xref: /linux/drivers/iio/adc/ad4130.c (revision bfb921b2a9d5d1123d1d10b196a39db629ddef87)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2022 Analog Devices, Inc.
4  * Author: Cosmin Tanislav <cosmin.tanislav@analog.com>
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/bitops.h>
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/gpio/driver.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/property.h>
20 #include <linux/regmap.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/spi/spi.h>
23 #include <linux/units.h>
24 
25 #include <asm/div64.h>
26 #include <asm/unaligned.h>
27 
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/iio.h>
30 #include <linux/iio/kfifo_buf.h>
31 #include <linux/iio/sysfs.h>
32 
33 #define AD4130_NAME				"ad4130"
34 
35 #define AD4130_COMMS_READ_MASK			BIT(6)
36 
37 #define AD4130_STATUS_REG			0x00
38 
39 #define AD4130_ADC_CONTROL_REG			0x01
40 #define AD4130_ADC_CONTROL_BIPOLAR_MASK		BIT(14)
41 #define AD4130_ADC_CONTROL_INT_REF_VAL_MASK	BIT(13)
42 #define AD4130_INT_REF_2_5V			2500000
43 #define AD4130_INT_REF_1_25V			1250000
44 #define AD4130_ADC_CONTROL_CSB_EN_MASK		BIT(9)
45 #define AD4130_ADC_CONTROL_INT_REF_EN_MASK	BIT(8)
46 #define AD4130_ADC_CONTROL_MODE_MASK		GENMASK(5, 2)
47 #define AD4130_ADC_CONTROL_MCLK_SEL_MASK	GENMASK(1, 0)
48 #define AD4130_MCLK_FREQ_76_8KHZ		76800
49 #define AD4130_MCLK_FREQ_153_6KHZ		153600
50 
51 #define AD4130_DATA_REG				0x02
52 
53 #define AD4130_IO_CONTROL_REG			0x03
54 #define AD4130_IO_CONTROL_INT_PIN_SEL_MASK	GENMASK(9, 8)
55 #define AD4130_IO_CONTROL_GPIO_DATA_MASK	GENMASK(7, 4)
56 #define AD4130_IO_CONTROL_GPIO_CTRL_MASK	GENMASK(3, 0)
57 
58 #define AD4130_VBIAS_REG			0x04
59 
60 #define AD4130_ID_REG				0x05
61 
62 #define AD4130_ERROR_REG			0x06
63 
64 #define AD4130_ERROR_EN_REG			0x07
65 
66 #define AD4130_MCLK_COUNT_REG			0x08
67 
68 #define AD4130_CHANNEL_X_REG(x)			(0x09 + (x))
69 #define AD4130_CHANNEL_EN_MASK			BIT(23)
70 #define AD4130_CHANNEL_SETUP_MASK		GENMASK(22, 20)
71 #define AD4130_CHANNEL_AINP_MASK		GENMASK(17, 13)
72 #define AD4130_CHANNEL_AINM_MASK		GENMASK(12, 8)
73 #define AD4130_CHANNEL_IOUT1_MASK		GENMASK(7, 4)
74 #define AD4130_CHANNEL_IOUT2_MASK		GENMASK(3, 0)
75 
76 #define AD4130_CONFIG_X_REG(x)			(0x19 + (x))
77 #define AD4130_CONFIG_IOUT1_VAL_MASK		GENMASK(15, 13)
78 #define AD4130_CONFIG_IOUT2_VAL_MASK		GENMASK(12, 10)
79 #define AD4130_CONFIG_BURNOUT_MASK		GENMASK(9, 8)
80 #define AD4130_CONFIG_REF_BUFP_MASK		BIT(7)
81 #define AD4130_CONFIG_REF_BUFM_MASK		BIT(6)
82 #define AD4130_CONFIG_REF_SEL_MASK		GENMASK(5, 4)
83 #define AD4130_CONFIG_PGA_MASK			GENMASK(3, 1)
84 
85 #define AD4130_FILTER_X_REG(x)			(0x21 + (x))
86 #define AD4130_FILTER_MODE_MASK			GENMASK(15, 12)
87 #define AD4130_FILTER_SELECT_MASK		GENMASK(10, 0)
88 #define AD4130_FILTER_SELECT_MIN		1
89 
90 #define AD4130_OFFSET_X_REG(x)			(0x29 + (x))
91 
92 #define AD4130_GAIN_X_REG(x)			(0x31 + (x))
93 
94 #define AD4130_MISC_REG				0x39
95 
96 #define AD4130_FIFO_CONTROL_REG			0x3a
97 #define AD4130_FIFO_CONTROL_HEADER_MASK		BIT(18)
98 #define AD4130_FIFO_CONTROL_MODE_MASK		GENMASK(17, 16)
99 #define AD4130_FIFO_CONTROL_WM_INT_EN_MASK	BIT(9)
100 #define AD4130_FIFO_CONTROL_WM_MASK		GENMASK(7, 0)
101 #define AD4130_WATERMARK_256			0
102 
103 #define AD4130_FIFO_STATUS_REG			0x3b
104 
105 #define AD4130_FIFO_THRESHOLD_REG		0x3c
106 
107 #define AD4130_FIFO_DATA_REG			0x3d
108 #define AD4130_FIFO_SIZE			256
109 #define AD4130_FIFO_MAX_SAMPLE_SIZE		3
110 
111 #define AD4130_MAX_ANALOG_PINS			16
112 #define AD4130_MAX_CHANNELS			16
113 #define AD4130_MAX_DIFF_INPUTS			30
114 #define AD4130_MAX_GPIOS			4
115 #define AD4130_MAX_ODR				2400
116 #define AD4130_MAX_PGA				8
117 #define AD4130_MAX_SETUPS			8
118 
119 #define AD4130_AIN2_P1				0x2
120 #define AD4130_AIN3_P2				0x3
121 
122 #define AD4130_RESET_BUF_SIZE			8
123 #define AD4130_RESET_SLEEP_US			(160 * MICRO / AD4130_MCLK_FREQ_76_8KHZ)
124 
125 #define AD4130_INVALID_SLOT			-1
126 
127 static const unsigned int ad4130_reg_size[] = {
128 	[AD4130_STATUS_REG] = 1,
129 	[AD4130_ADC_CONTROL_REG] = 2,
130 	[AD4130_DATA_REG] = 3,
131 	[AD4130_IO_CONTROL_REG] = 2,
132 	[AD4130_VBIAS_REG] = 2,
133 	[AD4130_ID_REG] = 1,
134 	[AD4130_ERROR_REG] = 2,
135 	[AD4130_ERROR_EN_REG] = 2,
136 	[AD4130_MCLK_COUNT_REG] = 1,
137 	[AD4130_CHANNEL_X_REG(0) ... AD4130_CHANNEL_X_REG(AD4130_MAX_CHANNELS - 1)] = 3,
138 	[AD4130_CONFIG_X_REG(0) ... AD4130_CONFIG_X_REG(AD4130_MAX_SETUPS - 1)] = 2,
