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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2021 Analog Devices, Inc.
4  * Author: Cosmin Tanislav <cosmin.tanislav@analog.com>
5  */
6 
7 #include <asm/unaligned.h>
8 #include <linux/bitfield.h>
9 #include <linux/crc8.h>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/iio/buffer.h>
14 #include <linux/iio/iio.h>
15 #include <linux/iio/sysfs.h>
16 #include <linux/iio/trigger.h>
17 #include <linux/iio/trigger_consumer.h>
18 #include <linux/iio/triggered_buffer.h>
19 #include <linux/interrupt.h>
20 #include <linux/mod_devicetable.h>
21 #include <linux/property.h>
22 #include <linux/regmap.h>
23 #include <linux/regulator/consumer.h>
24 #include <linux/spi/spi.h>
25 
26 #include <dt-bindings/iio/addac/adi,ad74413r.h>
27 
28 #define AD74413R_CRC_POLYNOMIAL	0x7
29 DECLARE_CRC8_TABLE(ad74413r_crc8_table);
30 
31 #define AD74413R_CHANNEL_MAX	4
32 
33 #define AD74413R_FRAME_SIZE	4
34 
35 struct ad74413r_chip_info {
36 	const char	*name;
37 	bool		hart_support;
38 };
39 
40 struct ad74413r_channel_config {
41 	u32		func;
42 	u32		drive_strength;
43 	bool		gpo_comparator;
44 	bool		initialized;
45 };
46 
47 struct ad74413r_channels {
48 	struct iio_chan_spec	*channels;
49 	unsigned int		num_channels;
50 };
51 
52 struct ad74413r_state {
53 	struct ad74413r_channel_config	channel_configs[AD74413R_CHANNEL_MAX];
54 	unsigned int			gpo_gpio_offsets[AD74413R_CHANNEL_MAX];
55 	unsigned int			comp_gpio_offsets[AD74413R_CHANNEL_MAX];
56 	struct gpio_chip		gpo_gpiochip;
57 	struct gpio_chip		comp_gpiochip;
58 	struct completion		adc_data_completion;
59 	unsigned int			num_gpo_gpios;
60 	unsigned int			num_comparator_gpios;
61 	u32				sense_resistor_ohms;
62 
63 	/*
64 	 * Synchronize consecutive operations when doing a one-shot
65 	 * conversion and when updating the ADC samples SPI message.
66 	 */
67 	struct mutex			lock;
68 
69 	const struct ad74413r_chip_info	*chip_info;
70 	struct spi_device		*spi;
71 	struct regulator		*refin_reg;
72 	struct regmap			*regmap;
73 	struct device			*dev;
74 	struct iio_trigger		*trig;
75 	struct gpio_desc		*reset_gpio;
76 
77 	size_t			adc_active_channels;
78 	struct spi_message	adc_samples_msg;
79 	struct spi_transfer	adc_samples_xfer[AD74413R_CHANNEL_MAX + 1];
80 
81 	/*
82 	 * DMA (thus cache coherency maintenance) may require the
83 	 * transfer buffers to live in their own cache lines.
84 	 */
85 	struct {
86 		u8 rx_buf[AD74413R_FRAME_SIZE * AD74413R_CHANNEL_MAX];
87 		s64 timestamp;
88 	} adc_samples_buf __aligned(IIO_DMA_MINALIGN);
89 
90 	u8	adc_samples_tx_buf[AD74413R_FRAME_SIZE * AD74413R_CHANNEL_MAX];
91 	u8	reg_tx_buf[AD74413R_FRAME_SIZE];
92 	u8	reg_rx_buf[AD74413R_FRAME_SIZE];
93 };
94 
95 #define AD74413R_REG_NOP		0x00
96 
97 #define AD74413R_REG_CH_FUNC_SETUP_X(x)	(0x01 + (x))
98 #define AD74413R_CH_FUNC_SETUP_MASK	GENMASK(3, 0)
99 
100 #define AD74413R_REG_ADC_CONFIG_X(x)		(0x05 + (x))
101 #define AD74413R_ADC_CONFIG_RANGE_MASK		GENMASK(7, 5)
102 #define AD74413R_ADC_CONFIG_REJECTION_MASK	GENMASK(4, 3)
103 #define AD74413R_ADC_CONFIG_CH_200K_TO_GND	BIT(2)
104 #define AD74413R_ADC_RANGE_10V			0b000
105 #define AD74413R_ADC_RANGE_2P5V_EXT_POW		0b001
106 #define AD74413R_ADC_RANGE_2P5V_INT_POW		0b010
107 #define AD74413R_ADC_RANGE_5V_BI_DIR		0b011
108 #define AD74413R_ADC_REJECTION_50_60		0b00
109 #define AD74413R_ADC_REJECTION_NONE		0b01
110 #define AD74413R_ADC_REJECTION_50_60_HART	0b10
111 #define AD74413R_ADC_REJECTION_HART		0b11
112 
113 #define AD74413R_REG_DIN_CONFIG_X(x)	(0x09 + (x))
114 #define AD74413R_DIN_DEBOUNCE_MASK	GENMASK(4, 0)
115 #define AD74413R_DIN_DEBOUNCE_LEN	BIT(5)
116 #define AD74413R_DIN_SINK_MASK		GENMASK(9, 6)
117 
118 #define AD74413R_REG_DAC_CODE_X(x)	(0x16 + (x))
119 #define AD74413R_DAC_CODE_MAX		GENMASK(12, 0)
120 #define AD74413R_DAC_VOLTAGE_MAX	11000
121 
122 #define AD74413R_REG_GPO_PAR_DATA		0x0d
123 #define AD74413R_REG_GPO_CONFIG_X(x)		(0x0e + (x))
124 #define AD74413R_GPO_CONFIG_DATA_MASK	BIT(3)
125 #define AD74413R_GPO_CONFIG_SELECT_MASK		GENMASK(2, 0)
126 #define AD74413R_GPO_CONFIG_100K_PULL_DOWN	0b000
127 #define AD74413R_GPO_CONFIG_LOGIC		0b001
128 #define AD74413R_GPO_CONFIG_LOGIC_PARALLEL	0b010
129 #define AD74413R_GPO_CONFIG_COMPARATOR		0b011
130 #define AD74413R_GPO_CONFIG_HIGH_IMPEDANCE	0b100
131 
132 #define AD74413R_REG_ADC_CONV_CTRL	0x23
133 #define AD74413R_CONV_SEQ_MASK		GENMASK(9, 8)
134 #define AD74413R_CONV_SEQ_ON		0b00
135 #define AD74413R_CONV_SEQ_SINGLE	0b01
136 #define AD74413R_CONV_SEQ_CONTINUOUS	0b10
137 #define AD74413R_CONV_SEQ_OFF		0b11
138 #define AD74413R_CH_EN_MASK(x)		BIT(x)
139 
140 #define AD74413R_REG_DIN_COMP_OUT		0x25
141 
142 #define AD74413R_REG_ADC_RESULT_X(x)	(0x26 + (x))
143 #define AD74413R_ADC_RESULT_MAX		GENMASK(15, 0)
144 
145 #define AD74413R_REG_READ_SELECT	0x41
146 
147 #define AD74413R_REG_CMD_KEY		0x44
148 #define AD74413R_CMD_KEY_LDAC		0x953a
149 #define AD74413R_CMD_KEY_RESET1		0x15fa
150 #define AD74413R_CMD_KEY_RESET2		0xaf51
151 
152 static const int ad74413r_adc_sampling_rates[] = {
153 	20, 4800,
154 };
155 
156 static const int ad74413r_adc_sampling_rates_hart[] = {
157 	10, 20, 1200, 4800,
158 };
159 
ad74413r_crc(u8 * buf)160 static int ad74413r_crc(u8 *buf)
161 {
162 	return crc8(ad74413r_crc8_table, buf, 3, 0);
163 }
164 
ad74413r_format_reg_write(u8 reg,u16 val,u8 * buf)165 static void ad74413r_format_reg_write(u8 reg, u16 val, u8 *buf)
166 {
167 	buf[0] = reg;
168 	put_unaligned_be16(val, &buf[1]);
169 	buf[3] = ad74413r_crc(buf);
170 }
171 
ad74413r_reg_write(void * context,unsigned int reg,unsigned int val)172 static int ad74413r_reg_write(void *context, unsigned int reg, unsigned int val)
173 {
174 	struct ad74413r_state *st = context;
175 
176 	ad74413r_format_reg_write(reg, val, st->reg_tx_buf);
177 
178 	return spi_write(st->spi, st->reg_tx_buf, AD74413R_FRAME_SIZE);
179 }
180 
ad74413r_crc_check(struct ad74413r_state * st,u8 * buf)181 static int ad74413r_crc_check(struct ad74413r_state *st, u8 *buf)
182 {
183 	u8 expected_crc = ad74413r_crc(buf);
184 
185 	if (buf[3] != expected_crc) {
186 		dev_err(st->dev, "Bad CRC %02x for %02x%02x%02x\n",
187 			buf[3], buf[0], buf[1], buf[2]);
188 		return -EINVAL;
