samplerate = 800 * KILO,
179 	.name = "ad7606b",
180 	.bits = 16,
181 	.num_adc_channels = 8,
182 	.oversampling_avail = ad7606_oversampling_avail,
183 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
184 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
185 	.sw_setup_cb = ad7606b_sw_mode_setup,
186 	.offload_storagebits = 32,
187 	.calib_gain_avail = true,
188 	.calib_offset_avail = ad7606_calib_offset_avail,
189 	.calib_phase_avail = ad7606b_calib_phase_avail,
190 };
191 EXPORT_SYMBOL_NS_GPL(ad7606b_info, "IIO_AD7606");
192 
193 const struct ad7606_chip_info ad7606c_16_info = {
194 	.max_samplerate = 1 * MEGA,
195 	.name = "ad7606c16",
196 	.bits = 16,
197 	.num_adc_channels = 8,
198 	.oversampling_avail = ad7606_oversampling_avail,
199 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
200 	.scale_setup_cb = ad7606c_16bit_chan_scale_setup,
201 	.sw_setup_cb = ad7606b_sw_mode_setup,
202 	.offload_storagebits = 32,
203 	.calib_gain_avail = true,
204 	.calib_offset_avail = ad7606_calib_offset_avail,
205 	.calib_phase_avail = ad7606c_calib_phase_avail,
206 };
207 EXPORT_SYMBOL_NS_GPL(ad7606c_16_info, "IIO_AD7606");
208 
209 const struct ad7606_chip_info ad7607_info = {
210 	.max_samplerate = 200 * KILO,
211 	.name = "ad7607",
212 	.bits = 14,
213 	.num_adc_channels = 8,
214 	.oversampling_avail = ad7606_oversampling_avail,
215 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
216 	.scale_setup_cb = ad7607_chan_scale_setup,
217 	.offload_storagebits = 32,
218 };
219 EXPORT_SYMBOL_NS_GPL(ad7607_info, "IIO_AD7606");
220 
221 const struct ad7606_chip_info ad7608_info = {
222 	.max_samplerate = 200 * KILO,
223 	.name = "ad7608",
224 	.bits = 18,
225 	.num_adc_channels = 8,
226 	.oversampling_avail = ad7606_oversampling_avail,
227 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
228 	.scale_setup_cb = ad7608_chan_scale_setup,
229 	.offload_storagebits = 32,
230 };
231 EXPORT_SYMBOL_NS_GPL(ad7608_info, "IIO_AD7606");
232 
233 const struct ad7606_chip_info ad7609_info = {
234 	.max_samplerate = 200 * KILO,
235 	.name = "ad7609",
236 	.bits = 18,
237 	.num_adc_channels = 8,
238 	.oversampling_avail = ad7606_oversampling_avail,
239 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
240 	.scale_setup_cb = ad7609_chan_scale_setup,
241 	.offload_storagebits = 32,
242 };
243 EXPORT_SYMBOL_NS_GPL(ad7609_info, "IIO_AD7606");
244 
245 const struct ad7606_chip_info ad7606c_18_info = {
246 	.max_samplerate = 1 * MEGA,
247 	.name = "ad7606c18",
248 	.bits = 18,
249 	.num_adc_channels = 8,
250 	.oversampling_avail = ad7606_oversampling_avail,
251 	.oversampling_num = ARRAY_SIZE(ad7606_oversampling_avail),
252 	.scale_setup_cb = ad7606c_18bit_chan_scale_setup,
253 	.sw_setup_cb = ad7606b_sw_mode_setup,
254 	.offload_storagebits = 32,
255 	.calib_gain_avail = true,
256 	.calib_offset_avail = ad7606c_18bit_calib_offset_avail,
257 	.calib_phase_avail = ad7606c_calib_phase_avail,
258 };
259 EXPORT_SYMBOL_NS_GPL(ad7606c_18_info, "IIO_AD7606");
260 
261 const struct ad7606_chip_info ad7616_info = {
262 	.max_samplerate = 1 * MEGA,
263 	.init_delay_ms = 15,
264 	.name = "ad7616",
265 	.bits = 16,
266 	.num_adc_channels = 16,
267 	.oversampling_avail = ad7616_oversampling_avail,
268 	.oversampling_num = ARRAY_SIZE(ad7616_oversampling_avail),
269 	.os_req_reset = true,
270 	.scale_setup_cb = ad7606_16bit_chan_scale_setup,
271 	.sw_setup_cb = ad7616_sw_mode_setup,
272 	.offload_storagebits = 16,
273 };
274 EXPORT_SYMBOL_NS_GPL(ad7616_info, "IIO_AD7606");
275 
ad7606_reset(struct ad7606_state * st)276 int ad7606_reset(struct ad7606_state *st)
277 {
278 	if (st->gpio_reset) {
279 		gpiod_set_value(st->gpio_reset, 1);
280 		ndelay(100); /* t_reset >= 100ns */
281 		gpiod_set_value(st->gpio_reset, 0);
282 		return 0;
283 	}
284 
285 	return -ENODEV;
286 }
287 EXPORT_SYMBOL_NS_GPL(ad7606_reset, "IIO_AD7606");
288 
ad7606_16bit_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)289 static int ad7606_16bit_chan_scale_setup(struct iio_dev *indio_dev,
290 					 struct iio_chan_spec *chan)
291 {
292 	struct ad7606_state *st = iio_priv(indio_dev);
293 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
294 
295 	if (!st->sw_mode_en) {
296 		/* tied to logic low, analog input range is +/- 5V */
297 		ci->range = 0;
298 		ci->scale_avail = ad7606_16bit_hw_scale_avail;
299 		ci->num_scales = ARRAY_SIZE(ad7606_16bit_hw_scale_avail);
300 		return 0;
301 	}
302 
303 	/* Scale of 0.076293 is only available in sw mode */
304 	/* After reset, in software mode, ±10 V is set by default */
305 	ci->range = 2;
306 	ci->scale_avail = ad7606_16bit_sw_scale_avail;
307 	ci->num_scales = ARRAY_SIZE(ad7606_16bit_sw_scale_avail);
308 
309 	return 0;
310 }
311 
ad7606_get_chan_config(struct iio_dev * indio_dev,int ch,bool * bipolar,bool * differential)312 static int ad7606_get_chan_config(struct iio_dev *indio_dev, int ch,
313 				  bool *bipolar, bool *differential)
314 {
315 	struct ad7606_state *st = iio_priv(indio_dev);
316 	struct ad7606_chan_info *ci;
317 	unsigned int num_channels = st->chip_info->num_adc_channels;
318 	struct device *dev = st->dev;
319 	int ret;
320 
321 	*bipolar = false;
322 	*differential = false;
323 
324 	device_for_each_child_node_scoped(dev, child) {
325 		u32 pins[2];
326 		int reg;
327 
328 		ret = fwnode_property_read_u32(child, "reg", &reg);
329 		if (ret)
330 			return ret;
331 
332 		/* channel number (here) is from 1 to num_channels */
333 		if (reg < 1 || reg > num_channels)
334 			return -EINVAL;
335 
336 		/* Loop until we are in the right channel. */
337 		if (reg != (ch + 1))
338 			continue;
339 
340 		*bipolar = fwnode_property_read_bool(child, "bipolar");
341 
342 		ret = fwnode_property_read_u32_array(child, "diff-channels",
343 						     pins, ARRAY_SIZE(pins));
344 		/* Channel is differential, if pins are the same as 'reg' */
345 		if (ret == 0 && (pins[0] != reg || pins[1] != reg)) {
346 			dev_err(dev,
347 				"Differential pins must be the same as 'reg'");
348 			return -EINVAL;
349 		}
350 
351 		*differential = (ret == 0);
352 
353 		if (*differential && !*bipolar) {
354 			dev_err(dev,