139 	[AD4130_FILTER_X_REG(0) ... AD4130_FILTER_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
140 	[AD4130_OFFSET_X_REG(0) ... AD4130_OFFSET_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
141 	[AD4130_GAIN_X_REG(0) ... AD4130_GAIN_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
142 	[AD4130_MISC_REG] = 2,
143 	[AD4130_FIFO_CONTROL_REG] = 3,
144 	[AD4130_FIFO_STATUS_REG] = 1,
145 	[AD4130_FIFO_THRESHOLD_REG] = 3,
146 	[AD4130_FIFO_DATA_REG] = 3,
147 };
148 
149 enum ad4130_int_ref_val {
150 	AD4130_INT_REF_VAL_2_5V,
151 	AD4130_INT_REF_VAL_1_25V,
152 };
153 
154 enum ad4130_mclk_sel {
155 	AD4130_MCLK_76_8KHZ,
156 	AD4130_MCLK_76_8KHZ_OUT,
157 	AD4130_MCLK_76_8KHZ_EXT,
158 	AD4130_MCLK_153_6KHZ_EXT,
159 };
160 
161 enum ad4130_int_pin_sel {
162 	AD4130_INT_PIN_INT,
163 	AD4130_INT_PIN_CLK,
164 	AD4130_INT_PIN_P2,
165 	AD4130_INT_PIN_DOUT,
166 };
167 
168 enum ad4130_iout {
169 	AD4130_IOUT_OFF,
170 	AD4130_IOUT_10000NA,
171 	AD4130_IOUT_20000NA,
172 	AD4130_IOUT_50000NA,
173 	AD4130_IOUT_100000NA,
174 	AD4130_IOUT_150000NA,
175 	AD4130_IOUT_200000NA,
176 	AD4130_IOUT_100NA,
177 	AD4130_IOUT_MAX
178 };
179 
180 enum ad4130_burnout {
181 	AD4130_BURNOUT_OFF,
182 	AD4130_BURNOUT_500NA,
183 	AD4130_BURNOUT_2000NA,
184 	AD4130_BURNOUT_4000NA,
185 	AD4130_BURNOUT_MAX
186 };
187 
188 enum ad4130_ref_sel {
189 	AD4130_REF_REFIN1,
190 	AD4130_REF_REFIN2,
191 	AD4130_REF_REFOUT_AVSS,
192 	AD4130_REF_AVDD_AVSS,
193 	AD4130_REF_SEL_MAX
194 };
195 
196 enum ad4130_fifo_mode {
197 	AD4130_FIFO_MODE_DISABLED = 0b00,
198 	AD4130_FIFO_MODE_WM = 0b01,
199 };
200 
201 enum ad4130_mode {
202 	AD4130_MODE_CONTINUOUS = 0b0000,
203 	AD4130_MODE_IDLE = 0b0100,
204 };
205 
206 enum ad4130_filter_mode {
207 	AD4130_FILTER_SINC4,
208 	AD4130_FILTER_SINC4_SINC1,
209 	AD4130_FILTER_SINC3,
210 	AD4130_FILTER_SINC3_REJ60,
211 	AD4130_FILTER_SINC3_SINC1,
212 	AD4130_FILTER_SINC3_PF1,
213 	AD4130_FILTER_SINC3_PF2,
214 	AD4130_FILTER_SINC3_PF3,
215 	AD4130_FILTER_SINC3_PF4,
216 };
217 
218 enum ad4130_pin_function {
219 	AD4130_PIN_FN_NONE,
220 	AD4130_PIN_FN_SPECIAL = BIT(0),
221 	AD4130_PIN_FN_DIFF = BIT(1),
222 	AD4130_PIN_FN_EXCITATION = BIT(2),
223 	AD4130_PIN_FN_VBIAS = BIT(3),
224 };
225 
226 struct ad4130_setup_info {
227 	unsigned int			iout0_val;
228 	unsigned int			iout1_val;
229 	unsigned int			burnout;
230 	unsigned int			pga;
231 	unsigned int			fs;
232 	u32				ref_sel;
233 	enum ad4130_filter_mode		filter_mode;
234 	bool				ref_bufp;
235 	bool				ref_bufm;
236 };
237 
238 struct ad4130_slot_info {
239 	struct ad4130_setup_info	setup;
240 	unsigned int			enabled_channels;
241 	unsigned int			channels;
242 };
243 
244 struct ad4130_chan_info {
245 	struct ad4130_setup_info	setup;
246 	u32				iout0;
247 	u32				iout1;
248 	int				slot;
249 	bool				enabled;
250 	bool				initialized;
251 };
252 
253 struct ad4130_filter_config {
254 	enum ad4130_filter_mode		filter_mode;
255 	unsigned int			odr_div;
256 	unsigned int			fs_max;
257 	enum iio_available_type		samp_freq_avail_type;
258 	int				samp_freq_avail_len;
259 	int				samp_freq_avail[3][2];
260 };
261 
262 struct ad4130_state {
263 	struct regmap			*regmap;
264 	struct spi_device		*spi;
265 	struct clk			*mclk;
266 	struct regulator_bulk_data	regulators[4];
267 	u32				irq_trigger;
268 	u32				inv_irq_trigger;
269 
270 	/*
271 	 * Synchronize access to members the of driver state, and ensure
272 	 * atomicity of consecutive regmap operations.
273 	 */
274 	struct mutex			lock;
275 	struct completion		completion;
276 
277 	struct iio_chan_spec		chans[AD4130_MAX_CHANNELS];
278 	struct ad4130_chan_info		chans_info[AD4130_MAX_CHANNELS];
279 	struct ad4130_slot_info		slots_info[AD4130_MAX_SETUPS];
280 	enum ad4130_pin_function	pins_fn[AD4130_MAX_ANALOG_PINS];
281 	u32				vbias_pins[AD4130_MAX_ANALOG_PINS];
282 	u32				num_vbias_pins;
283 	int				scale_tbls[AD4130_REF_SEL_MAX][AD4130_MAX_PGA][2];
284 	struct gpio_chip		gc;
285 	struct clk_hw			int_clk_hw;
286 
287 	u32			int_pin_sel;
288 	u32			int_ref_uv;
289 	u32			mclk_sel;
290 	bool			int_ref_en;
291 	bool			bipolar;
292 
293 	unsigned int		num_enabled_channels;
294 	unsigned int		effective_watermark;
295 	unsigned int		watermark;
296 
297 	struct spi_message	fifo_msg;
298 	struct spi_transfer	fifo_xfer[2];
299 
300 	/*
301 	 * DMA (thus cache coherency maintenance) requires any transfer
302 	 * buffers to live in their own cache lines. As the use of these
303 	 * buffers is synchronous, all of the buffers used for DMA in this
304 	 * driver may share a cache line.