189 	}
190 
191 	return 0;
192 }
193 
ad74413r_reg_read(void * context,unsigned int reg,unsigned int * val)194 static int ad74413r_reg_read(void *context, unsigned int reg, unsigned int *val)
195 {
196 	struct ad74413r_state *st = context;
197 	struct spi_transfer reg_read_xfer[] = {
198 		{
199 			.tx_buf = st->reg_tx_buf,
200 			.len = AD74413R_FRAME_SIZE,
201 			.cs_change = 1,
202 		},
203 		{
204 			.rx_buf = st->reg_rx_buf,
205 			.len = AD74413R_FRAME_SIZE,
206 		},
207 	};
208 	int ret;
209 
210 	ad74413r_format_reg_write(AD74413R_REG_READ_SELECT, reg,
211 				  st->reg_tx_buf);
212 
213 	ret = spi_sync_transfer(st->spi, reg_read_xfer,
214 				ARRAY_SIZE(reg_read_xfer));
215 	if (ret)
216 		return ret;
217 
218 	ret = ad74413r_crc_check(st, st->reg_rx_buf);
219 	if (ret)
220 		return ret;
221 
222 	*val = get_unaligned_be16(&st->reg_rx_buf[1]);
223 
224 	return 0;
225 }
226 
227 static const struct regmap_config ad74413r_regmap_config = {
228 	.reg_bits = 8,
229 	.val_bits = 16,
230 	.reg_read = ad74413r_reg_read,
231 	.reg_write = ad74413r_reg_write,
232 };
233 
ad74413r_set_gpo_config(struct ad74413r_state * st,unsigned int offset,u8 mode)234 static int ad74413r_set_gpo_config(struct ad74413r_state *st,
235 				   unsigned int offset, u8 mode)
236 {
237 	return regmap_update_bits(st->regmap, AD74413R_REG_GPO_CONFIG_X(offset),
238 				  AD74413R_GPO_CONFIG_SELECT_MASK, mode);
239 }
240 
241 static const unsigned int ad74413r_debounce_map[AD74413R_DIN_DEBOUNCE_LEN] = {
242 	0,     13,    18,    24,    32,    42,    56,    75,
243 	100,   130,   180,   240,   320,   420,   560,   750,
244 	1000,  1300,  1800,  2400,  3200,  4200,  5600,  7500,
245 	10000, 13000, 18000, 24000, 32000, 42000, 56000, 75000,
246 };
247 
ad74413r_set_comp_debounce(struct ad74413r_state * st,unsigned int offset,unsigned int debounce)248 static int ad74413r_set_comp_debounce(struct ad74413r_state *st,
249 				      unsigned int offset,
250 				      unsigned int debounce)
251 {
252 	unsigned int val = AD74413R_DIN_DEBOUNCE_LEN - 1;
253 	unsigned int i;
254 
255 	for (i = 0; i < AD74413R_DIN_DEBOUNCE_LEN; i++)
256 		if (debounce <= ad74413r_debounce_map[i]) {
257 			val = i;
258 			break;
259 		}
260 
261 	return regmap_update_bits(st->regmap,
262 				  AD74413R_REG_DIN_CONFIG_X(offset),
263 				  AD74413R_DIN_DEBOUNCE_MASK,
264 				  val);
265 }
266 
ad74413r_set_comp_drive_strength(struct ad74413r_state * st,unsigned int offset,unsigned int strength)267 static int ad74413r_set_comp_drive_strength(struct ad74413r_state *st,
268 					    unsigned int offset,
269 					    unsigned int strength)
270 {
271 	strength = min(strength, 1800U);
272 
273 	return regmap_update_bits(st->regmap, AD74413R_REG_DIN_CONFIG_X(offset),
274 				  AD74413R_DIN_SINK_MASK,
275 				  FIELD_PREP(AD74413R_DIN_SINK_MASK, strength / 120));
276 }
277 
278 
ad74413r_gpio_set(struct gpio_chip * chip,unsigned int offset,int val)279 static void ad74413r_gpio_set(struct gpio_chip *chip,
280 			      unsigned int offset, int val)
281 {
282 	struct ad74413r_state *st = gpiochip_get_data(chip);
283 	unsigned int real_offset = st->gpo_gpio_offsets[offset];
284 	int ret;
285 
286 	ret = ad74413r_set_gpo_config(st, real_offset,
287 				      AD74413R_GPO_CONFIG_LOGIC);
288 	if (ret)
289 		return;
290 
291 	regmap_update_bits(st->regmap, AD74413R_REG_GPO_CONFIG_X(real_offset),
292 			   AD74413R_GPO_CONFIG_DATA_MASK,
293 			   val ? AD74413R_GPO_CONFIG_DATA_MASK : 0);
294 }
295 
ad74413r_gpio_set_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)296 static void ad74413r_gpio_set_multiple(struct gpio_chip *chip,
297 				       unsigned long *mask,
298 				       unsigned long *bits)
299 {
300 	struct ad74413r_state *st = gpiochip_get_data(chip);
301 	unsigned long real_mask = 0;
302 	unsigned long real_bits = 0;
303 	unsigned int offset;
304 	int ret;
305 
306 	for_each_set_bit(offset, mask, chip->ngpio) {
307 		unsigned int real_offset = st->gpo_gpio_offsets[offset];
308 
309 		ret = ad74413r_set_gpo_config(st, real_offset,
310 			AD74413R_GPO_CONFIG_LOGIC_PARALLEL);
311 		if (ret)
312 			return;
313 
314 		real_mask |= BIT(real_offset);
315 		if (*bits & offset)
316 			real_bits |= BIT(real_offset);
317 	}
318 
319 	regmap_update_bits(st->regmap, AD74413R_REG_GPO_PAR_DATA,
320 			   real_mask, real_bits);
321 }
322 
ad74413r_gpio_get(struct gpio_chip * chip,unsigned int offset)323 static int ad74413r_gpio_get(struct gpio_chip *chip, unsigned int offset)
324 {
325 	struct ad74413r_state *st = gpiochip_get_data(chip);
326 	unsigned int real_offset = st->comp_gpio_offsets[offset];
327 	unsigned int status;
328 	int ret;
329 
330 	ret = regmap_read(st->regmap, AD74413R_REG_DIN_COMP_OUT, &status);
331 	if (ret)
332 		return ret;
333 
334 	status &= BIT(real_offset);
335 
336 	return status ? 1 : 0;
337 }
338 
ad74413r_gpio_get_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)339 static int ad74413r_gpio_get_multiple(struct gpio_chip *chip,
340 				      unsigned long *mask,
341 				      unsigned long *bits)
342 {
343 	struct ad74413r_state *st = gpiochip_get_data(chip);
344 	unsigned int offset;
345 	unsigned int val;
346 	int ret;
347 
348 	ret = regmap_read(st->regmap, AD74413R_REG_DIN_COMP_OUT, &val);
349 	if (ret)
350 		return ret;
351 
352 	for_each_set_bit(offset, mask, chip->ngpio) {
353 		unsigned int real_offset = st->comp_gpio_offsets[offset];
354 
355 		__assign_bit(offset, bits, val & BIT(real_offset));
356 	}
357 
358 	return ret;
359 }
360 
ad74413r_gpio_get_gpo_direction(struct gpio_chip * chip,unsigned int offset)361 static int ad74413r_gpio_get_gpo_direction(struct gpio_chip *chip,
362 					   unsigned int offset)
363 {
364 	return GPIO_LINE_DIRECTION_OUT;
365 }
366 
ad74413r_gpio_get_comp_direction(struct gpio_chip * chip,unsigned int offset)367 static int ad74413r_gpio_get_comp_direction(struct gpio_chip *chip,
368 					    unsigned int offset)
369 {
370 	return GPIO_LINE_DIRECTION_IN;
371 }
372 
ad74413r_gpio_set_gpo_config(struct gpio_chip * chip,unsigned int offset,unsigned long config)373 static int ad74413r_gpio_set_gpo_config(struct gpio_chip *chip,
374 					unsigned int offset,
375 					unsigned long config)
376 {