355 				"'bipolar' must be added for diff channel %d\n",
356 				reg);
357 			return -EINVAL;
358 		}
359 
360 		ci = &st->chan_info[reg - 1];
361 
362 		ci->r_gain = 0;
363 		ret = fwnode_property_read_u32(child, "adi,rfilter-ohms",
364 					       &ci->r_gain);
365 		if (ret == 0 && ci->r_gain > AD7606_CALIB_GAIN_MAX)
366 			return -EINVAL;
367 
368 		return 0;
369 	}
370 
371 	return 0;
372 }
373 
ad7606c_18bit_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)374 static int ad7606c_18bit_chan_scale_setup(struct iio_dev *indio_dev,
375 					  struct iio_chan_spec *chan)
376 {
377 	struct ad7606_state *st = iio_priv(indio_dev);
378 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
379 	bool bipolar, differential;
380 	int ret;
381 
382 	if (!st->sw_mode_en) {
383 		ci->range = 0;
384 		ci->scale_avail = ad7606_18bit_hw_scale_avail;
385 		ci->num_scales = ARRAY_SIZE(ad7606_18bit_hw_scale_avail);
386 		return 0;
387 	}
388 
389 	ret = ad7606_get_chan_config(indio_dev, chan->scan_index, &bipolar,
390 				     &differential);
391 	if (ret)
392 		return ret;
393 
394 	if (differential) {
395 		ci->scale_avail = ad7606c_18bit_differential_bipolar_scale_avail;
396 		ci->num_scales =
397 			ARRAY_SIZE(ad7606c_18bit_differential_bipolar_scale_avail);
398 		/* Bipolar differential ranges start at 8 (b1000) */
399 		ci->reg_offset = 8;
400 		ci->range = 1;
401 		chan->differential = 1;
402 		chan->channel2 = chan->channel;
403 
404 		return 0;
405 	}
406 
407 	chan->differential = 0;
408 
409 	if (bipolar) {
410 		ci->scale_avail = ad7606c_18bit_single_ended_bipolar_scale_avail;
411 		ci->num_scales =
412 			ARRAY_SIZE(ad7606c_18bit_single_ended_bipolar_scale_avail);
413 		/* Bipolar single-ended ranges start at 0 (b0000) */
414 		ci->reg_offset = 0;
415 		ci->range = 3;
416 		chan->scan_type.sign = 's';
417 
418 		return 0;
419 	}
420 
421 	ci->scale_avail = ad7606c_18bit_single_ended_unipolar_scale_avail;
422 	ci->num_scales =
423 		ARRAY_SIZE(ad7606c_18bit_single_ended_unipolar_scale_avail);
424 	/* Unipolar single-ended ranges start at 5 (b0101) */
425 	ci->reg_offset = 5;
426 	ci->range = 1;
427 	chan->scan_type.sign = 'u';
428 
429 	return 0;
430 }
431 
ad7606c_16bit_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)432 static int ad7606c_16bit_chan_scale_setup(struct iio_dev *indio_dev,
433 					  struct iio_chan_spec *chan)
434 {
435 	struct ad7606_state *st = iio_priv(indio_dev);
436 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
437 	bool bipolar, differential;
438 	int ret;
439 
440 	if (!st->sw_mode_en) {
441 		ci->range = 0;
442 		ci->scale_avail = ad7606_16bit_hw_scale_avail;
443 		ci->num_scales = ARRAY_SIZE(ad7606_16bit_hw_scale_avail);
444 		return 0;
445 	}
446 
447 	ret = ad7606_get_chan_config(indio_dev, chan->scan_index, &bipolar,
448 				     &differential);
449 	if (ret)
450 		return ret;
451 
452 	if (differential) {
453 		ci->scale_avail = ad7606c_16bit_differential_bipolar_scale_avail;
454 		ci->num_scales =
455 			ARRAY_SIZE(ad7606c_16bit_differential_bipolar_scale_avail);
456 		/* Bipolar differential ranges start at 8 (b1000) */
457 		ci->reg_offset = 8;
458 		ci->range = 1;
459 		chan->differential = 1;
460 		chan->channel2 = chan->channel;
461 		chan->scan_type.sign = 's';
462 
463 		return 0;
464 	}
465 
466 	chan->differential = 0;
467 
468 	if (bipolar) {
469 		ci->scale_avail = ad7606c_16bit_single_ended_bipolar_scale_avail;
470 		ci->num_scales =
471 			ARRAY_SIZE(ad7606c_16bit_single_ended_bipolar_scale_avail);
472 		/* Bipolar single-ended ranges start at 0 (b0000) */
473 		ci->reg_offset = 0;
474 		ci->range = 3;
475 		chan->scan_type.sign = 's';
476 
477 		return 0;
478 	}
479 
480 	ci->scale_avail = ad7606c_16bit_single_ended_unipolar_scale_avail;
481 	ci->num_scales =
482 		ARRAY_SIZE(ad7606c_16bit_single_ended_unipolar_scale_avail);
483 	/* Unipolar single-ended ranges start at 5 (b0101) */
484 	ci->reg_offset = 5;
485 	ci->range = 1;
486 	chan->scan_type.sign = 'u';
487 
488 	return 0;
489 }
490 
ad7607_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)491 static int ad7607_chan_scale_setup(struct iio_dev *indio_dev,
492 				   struct iio_chan_spec *chan)
493 {
494 	struct ad7606_state *st = iio_priv(indio_dev);
495 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
496 
497 	ci->range = 0;
498 	ci->scale_avail = ad7607_hw_scale_avail;
499 	ci->num_scales = ARRAY_SIZE(ad7607_hw_scale_avail);
500 	return 0;
501 }
502 
ad7608_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)503 static int ad7608_chan_scale_setup(struct iio_dev *indio_dev,
504 				   struct iio_chan_spec *chan)
505 {
506 	struct ad7606_state *st = iio_priv(indio_dev);
507 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
508 
509 	ci->range = 0;
510 	ci->scale_avail = ad7606_18bit_hw_scale_avail;
511 	ci->num_scales = ARRAY_SIZE(ad7606_18bit_hw_scale_avail);
512 	return 0;
513 }
514 
ad7609_chan_scale_setup(struct iio_dev * indio_dev,struct iio_chan_spec * chan)515 static int ad7609_chan_scale_setup(struct iio_dev *indio_dev,
516 				   struct iio_chan_spec *chan)
517 {
518 	struct ad7606_state *st = iio_priv(indio_dev);
519 	struct ad7606_chan_info *ci = &st->chan_info[chan->scan_index];
520 
521 	ci->range = 0;
522 	ci->scale_avail = ad7609_hw_scale_avail;
523 	ci->num_scales = ARRAY_SIZE(ad7609_hw_scale_avail);
524 	return 0;
525 }
526 
ad7606_reg_access(struct iio_dev * indio_dev,unsigned int reg,unsigned int writeval,unsigned int * readval)527 static int ad7606_reg_access(struct iio_dev *indio_dev,
528 			     unsigned int reg,
529 			     unsigned int writeval,
530 			     unsigned int *readval)
531 {
532 	struct ad7606_state *st = iio_priv(indio_dev);
533 	int ret;
534 
535 	guard(mutex)(&st->lock);
536 
537 	if (readval) {
538 		ret = st->bops->reg_read(st, reg);
539 		if (ret < 0)
540 			return ret;
541 		*readval = ret;
542 		return 0;
543 	} else {
544 		return st->bops->reg_write(st, reg, writeval);
545 	}
546 }
547 
ad7606_pwm_set_high(struct ad7606_state * st)548 static int ad7606_pwm_set_high(struct ad7606_state *st)
549 {
550 	struct pwm_state cnvst_pwm_state;
551 	int ret;