305 	 */
306 	u8			reset_buf[AD4130_RESET_BUF_SIZE] __aligned(IIO_DMA_MINALIGN);
307 	u8			reg_write_tx_buf[4];
308 	u8			reg_read_tx_buf[1];
309 	u8			reg_read_rx_buf[3];
310 	u8			fifo_tx_buf[2];
311 	u8			fifo_rx_buf[AD4130_FIFO_SIZE *
312 					    AD4130_FIFO_MAX_SAMPLE_SIZE];
313 };
314 
315 static const char * const ad4130_int_pin_names[] = {
316 	[AD4130_INT_PIN_INT] = "int",
317 	[AD4130_INT_PIN_CLK] = "clk",
318 	[AD4130_INT_PIN_P2] = "p2",
319 	[AD4130_INT_PIN_DOUT] = "dout",
320 };
321 
322 static const unsigned int ad4130_iout_current_na_tbl[AD4130_IOUT_MAX] = {
323 	[AD4130_IOUT_OFF] = 0,
324 	[AD4130_IOUT_100NA] = 100,
325 	[AD4130_IOUT_10000NA] = 10000,
326 	[AD4130_IOUT_20000NA] = 20000,
327 	[AD4130_IOUT_50000NA] = 50000,
328 	[AD4130_IOUT_100000NA] = 100000,
329 	[AD4130_IOUT_150000NA] = 150000,
330 	[AD4130_IOUT_200000NA] = 200000,
331 };
332 
333 static const unsigned int ad4130_burnout_current_na_tbl[AD4130_BURNOUT_MAX] = {
334 	[AD4130_BURNOUT_OFF] = 0,
335 	[AD4130_BURNOUT_500NA] = 500,
336 	[AD4130_BURNOUT_2000NA] = 2000,
337 	[AD4130_BURNOUT_4000NA] = 4000,
338 };
339 
340 #define AD4130_VARIABLE_ODR_CONFIG(_filter_mode, _odr_div, _fs_max)	\
341 {									\
342 		.filter_mode = (_filter_mode),				\
343 		.odr_div = (_odr_div),					\
344 		.fs_max = (_fs_max),					\
345 		.samp_freq_avail_type = IIO_AVAIL_RANGE,		\
346 		.samp_freq_avail = {					\
347 			{ AD4130_MAX_ODR, (_odr_div) * (_fs_max) },	\
348 			{ AD4130_MAX_ODR, (_odr_div) * (_fs_max) },	\
349 			{ AD4130_MAX_ODR, (_odr_div) },			\
350 		},							\
351 }
352 
353 #define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div)			\
354 {									\
355 		.filter_mode = (_filter_mode),				\
356 		.odr_div = (_odr_div),					\
357 		.fs_max = AD4130_FILTER_SELECT_MIN,			\
358 		.samp_freq_avail_type = IIO_AVAIL_LIST,			\
359 		.samp_freq_avail_len = 1,				\
360 		.samp_freq_avail = {					\
361 			{ AD4130_MAX_ODR, (_odr_div) },			\
362 		},							\
363 }
364 
365 static const struct ad4130_filter_config ad4130_filter_configs[] = {
366 	AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4,       1,  10),
367 	AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10),
368 	AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3,       1,  2047),
369 	AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1,  2047),
370 	AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047),
371 	AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1,      92),
372 	AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2,      100),
373 	AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3,      124),
374 	AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4,      148),
375 };
376 
377 static const char * const ad4130_filter_modes_str[] = {
378 	[AD4130_FILTER_SINC4] = "sinc4",
379 	[AD4130_FILTER_SINC4_SINC1] = "sinc4+sinc1",
380 	[AD4130_FILTER_SINC3] = "sinc3",
381 	[AD4130_FILTER_SINC3_REJ60] = "sinc3+rej60",
382 	[AD4130_FILTER_SINC3_SINC1] = "sinc3+sinc1",
383 	[AD4130_FILTER_SINC3_PF1] = "sinc3+pf1",
384 	[AD4130_FILTER_SINC3_PF2] = "sinc3+pf2",
385 	[AD4130_FILTER_SINC3_PF3] = "sinc3+pf3",
386 	[AD4130_FILTER_SINC3_PF4] = "sinc3+pf4",
387 };
388 
389 static int ad4130_get_reg_size(struct ad4130_state *st, unsigned int reg,
390 			       unsigned int *size)
391 {
392 	if (reg >= ARRAY_SIZE(ad4130_reg_size))
393 		return -EINVAL;
394 
395 	*size = ad4130_reg_size[reg];
396 
397 	return 0;
398 }
399 
400 static unsigned int ad4130_data_reg_size(struct ad4130_state *st)
401 {
402 	unsigned int data_reg_size;
403 	int ret;
404 
405 	ret = ad4130_get_reg_size(st, AD4130_DATA_REG, &data_reg_size);
406 	if (ret)
407 		return 0;
408 
409 	return data_reg_size;
410 }
411 
412 static unsigned int ad4130_resolution(struct ad4130_state *st)
413 {
414 	return ad4130_data_reg_size(st) * BITS_PER_BYTE;
415 }
416 
417 static int ad4130_reg_write(void *context, unsigned int reg, unsigned int val)
418 {
419 	struct ad4130_state *st = context;
420 	unsigned int size;
421 	int ret;
422 
423 	ret = ad4130_get_reg_size(st, reg, &size);
424 	if (ret)
425 		return ret;
426 
427 	st->reg_write_tx_buf[0] = reg;
428 
429 	switch (size) {
430 	case 3:
431 		put_unaligned_be24(val, &st->reg_write_tx_buf[1]);
432 		break;
433 	case 2:
434 		put_unaligned_be16(val, &st->reg_write_tx_buf[1]);
435 		break;
436 	case 1:
437 		st->reg_write_tx_buf[1] = val;
438 		break;
439 	default:
440 		return -EINVAL;
441 	}
442 
443 	return spi_write(st->spi, st->reg_write_tx_buf, size + 1);
444 }
445 
446 static int ad4130_reg_read(void *context, unsigned int reg, unsigned int *val)
447 {
448 	struct ad4130_state *st = context;
449 	struct spi_transfer t[] = {
450 		{
451 			.tx_buf = st->reg_read_tx_buf,
452 			.len = sizeof(st->reg_read_tx_buf),
453 		},
454 		{
455 			.rx_buf = st->reg_read_rx_buf,
456 		},
457 	};
458 	unsigned int size;
459 	int ret;
460 
461 	ret = ad4130_get_reg_size(st, reg, &size);
462 	if (ret)
463 		return ret;
464 
465 	st->reg_read_tx_buf[0] = AD4130_COMMS_READ_MASK | reg;
466 	t[1].len = size;
467 
468 	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
469 	if (ret)
470 		return ret;
471 
472 	switch (size) {
473 	case 3:
474 		*val = get_unaligned_be24(st->reg_read_rx_buf);
475 		break;
476 	case 2:
477 		*val = get_unaligned_be16(st->reg_read_rx_buf);
478 		break;
479 	case 1:
480 		*val = st->reg_read_rx_buf[0];
481 		break;
482 	default:
483 		return -EINVAL;
484 	}
485 
486 	return 0;
487 }
488 
489 static const struct regmap_config ad4130_regmap_config = {
490 	.reg_read = ad4130_reg_read,
491 	.reg_write = ad4130_reg_write,
492 };
493 
494 static int ad4130_gpio_init_valid_mask(struct gpio_chip *gc,
495 				       unsigned long *valid_mask,
496 				       unsigned int ngpios)
497 {
498 	struct ad4130_state *st = gpiochip_get_data(gc);
499 	unsigned int i;
500 
501 	/*
502 	 * Output-only GPIO functionality is available on pins AIN2 through
503 	 * AIN5. If these pins are used for anything else, do not expose them.