377 	struct ad74413r_state *st = gpiochip_get_data(chip);
378 	unsigned int real_offset = st->gpo_gpio_offsets[offset];
379 
380 	switch (pinconf_to_config_param(config)) {
381 	case PIN_CONFIG_BIAS_PULL_DOWN:
382 		return ad74413r_set_gpo_config(st, real_offset,
383 			AD74413R_GPO_CONFIG_100K_PULL_DOWN);
384 	case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
385 		return ad74413r_set_gpo_config(st, real_offset,
386 			AD74413R_GPO_CONFIG_HIGH_IMPEDANCE);
387 	default:
388 		return -ENOTSUPP;
389 	}
390 }
391 
ad74413r_gpio_set_comp_config(struct gpio_chip * chip,unsigned int offset,unsigned long config)392 static int ad74413r_gpio_set_comp_config(struct gpio_chip *chip,
393 					 unsigned int offset,
394 					 unsigned long config)
395 {
396 	struct ad74413r_state *st = gpiochip_get_data(chip);
397 	unsigned int real_offset = st->comp_gpio_offsets[offset];
398 
399 	switch (pinconf_to_config_param(config)) {
400 	case PIN_CONFIG_INPUT_DEBOUNCE:
401 		return ad74413r_set_comp_debounce(st, real_offset,
402 			pinconf_to_config_argument(config));
403 	default:
404 		return -ENOTSUPP;
405 	}
406 }
407 
ad74413r_reset(struct ad74413r_state * st)408 static int ad74413r_reset(struct ad74413r_state *st)
409 {
410 	int ret;
411 
412 	if (st->reset_gpio) {
413 		gpiod_set_value_cansleep(st->reset_gpio, 1);
414 		fsleep(50);
415 		gpiod_set_value_cansleep(st->reset_gpio, 0);
416 		return 0;
417 	}
418 
419 	ret = regmap_write(st->regmap, AD74413R_REG_CMD_KEY,
420 			   AD74413R_CMD_KEY_RESET1);
421 	if (ret)
422 		return ret;
423 
424 	return regmap_write(st->regmap, AD74413R_REG_CMD_KEY,
425 			    AD74413R_CMD_KEY_RESET2);
426 }
427 
ad74413r_set_channel_dac_code(struct ad74413r_state * st,unsigned int channel,int dac_code)428 static int ad74413r_set_channel_dac_code(struct ad74413r_state *st,
429 					 unsigned int channel, int dac_code)
430 {
431 	struct reg_sequence reg_seq[2] = {
432 		{ AD74413R_REG_DAC_CODE_X(channel), dac_code },
433 		{ AD74413R_REG_CMD_KEY, AD74413R_CMD_KEY_LDAC },
434 	};
435 
436 	return regmap_multi_reg_write(st->regmap, reg_seq, 2);
437 }
438 
ad74413r_set_channel_function(struct ad74413r_state * st,unsigned int channel,u8 func)439 static int ad74413r_set_channel_function(struct ad74413r_state *st,
440 					 unsigned int channel, u8 func)
441 {
442 	int ret;
443 
444 	ret = regmap_update_bits(st->regmap,
445 				  AD74413R_REG_CH_FUNC_SETUP_X(channel),
446 				  AD74413R_CH_FUNC_SETUP_MASK, func);
447 	if (ret)
448 		return ret;
449 
450 	if (func == CH_FUNC_CURRENT_INPUT_LOOP_POWER)
451 		ret = regmap_set_bits(st->regmap,
452 				      AD74413R_REG_ADC_CONFIG_X(channel),
453 				      AD74413R_ADC_CONFIG_CH_200K_TO_GND);
454 
455 	return ret;
456 }
457 
ad74413r_set_adc_conv_seq(struct ad74413r_state * st,unsigned int status)458 static int ad74413r_set_adc_conv_seq(struct ad74413r_state *st,
459 				     unsigned int status)
460 {
461 	int ret;
462 
463 	/*
464 	 * These bits do not clear when a conversion completes.
465 	 * To enable a subsequent conversion, repeat the write.
466 	 */
467 	ret = regmap_write_bits(st->regmap, AD74413R_REG_ADC_CONV_CTRL,
468 				AD74413R_CONV_SEQ_MASK,
469 				FIELD_PREP(AD74413R_CONV_SEQ_MASK, status));
470 	if (ret)
471 		return ret;
472 
473 	/*
474 	 * Wait 100us before starting conversions.
475 	 */
476 	usleep_range(100, 120);
477 
478 	return 0;
479 }
480 
ad74413r_set_adc_channel_enable(struct ad74413r_state * st,unsigned int channel,bool status)481 static int ad74413r_set_adc_channel_enable(struct ad74413r_state *st,
482 					   unsigned int channel,
483 					   bool status)
484 {
485 	return regmap_update_bits(st->regmap, AD74413R_REG_ADC_CONV_CTRL,
486 				  AD74413R_CH_EN_MASK(channel),
487 				  status ? AD74413R_CH_EN_MASK(channel) : 0);
488 }
489 
ad74413r_get_adc_range(struct ad74413r_state * st,unsigned int channel,unsigned int * val)490 static int ad74413r_get_adc_range(struct ad74413r_state *st,
491 				  unsigned int channel,
492 				  unsigned int *val)
493 {
494 	int ret;
495 
496 	ret = regmap_read(st->regmap, AD74413R_REG_ADC_CONFIG_X(channel), val);
497 	if (ret)
498 		return ret;
499 
500 	*val = FIELD_GET(AD74413R_ADC_CONFIG_RANGE_MASK, *val);
501 
502 	return 0;
503 }
504 
ad74413r_get_adc_rejection(struct ad74413r_state * st,unsigned int channel,unsigned int * val)505 static int ad74413r_get_adc_rejection(struct ad74413r_state *st,
506 				      unsigned int channel,
507 				      unsigned int *val)
508 {
509 	int ret;
510 
511 	ret = regmap_read(st->regmap, AD74413R_REG_ADC_CONFIG_X(channel), val);
512 	if (ret)
513 		return ret;
514 
515 	*val = FIELD_GET(AD74413R_ADC_CONFIG_REJECTION_MASK, *val);
516 
517 	return 0;
518 }
519 
ad74413r_set_adc_rejection(struct ad74413r_state * st,unsigned int channel,unsigned int val)520 static int ad74413r_set_adc_rejection(struct ad74413r_state *st,
521 				      unsigned int channel,
522 				      unsigned int val)
523 {
524 	return regmap_update_bits(st->regmap,
525 				  AD74413R_REG_ADC_CONFIG_X(channel),
526 				  AD74413R_ADC_CONFIG_REJECTION_MASK,
527 				  FIELD_PREP(AD74413R_ADC_CONFIG_REJECTION_MASK,
528 					     val));
529 }
530 
ad74413r_rejection_to_rate(struct ad74413r_state * st,unsigned int rej,int * val)531 static int ad74413r_rejection_to_rate(struct ad74413r_state *st,
532 				      unsigned int rej, int *val)
533 {
534 	switch (rej) {
535 	case AD74413R_ADC_REJECTION_50_60:
536 		*val = 20;
537 		return 0;
538 	case AD74413R_ADC_REJECTION_NONE:
539 		*val = 4800;
540 		return 0;
541 	case AD74413R_ADC_REJECTION_50_60_HART:
542 		*val = 10;
543 		return 0;
544 	case AD74413R_ADC_REJECTION_HART:
545 		*val = 1200;
546 		return 0;
547 	default:
548 		dev_err(st->dev, "ADC rejection invalid\n");
549 		return -EINVAL;
550 	}
551 }
552 
ad74413r_rate_to_rejection(struct ad74413r_state * st,int rate,unsigned int * val)553 static int ad74413r_rate_to_rejection(struct ad74413r_state *st,
554 				      int rate, unsigned int *val)
555 {
556 	switch (rate) {
557 	case 20:
558 		*val = AD74413R_ADC_REJECTION_50_60;
559 		return 0;
560 	case 4800:
561 		*val = AD74413R_ADC_REJECTION_NONE;
562 		return 0;
563 	case 10:
564 		*val = AD74413R_ADC_REJECTION_50_60_HART;
565 		return 0;