552 
553 	pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
554 	cnvst_pwm_state.enabled = true;
555 	cnvst_pwm_state.duty_cycle = cnvst_pwm_state.period;
556 
557 	ret = pwm_apply_might_sleep(st->cnvst_pwm, &cnvst_pwm_state);
558 
559 	return ret;
560 }
561 
ad7606_pwm_set_low(struct ad7606_state * st)562 int ad7606_pwm_set_low(struct ad7606_state *st)
563 {
564 	struct pwm_state cnvst_pwm_state;
565 	int ret;
566 
567 	pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
568 	cnvst_pwm_state.enabled = true;
569 	cnvst_pwm_state.duty_cycle = 0;
570 
571 	ret = pwm_apply_might_sleep(st->cnvst_pwm, &cnvst_pwm_state);
572 
573 	return ret;
574 }
575 EXPORT_SYMBOL_NS_GPL(ad7606_pwm_set_low, "IIO_AD7606");
576 
ad7606_pwm_set_swing(struct ad7606_state * st)577 int ad7606_pwm_set_swing(struct ad7606_state *st)
578 {
579 	struct pwm_state cnvst_pwm_state;
580 
581 	pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
582 	cnvst_pwm_state.enabled = true;
583 	cnvst_pwm_state.duty_cycle = cnvst_pwm_state.period / 2;
584 
585 	return pwm_apply_might_sleep(st->cnvst_pwm, &cnvst_pwm_state);
586 }
587 EXPORT_SYMBOL_NS_GPL(ad7606_pwm_set_swing, "IIO_AD7606");
588 
ad7606_pwm_is_swinging(struct ad7606_state * st)589 static bool ad7606_pwm_is_swinging(struct ad7606_state *st)
590 {
591 	struct pwm_state cnvst_pwm_state;
592 
593 	pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
594 
595 	return cnvst_pwm_state.duty_cycle != cnvst_pwm_state.period &&
596 	       cnvst_pwm_state.duty_cycle != 0;
597 }
598 
ad7606_set_sampling_freq(struct ad7606_state * st,unsigned long freq)599 static int ad7606_set_sampling_freq(struct ad7606_state *st, unsigned long freq)
600 {
601 	struct pwm_state cnvst_pwm_state;
602 	bool is_swinging = ad7606_pwm_is_swinging(st);
603 	bool is_high;
604 
605 	if (freq == 0)
606 		return -EINVAL;
607 
608 	/* Retrieve the previous state. */
609 	pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
610 	is_high = cnvst_pwm_state.duty_cycle == cnvst_pwm_state.period;
611 
612 	cnvst_pwm_state.period = DIV_ROUND_UP_ULL(NSEC_PER_SEC, freq);
613 	cnvst_pwm_state.polarity = PWM_POLARITY_NORMAL;
614 	if (is_high)
615 		cnvst_pwm_state.duty_cycle = cnvst_pwm_state.period;
616 	else if (is_swinging)
617 		cnvst_pwm_state.duty_cycle = cnvst_pwm_state.period / 2;
618 	else
619 		cnvst_pwm_state.duty_cycle = 0;
620 
621 	return pwm_apply_might_sleep(st->cnvst_pwm, &cnvst_pwm_state);
622 }
623 
ad7606_read_samples(struct ad7606_state * st)624 static int ad7606_read_samples(struct ad7606_state *st)
625 {
626 	unsigned int num = st->chip_info->num_adc_channels;
627 
628 	return st->bops->read_block(st->dev, num, &st->data);
629 }
630 
ad7606_trigger_handler(int irq,void * p)631 static irqreturn_t ad7606_trigger_handler(int irq, void *p)
632 {
633 	struct iio_poll_func *pf = p;
634 	struct iio_dev *indio_dev = pf->indio_dev;
635 	struct ad7606_state *st = iio_priv(indio_dev);
636 	int ret;
637 
638 	guard(mutex)(&st->lock);
639 
640 	ret = ad7606_read_samples(st);
641 	if (ret)
642 		goto error_ret;
643 
644 	iio_push_to_buffers_with_ts(indio_dev, &st->data, sizeof(st->data),
645 				    iio_get_time_ns(indio_dev));
646 error_ret:
647 	iio_trigger_notify_done(indio_dev->trig);
648 	/* The rising edge of the CONVST signal starts a new conversion. */
649 	gpiod_set_value(st->gpio_convst, 1);
650 
651 	return IRQ_HANDLED;
652 }
653 
ad7606_scan_direct(struct iio_dev * indio_dev,unsigned int ch,int * val)654 static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch,
655 			      int *val)
656 {
657 	struct ad7606_state *st = iio_priv(indio_dev);
658 	const struct iio_chan_spec *chan;
659 	unsigned int realbits;
660 	int ret;
661 
662 	if (st->gpio_convst) {
663 		gpiod_set_value(st->gpio_convst, 1);
664 	} else {
665 		ret = ad7606_pwm_set_high(st);
666 		if (ret < 0)
667 			return ret;
668 	}
669 
670 	/*
671 	 * If no backend, wait for the interruption on busy pin, otherwise just add
672 	 * a delay to leave time for the data to be available. For now, the latter
673 	 * will not happen because IIO_CHAN_INFO_RAW is not supported for the backend.
674 	 * TODO: Add support for reading a single value when the backend is used.
675 	 */
676 	if (st->trig) {
677 		ret = wait_for_completion_timeout(&st->completion,
678 						  msecs_to_jiffies(1000));
679 		if (!ret) {
680 			ret = -ETIMEDOUT;
681 			goto error_ret;
682 		}
683 	} else {
684 		/*
685 		 * If the BUSY interrupt is not available, wait enough time for
686 		 * the longest possible conversion (max for the whole family is
687 		 * around 350us).
688 		 */
689 		fsleep(400);
690 	}
691 
692 	ret = ad7606_read_samples(st);
693 	if (ret)
694 		goto error_ret;
695 
696 	chan = &indio_dev->channels[ch];
697 	realbits = chan->scan_type.realbits;
698 
699 	if (realbits > 16)
700 		*val = st->data.buf32[ch];
701 	else
702 		*val = st->data.buf16[ch];
703 
704 	*val &= GENMASK(realbits - 1, 0);
705 
706 	if (chan->scan_type.sign == 's')
707 		*val = sign_extend32(*val, realbits - 1);
708 
709 error_ret:
710 	if (!st->gpio_convst) {
711 		ret = ad7606_pwm_set_low(st);
712 		if (ret < 0)
713 			return ret;
714 	}
715 	gpiod_set_value(st->gpio_convst, 0);
716 
717 	return ret;
718 }
719 
ad7606_get_calib_offset(struct ad7606_state * st,int ch,int * val)720 static int ad7606_get_calib_offset(struct ad7606_state *st, int ch, int *val)
721 {
722 	int ret;
723 
724 	ret = st->bops->reg_read(st, AD7606_CALIB_OFFSET(ch));
725 	if (ret < 0)
726 		return ret;
727 
728 	*val = st->chip_info->calib_offset_avail[0] +
729 	       ret * st->chip_info->calib_offset_avail[1];
730 
731 	return 0;
732 }
733 
ad7606_get_calib_phase(struct ad7606_state * st,int ch,int * val,int * val2)734 static int ad7606_get_calib_phase(struct ad7606_state *st, int ch, int *val,
735 				  int *val2)
736 {
737 	int ret;
738 
739 	ret = st->bops->reg_read(st, AD7606_CALIB_PHASE(ch));
740 	if (ret < 0)
741 		return ret;
742 
743 	*val = 0;
744 
745 	/*
746 	 * ad7606b: phase delay from 0 to 318.75 μs in steps of 1.25 μs.
747 	 * ad7606c-16/18: phase delay from 0 µs to 255 µs in steps of 1 µs.