504 	 */
505 	for (i = 0; i < ngpios; i++) {
506 		unsigned int pin = i + AD4130_AIN2_P1;
507 		bool valid = st->pins_fn[pin] == AD4130_PIN_FN_NONE;
508 
509 		__assign_bit(i, valid_mask, valid);
510 	}
511 
512 	return 0;
513 }
514 
515 static int ad4130_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
516 {
517 	return GPIO_LINE_DIRECTION_OUT;
518 }
519 
520 static void ad4130_gpio_set(struct gpio_chip *gc, unsigned int offset,
521 			    int value)
522 {
523 	struct ad4130_state *st = gpiochip_get_data(gc);
524 	unsigned int mask = FIELD_PREP(AD4130_IO_CONTROL_GPIO_DATA_MASK,
525 				       BIT(offset));
526 
527 	regmap_update_bits(st->regmap, AD4130_IO_CONTROL_REG, mask,
528 			   value ? mask : 0);
529 }
530 
531 static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode)
532 {
533 	return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
534 				  AD4130_ADC_CONTROL_MODE_MASK,
535 				  FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, mode));
536 }
537 
538 static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en)
539 {
540 	return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
541 				  AD4130_FIFO_CONTROL_WM_INT_EN_MASK,
542 				  FIELD_PREP(AD4130_FIFO_CONTROL_WM_INT_EN_MASK, en));
543 }
544 
545 static unsigned int ad4130_watermark_reg_val(unsigned int val)
546 {
547 	if (val == AD4130_FIFO_SIZE)
548 		val = AD4130_WATERMARK_256;
549 
550 	return val;
551 }
552 
553 static int ad4130_set_fifo_mode(struct ad4130_state *st,
554 				enum ad4130_fifo_mode mode)
555 {
556 	return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
557 				  AD4130_FIFO_CONTROL_MODE_MASK,
558 				  FIELD_PREP(AD4130_FIFO_CONTROL_MODE_MASK, mode));
559 }
560 
561 static void ad4130_push_fifo_data(struct iio_dev *indio_dev)
562 {
563 	struct ad4130_state *st = iio_priv(indio_dev);
564 	unsigned int data_reg_size = ad4130_data_reg_size(st);
565 	unsigned int transfer_len = st->effective_watermark * data_reg_size;
566 	unsigned int set_size = st->num_enabled_channels * data_reg_size;
567 	unsigned int i;
568 	int ret;
569 
570 	st->fifo_tx_buf[1] = ad4130_watermark_reg_val(st->effective_watermark);
571 	st->fifo_xfer[1].len = transfer_len;
572 
573 	ret = spi_sync(st->spi, &st->fifo_msg);
574 	if (ret)
575 		return;
576 
577 	for (i = 0; i < transfer_len; i += set_size)
578 		iio_push_to_buffers(indio_dev, &st->fifo_rx_buf[i]);
579 }
580 
581 static irqreturn_t ad4130_irq_handler(int irq, void *private)
582 {
583 	struct iio_dev *indio_dev = private;
584 	struct ad4130_state *st = iio_priv(indio_dev);
585 
586 	if (iio_buffer_enabled(indio_dev))
587 		ad4130_push_fifo_data(indio_dev);
588 	else
589 		complete(&st->completion);
590 
591 	return IRQ_HANDLED;
592 }
593 
594 static int ad4130_find_slot(struct ad4130_state *st,
595 			    struct ad4130_setup_info *target_setup_info,
596 			    unsigned int *slot, bool *overwrite)
597 {
598 	unsigned int i;
599 
600 	*slot = AD4130_INVALID_SLOT;
601 	*overwrite = false;
602 
603 	for (i = 0; i < AD4130_MAX_SETUPS; i++) {
604 		struct ad4130_slot_info *slot_info = &st->slots_info[i];
605 
606 		/* Immediately accept a matching setup info. */
607 		if (!memcmp(target_setup_info, &slot_info->setup,
608 			    sizeof(*target_setup_info))) {
609 			*slot = i;
610 			return 0;
611 		}
612 
613 		/* Ignore all setups which are used by enabled channels. */
614 		if (slot_info->enabled_channels)
615 			continue;
616 
617 		/* Find the least used slot. */
618 		if (*slot == AD4130_INVALID_SLOT ||
619 		    slot_info->channels < st->slots_info[*slot].channels)
620 			*slot = i;
621 	}
622 
623 	if (*slot == AD4130_INVALID_SLOT)
624 		return -EINVAL;
625 
626 	*overwrite = true;
627 
628 	return 0;
629 }
630 
631 static void ad4130_unlink_channel(struct ad4130_state *st, unsigned int channel)
632 {
633 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
634 	struct ad4130_slot_info *slot_info = &st->slots_info[chan_info->slot];
635 
636 	chan_info->slot = AD4130_INVALID_SLOT;
637 	slot_info->channels--;
638 }
639 
640 static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot)
641 {
642 	unsigned int i;
643 
644 	for (i = 0; i < AD4130_MAX_CHANNELS; i++) {
645 		struct ad4130_chan_info *chan_info = &st->chans_info[i];
646 
647 		if (!chan_info->initialized || chan_info->slot != slot)
648 			continue;
649 
650 		ad4130_unlink_channel(st, i);
651 	}
652 
653 	return 0;
654 }
655 
656 static int ad4130_link_channel_slot(struct ad4130_state *st,
657 				    unsigned int channel, unsigned int slot)
658 {
659 	struct ad4130_slot_info *slot_info = &st->slots_info[slot];
660 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
661 	int ret;
662 
663 	ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
664 				 AD4130_CHANNEL_SETUP_MASK,
665 				 FIELD_PREP(AD4130_CHANNEL_SETUP_MASK, slot));
666 	if (ret)
667 		return ret;
668 
669 	chan_info->slot = slot;
670 	slot_info->channels++;
671 
672 	return 0;
673 }
674 
675 static int ad4130_write_slot_setup(struct ad4130_state *st,
676 				   unsigned int slot,
677 				   struct ad4130_setup_info *setup_info)
678 {
679 	unsigned int val;
680 	int ret;
681 
682 	val = FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout0_val) |
683 	      FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout1_val) |
684 	      FIELD_PREP(AD4130_CONFIG_BURNOUT_MASK, setup_info->burnout) |
685 	      FIELD_PREP(AD4130_CONFIG_REF_BUFP_MASK, setup_info->ref_bufp) |
686 	      FIELD_PREP(AD4130_CONFIG_REF_BUFM_MASK, setup_info->ref_bufm) |
687 	      FIELD_PREP(AD4130_CONFIG_REF_SEL_MASK, setup_info->ref_sel) |
688 	      FIELD_PREP(AD4130_CONFIG_PGA_MASK, setup_info->pga);
689 
690 	ret = regmap_write(st->regmap, AD4130_CONFIG_X_REG(slot), val);
691 	if (ret)
692 		return ret;
693 
694 	val = FIELD_PREP(AD4130_FILTER_MODE_MASK, setup_info->filter_mode) |
695 	      FIELD_PREP(AD4130_FILTER_SELECT_MASK, setup_info->fs);
696 
697 	ret = regmap_write(st->regmap, AD4130_FILTER_X_REG(slot), val);
698 	if (ret)
699 		return ret;
700 
701 	memcpy(&st->slots_info[slot].setup, setup_info, sizeof(*setup_info));
702 
703 	return 0;
704 }
705 
706 static int ad4130_write_channel_setup(struct ad4130_state *st,
707 				      unsigned int channel, bool on_enable)
708 {
709 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
710 	struct ad4130_setup_info *setup_info = &chan_info->setup;
711 	bool overwrite;
712 	int slot;
713 	int ret;
714 
715 	/*
716 	 * The following cases need to be handled.