566 	case 1200:
567 		*val = AD74413R_ADC_REJECTION_HART;
568 		return 0;
569 	default:
570 		dev_err(st->dev, "ADC rate invalid\n");
571 		return -EINVAL;
572 	}
573 }
574 
ad74413r_range_to_voltage_range(struct ad74413r_state * st,unsigned int range,int * val)575 static int ad74413r_range_to_voltage_range(struct ad74413r_state *st,
576 					   unsigned int range, int *val)
577 {
578 	switch (range) {
579 	case AD74413R_ADC_RANGE_10V:
580 		*val = 10000;
581 		return 0;
582 	case AD74413R_ADC_RANGE_2P5V_EXT_POW:
583 	case AD74413R_ADC_RANGE_2P5V_INT_POW:
584 		*val = 2500;
585 		return 0;
586 	case AD74413R_ADC_RANGE_5V_BI_DIR:
587 		*val = 5000;
588 		return 0;
589 	default:
590 		dev_err(st->dev, "ADC range invalid\n");
591 		return -EINVAL;
592 	}
593 }
594 
ad74413r_range_to_voltage_offset(struct ad74413r_state * st,unsigned int range,int * val)595 static int ad74413r_range_to_voltage_offset(struct ad74413r_state *st,
596 					    unsigned int range, int *val)
597 {
598 	switch (range) {
599 	case AD74413R_ADC_RANGE_10V:
600 	case AD74413R_ADC_RANGE_2P5V_EXT_POW:
601 		*val = 0;
602 		return 0;
603 	case AD74413R_ADC_RANGE_2P5V_INT_POW:
604 	case AD74413R_ADC_RANGE_5V_BI_DIR:
605 		*val = -2500;
606 		return 0;
607 	default:
608 		dev_err(st->dev, "ADC range invalid\n");
609 		return -EINVAL;
610 	}
611 }
612 
ad74413r_range_to_voltage_offset_raw(struct ad74413r_state * st,unsigned int range,int * val)613 static int ad74413r_range_to_voltage_offset_raw(struct ad74413r_state *st,
614 						unsigned int range, int *val)
615 {
616 	switch (range) {
617 	case AD74413R_ADC_RANGE_10V:
618 	case AD74413R_ADC_RANGE_2P5V_EXT_POW:
619 		*val = 0;
620 		return 0;
621 	case AD74413R_ADC_RANGE_2P5V_INT_POW:
622 		*val = -((int)AD74413R_ADC_RESULT_MAX);
623 		return 0;
624 	case AD74413R_ADC_RANGE_5V_BI_DIR:
625 		*val = -((int)AD74413R_ADC_RESULT_MAX / 2);
626 		return 0;
627 	default:
628 		dev_err(st->dev, "ADC range invalid\n");
629 		return -EINVAL;
630 	}
631 }
632 
ad74413r_get_output_voltage_scale(struct ad74413r_state * st,int * val,int * val2)633 static int ad74413r_get_output_voltage_scale(struct ad74413r_state *st,
634 					     int *val, int *val2)
635 {
636 	*val = AD74413R_DAC_VOLTAGE_MAX;
637 	*val2 = AD74413R_DAC_CODE_MAX;
638 
639 	return IIO_VAL_FRACTIONAL;
640 }
641 
ad74413r_get_output_current_scale(struct ad74413r_state * st,int * val,int * val2)642 static int ad74413r_get_output_current_scale(struct ad74413r_state *st,
643 					     int *val, int *val2)
644 {
645 	*val = regulator_get_voltage(st->refin_reg);
646 	*val2 = st->sense_resistor_ohms * AD74413R_DAC_CODE_MAX * 1000;
647 
648 	return IIO_VAL_FRACTIONAL;
649 }
650 
ad74413r_get_input_voltage_scale(struct ad74413r_state * st,unsigned int channel,int * val,int * val2)651 static int ad74413r_get_input_voltage_scale(struct ad74413r_state *st,
652 					    unsigned int channel,
653 					    int *val, int *val2)
654 {
655 	unsigned int range;
656 	int ret;
657 
658 	ret = ad74413r_get_adc_range(st, channel, &range);
659 	if (ret)
660 		return ret;
661 
662 	ret = ad74413r_range_to_voltage_range(st, range, val);
663 	if (ret)
664 		return ret;
665 
666 	*val2 = AD74413R_ADC_RESULT_MAX;
667 
668 	return IIO_VAL_FRACTIONAL;
669 }
670 
ad74413r_get_input_voltage_offset(struct ad74413r_state * st,unsigned int channel,int * val)671 static int ad74413r_get_input_voltage_offset(struct ad74413r_state *st,
672 					     unsigned int channel, int *val)
673 {
674 	unsigned int range;
675 	int ret;
676 
677 	ret = ad74413r_get_adc_range(st, channel, &range);
678 	if (ret)
679 		return ret;
680 
681 	ret = ad74413r_range_to_voltage_offset_raw(st, range, val);
682 	if (ret)
683 		return ret;
684 
685 	return IIO_VAL_INT;
686 }
687 
ad74413r_get_input_current_scale(struct ad74413r_state * st,unsigned int channel,int * val,int * val2)688 static int ad74413r_get_input_current_scale(struct ad74413r_state *st,
689 					    unsigned int channel, int *val,
690 					    int *val2)
691 {
692 	unsigned int range;
693 	int ret;
694 
695 	ret = ad74413r_get_adc_range(st, channel, &range);
696 	if (ret)
697 		return ret;
698 
699 	ret = ad74413r_range_to_voltage_range(st, range, val);
700 	if (ret)
701 		return ret;
702 
703 	*val2 = AD74413R_ADC_RESULT_MAX * st->sense_resistor_ohms;
704 
705 	return IIO_VAL_FRACTIONAL;
706 }
707 
ad74413_get_input_current_offset(struct ad74413r_state * st,unsigned int channel,int * val)708 static int ad74413_get_input_current_offset(struct ad74413r_state *st,
709 					    unsigned int channel, int *val)
710 {
711 	unsigned int range;
712 	int voltage_range;
713 	int voltage_offset;
714 	int ret;
715 
716 	ret = ad74413r_get_adc_range(st, channel, &range);
717 	if (ret)
718 		return ret;
719 
720 	ret = ad74413r_range_to_voltage_range(st, range, &voltage_range);
721 	if (ret)
722 		return ret;
723 
724 	ret = ad74413r_range_to_voltage_offset(st, range, &voltage_offset);
725 	if (ret)
726 		return ret;
727 
728 	*val = voltage_offset * (int)AD74413R_ADC_RESULT_MAX / voltage_range;
729 
730 	return IIO_VAL_INT;
731 }
732 
ad74413r_get_adc_rate(struct ad74413r_state * st,unsigned int channel,int * val)733 static int ad74413r_get_adc_rate(struct ad74413r_state *st,
734 				 unsigned int channel, int *val)
735 {
736 	unsigned int rejection;
737 	int ret;
738 
739 	ret = ad74413r_get_adc_rejection(st, channel, &rejection);
740 	if (ret)
741 		return ret;
742 
743 	ret = ad74413r_rejection_to_rate(st, rejection, val);
744 	if (ret)
745 		return ret;
746 
747 	return IIO_VAL_INT;
748 }
749 
ad74413r_set_adc_rate(struct ad74413r_state * st,unsigned int channel,int val)750 static int ad74413r_set_adc_rate(struct ad74413r_state *st,
751 				 unsigned int channel, int val)
752 {
753 	unsigned int rejection;
754 	int ret;
755 
756 	ret = ad74413r_rate_to_rejection(st, val, &rejection);
757 	if (ret)
758 		return ret;
759 
760 	return ad74413r_set_adc_rejection(st, channel, rejection);
761 }
762 
ad74413r_trigger_handler(int irq,void * p)763 static irqreturn_t ad74413r_trigger_handler(int irq, void *p)
764 {
765 	struct iio_poll_func *pf = p;
766 	struct iio_dev *indio_dev = pf->indio_dev;
767 	struct ad74413r_state *st = iio_priv(indio_dev);