748 	 */
749 	*val2 = ret * st->chip_info->calib_phase_avail[1][1];
750 
751 	return 0;
752 }
753 
ad7606_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)754 static int ad7606_read_raw(struct iio_dev *indio_dev,
755 			   struct iio_chan_spec const *chan,
756 			   int *val,
757 			   int *val2,
758 			   long m)
759 {
760 	int ret, ch = 0;
761 	struct ad7606_state *st = iio_priv(indio_dev);
762 	struct ad7606_chan_info *ci;
763 	struct pwm_state cnvst_pwm_state;
764 
765 	switch (m) {
766 	case IIO_CHAN_INFO_RAW:
767 		if (!iio_device_claim_direct(indio_dev))
768 			return -EBUSY;
769 		ret = ad7606_scan_direct(indio_dev, chan->scan_index, val);
770 		iio_device_release_direct(indio_dev);
771 		if (ret < 0)
772 			return ret;
773 		return IIO_VAL_INT;
774 	case IIO_CHAN_INFO_SCALE:
775 		if (st->sw_mode_en)
776 			ch = chan->scan_index;
777 		ci = &st->chan_info[ch];
778 		*val = ci->scale_avail[ci->range][0];
779 		*val2 = ci->scale_avail[ci->range][1];
780 		return IIO_VAL_INT_PLUS_MICRO;
781 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
782 		*val = st->oversampling;
783 		return IIO_VAL_INT;
784 	case IIO_CHAN_INFO_SAMP_FREQ:
785 		pwm_get_state(st->cnvst_pwm, &cnvst_pwm_state);
786 		*val = DIV_ROUND_CLOSEST_ULL(NSEC_PER_SEC, cnvst_pwm_state.period);
787 		return IIO_VAL_INT;
788 	case IIO_CHAN_INFO_CALIBBIAS:
789 		if (!iio_device_claim_direct(indio_dev))
790 			return -EBUSY;
791 		ret = ad7606_get_calib_offset(st, chan->scan_index, val);
792 		iio_device_release_direct(indio_dev);
793 		if (ret)
794 			return ret;
795 		return IIO_VAL_INT;
796 	case IIO_CHAN_INFO_CONVDELAY:
797 		if (!iio_device_claim_direct(indio_dev))
798 			return -EBUSY;
799 		ret = ad7606_get_calib_phase(st, chan->scan_index, val, val2);
800 		iio_device_release_direct(indio_dev);
801 		if (ret)
802 			return ret;
803 		return IIO_VAL_INT_PLUS_NANO;
804 	}
805 	return -EINVAL;
806 }
807 
in_voltage_scale_available_show(struct device * dev,struct device_attribute * attr,char * buf)808 static ssize_t in_voltage_scale_available_show(struct device *dev,
809 					       struct device_attribute *attr,
810 					       char *buf)
811 {
812 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
813 	struct ad7606_state *st = iio_priv(indio_dev);
814 	struct ad7606_chan_info *ci = &st->chan_info[0];
815 	const unsigned int (*vals)[2] = ci->scale_avail;
816 	unsigned int i;
817 	size_t len = 0;
818 
819 	for (i = 0; i < ci->num_scales; i++)
820 		len += scnprintf(buf + len, PAGE_SIZE - len, "%u.%06u ",
821 				 vals[i][0], vals[i][1]);
822 	buf[len - 1] = '\n';
823 
824 	return len;
825 }
826 
827 static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
828 
ad7606_write_scale_hw(struct iio_dev * indio_dev,int ch,int val)829 static int ad7606_write_scale_hw(struct iio_dev *indio_dev, int ch, int val)
830 {
831 	struct ad7606_state *st = iio_priv(indio_dev);
832 
833 	gpiod_set_value(st->gpio_range, val);
834 
835 	return 0;
836 }
837 
ad7606_write_os_hw(struct iio_dev * indio_dev,int val)838 static int ad7606_write_os_hw(struct iio_dev *indio_dev, int val)
839 {
840 	struct ad7606_state *st = iio_priv(indio_dev);
841 	DECLARE_BITMAP(values, 3);
842 
843 	values[0] = val & GENMASK(2, 0);
844 
845 	gpiod_multi_set_value_cansleep(st->gpio_os, values);
846 
847 	/* AD7616 requires a reset to update value */
848 	if (st->chip_info->os_req_reset)
849 		ad7606_reset(st);
850 
851 	return 0;
852 }
853 
ad7606_set_calib_offset(struct ad7606_state * st,int ch,int val)854 static int ad7606_set_calib_offset(struct ad7606_state *st, int ch, int val)
855 {
856 	int start_val, step_val, stop_val;
857 	int offset;
858 
859 	start_val = st->chip_info->calib_offset_avail[0];
860 	step_val = st->chip_info->calib_offset_avail[1];
861 	stop_val = st->chip_info->calib_offset_avail[2];
862 
863 	if (val < start_val || val > stop_val)
864 		return -EINVAL;
865 
866 	offset = (val - start_val) / step_val;
867 
868 	return st->bops->reg_write(st, AD7606_CALIB_OFFSET(ch), offset);
869 }
870 
ad7606_set_calib_phase(struct ad7606_state * st,int ch,int val,int val2)871 static int ad7606_set_calib_phase(struct ad7606_state *st, int ch, int val,
872 				  int val2)
873 {
874 	int wreg, start_ns, step_ns, stop_ns;
875 
876 	if (val != 0)
877 		return -EINVAL;
878 
879 	start_ns = st->chip_info->calib_phase_avail[0][1];
880 	step_ns = st->chip_info->calib_phase_avail[1][1];
881 	stop_ns = st->chip_info->calib_phase_avail[2][1];
882 
883 	/*
884 	 * ad7606b: phase delay from 0 to 318.75 μs in steps of 1.25 μs.
885 	 * ad7606c-16/18: phase delay from 0 µs to 255 µs in steps of 1 µs.
886 	 */
887 	if (val2 < start_ns || val2 > stop_ns)
888 		return -EINVAL;
889 
890 	wreg = val2 / step_ns;
891 
892 	return st->bops->reg_write(st, AD7606_CALIB_PHASE(ch), wreg);
893 }
894 
ad7606_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long info)895 static int ad7606_write_raw_get_fmt(struct iio_dev *indio_dev,
896 				    struct iio_chan_spec const *chan, long info)
897 {
898 	switch (info) {
899 	case IIO_CHAN_INFO_SCALE:
900 		return IIO_VAL_INT_PLUS_MICRO;
901 	case IIO_CHAN_INFO_SAMP_FREQ:
902 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
903 	case IIO_CHAN_INFO_CALIBBIAS:
904 		return IIO_VAL_INT;
905 	case IIO_CHAN_INFO_CONVDELAY:
906 		return IIO_VAL_INT_PLUS_NANO;
907 	default:
908 		return -EINVAL;
909 	}
910 }
911 
ad7606_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)912 static int ad7606_write_raw(struct iio_dev *indio_dev,
913 			    struct iio_chan_spec const *chan,
914 			    int val,
915 			    int val2,
916 			    long mask)
917 {
918 	struct ad7606_state *st = iio_priv(indio_dev);
919 	unsigned int scale_avail_uv[AD760X_MAX_SCALES];
920 	struct ad7606_chan_info *ci;
921 	int i, ret, ch = 0;
922 
923 	guard(mutex)(&st->lock);
924 
925 	switch (mask) {
926 	case IIO_CHAN_INFO_SCALE:
927 		if (st->sw_mode_en)
928 			ch = chan->scan_index;
929 		ci = &st->chan_info[ch];
930 		for (i = 0; i < ci->num_scales; i++) {
931 			scale_avail_uv[i] = ci->scale_avail[i][0] * MICRO +
932 					    ci->scale_avail[i][1];
933 		}
934 		val = (val * MICRO) + val2;
935 		i = find_closest(val, scale_avail_uv, ci->num_scales);
936 
937 		if (!iio_device_claim_direct(indio_dev))
938 			return -EBUSY;
939 		ret = st->write_scale(indio_dev, ch, i + ci->reg_offset);
940 		iio_device_release_direct(indio_dev);
941 		if (ret < 0)
942 			return ret;
943 		ci->range = i;
944 
945 		return 0;
946 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
947 		if (val2)
948 			return -EINVAL;
949 		i = find_closest(val, st->oversampling_avail,
950 				 st->num_os_ratios);
951 
952 		if (!iio_device_claim_direct(indio_dev))
953 			return -EBUSY;
954 		ret = st->write_os(indio_dev, i);
955 		iio_device_release_direct(indio_dev);
956 		if (ret < 0)
957 			return ret;
958 		st->oversampling = st->oversampling_avail[i];
959 
960 		return 0;
961 	case IIO_CHAN_INFO_SAMP_FREQ:
962 		if (val < 0 && val2 != 0)
963 			return -EINVAL;
964 		return ad7606_set_sampling_freq(st, val);
965 	case IIO_CHAN_INFO_CALIBBIAS:
966 		if (!iio_device_claim_direct(indio_dev))
967 			return -EBUSY;
968 		ret = ad7606_set_calib_offset(st, chan->scan_index, val);