717 	 *
718 	 * 1. Enabled and linked channel with setup changes:
719 	 *    - Find a slot. If not possible, return error.
720 	 *    - Unlink channel from current slot.
721 	 *    - If the slot has channels linked to it, unlink all channels, and
722 	 *      write the new setup to it.
723 	 *    - Link channel to new slot.
724 	 *
725 	 * 2. Soon to be enabled and unlinked channel:
726 	 *    - Find a slot. If not possible, return error.
727 	 *    - If the slot has channels linked to it, unlink all channels, and
728 	 *      write the new setup to it.
729 	 *    - Link channel to the slot.
730 	 *
731 	 * 3. Disabled and linked channel with setup changes:
732 	 *    - Unlink channel from current slot.
733 	 *
734 	 * 4. Soon to be enabled and linked channel:
735 	 * 5. Disabled and unlinked channel with setup changes:
736 	 *    - Do nothing.
737 	 */
738 
739 	/* Case 4 */
740 	if (on_enable && chan_info->slot != AD4130_INVALID_SLOT)
741 		return 0;
742 
743 	if (!on_enable && !chan_info->enabled) {
744 		if (chan_info->slot != AD4130_INVALID_SLOT)
745 			/* Case 3 */
746 			ad4130_unlink_channel(st, channel);
747 
748 		/* Cases 3 & 5 */
749 		return 0;
750 	}
751 
752 	/* Cases 1 & 2 */
753 	ret = ad4130_find_slot(st, setup_info, &slot, &overwrite);
754 	if (ret)
755 		return ret;
756 
757 	if (chan_info->slot != AD4130_INVALID_SLOT)
758 		/* Case 1 */
759 		ad4130_unlink_channel(st, channel);
760 
761 	if (overwrite) {
762 		ret = ad4130_unlink_slot(st, slot);
763 		if (ret)
764 			return ret;
765 
766 		ret = ad4130_write_slot_setup(st, slot, setup_info);
767 		if (ret)
768 			return ret;
769 	}
770 
771 	return ad4130_link_channel_slot(st, channel, slot);
772 }
773 
774 static int ad4130_set_channel_enable(struct ad4130_state *st,
775 				     unsigned int channel, bool status)
776 {
777 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
778 	struct ad4130_slot_info *slot_info;
779 	int ret;
780 
781 	if (chan_info->enabled == status)
782 		return 0;
783 
784 	if (status) {
785 		ret = ad4130_write_channel_setup(st, channel, true);
786 		if (ret)
787 			return ret;
788 	}
789 
790 	slot_info = &st->slots_info[chan_info->slot];
791 
792 	ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
793 				 AD4130_CHANNEL_EN_MASK,
794 				 FIELD_PREP(AD4130_CHANNEL_EN_MASK, status));
795 	if (ret)
796 		return ret;
797 
798 	slot_info->enabled_channels += status ? 1 : -1;
799 	chan_info->enabled = status;
800 
801 	return 0;
802 }
803 
804 /*
805  * Table 58. FILTER_MODE_n bits and Filter Types of the datasheet describes
806  * the relation between filter mode, ODR and FS.
807  *
808  * Notice that the max ODR of each filter mode is not necessarily the
809  * absolute max ODR supported by the chip.
810  *
811  * The ODR divider is not explicitly specified, but it can be deduced based
812  * on the ODR range of each filter mode.
813  *
814  * For example, for Sinc4+Sinc1, max ODR is 218.18. That means that the
815  * absolute max ODR is divided by 11 to achieve the max ODR of this filter
816  * mode.
817  *
818  * The formulas for converting between ODR and FS for a specific filter
819  * mode can be deduced from the same table.
820  *
821  * Notice that FS = 1 actually means max ODR, and that ODR decreases by
822  * (maximum ODR / maximum FS) for each increment of FS.
823  *
824  * odr = MAX_ODR / odr_div * (1 - (fs - 1) / fs_max) <=>
825  * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
826  * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
827  * odr = MAX_ODR * (fs_max - fs + 1) / (fs_max * odr_div)
828  * (used in ad4130_fs_to_freq)
829  *
830  * For the opposite formula, FS can be extracted from the last one.