768 	u8 *rx_buf = st->adc_samples_buf.rx_buf;
769 	unsigned int i;
770 	int ret;
771 
772 	ret = spi_sync(st->spi, &st->adc_samples_msg);
773 	if (ret)
774 		goto out;
775 
776 	for (i = 0; i < st->adc_active_channels; i++)
777 		ad74413r_crc_check(st, &rx_buf[i * AD74413R_FRAME_SIZE]);
778 
779 	iio_push_to_buffers_with_timestamp(indio_dev, &st->adc_samples_buf,
780 					   iio_get_time_ns(indio_dev));
781 
782 out:
783 	iio_trigger_notify_done(indio_dev->trig);
784 
785 	return IRQ_HANDLED;
786 }
787 
ad74413r_adc_data_interrupt(int irq,void * data)788 static irqreturn_t ad74413r_adc_data_interrupt(int irq, void *data)
789 {
790 	struct iio_dev *indio_dev = data;
791 	struct ad74413r_state *st = iio_priv(indio_dev);
792 
793 	if (iio_buffer_enabled(indio_dev))
794 		iio_trigger_poll(st->trig);
795 	else
796 		complete(&st->adc_data_completion);
797 
798 	return IRQ_HANDLED;
799 }
800 
_ad74413r_get_single_adc_result(struct ad74413r_state * st,unsigned int channel,int * val)801 static int _ad74413r_get_single_adc_result(struct ad74413r_state *st,
802 					   unsigned int channel, int *val)
803 {
804 	unsigned int uval;
805 	int ret;
806 
807 	reinit_completion(&st->adc_data_completion);
808 
809 	ret = ad74413r_set_adc_channel_enable(st, channel, true);
810 	if (ret)
811 		return ret;
812 
813 	ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_SINGLE);
814 	if (ret)
815 		return ret;
816 
817 	ret = wait_for_completion_timeout(&st->adc_data_completion,
818 					  msecs_to_jiffies(1000));
819 	if (!ret) {
820 		ret = -ETIMEDOUT;
821 		return ret;
822 	}
823 
824 	ret = regmap_read(st->regmap, AD74413R_REG_ADC_RESULT_X(channel),
825 			  &uval);
826 	if (ret)
827 		return ret;
828 
829 	ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
830 	if (ret)
831 		return ret;
832 
833 	ret = ad74413r_set_adc_channel_enable(st, channel, false);
834 	if (ret)
835 		return ret;
836 
837 	*val = uval;
838 
839 	return IIO_VAL_INT;
840 }
841 
ad74413r_get_single_adc_result(struct iio_dev * indio_dev,unsigned int channel,int * val)842 static int ad74413r_get_single_adc_result(struct iio_dev *indio_dev,
843 					  unsigned int channel, int *val)
844 {
845 	struct ad74413r_state *st = iio_priv(indio_dev);
846 	int ret;
847 
848 	ret = iio_device_claim_direct_mode(indio_dev);
849 	if (ret)
850 		return ret;
851 
852 	mutex_lock(&st->lock);
853 	ret = _ad74413r_get_single_adc_result(st, channel, val);
854 	mutex_unlock(&st->lock);
855 
856 	iio_device_release_direct_mode(indio_dev);
857 
858 	return ret;
859 }
860 
ad74413r_adc_to_resistance_result(int adc_result,int * val)861 static void ad74413r_adc_to_resistance_result(int adc_result, int *val)
862 {
863 	if (adc_result == AD74413R_ADC_RESULT_MAX)
864 		adc_result = AD74413R_ADC_RESULT_MAX - 1;
865 
866 	*val = DIV_ROUND_CLOSEST(adc_result * 2100,
867 				 AD74413R_ADC_RESULT_MAX - adc_result);
868 }
869 
ad74413r_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * active_scan_mask)870 static int ad74413r_update_scan_mode(struct iio_dev *indio_dev,
871 				     const unsigned long *active_scan_mask)
872 {
873 	struct ad74413r_state *st = iio_priv(indio_dev);
874 	struct spi_transfer *xfer = st->adc_samples_xfer;
875 	u8 *rx_buf = st->adc_samples_buf.rx_buf;
876 	u8 *tx_buf = st->adc_samples_tx_buf;
877 	unsigned int channel;
878 	int ret = -EINVAL;
879 
880 	mutex_lock(&st->lock);
881 
882 	spi_message_init(&st->adc_samples_msg);
883 	st->adc_active_channels = 0;
884 
885 	for_each_clear_bit(channel, active_scan_mask, AD74413R_CHANNEL_MAX) {
886 		ret = ad74413r_set_adc_channel_enable(st, channel, false);
887 		if (ret)
888 			goto out;
889 	}
890 
891 	if (*active_scan_mask == 0)
892 		goto out;
893 
894 	/*
895 	 * The read select register is used to select which register's value
896 	 * will be sent by the slave on the next SPI frame.
897 	 *
898 	 * Create an SPI message that, on each step, writes to the read select
899 	 * register to select the ADC result of the next enabled channel, and
900 	 * reads the ADC result of the previous enabled channel.
901 	 *
902 	 * Example:
903 	 * W: [WCH1] [WCH2] [WCH2] [WCH3] [    ]
904 	 * R: [    ] [RCH1] [RCH2] [RCH3] [RCH4]
905 	 */
906 
907 	for_each_set_bit(channel, active_scan_mask, AD74413R_CHANNEL_MAX) {
908 		ret = ad74413r_set_adc_channel_enable(st, channel, true);
909 		if (ret)
910 			goto out;
911 
912 		st->adc_active_channels++;
913 
914 		if (xfer == st->adc_samples_xfer)
915 			xfer->rx_buf = NULL;
916 		else
917 			xfer->rx_buf = rx_buf;
918 
919 		xfer->tx_buf = tx_buf;
920 		xfer->len = AD74413R_FRAME_SIZE;
921 		xfer->cs_change = 1;
922 
923 		ad74413r_format_reg_write(AD74413R_REG_READ_SELECT,
924 					  AD74413R_REG_ADC_RESULT_X(channel),
925 					  tx_buf);
926 
927 		spi_message_add_tail(xfer, &st->adc_samples_msg);
928 
929 		tx_buf += AD74413R_FRAME_SIZE;
930 		if (xfer != st->adc_samples_xfer)
931 			rx_buf += AD74413R_FRAME_SIZE;
932 		xfer++;
933 	}
934 
935 	xfer->rx_buf = rx_buf;
936 	xfer->tx_buf = NULL;
937 	xfer->len = AD74413R_FRAME_SIZE;
938 	xfer->cs_change = 0;
939 
940 	spi_message_add_tail(xfer, &st->adc_samples_msg);
941 
942 out:
943 	mutex_unlock(&st->lock);
944 
945 	return ret;
946 }
947 
ad74413r_buffer_postenable(struct iio_dev * indio_dev)948 static int ad74413r_buffer_postenable(struct iio_dev *indio_dev)
949 {
950 	struct ad74413r_state *st = iio_priv(indio_dev);
951 
952 	return ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_CONTINUOUS);
953 }
954 
ad74413r_buffer_predisable(struct iio_dev * indio_dev)955 static int ad74413r_buffer_predisable(struct iio_dev *indio_dev)
956 {
957 	struct ad74413r_state *st = iio_priv(indio_dev);
958 
959 	return ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
960 }
961 
ad74413r_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long info)962 static int ad74413r_read_raw(struct iio_dev *indio_dev,
963 			     struct iio_chan_spec const *chan,
964 			     int *val, int *val2, long info)
965 {
966 	struct ad74413r_state *st = iio_priv(indio_dev);
967 
968 	switch (info) {
969 	case IIO_CHAN_INFO_SCALE:
970 		switch (chan->type) {
971 		case IIO_VOLTAGE:
972 			if (chan->output)
973 				return ad74413r_get_output_voltage_scale(st,