969 		iio_device_release_direct(indio_dev);
970 		return ret;
971 	case IIO_CHAN_INFO_CONVDELAY:
972 		if (!iio_device_claim_direct(indio_dev))
973 			return -EBUSY;
974 		ret = ad7606_set_calib_phase(st, chan->scan_index, val, val2);
975 		iio_device_release_direct(indio_dev);
976 		return ret;
977 	default:
978 		return -EINVAL;
979 	}
980 }
981 
ad7606_oversampling_ratio_avail(struct device * dev,struct device_attribute * attr,char * buf)982 static ssize_t ad7606_oversampling_ratio_avail(struct device *dev,
983 					       struct device_attribute *attr,
984 					       char *buf)
985 {
986 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
987 	struct ad7606_state *st = iio_priv(indio_dev);
988 	const unsigned int *vals = st->oversampling_avail;
989 	unsigned int i;
990 	size_t len = 0;
991 
992 	for (i = 0; i < st->num_os_ratios; i++)
993 		len += scnprintf(buf + len, PAGE_SIZE - len, "%u ", vals[i]);
994 	buf[len - 1] = '\n';
995 
996 	return len;
997 }
998 
999 static IIO_DEVICE_ATTR(oversampling_ratio_available, 0444,
1000 		       ad7606_oversampling_ratio_avail, NULL, 0);
1001 
1002 static struct attribute *ad7606_attributes_os_and_range[] = {
1003 	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
1004 	&iio_dev_attr_oversampling_ratio_available.dev_attr.attr,
1005 	NULL,
1006 };
1007 
1008 static const struct attribute_group ad7606_attribute_group_os_and_range = {
1009 	.attrs = ad7606_attributes_os_and_range,
1010 };
1011 
1012 static struct attribute *ad7606_attributes_os[] = {
1013 	&iio_dev_attr_oversampling_ratio_available.dev_attr.attr,
1014 	NULL,
1015 };
1016 
1017 static const struct attribute_group ad7606_attribute_group_os = {
1018 	.attrs = ad7606_attributes_os,
1019 };
1020 
1021 static struct attribute *ad7606_attributes_range[] = {
1022 	&iio_dev_attr_in_voltage_scale_available.dev_attr.attr,
1023 	NULL,
1024 };
1025 
1026 static const struct attribute_group ad7606_attribute_group_range = {
1027 	.attrs = ad7606_attributes_range,
1028 };
1029 
ad7606_request_gpios(struct ad7606_state * st)1030 static int ad7606_request_gpios(struct ad7606_state *st)
1031 {
1032 	struct device *dev = st->dev;
1033 
1034 	st->gpio_convst = devm_gpiod_get_optional(dev, "adi,conversion-start",
1035 						  GPIOD_OUT_LOW);
1036 
1037 	if (IS_ERR(st->gpio_convst))
1038 		return PTR_ERR(st->gpio_convst);
1039 
1040 	st->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1041 	if (IS_ERR(st->gpio_reset))
1042 		return PTR_ERR(st->gpio_reset);
1043 
1044 	st->gpio_range = devm_gpiod_get_optional(dev, "adi,range",
1045 						 GPIOD_OUT_LOW);
1046 	if (IS_ERR(st->gpio_range))
1047 		return PTR_ERR(st->gpio_range);
1048 
1049 	st->gpio_standby = devm_gpiod_get_optional(dev, "standby",
1050 						   GPIOD_OUT_LOW);
1051 	if (IS_ERR(st->gpio_standby))
1052 		return PTR_ERR(st->gpio_standby);
1053 
1054 	st->gpio_frstdata = devm_gpiod_get_optional(dev, "adi,first-data",
1055 						    GPIOD_IN);
1056 	if (IS_ERR(st->gpio_frstdata))
1057 		return PTR_ERR(st->gpio_frstdata);
1058 
1059 	if (!st->chip_info->oversampling_num)
1060 		return 0;
1061 
1062 	st->gpio_os = devm_gpiod_get_array_optional(dev,
1063 						    "adi,oversampling-ratio",
1064 						    GPIOD_OUT_LOW);
1065 	return PTR_ERR_OR_ZERO(st->gpio_os);
1066 }
1067 
1068 /*
1069  * The BUSY signal indicates when conversions are in progress, so when a rising
1070  * edge of CONVST is applied, BUSY goes logic high and transitions low at the
1071  * end of the entire conversion process. The falling edge of the BUSY signal
1072  * triggers this interrupt.
1073  */
ad7606_interrupt(int irq,void * dev_id)1074 static irqreturn_t ad7606_interrupt(int irq, void *dev_id)
1075 {
1076 	struct iio_dev *indio_dev = dev_id;
1077 	struct ad7606_state *st = iio_priv(indio_dev);
1078 	int ret;
1079 
1080 	if (iio_buffer_enabled(indio_dev)) {
1081 		if (st->gpio_convst) {
1082 			gpiod_set_value(st->gpio_convst, 0);
1083 		} else {
1084 			ret = ad7606_pwm_set_low(st);
1085 			if (ret < 0) {
1086 				dev_err(st->dev, "PWM set low failed");
1087 				goto done;
1088 			}
1089 		}
1090 		iio_trigger_poll_nested(st->trig);
1091 	} else {
1092 		complete(&st->completion);
1093 	}
1094 
1095 done:
1096 	return IRQ_HANDLED;
1097 };
1098 
ad7606_validate_trigger(struct iio_dev * indio_dev,struct iio_trigger * trig)1099 static int ad7606_validate_trigger(struct iio_dev *indio_dev,
1100 				   struct iio_trigger *trig)
1101 {
1102 	struct ad7606_state *st = iio_priv(indio_dev);
1103 
1104 	if (st->trig != trig)
1105 		return -EINVAL;
1106 
1107 	return 0;
1108 }
1109 
ad7606_buffer_postenable(struct iio_dev * indio_dev)1110 static int ad7606_buffer_postenable(struct iio_dev *indio_dev)
1111 {
1112 	struct ad7606_state *st = iio_priv(indio_dev);
1113 
1114 	gpiod_set_value(st->gpio_convst, 1);
1115 
1116 	return 0;
1117 }
1118 
ad7606_buffer_predisable(struct iio_dev * indio_dev)1119 static int ad7606_buffer_predisable(struct iio_dev *indio_dev)
1120 {
1121 	struct ad7606_state *st = iio_priv(indio_dev);
1122 
1123 	gpiod_set_value(st->gpio_convst, 0);
1124 
1125 	return 0;
1126 }
1127 
ad7606_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long info)1128 static int ad7606_read_avail(struct iio_dev *indio_dev,
1129 			     struct iio_chan_spec const *chan,
1130 			     const int **vals, int *type, int *length,
1131 			     long info)
1132 {
1133 	struct ad7606_state *st = iio_priv(indio_dev);
1134 	struct ad7606_chan_info *ci;
1135 	unsigned int ch = 0;
1136 
1137 	switch (info) {
1138 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1139 		*vals = st->oversampling_avail;
1140 		*length = st->num_os_ratios;
1141 		*type = IIO_VAL_INT;
1142 
1143 		return IIO_AVAIL_LIST;
1144 
1145 	case IIO_CHAN_INFO_SCALE:
1146 		if (st->sw_mode_en)
1147 			ch = chan->scan_index;
1148 
1149 		ci = &st->chan_info[ch];
1150 		*vals = (int *)ci->scale_avail;
1151 		*length = ci->num_scales * 2;
1152 		*type = IIO_VAL_INT_PLUS_MICRO;
1153 
1154 		return IIO_AVAIL_LIST;
1155 	case IIO_CHAN_INFO_CALIBBIAS:
1156 		*vals = st->chip_info->calib_offset_avail;
1157 		*type = IIO_VAL_INT;
1158 		return IIO_AVAIL_RANGE;
1159 	case IIO_CHAN_INFO_CONVDELAY:
1160 		*vals = (const int *)st->chip_info->calib_phase_avail;
1161 		*type = IIO_VAL_INT_PLUS_NANO;
1162 		return IIO_AVAIL_RANGE;
1163 	}
1164 	return -EINVAL;
1165 }
1166 
ad7606_backend_buffer_postenable(struct iio_dev * indio_dev)1167 static int ad7606_backend_buffer_postenable(struct iio_dev *indio_dev)
1168 {
1169 	struct ad7606_state *st = iio_priv(indio_dev);
1170 
1171 	return ad7606_pwm_set_swing(st);
1172 }
1173 
ad7606_backend_buffer_predisable(struct iio_dev * indio_dev)1174 static int ad7606_backend_buffer_predisable(struct iio_dev *indio_dev)
1175 {
1176 	struct ad7606_state *st = iio_priv(indio_dev);
1177 
1178 	return ad7606_pwm_set_low(st);
1179 }
1180 
ad7606_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)1181 static int ad7606_update_scan_mode(struct iio_dev *indio_dev,
1182 				   const unsigned long *scan_mask)
1183 {
1184 	struct ad7606_state *st = iio_priv(indio_dev);
1185 
1186 	/*
1187 	 * The update scan mode is only for iio backend compatible drivers.