831  *
832  * MAX_ODR * (fs_max - fs + 1) = fs_max * odr_div * odr <=>
833  * fs_max - fs + 1 = fs_max * odr_div * odr / MAX_ODR <=>
834  * fs = 1 + fs_max - fs_max * odr_div * odr / MAX_ODR
835  * (used in ad4130_fs_to_freq)
836  */
837 
838 static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode,
839 			      int val, int val2, unsigned int *fs)
840 {
841 	const struct ad4130_filter_config *filter_config =
842 		&ad4130_filter_configs[filter_mode];
843 	u64 dividend, divisor;
844 	int temp;
845 
846 	dividend = filter_config->fs_max * filter_config->odr_div *
847 		   ((u64)val * NANO + val2);
848 	divisor = (u64)AD4130_MAX_ODR * NANO;
849 
850 	temp = AD4130_FILTER_SELECT_MIN + filter_config->fs_max -
851 	       DIV64_U64_ROUND_CLOSEST(dividend, divisor);
852 
853 	if (temp < AD4130_FILTER_SELECT_MIN)
854 		temp = AD4130_FILTER_SELECT_MIN;
855 	else if (temp > filter_config->fs_max)
856 		temp = filter_config->fs_max;
857 
858 	*fs = temp;
859 }
860 
861 static void ad4130_fs_to_freq(enum ad4130_filter_mode filter_mode,
862 			      unsigned int fs, int *val, int *val2)
863 {
864 	const struct ad4130_filter_config *filter_config =
865 		&ad4130_filter_configs[filter_mode];
866 	unsigned int dividend, divisor;
867 	u64 temp;
868 
869 	dividend = (filter_config->fs_max - fs + AD4130_FILTER_SELECT_MIN) *
870 		   AD4130_MAX_ODR;
871 	divisor = filter_config->fs_max * filter_config->odr_div;
872 
873 	temp = div_u64((u64)dividend * NANO, divisor);
874 	*val = div_u64_rem(temp, NANO, val2);
875 }
876 
877 static int ad4130_set_filter_mode(struct iio_dev *indio_dev,
878 				  const struct iio_chan_spec *chan,
879 				  unsigned int val)
880 {
881 	struct ad4130_state *st = iio_priv(indio_dev);
882 	unsigned int channel = chan->scan_index;
883 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
884 	struct ad4130_setup_info *setup_info = &chan_info->setup;
885 	enum ad4130_filter_mode old_filter_mode;
886 	int freq_val, freq_val2;
887 	unsigned int old_fs;
888 	int ret = 0;
889 
890 	guard(mutex)(&st->lock);
891 	if (setup_info->filter_mode == val)
892 		return 0;
893 
894 	old_fs = setup_info->fs;
895 	old_filter_mode = setup_info->filter_mode;
896 
897 	/*
898 	 * When switching between filter modes, try to match the ODR as
899 	 * close as possible. To do this, convert the current FS into ODR
900 	 * using the old filter mode, then convert it back into FS using
901 	 * the new filter mode.
902 	 */
903 	ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
904 			  &freq_val, &freq_val2);
905 
906 	ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs);
907 
908 	setup_info->filter_mode = val;
909 
910 	ret = ad4130_write_channel_setup(st, channel, false);
911 	if (ret) {
912 		setup_info->fs = old_fs;
913 		setup_info->filter_mode = old_filter_mode;
914 		return ret;
915 	}
916 
917 	return 0;
918 }
919 
920 static int ad4130_get_filter_mode(struct iio_dev *indio_dev,
921 				  const struct iio_chan_spec *chan)
922 {
923 	struct ad4130_state *st = iio_priv(indio_dev);
924 	unsigned int channel = chan->scan_index;
925 	struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
926 	enum ad4130_filter_mode filter_mode;
927 
928 	guard(mutex)(&st->lock);
929 	filter_mode = setup_info->filter_mode;
930 
931 	return filter_mode;
932 }
933 
934 static const struct iio_enum ad4130_filter_mode_enum = {
935 	.items = ad4130_filter_modes_str,
936 	.num_items = ARRAY_SIZE(ad4130_filter_modes_str),
937 	.set = ad4130_set_filter_mode,
938 	.get = ad4130_get_filter_mode,
939 };
940 
941 static const struct iio_chan_spec_ext_info ad4130_filter_mode_ext_info[] = {
942 	IIO_ENUM("filter_mode", IIO_SEPARATE, &ad4130_filter_mode_enum),
943 	IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_TYPE,
944 			   &ad4130_filter_mode_enum),
945 	{ }
946 };
947 
948 static const struct iio_chan_spec ad4130_channel_template = {
949 	.type = IIO_VOLTAGE,
950 	.indexed = 1,
951 	.differential = 1,
952 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
953 			      BIT(IIO_CHAN_INFO_SCALE) |
954 			      BIT(IIO_CHAN_INFO_OFFSET) |
955 			      BIT(IIO_CHAN_INFO_SAMP_FREQ),
956 	.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) |
957 					BIT(IIO_CHAN_INFO_SAMP_FREQ),
958 	.ext_info = ad4130_filter_mode_ext_info,
959 	.scan_type = {
960 		.sign = 'u',
961 		.endianness = IIO_BE,
962 	},
963 };
964 
965 static int ad4130_set_channel_pga(struct ad4130_state *st, unsigned int channel,
966 				  int val, int val2)
967 {
968 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
969 	struct ad4130_setup_info *setup_info = &chan_info->setup;
970 	unsigned int pga, old_pga;
971 	int ret;
972 
973 	for (pga = 0; pga < AD4130_MAX_PGA; pga++)
974 		if (val == st->scale_tbls[setup_info->ref_sel][pga][0] &&
975 		    val2 == st->scale_tbls[setup_info->ref_sel][pga][1])
976 			break;
977 
978 	if (pga == AD4130_MAX_PGA)
979 		return -EINVAL;
980 
981 	guard(mutex)(&st->lock);
982 	if (pga == setup_info->pga)
983 		return 0;
984 
985 	old_pga = setup_info->pga;
986 	setup_info->pga = pga;
987 
988 	ret = ad4130_write_channel_setup(st, channel, false);
989 	if (ret) {
990 		setup_info->pga = old_pga;
991 		return ret;
992 	}
993 
994 	return 0;
995 }
996 
997 static int ad4130_set_channel_freq(struct ad4130_state *st,
998 				   unsigned int channel, int val, int val2)
999 {
1000 	struct ad4130_chan_info *chan_info = &st->chans_info[channel];
1001 	struct ad4130_setup_info *setup_info = &chan_info->setup;
1002 	unsigned int fs, old_fs;
1003 	int ret;
1004 
1005 	guard(mutex)(&st->lock);
1006 	old_fs = setup_info->fs;
1007 
1008 	ad4130_freq_to_fs(setup_info->filter_mode, val, val2, &fs);
1009 
1010 	if (fs == setup_info->fs)
1011 		return 0;
1012 
1013 	setup_info->fs = fs;
1014 
1015 	ret = ad4130_write_channel_setup(st, channel, false);