974 					val, val2);
975 			else
976 				return ad74413r_get_input_voltage_scale(st,
977 					chan->channel, val, val2);
978 		case IIO_CURRENT:
979 			if (chan->output)
980 				return ad74413r_get_output_current_scale(st,
981 					val, val2);
982 			else
983 				return ad74413r_get_input_current_scale(st,
984 					chan->channel, val, val2);
985 		default:
986 			return -EINVAL;
987 		}
988 	case IIO_CHAN_INFO_OFFSET:
989 		switch (chan->type) {
990 		case IIO_VOLTAGE:
991 			return ad74413r_get_input_voltage_offset(st,
992 				chan->channel, val);
993 		case IIO_CURRENT:
994 			return ad74413_get_input_current_offset(st,
995 				chan->channel, val);
996 		default:
997 			return -EINVAL;
998 		}
999 	case IIO_CHAN_INFO_RAW:
1000 		if (chan->output)
1001 			return -EINVAL;
1002 
1003 		return ad74413r_get_single_adc_result(indio_dev, chan->channel,
1004 						      val);
1005 	case IIO_CHAN_INFO_PROCESSED: {
1006 		int ret;
1007 
1008 		ret = ad74413r_get_single_adc_result(indio_dev, chan->channel,
1009 						     val);
1010 		if (ret < 0)
1011 			return ret;
1012 
1013 		ad74413r_adc_to_resistance_result(*val, val);
1014 
1015 		return ret;
1016 	}
1017 	case IIO_CHAN_INFO_SAMP_FREQ:
1018 		return ad74413r_get_adc_rate(st, chan->channel, val);
1019 	default:
1020 		return -EINVAL;
1021 	}
1022 }
1023 
ad74413r_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long info)1024 static int ad74413r_write_raw(struct iio_dev *indio_dev,
1025 			      struct iio_chan_spec const *chan,
1026 			      int val, int val2, long info)
1027 {
1028 	struct ad74413r_state *st = iio_priv(indio_dev);
1029 
1030 	switch (info) {
1031 	case IIO_CHAN_INFO_RAW:
1032 		if (!chan->output)
1033 			return -EINVAL;
1034 
1035 		if (val < 0 || val > AD74413R_DAC_CODE_MAX) {
1036 			dev_err(st->dev, "Invalid DAC code\n");
1037 			return -EINVAL;
1038 		}
1039 
1040 		return ad74413r_set_channel_dac_code(st, chan->channel, val);
1041 	case IIO_CHAN_INFO_SAMP_FREQ:
1042 		return ad74413r_set_adc_rate(st, chan->channel, val);
1043 	default:
1044 		return -EINVAL;
1045 	}
1046 }
1047 
ad74413r_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long info)1048 static int ad74413r_read_avail(struct iio_dev *indio_dev,
1049 			       struct iio_chan_spec const *chan,
1050 			       const int **vals, int *type, int *length,
1051 			       long info)
1052 {
1053 	struct ad74413r_state *st = iio_priv(indio_dev);
1054 
1055 	switch (info) {
1056 	case IIO_CHAN_INFO_SAMP_FREQ:
1057 		if (st->chip_info->hart_support) {
1058 			*vals = ad74413r_adc_sampling_rates_hart;
1059 			*length = ARRAY_SIZE(ad74413r_adc_sampling_rates_hart);
1060 		} else {
1061 			*vals = ad74413r_adc_sampling_rates;
1062 			*length = ARRAY_SIZE(ad74413r_adc_sampling_rates);
1063 		}
1064 		*type = IIO_VAL_INT;
1065 		return IIO_AVAIL_LIST;
1066 	default:
1067 		return -EINVAL;
1068 	}
1069 }
1070 
1071 static const struct iio_buffer_setup_ops ad74413r_buffer_ops = {
1072 	.postenable = &ad74413r_buffer_postenable,
1073 	.predisable = &ad74413r_buffer_predisable,
1074 };
1075 
1076 static const struct iio_trigger_ops ad74413r_trigger_ops = {
1077 	.validate_device = iio_trigger_validate_own_device,
1078 };
1079 
1080 static const struct iio_info ad74413r_info = {
1081 	.read_raw = &ad74413r_read_raw,
1082 	.write_raw = &ad74413r_write_raw,
1083 	.read_avail = &ad74413r_read_avail,
1084 	.update_scan_mode = &ad74413r_update_scan_mode,
1085 };
1086 
1087 #define AD74413R_DAC_CHANNEL(_type, extra_mask_separate)		\
1088 	{								\
1089 		.type = (_type),					\
1090 		.indexed = 1,						\
1091 		.output = 1,						\
1092 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)		\
1093 				      | (extra_mask_separate),		\
1094 	}
1095 
1096 #define AD74413R_ADC_CHANNEL(_type, extra_mask_separate)		\
1097 	{								\
1098 		.type = (_type),					\
1099 		.indexed = 1,						\
1100 		.output = 0,						\
1101 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW)		\
1102 				      | BIT(IIO_CHAN_INFO_SAMP_FREQ)	\
1103 				      | (extra_mask_separate),		\
1104 		.info_mask_separate_available =				\
1105 					BIT(IIO_CHAN_INFO_SAMP_FREQ),	\
1106 		.scan_type = {						\
1107 			.sign = 'u',					\
1108 			.realbits = 16,					\
1109 			.storagebits = 32,				\
1110 			.shift = 8,					\
1111 			.endianness = IIO_BE,				\
1112 		},							\
1113 	}
1114 
1115 #define AD74413R_ADC_VOLTAGE_CHANNEL					\
1116 	AD74413R_ADC_CHANNEL(IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE)	\
1117 			     | BIT(IIO_CHAN_INFO_OFFSET))
1118 
1119 #define AD74413R_ADC_CURRENT_CHANNEL					\
1120 	AD74413R_ADC_CHANNEL(IIO_CURRENT,  BIT(IIO_CHAN_INFO_SCALE)	\
1121 			     | BIT(IIO_CHAN_INFO_OFFSET))
1122 
1123 static struct iio_chan_spec ad74413r_voltage_output_channels[] = {
1124 	AD74413R_DAC_CHANNEL(IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE)),
1125 	AD74413R_ADC_CURRENT_CHANNEL,
1126 };
1127 
1128 static struct iio_chan_spec ad74413r_current_output_channels[] = {
1129 	AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
1130 	AD74413R_ADC_VOLTAGE_CHANNEL,
1131 };
1132 
1133 static struct iio_chan_spec ad74413r_voltage_input_channels[] = {
1134 	AD74413R_ADC_VOLTAGE_CHANNEL,
1135 };
1136 
1137 static struct iio_chan_spec ad74413r_current_input_channels[] = {
1138 	AD74413R_ADC_CURRENT_CHANNEL,
1139 };
1140 
1141 static struct iio_chan_spec ad74413r_current_input_loop_channels[] = {
1142 	AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
1143 	AD74413R_ADC_CURRENT_CHANNEL,
1144 };
1145 
1146 static struct iio_chan_spec ad74413r_resistance_input_channels[] = {
1147 	AD74413R_ADC_CHANNEL(IIO_RESISTANCE, BIT(IIO_CHAN_INFO_PROCESSED)),
1148 };
1149 
1150 static struct iio_chan_spec ad74413r_digital_input_channels[] = {
1151 	AD74413R_ADC_VOLTAGE_CHANNEL,
1152 };
1153 
1154 #define _AD74413R_CHANNELS(_channels)			\
1155 	{						\
1156 		.channels = _channels,			\
1157 		.num_channels = ARRAY_SIZE(_channels),	\
1158 	}
1159 
1160 #define AD74413R_CHANNELS(name) \
1161 	_AD74413R_CHANNELS(ad74413r_ ## name ## _channels)
1162 
1163 static const struct ad74413r_channels ad74413r_channels_map[] = {
1164 	[CH_FUNC_HIGH_IMPEDANCE] = AD74413R_CHANNELS(voltage_input),