1188 	 * If the specific update_scan_mode is not defined in the bus ops,
1189 	 * just do nothing and return 0.
1190 	 */
1191 	if (!st->bops->update_scan_mode)
1192 		return 0;
1193 
1194 	return st->bops->update_scan_mode(indio_dev, scan_mask);
1195 }
1196 
1197 static const struct iio_buffer_setup_ops ad7606_buffer_ops = {
1198 	.postenable = &ad7606_buffer_postenable,
1199 	.predisable = &ad7606_buffer_predisable,
1200 };
1201 
1202 static const struct iio_buffer_setup_ops ad7606_backend_buffer_ops = {
1203 	.postenable = &ad7606_backend_buffer_postenable,
1204 	.predisable = &ad7606_backend_buffer_predisable,
1205 };
1206 
1207 static const struct iio_info ad7606_info_no_os_or_range = {
1208 	.read_raw = &ad7606_read_raw,
1209 	.validate_trigger = &ad7606_validate_trigger,
1210 	.update_scan_mode = &ad7606_update_scan_mode,
1211 };
1212 
1213 static const struct iio_info ad7606_info_os_and_range = {
1214 	.read_raw = &ad7606_read_raw,
1215 	.write_raw = &ad7606_write_raw,
1216 	.attrs = &ad7606_attribute_group_os_and_range,
1217 	.validate_trigger = &ad7606_validate_trigger,
1218 	.update_scan_mode = &ad7606_update_scan_mode,
1219 };
1220 
1221 static const struct iio_info ad7606_info_sw_mode = {
1222 	.read_raw = &ad7606_read_raw,
1223 	.write_raw = &ad7606_write_raw,
1224 	.read_avail = &ad7606_read_avail,
1225 	.write_raw_get_fmt = ad7606_write_raw_get_fmt,
1226 	.debugfs_reg_access = &ad7606_reg_access,
1227 	.validate_trigger = &ad7606_validate_trigger,
1228 	.update_scan_mode = &ad7606_update_scan_mode,
1229 };
1230 
1231 static const struct iio_info ad7606_info_os = {
1232 	.read_raw = &ad7606_read_raw,
1233 	.write_raw = &ad7606_write_raw,
1234 	.attrs = &ad7606_attribute_group_os,
1235 	.validate_trigger = &ad7606_validate_trigger,
1236 	.update_scan_mode = &ad7606_update_scan_mode,
1237 };
1238 
1239 static const struct iio_info ad7606_info_range = {
1240 	.read_raw = &ad7606_read_raw,
1241 	.write_raw = &ad7606_write_raw,
1242 	.attrs = &ad7606_attribute_group_range,
1243 	.validate_trigger = &ad7606_validate_trigger,
1244 	.update_scan_mode = &ad7606_update_scan_mode,
1245 };
1246 
1247 static const struct iio_trigger_ops ad7606_trigger_ops = {
1248 	.validate_device = iio_trigger_validate_own_device,
1249 };
1250 
ad7606_write_mask(struct ad7606_state * st,unsigned int addr,unsigned long mask,unsigned int val)1251 static int ad7606_write_mask(struct ad7606_state *st, unsigned int addr,
1252 			     unsigned long mask, unsigned int val)
1253 {
1254 	int readval;
1255 
1256 	readval = st->bops->reg_read(st, addr);
1257 	if (readval < 0)
1258 		return readval;
1259 
1260 	readval &= ~mask;
1261 	readval |= val;
1262 
1263 	return st->bops->reg_write(st, addr, readval);
1264 }
1265 
ad7616_write_scale_sw(struct iio_dev * indio_dev,int ch,int val)1266 static int ad7616_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
1267 {
1268 	struct ad7606_state *st = iio_priv(indio_dev);
1269 	unsigned int ch_addr, mode, ch_index;
1270 
1271 	/*
1272 	 * Ad7616 has 16 channels divided in group A and group B.
1273 	 * The range of channels from A are stored in registers with address 4
1274 	 * while channels from B are stored in register with address 6.
1275 	 * The last bit from channels determines if it is from group A or B
1276 	 * because the order of channels in iio is 0A, 0B, 1A, 1B...
1277 	 */
1278 	ch_index = ch >> 1;
1279 
1280 	ch_addr = AD7616_RANGE_CH_ADDR(ch_index);
1281 
1282 	if ((ch & 0x1) == 0) /* channel A */
1283 		ch_addr += AD7616_RANGE_CH_A_ADDR_OFF;
1284 	else	/* channel B */
1285 		ch_addr += AD7616_RANGE_CH_B_ADDR_OFF;
1286 
1287 	/* 0b01 for 2.5v, 0b10 for 5v and 0b11 for 10v */
1288 	mode = AD7616_RANGE_CH_MODE(ch_index, ((val + 1) & 0b11));
1289 
1290 	return ad7606_write_mask(st, ch_addr, AD7616_RANGE_CH_MSK(ch_index),
1291 				 mode);
1292 }
1293 
ad7616_write_os_sw(struct iio_dev * indio_dev,int val)1294 static int ad7616_write_os_sw(struct iio_dev *indio_dev, int val)
1295 {
1296 	struct ad7606_state *st = iio_priv(indio_dev);
1297 
1298 	return ad7606_write_mask(st, AD7616_CONFIGURATION_REGISTER,
1299 				 AD7616_OS_MASK, val << 2);
1300 }
1301 
ad7606_write_scale_sw(struct iio_dev * indio_dev,int ch,int val)1302 static int ad7606_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
1303 {
1304 	struct ad7606_state *st = iio_priv(indio_dev);
1305 
1306 	return ad7606_write_mask(st, AD7606_RANGE_CH_ADDR(ch),
1307 				 AD7606_RANGE_CH_MSK(ch),
1308 				 AD7606_RANGE_CH_MODE(ch, val));
1309 }
1310 
ad7606_write_os_sw(struct iio_dev * indio_dev,int val)1311 static int ad7606_write_os_sw(struct iio_dev *indio_dev, int val)
1312 {
1313 	struct ad7606_state *st = iio_priv(indio_dev);
1314 
1315 	return st->bops->reg_write(st, AD7606_OS_MODE, val);
1316 }
1317 
ad7616_sw_mode_setup(struct iio_dev * indio_dev)1318 static int ad7616_sw_mode_setup(struct iio_dev *indio_dev)
1319 {
1320 	struct ad7606_state *st = iio_priv(indio_dev);
1321 	int ret;
1322 
1323 	/*
1324 	 * Scale can be configured individually for each channel
1325 	 * in software mode.