1016 	if (ret) {
1017 		setup_info->fs = old_fs;
1018 		return ret;
1019 	}
1020 
1021 	return 0;
1022 }
1023 
1024 static int _ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
1025 			       int *val)
1026 {
1027 	struct ad4130_state *st = iio_priv(indio_dev);
1028 	int ret;
1029 
1030 	ret = ad4130_set_channel_enable(st, channel, true);
1031 	if (ret)
1032 		return ret;
1033 
1034 	reinit_completion(&st->completion);
1035 
1036 	ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
1037 	if (ret)
1038 		return ret;
1039 
1040 	ret = wait_for_completion_timeout(&st->completion,
1041 					  msecs_to_jiffies(1000));
1042 	if (!ret)
1043 		return -ETIMEDOUT;
1044 
1045 	ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
1046 	if (ret)
1047 		return ret;
1048 
1049 	ret = regmap_read(st->regmap, AD4130_DATA_REG, val);
1050 	if (ret)
1051 		return ret;
1052 
1053 	ret = ad4130_set_channel_enable(st, channel, false);
1054 	if (ret)
1055 		return ret;
1056 
1057 	return IIO_VAL_INT;
1058 }
1059 
1060 static int ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
1061 			      int *val)
1062 {
1063 	iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
1064 		struct ad4130_state *st = iio_priv(indio_dev);
1065 
1066 		guard(mutex)(&st->lock);
1067 		return _ad4130_read_sample(indio_dev, channel, val);
1068 	}
1069 	unreachable();
1070 }
1071 
1072 static int ad4130_read_raw(struct iio_dev *indio_dev,
1073 			   struct iio_chan_spec const *chan,
1074 			   int *val, int *val2, long info)
1075 {
1076 	struct ad4130_state *st = iio_priv(indio_dev);
1077 	unsigned int channel = chan->scan_index;
1078 	struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
1079 
1080 	switch (info) {
1081 	case IIO_CHAN_INFO_RAW:
1082 		return ad4130_read_sample(indio_dev, channel, val);
1083 	case IIO_CHAN_INFO_SCALE: {
1084 		guard(mutex)(&st->lock);
1085 		*val = st->scale_tbls[setup_info->ref_sel][setup_info->pga][0];
1086 		*val2 = st->scale_tbls[setup_info->ref_sel][setup_info->pga][1];
1087 
1088 		return IIO_VAL_INT_PLUS_NANO;
1089 	}
1090 	case IIO_CHAN_INFO_OFFSET:
1091 		*val = st->bipolar ? -BIT(chan->scan_type.realbits - 1) : 0;
1092 
1093 		return IIO_VAL_INT;
1094 	case IIO_CHAN_INFO_SAMP_FREQ: {
1095 		guard(mutex)(&st->lock);
1096 		ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
1097 				  val, val2);
1098 
1099 		return IIO_VAL_INT_PLUS_NANO;
1100 	}
1101 	default:
1102 		return -EINVAL;
1103 	}
1104 }
1105 
1106 static int ad4130_read_avail(struct iio_dev *indio_dev,
1107 			     struct iio_chan_spec const *chan,
1108 			     const int **vals, int *type, int *length,
1109 			     long info)
1110 {
1111 	struct ad4130_state *st = iio_priv(indio_dev);
1112 	unsigned int channel = chan->scan_index;
1113 	struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
1114 	const struct ad4130_filter_config *filter_config;
1115 
1116 	switch (info) {
1117 	case IIO_CHAN_INFO_SCALE:
1118 		*vals = (int *)st->scale_tbls[setup_info->ref_sel];
1119 		*length = ARRAY_SIZE(st->scale_tbls[setup_info->ref_sel]) * 2;
1120 
1121 		*type = IIO_VAL_INT_PLUS_NANO;
1122 
1123 		return IIO_AVAIL_LIST;
1124 	case IIO_CHAN_INFO_SAMP_FREQ:
1125 		scoped_guard(mutex, &st->lock) {
1126 			filter_config = &ad4130_filter_configs[setup_info->filter_mode];
1127 		}
1128 
1129 		*vals = (int *)filter_config->samp_freq_avail;
1130 		*length = filter_config->samp_freq_avail_len * 2;
1131 		*type = IIO_VAL_FRACTIONAL;
1132 
1133 		return filter_config->samp_freq_avail_type;
1134 	default:
1135 		return -EINVAL;
1136 	}
1137 }
1138 
1139 static int ad4130_write_raw_get_fmt(struct iio_dev *indio_dev,
1140 				    struct iio_chan_spec const *chan,
1141 				    long info)
1142 {
1143 	switch (info) {
1144 	case IIO_CHAN_INFO_SCALE:
1145 	case IIO_CHAN_INFO_SAMP_FREQ:
1146 		return IIO_VAL_INT_PLUS_NANO;
1147 	default:
1148 		return -EINVAL;
1149 	}
1150 }
1151 
1152 static int ad4130_write_raw(struct iio_dev *indio_dev,
1153 			    struct iio_chan_spec const *chan,
1154 			    int val, int val2, long info)
1155 {
1156 	struct ad4130_state *st = iio_priv(indio_dev);
1157 	unsigned int channel = chan->scan_index;
1158 
1159 	switch (info) {
1160 	case IIO_CHAN_INFO_SCALE:
1161 		return ad4130_set_channel_pga(st, channel, val, val2);
1162 	case IIO_CHAN_INFO_SAMP_FREQ:
1163 		return ad4130_set_channel_freq(st, channel, val, val2);
1164 	default:
1165 		return -EINVAL;
1166 	}
1167 }
1168 
1169 static int ad4130_reg_access(struct iio_dev *indio_dev, unsigned int reg,
1170 			     unsigned int writeval, unsigned int *readval)
1171 {
1172 	struct ad4130_state *st = iio_priv(indio_dev);
1173 
1174 	if (readval)
1175 		return regmap_read(st->regmap, reg, readval);
1176 
1177 	return regmap_write(st->regmap, reg, writeval);
1178 }
1179 
1180 static int ad4130_update_scan_mode(struct iio_dev *indio_dev,
1181 				   const unsigned long *scan_mask)
1182 {
1183 	struct ad4130_state *st = iio_priv(indio_dev);
1184 	unsigned int channel;
1185 	unsigned int val = 0;
1186 	int ret;
1187 
1188 	guard(mutex)(&st->lock);
1189 
1190 	for_each_set_bit(channel, scan_mask, indio_dev->num_channels) {
1191 		ret = ad4130_set_channel_enable(st, channel, true);
1192 		if (ret)
1193 			return ret;
1194 
1195 		val++;
1196 	}
1197 
1198 	st->num_enabled_channels = val;
1199 
1200 	return 0;
1201 }
1202 
1203 static int ad4130_set_fifo_watermark(struct iio_dev *indio_dev, unsigned int val)
1204 {
1205 	struct ad4130_state *st = iio_priv(indio_dev);
1206 	unsigned int eff;
1207 	int ret;
1208 
1209 	if (val > AD4130_FIFO_SIZE)
1210 		return -EINVAL;
1211 
1212 	eff = val * st->num_enabled_channels;
1213 	if (eff > AD4130_FIFO_SIZE)
1214 		/*
1215 		 * Always set watermark to a multiple of the number of
1216 		 * enabled channels to avoid making the FIFO unaligned.