1165 	[CH_FUNC_VOLTAGE_OUTPUT] = AD74413R_CHANNELS(voltage_output),
1166 	[CH_FUNC_CURRENT_OUTPUT] = AD74413R_CHANNELS(current_output),
1167 	[CH_FUNC_VOLTAGE_INPUT] = AD74413R_CHANNELS(voltage_input),
1168 	[CH_FUNC_CURRENT_INPUT_EXT_POWER] = AD74413R_CHANNELS(current_input),
1169 	[CH_FUNC_CURRENT_INPUT_LOOP_POWER] = AD74413R_CHANNELS(current_input_loop),
1170 	[CH_FUNC_RESISTANCE_INPUT] = AD74413R_CHANNELS(resistance_input),
1171 	[CH_FUNC_DIGITAL_INPUT_LOGIC] = AD74413R_CHANNELS(digital_input),
1172 	[CH_FUNC_DIGITAL_INPUT_LOOP_POWER] = AD74413R_CHANNELS(digital_input),
1173 	[CH_FUNC_CURRENT_INPUT_EXT_POWER_HART] = AD74413R_CHANNELS(current_input),
1174 	[CH_FUNC_CURRENT_INPUT_LOOP_POWER_HART] = AD74413R_CHANNELS(current_input),
1175 };
1176 
ad74413r_parse_channel_config(struct iio_dev * indio_dev,struct fwnode_handle * channel_node)1177 static int ad74413r_parse_channel_config(struct iio_dev *indio_dev,
1178 					 struct fwnode_handle *channel_node)
1179 {
1180 	struct ad74413r_state *st = iio_priv(indio_dev);
1181 	struct ad74413r_channel_config *config;
1182 	u32 index;
1183 	int ret;
1184 
1185 	ret = fwnode_property_read_u32(channel_node, "reg", &index);
1186 	if (ret) {
1187 		dev_err(st->dev, "Failed to read channel reg: %d\n", ret);
1188 		return ret;
1189 	}
1190 
1191 	if (index >= AD74413R_CHANNEL_MAX) {
1192 		dev_err(st->dev, "Channel index %u is too large\n", index);
1193 		return -EINVAL;
1194 	}
1195 
1196 	config = &st->channel_configs[index];
1197 	if (config->initialized) {
1198 		dev_err(st->dev, "Channel %u already initialized\n", index);
1199 		return -EINVAL;
1200 	}
1201 
1202 	config->func = CH_FUNC_HIGH_IMPEDANCE;
1203 	fwnode_property_read_u32(channel_node, "adi,ch-func", &config->func);
1204 
1205 	if (config->func < CH_FUNC_MIN || config->func > CH_FUNC_MAX) {
1206 		dev_err(st->dev, "Invalid channel function %u\n", config->func);
1207 		return -EINVAL;
1208 	}
1209 
1210 	if (!st->chip_info->hart_support &&
1211 	    (config->func == CH_FUNC_CURRENT_INPUT_EXT_POWER_HART ||
1212 	     config->func == CH_FUNC_CURRENT_INPUT_LOOP_POWER_HART)) {
1213 		dev_err(st->dev, "Unsupported HART function %u\n", config->func);
1214 		return -EINVAL;
1215 	}
1216 
1217 	if (config->func == CH_FUNC_DIGITAL_INPUT_LOGIC ||
1218 	    config->func == CH_FUNC_DIGITAL_INPUT_LOOP_POWER)
1219 		st->num_comparator_gpios++;
1220 
1221 	config->gpo_comparator = fwnode_property_read_bool(channel_node,
1222 		"adi,gpo-comparator");
1223 
1224 	fwnode_property_read_u32(channel_node, "drive-strength-microamp",
1225 				 &config->drive_strength);
1226 
1227 	if (!config->gpo_comparator)
1228 		st->num_gpo_gpios++;
1229 
1230 	indio_dev->num_channels += ad74413r_channels_map[config->func].num_channels;
1231 
1232 	config->initialized = true;
1233 
1234 	return 0;
1235 }
1236 
ad74413r_parse_channel_configs(struct iio_dev * indio_dev)1237 static int ad74413r_parse_channel_configs(struct iio_dev *indio_dev)
1238 {
1239 	struct ad74413r_state *st = iio_priv(indio_dev);
1240 	struct fwnode_handle *channel_node = NULL;
1241 	int ret;
1242 
1243 	fwnode_for_each_available_child_node(dev_fwnode(st->dev), channel_node) {
1244 		ret = ad74413r_parse_channel_config(indio_dev, channel_node);
1245 		if (ret)
1246 			goto put_channel_node;
1247 	}
1248 
1249 	return 0;
1250 
1251 put_channel_node:
1252 	fwnode_handle_put(channel_node);
1253 
1254 	return ret;
1255 }
1256 
ad74413r_setup_channels(struct iio_dev * indio_dev)1257 static int ad74413r_setup_channels(struct iio_dev *indio_dev)
1258 {
1259 	struct ad74413r_state *st = iio_priv(indio_dev);
1260 	struct ad74413r_channel_config *config;
1261 	struct iio_chan_spec *channels, *chans;
1262 	unsigned int i, num_chans, chan_i;
1263 	int ret;
1264 
1265 	channels = devm_kcalloc(st->dev, sizeof(*channels),
1266 				indio_dev->num_channels, GFP_KERNEL);
1267 	if (!channels)
1268 		return -ENOMEM;
1269 
1270 	indio_dev->channels = channels;
1271 
1272 	for (i = 0; i < AD74413R_CHANNEL_MAX; i++) {
1273 		config = &st->channel_configs[i];
1274 		chans = ad74413r_channels_map[config->func].channels;
1275 		num_chans = ad74413r_channels_map[config->func].num_channels;
1276 
1277 		memcpy(channels, chans, num_chans * sizeof(*chans));
1278 
1279 		for (chan_i = 0; chan_i < num_chans; chan_i++) {
1280 			struct iio_chan_spec *chan = &channels[chan_i];
1281 
1282 			chan->channel = i;
1283 			if (chan->output)
1284 				chan->scan_index = -1;
1285 			else
1286 				chan->scan_index = i;
1287 		}
1288 
1289 		ret = ad74413r_set_channel_function(st, i, config->func);
1290 		if (ret)
1291 			return ret;
1292 
1293 		channels += num_chans;
1294 	}
1295 
1296 	return 0;
1297 }
1298 
ad74413r_setup_gpios(struct ad74413r_state * st)1299 static int ad74413r_setup_gpios(struct ad74413r_state *st)
1300 {
1301 	struct ad74413r_channel_config *config;
1302 	unsigned int comp_gpio_i = 0;
1303 	unsigned int gpo_gpio_i = 0;
1304 	unsigned int i;
1305 	u8 gpo_config;
1306 	u32 strength;
1307 	int ret;
1308 
1309 	for (i = 0; i < AD74413R_CHANNEL_MAX; i++) {
1310 		config = &st->channel_configs[i];
1311 
1312 		if (config->gpo_comparator) {
1313 			gpo_config = AD74413R_GPO_CONFIG_COMPARATOR;
1314 		} else {
1315 			gpo_config = AD74413R_GPO_CONFIG_LOGIC;
1316 			st->gpo_gpio_offsets[gpo_gpio_i++] = i;
1317 		}
1318 
1319 		if (config->func == CH_FUNC_DIGITAL_INPUT_LOGIC ||
1320 		    config->func == CH_FUNC_DIGITAL_INPUT_LOOP_POWER) {
1321 			st->comp_gpio_offsets[comp_gpio_i++] = i;
1322 
1323 			strength = config->drive_strength;
1324 			ret = ad74413r_set_comp_drive_strength(st, i, strength);
1325 			if (ret)
1326 				return ret;
1327 		}
1328 
1329 		ret = ad74413r_set_gpo_config(st, i, gpo_config);
1330 		if (ret)
1331 			return ret;
1332 	}
1333 
1334 	return 0;
1335 }
1336 
ad74413r_regulator_disable(void * regulator)1337 static void ad74413r_regulator_disable(void *regulator)
1338 {
1339 	regulator_disable(regulator);
1340 }
1341 
ad74413r_probe(struct spi_device * spi)1342 static int ad74413r_probe(struct spi_device *spi)
1343 {
1344 	struct ad74413r_state *st;
1345 	struct iio_dev *indio_dev;
1346 	int ret;
1347 
1348 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
1349 	if (!indio_dev)
1350 		return -ENOMEM;
1351 