1326 	 */
1327 
1328 	st->write_scale = ad7616_write_scale_sw;
1329 	st->write_os = &ad7616_write_os_sw;
1330 
1331 	if (st->bops->sw_mode_config) {
1332 		ret = st->bops->sw_mode_config(indio_dev);
1333 		if (ret)
1334 			return ret;
1335 	}
1336 
1337 	/* Activate Burst mode and SEQEN MODE */
1338 	return ad7606_write_mask(st, AD7616_CONFIGURATION_REGISTER,
1339 				 AD7616_BURST_MODE | AD7616_SEQEN_MODE,
1340 				 AD7616_BURST_MODE | AD7616_SEQEN_MODE);
1341 }
1342 
ad7606b_sw_mode_setup(struct iio_dev * indio_dev)1343 static int ad7606b_sw_mode_setup(struct iio_dev *indio_dev)
1344 {
1345 	struct ad7606_state *st = iio_priv(indio_dev);
1346 	DECLARE_BITMAP(os, 3);
1347 
1348 	bitmap_fill(os, 3);
1349 	/*
1350 	 * Software mode is enabled when all three oversampling
1351 	 * pins are set to high. If oversampling gpios are defined
1352 	 * in the device tree, then they need to be set to high,
1353 	 * otherwise, they must be hardwired to VDD
1354 	 */
1355 	if (st->gpio_os)
1356 		gpiod_multi_set_value_cansleep(st->gpio_os, os);
1357 
1358 	/* OS of 128 and 256 are available only in software mode */
1359 	st->oversampling_avail = ad7606b_oversampling_avail;
1360 	st->num_os_ratios = ARRAY_SIZE(ad7606b_oversampling_avail);
1361 
1362 	st->write_scale = ad7606_write_scale_sw;
1363 	st->write_os = &ad7606_write_os_sw;
1364 
1365 	if (!st->bops->sw_mode_config)
1366 		return 0;
1367 
1368 	return st->bops->sw_mode_config(indio_dev);
1369 }
1370 
ad7606_set_gain_calib(struct ad7606_state * st)1371 static int ad7606_set_gain_calib(struct ad7606_state *st)
1372 {
1373 	struct ad7606_chan_info *ci;
1374 	int i, ret;
1375 
1376 	for (i = 0; i < st->chip_info->num_adc_channels; i++) {
1377 		ci = &st->chan_info[i];
1378 		ret = st->bops->reg_write(st, AD7606_CALIB_GAIN(i),
1379 					  DIV_ROUND_CLOSEST(ci->r_gain,
1380 						AD7606_CALIB_GAIN_STEP));
1381 		if (ret)
1382 			return ret;
1383 	}
1384 
1385 	return 0;
1386 }
1387 
ad7606_probe_channels(struct iio_dev * indio_dev)1388 static int ad7606_probe_channels(struct iio_dev *indio_dev)
1389 {
1390 	struct ad7606_state *st = iio_priv(indio_dev);
1391 	struct device *dev = indio_dev->dev.parent;
1392 	struct iio_chan_spec *channels;
1393 	bool slow_bus;
1394 	int ret, i;
1395 
1396 	slow_bus = !(st->bops->iio_backend_config || st->offload_en);
1397 	indio_dev->num_channels = st->chip_info->num_adc_channels;
1398 
1399 	/* Slow buses also get 1 more channel for soft timestamp */
1400 	if (slow_bus)
1401 		indio_dev->num_channels++;
1402 
1403 	channels = devm_kcalloc(dev, indio_dev->num_channels, sizeof(*channels),
1404 				GFP_KERNEL);
1405 	if (!channels)
1406 		return -ENOMEM;
1407 
1408 	for (i = 0; i < st->chip_info->num_adc_channels; i++) {
1409 		struct iio_chan_spec *chan = &channels[i];
1410 
1411 		chan->type = IIO_VOLTAGE;
1412 		chan->indexed = 1;
1413 		chan->channel = i;
1414 		chan->scan_index = i;
1415 		chan->scan_type.sign = 's';
1416 		chan->scan_type.realbits = st->chip_info->bits;
1417 		/*
1418 		 * If in SPI offload mode, storagebits are set based
1419 		 * on the spi-engine hw implementation.
1420 		 */
1421 		chan->scan_type.storagebits = st->offload_en ?
1422 			st->chip_info->offload_storagebits :
1423 			(st->chip_info->bits > 16 ? 32 : 16);
1424 
1425 		chan->scan_type.endianness = IIO_CPU;
1426 
1427 		if (indio_dev->modes & INDIO_DIRECT_MODE)
1428 			chan->info_mask_separate |= BIT(IIO_CHAN_INFO_RAW);
1429 
1430 		if (st->sw_mode_en) {
1431 			chan->info_mask_separate |= BIT(IIO_CHAN_INFO_SCALE);
1432 			chan->info_mask_separate_available |=
1433 				BIT(IIO_CHAN_INFO_SCALE);
1434 
1435 			if (st->chip_info->calib_offset_avail) {
1436 				chan->info_mask_separate |=
1437 					BIT(IIO_CHAN_INFO_CALIBBIAS) |
1438 					BIT(IIO_CHAN_INFO_CONVDELAY);
1439 				chan->info_mask_separate_available |=
1440 					BIT(IIO_CHAN_INFO_CALIBBIAS) |
1441 					BIT(IIO_CHAN_INFO_CONVDELAY);
1442 			}
1443 
1444 			/*
1445 			 * All chips with software mode support oversampling,
1446 			 * so we skip the oversampling_available check. And the
1447 			 * shared_by_type instead of shared_by_all on slow
1448 			 * buses is for backward compatibility.