1352 	st = iio_priv(indio_dev);
1353 
1354 	st->spi = spi;
1355 	st->dev = &spi->dev;
1356 	st->chip_info = device_get_match_data(&spi->dev);
1357 	if (!st->chip_info) {
1358 		const struct spi_device_id *id = spi_get_device_id(spi);
1359 
1360 		if (id)
1361 			st->chip_info =
1362 				(struct ad74413r_chip_info *)id->driver_data;
1363 		if (!st->chip_info)
1364 			return -EINVAL;
1365 	}
1366 
1367 	mutex_init(&st->lock);
1368 	init_completion(&st->adc_data_completion);
1369 
1370 	st->regmap = devm_regmap_init(st->dev, NULL, st,
1371 				      &ad74413r_regmap_config);
1372 	if (IS_ERR(st->regmap))
1373 		return PTR_ERR(st->regmap);
1374 
1375 	st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset", GPIOD_OUT_LOW);
1376 	if (IS_ERR(st->reset_gpio))
1377 		return PTR_ERR(st->reset_gpio);
1378 
1379 	st->refin_reg = devm_regulator_get(st->dev, "refin");
1380 	if (IS_ERR(st->refin_reg))
1381 		return dev_err_probe(st->dev, PTR_ERR(st->refin_reg),
1382 				     "Failed to get refin regulator\n");
1383 
1384 	ret = regulator_enable(st->refin_reg);
1385 	if (ret)
1386 		return ret;
1387 
1388 	ret = devm_add_action_or_reset(st->dev, ad74413r_regulator_disable,
1389 				       st->refin_reg);
1390 	if (ret)
1391 		return ret;
1392 
1393 	st->sense_resistor_ohms = 100000000;
1394 	device_property_read_u32(st->dev, "shunt-resistor-micro-ohms",
1395 				 &st->sense_resistor_ohms);
1396 	st->sense_resistor_ohms /= 1000000;
1397 
1398 	st->trig = devm_iio_trigger_alloc(st->dev, "%s-dev%d",
1399 					  st->chip_info->name, iio_device_id(indio_dev));
1400 	if (!st->trig)
1401 		return -ENOMEM;
1402 
1403 	st->trig->ops = &ad74413r_trigger_ops;
1404 	iio_trigger_set_drvdata(st->trig, st);
1405 
1406 	ret = devm_iio_trigger_register(st->dev, st->trig);
1407 	if (ret)
1408 		return ret;
1409 
1410 	indio_dev->name = st->chip_info->name;
1411 	indio_dev->modes = INDIO_DIRECT_MODE;
1412 	indio_dev->info = &ad74413r_info;
1413 	indio_dev->trig = iio_trigger_get(st->trig);
1414 
1415 	ret = ad74413r_reset(st);
1416 	if (ret)
1417 		return ret;
1418 
1419 	ret = ad74413r_parse_channel_configs(indio_dev);
1420 	if (ret)
1421 		return ret;
1422 
1423 	ret = ad74413r_setup_channels(indio_dev);
1424 	if (ret)
1425 		return ret;
1426 
1427 	ret = ad74413r_setup_gpios(st);
1428 	if (ret)
1429 		return ret;
1430 
1431 	if (st->num_gpo_gpios) {
1432 		st->gpo_gpiochip.owner = THIS_MODULE;
1433 		st->gpo_gpiochip.label = st->chip_info->name;
1434 		st->gpo_gpiochip.base = -1;
1435 		st->gpo_gpiochip.ngpio = st->num_gpo_gpios;
1436 		st->gpo_gpiochip.parent = st->dev;
1437 		st->gpo_gpiochip.can_sleep = true;
1438 		st->gpo_gpiochip.set = ad74413r_gpio_set;
1439 		st->gpo_gpiochip.set_multiple = ad74413r_gpio_set_multiple;
1440 		st->gpo_gpiochip.set_config = ad74413r_gpio_set_gpo_config;
1441 		st->gpo_gpiochip.get_direction =
1442 			ad74413r_gpio_get_gpo_direction;
1443 
1444 		ret = devm_gpiochip_add_data(st->dev, &st->gpo_gpiochip, st);
1445 		if (ret)
1446 			return ret;
1447 	}
1448 
1449 	if (st->num_comparator_gpios) {
1450 		st->comp_gpiochip.owner = THIS_MODULE;
1451 		st->comp_gpiochip.label = st->chip_info->name;
1452 		st->comp_gpiochip.base = -1;
1453 		st->comp_gpiochip.ngpio = st->num_comparator_gpios;
1454 		st->comp_gpiochip.parent = st->dev;
1455 		st->comp_gpiochip.can_sleep = true;
1456 		st->comp_gpiochip.get = ad74413r_gpio_get;
1457 		st->comp_gpiochip.get_multiple = ad74413r_gpio_get_multiple;
1458 		st->comp_gpiochip.set_config = ad74413r_gpio_set_comp_config;
1459 		st->comp_gpiochip.get_direction =
1460 			ad74413r_gpio_get_comp_direction;
1461 
1462 		ret = devm_gpiochip_add_data(st->dev, &st->comp_gpiochip, st);
1463 		if (ret)
1464 			return ret;
1465 	}
1466 
1467 	ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
1468 	if (ret)
1469 		return ret;
1470 
1471 	ret = devm_request_irq(st->dev, spi->irq, ad74413r_adc_data_interrupt,
1472 			       0, st->chip_info->name, indio_dev);
1473 	if (ret)
1474 		return dev_err_probe(st->dev, ret, "Failed to request irq\n");
1475 
1476 	ret = devm_iio_triggered_buffer_setup(st->dev, indio_dev,
1477 					      &iio_pollfunc_store_time,
1478 					      &ad74413r_trigger_handler,
1479 					      &ad74413r_buffer_ops);
1480 	if (ret)
1481 		return ret;
1482 
1483 	return devm_iio_device_register(st->dev, indio_dev);
1484 }
1485 
ad74413r_unregister_driver(struct spi_driver * spi)1486 static int ad74413r_unregister_driver(struct spi_driver *spi)
1487 {
1488 	spi_unregister_driver(spi);
1489 
1490 	return 0;
1491 }
1492 
ad74413r_register_driver(struct spi_driver * spi)1493 static int __init ad74413r_register_driver(struct spi_driver *spi)
1494 {
1495 	crc8_populate_msb(ad74413r_crc8_table, AD74413R_CRC_POLYNOMIAL);
1496 
1497 	return spi_register_driver(spi);
1498 }
1499 
1500 static const struct ad74413r_chip_info ad74412r_chip_info_data = {
1501 	.hart_support = false,
1502 	.name = "ad74412r",
1503 };
1504 
1505 static const struct ad74413r_chip_info ad74413r_chip_info_data = {
1506 	.hart_support = true,
1507 	.name = "ad74413r",
1508 };
1509 
1510 static const struct of_device_id ad74413r_dt_id[] = {
1511 	{
1512 		.compatible = "adi,ad74412r",
1513 		.data = &ad74412r_chip_info_data,
1514 	},
1515 	{
1516 		.compatible = "adi,ad74413r",
1517 		.data = &ad74413r_chip_info_data,
1518 	},
1519 	{},
1520 };
1521 MODULE_DEVICE_TABLE(of, ad74413r_dt_id);
1522 
1523 static const struct spi_device_id ad74413r_spi_id[] = {
1524 	{ .name = "ad74412r", .driver_data = (kernel_ulong_t)&ad74412r_chip_info_data },
1525 	{ .name = "ad74413r", .driver_data = (kernel_ulong_t)&ad74413r_chip_info_data },
1526 	{}
1527 };
1528 MODULE_DEVICE_TABLE(spi, ad74413r_spi_id);
1529 
1530 static struct spi_driver ad74413r_driver = {
1531 	.driver = {
1532 		   .name = "ad74413r",
1533 		   .of_match_table = ad74413r_dt_id,
1534 	},
1535 	.probe = ad74413r_probe,
1536 	.id_table = ad74413r_spi_id,
1537 };
1538 
1539 module_driver(ad74413r_driver,
1540 	      ad74413r_register_driver,
1541 	      ad74413r_unregister_driver);
1542 
1543 MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>");
1544 MODULE_DESCRIPTION("Analog Devices AD74413R ADDAC");
1545 MODULE_LICENSE("GPL v2");
1546