1449 			 */
1450 			if (slow_bus)
1451 				chan->info_mask_shared_by_type |=
1452 					BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
1453 			else
1454 				chan->info_mask_shared_by_all |=
1455 					BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
1456 
1457 			chan->info_mask_shared_by_all_available |=
1458 				BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
1459 		} else {
1460 			chan->info_mask_shared_by_type |=
1461 				BIT(IIO_CHAN_INFO_SCALE);
1462 
1463 			if (st->chip_info->oversampling_avail)
1464 				chan->info_mask_shared_by_all |=
1465 					BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
1466 		}
1467 
1468 		if (!slow_bus)
1469 			chan->info_mask_shared_by_all |=
1470 				BIT(IIO_CHAN_INFO_SAMP_FREQ);
1471 
1472 		ret = st->chip_info->scale_setup_cb(indio_dev, chan);
1473 		if (ret)
1474 			return ret;
1475 	}
1476 
1477 	if (slow_bus)
1478 		channels[i] = (struct iio_chan_spec)IIO_CHAN_SOFT_TIMESTAMP(i);
1479 
1480 	indio_dev->channels = channels;
1481 
1482 	return 0;
1483 }
1484 
ad7606_pwm_disable(void * data)1485 static void ad7606_pwm_disable(void *data)
1486 {
1487 	pwm_disable(data);
1488 }
1489 
ad7606_probe(struct device * dev,int irq,void __iomem * base_address,const struct ad7606_chip_info * chip_info,const struct ad7606_bus_ops * bops)1490 int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
1491 		 const struct ad7606_chip_info *chip_info,
1492 		 const struct ad7606_bus_ops *bops)
1493 {
1494 	struct ad7606_state *st;
1495 	int ret;
1496 	struct iio_dev *indio_dev;
1497 
1498 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1499 	if (!indio_dev)
1500 		return -ENOMEM;
1501 
1502 	st = iio_priv(indio_dev);
1503 	dev_set_drvdata(dev, indio_dev);
1504 
1505 	ret = devm_mutex_init(dev, &st->lock);
1506 	if (ret)
1507 		return ret;
1508 
1509 	st->dev = dev;
1510 	st->bops = bops;
1511 	st->base_address = base_address;
1512 	st->oversampling = 1;
1513 	st->sw_mode_en = device_property_read_bool(dev, "adi,sw-mode");
1514 
1515 	if (st->sw_mode_en && !chip_info->sw_setup_cb)
1516 		return dev_err_probe(dev, -EINVAL,
1517 			"Software mode is not supported for this chip\n");
1518 
1519 	ret = devm_regulator_get_enable(dev, "avcc");
1520 	if (ret)
1521 		return dev_err_probe(dev, ret,
1522 				     "Failed to enable specified AVcc supply\n");
1523 
1524 	ret = devm_regulator_get_enable(dev, "vdrive");
1525 	if (ret)
1526 		return dev_err_probe(dev, ret,
1527 				     "Failed to enable Vdrive supply\n");
1528 
1529 	ret = devm_regulator_get_enable_optional(dev, "refin");
1530 	if (ret && ret != -ENODEV)
1531 		return dev_err_probe(dev, ret,
1532 				     "Failed to enable REFIN supply\n");
1533 
1534 	st->chip_info = chip_info;
1535 
1536 	if (st->chip_info->oversampling_num) {
1537 		st->oversampling_avail = st->chip_info->oversampling_avail;
1538 		st->num_os_ratios = st->chip_info->oversampling_num;
1539 	}
1540 
1541 	ret = ad7606_request_gpios(st);
1542 	if (ret)
1543 		return ret;
1544 
1545 	if (st->gpio_os) {
1546 		if (st->gpio_range)
1547 			indio_dev->info = &ad7606_info_os_and_range;
1548 		else
1549 			indio_dev->info = &ad7606_info_os;
1550 	} else {
1551 		if (st->gpio_range)
1552 			indio_dev->info = &ad7606_info_range;
1553 		else
1554 			indio_dev->info = &ad7606_info_no_os_or_range;
1555 	}
1556 
1557 	/* AXI ADC backend doesn't support single read. */
1558 	indio_dev->modes = st->bops->iio_backend_config ? 0 : INDIO_DIRECT_MODE;
1559 	indio_dev->name = chip_info->name;
1560 
1561 	/* Using spi-engine with offload support ? */
1562 	if (st->bops->offload_config) {
1563 		ret = st->bops->offload_config(dev, indio_dev);
1564 		if (ret)
1565 			return ret;
1566 	}
1567 
1568 	ret = ad7606_probe_channels(indio_dev);
1569 	if (ret)
1570 		return ret;
1571 
1572 	ret = ad7606_reset(st);
1573 	if (ret)
1574 		dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
1575 
1576 	/* AD7616 requires al least 15ms to reconfigure after a reset */
1577 	if (st->chip_info->init_delay_ms) {
1578 		if (msleep_interruptible(st->chip_info->init_delay_ms))
1579 			return -ERESTARTSYS;
1580 	}
1581 
1582 	/* If convst pin is not defined, setup PWM. */
1583 	if (!st->gpio_convst || st->offload_en) {
1584 		st->cnvst_pwm = devm_pwm_get(dev, NULL);
1585 		if (IS_ERR(st->cnvst_pwm))
1586 			return PTR_ERR(st->cnvst_pwm);
1587 
1588 		/* The PWM is initialized at 1MHz to have a fast enough GPIO emulation. */
1589 		ret = ad7606_set_sampling_freq(st, 1 * MEGA);
1590 		if (ret)
1591 			return ret;
1592 
1593 		ret = ad7606_pwm_set_low(st);
1594 		if (ret)
1595 			return ret;
1596 
1597 		/*
1598 		 * PWM is not disabled when sampling stops, but instead its duty cycle is set
1599 		 * to 0% to be sure we have a "low" state. After we unload the driver, let's
1600 		 * disable the PWM.
1601 		 */
1602 		ret = devm_add_action_or_reset(dev, ad7606_pwm_disable,
1603 					       st->cnvst_pwm);
1604 		if (ret)
1605 			return ret;
1606 	}
1607 
1608 	if (st->bops->iio_backend_config) {
1609 		/*
1610 		 * If there is a backend, the PWM should not overpass the maximum sampling
1611 		 * frequency the chip supports.
1612 		 */
1613 		ret = ad7606_set_sampling_freq(st, chip_info->max_samplerate);
1614 		if (ret)
1615 			return ret;
1616 
1617 		ret = st->bops->iio_backend_config(dev, indio_dev);
1618 		if (ret)
1619 			return ret;
1620 
1621 		indio_dev->setup_ops = &ad7606_backend_buffer_ops;
1622 	} else if (!st->offload_en) {
1623 		/* Reserve the PWM use only for backend (force gpio_convst definition) */
1624 		if (!st->gpio_convst)
1625 			return dev_err_probe(dev, -EINVAL,
1626 					     "No backend, connect convst to a GPIO");
1627 
1628 		init_completion(&st->completion);
1629 		st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
1630 						  indio_dev->name,
1631 						  iio_device_id(indio_dev));
1632 		if (!st->trig)
1633 			return -ENOMEM;
1634 
1635 		st->trig->ops = &ad7606_trigger_ops;
1636 		iio_trigger_set_drvdata(st->trig, indio_dev);
1637 		ret = devm_iio_trigger_register(dev, st->trig);
1638 		if (ret)
1639 			return ret;
1640 
1641 		indio_dev->trig = iio_trigger_get(st->trig);
1642 
1643 		ret = devm_request_threaded_irq(dev, irq, NULL, &ad7606_interrupt,
1644 						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
1645 						chip_info->name, indio_dev);
1646 		if (ret)
1647 			return ret;
1648 
1649 		ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
1650 						      &iio_pollfunc_store_time,
1651 						      &ad7606_trigger_handler,
1652 						      &ad7606_buffer_ops);
1653 		if (ret)
1654 			return ret;
1655 	}
1656 
1657 	st->write_scale = ad7606_write_scale_hw;
1658 	st->write_os = ad7606_write_os_hw;
1659 
1660 	/* Offload needs 1 DOUT line, applying this setting in sw_setup_cb. */
1661 	if (st->sw_mode_en || st->offload_en) {
1662 		indio_dev->info = &ad7606_info_sw_mode;
1663 		st->chip_info->sw_setup_cb(indio_dev);
1664 	}
1665 
1666 	if (st->sw_mode_en && st->chip_info->calib_gain_avail) {
1667 		ret = ad7606_set_gain_calib(st);
1668 		if (ret)
1669 			return ret;
1670 	}
1671 
1672 	return devm_iio_device_register(dev, indio_dev);
1673 }
1674 EXPORT_SYMBOL_NS_GPL(ad7606_probe, "IIO_AD7606");
1675 
1676 #ifdef CONFIG_PM_SLEEP
1677 
ad7606_suspend(struct device * dev)1678 static int ad7606_suspend(struct device *dev)
1679 {
1680 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1681 	struct ad7606_state *st = iio_priv(indio_dev);
1682 
1683 	if (st->gpio_standby) {
1684 		gpiod_set_value(st->gpio_range, 1);
1685 		gpiod_set_value(st->gpio_standby, 1);
1686 	}
1687 
1688 	return 0;
1689 }
1690 
ad7606_resume(struct device * dev)1691 static int ad7606_resume(struct device *dev)
1692 {
1693 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1694 	struct ad7606_state *st = iio_priv(indio_dev);
1695 
1696 	if (st->gpio_standby) {
1697 		gpiod_set_value(st->gpio_range, st->chan_info[0].range);
1698 		gpiod_set_value(st->gpio_standby, 1);
1699 		ad7606_reset(st);
1700 	}
1701 
1702 	return 0;
1703 }
1704 
1705 SIMPLE_DEV_PM_OPS(ad7606_pm_ops, ad7606_suspend, ad7606_resume);
1706 EXPORT_SYMBOL_NS_GPL(ad7606_pm_ops, "IIO_AD7606");
1707 
1708 #endif
1709 
1710 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1711 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
1712 MODULE_LICENSE("GPL v2");
1713