1217 		 */
1218 		eff = rounddown(AD4130_FIFO_SIZE, st->num_enabled_channels);
1219 
1220 	guard(mutex)(&st->lock);
1221 
1222 	ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
1223 				 AD4130_FIFO_CONTROL_WM_MASK,
1224 				 FIELD_PREP(AD4130_FIFO_CONTROL_WM_MASK,
1225 					    ad4130_watermark_reg_val(eff)));
1226 	if (ret)
1227 		return ret;
1228 
1229 	st->effective_watermark = eff;
1230 	st->watermark = val;
1231 
1232 	return 0;
1233 }
1234 
1235 static const struct iio_info ad4130_info = {
1236 	.read_raw = ad4130_read_raw,
1237 	.read_avail = ad4130_read_avail,
1238 	.write_raw_get_fmt = ad4130_write_raw_get_fmt,
1239 	.write_raw = ad4130_write_raw,
1240 	.update_scan_mode = ad4130_update_scan_mode,
1241 	.hwfifo_set_watermark = ad4130_set_fifo_watermark,
1242 	.debugfs_reg_access = ad4130_reg_access,
1243 };
1244 
1245 static int ad4130_buffer_postenable(struct iio_dev *indio_dev)
1246 {
1247 	struct ad4130_state *st = iio_priv(indio_dev);
1248 	int ret;
1249 
1250 	guard(mutex)(&st->lock);
1251 
1252 	ret = ad4130_set_watermark_interrupt_en(st, true);
1253 	if (ret)
1254 		return ret;
1255 
1256 	ret = irq_set_irq_type(st->spi->irq, st->inv_irq_trigger);
1257 	if (ret)
1258 		return ret;
1259 
1260 	ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_WM);
1261 	if (ret)
1262 		return ret;
1263 
1264 	return ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
1265 }
1266 
1267 static int ad4130_buffer_predisable(struct iio_dev *indio_dev)
1268 {
1269 	struct ad4130_state *st = iio_priv(indio_dev);
1270 	unsigned int i;
1271 	int ret;
1272 
1273 	guard(mutex)(&st->lock);
1274 
1275 	ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
1276 	if (ret)
1277 		return ret;
1278 
1279 	ret = irq_set_irq_type(st->spi->irq, st->irq_trigger);
1280 	if (ret)
1281 		return ret;
1282 
1283 	ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_DISABLED);
1284 	if (ret)
1285 		return ret;
1286 
1287 	ret = ad4130_set_watermark_interrupt_en(st, false);
1288 	if (ret)
1289 		return ret;
1290 
1291 	/*
1292 	 * update_scan_mode() is not called in the disable path, disable all
1293 	 * channels here.
1294 	 */
1295 	for (i = 0; i < indio_dev->num_channels; i++) {
1296 		ret = ad4130_set_channel_enable(st, i, false);
1297 		if (ret)
1298 			return ret;
1299 	}
1300 
1301 	return 0;
1302 }
1303 
1304 static const struct iio_buffer_setup_ops ad4130_buffer_ops = {
1305 	.postenable = ad4130_buffer_postenable,
1306 	.predisable = ad4130_buffer_predisable,
1307 };
1308 
1309 static ssize_t hwfifo_watermark_show(struct device *dev,
1310 				     struct device_attribute *attr, char *buf)
1311 {
1312 	struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
1313 	unsigned int val;
1314 
1315 	guard(mutex)(&st->lock);
1316 	val = st->watermark;
1317 
1318 	return sysfs_emit(buf, "%d\n", val);
1319 }
1320 
1321 static ssize_t hwfifo_enabled_show(struct device *dev,
1322 				   struct device_attribute *attr, char *buf)
1323 {
1324 	struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
1325 	unsigned int val;
1326 	int ret;
1327 
1328 	ret = regmap_read(st->regmap, AD4130_FIFO_CONTROL_REG, &val);
1329 	if (ret)
1330 		return ret;
1331 
1332 	val = FIELD_GET(AD4130_FIFO_CONTROL_MODE_MASK, val);
1333 
1334 	return sysfs_emit(buf, "%d\n", val != AD4130_FIFO_MODE_DISABLED);
1335 }
1336 
1337 static ssize_t hwfifo_watermark_min_show(struct device *dev,
1338 					 struct device_attribute *attr,
1339 					 char *buf)
1340 {
1341 	return sysfs_emit(buf, "%s\n", "1");
1342 }
1343 
1344 static ssize_t hwfifo_watermark_max_show(struct device *dev,
1345 					 struct device_attribute *attr,
1346 					 char *buf)
1347 {
1348 	return sysfs_emit(buf, "%s\n", __stringify(AD4130_FIFO_SIZE));
1349 }
1350 
1351 static IIO_DEVICE_ATTR_RO(hwfifo_watermark_min, 0);
1352 static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0);
1353 static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0);
1354 static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0);
1355 
1356 static const struct iio_dev_attr *ad4130_fifo_attributes[] = {
1357 	&iio_dev_attr_hwfifo_watermark_min,
1358 	&iio_dev_attr_hwfifo_watermark_max,
1359 	&iio_dev_attr_hwfifo_watermark,
1360 	&iio_dev_attr_hwfifo_enabled,
1361 	NULL
1362 };
1363 
1364 static int _ad4130_find_table_index(const unsigned int *tbl, size_t len,
1365 				    unsigned int val)
1366 {
1367 	unsigned int i;
1368 
1369 	for (i = 0; i < len; i++)
1370 		if (tbl[i] == val)
1371 			return i;
1372 
1373 	return -EINVAL;
1374 }
1375 
1376 #define ad4130_find_table_index(table, val) \
1377 	_ad4130_find_table_index(table, ARRAY_SIZE(table), val)
1378 
1379 static int ad4130_get_ref_voltage(struct ad4130_state *st,
1380 				  enum ad4130_ref_sel ref_sel)
1381 {
1382 	switch (ref_sel) {
1383 	case AD4130_REF_REFIN1:
1384 		return regulator_get_voltage(st->regulators[2].consumer);
1385 	case AD4130_REF_REFIN2:
1386 		return regulator_get_voltage(st->regulators[3].consumer);
1387 	case AD4130_REF_AVDD_AVSS:
1388 		return regulator_get_voltage(st->regulators[0].consumer);
1389 	case AD4130_REF_REFOUT_AVSS:
1390 		return st->int_ref_uv;
1391 	default:
1392 		return -EINVAL;
1393 	}
1394 }
1395 
1396 static int ad4130_parse_fw_setup(struct ad4130_state *st,
1397 				 struct fwnode_handle *child,
1398 				 struct ad4130_setup_info *setup_info)
1399 {
1400 	struct device *dev = &st->spi->dev;
1401 	u32 tmp;
1402 	int ret;
1403 
1404 	tmp = 0;
1405 	fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamp", &tmp);
1406 	ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
1407 	if (ret < 0)
1408 		return dev_err_probe(dev, ret,
1409 				     "Invalid excitation current %unA\n", tmp);
1410 	setup_info->iout0_val = ret;
1411 
1412 	tmp = 0;
1413 	fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamp", &tmp);
1414 	ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
1415 	if (ret < 0)
1416 		return dev_err_probe(dev, ret,
1417 				     "Invalid excitation current %unA\n", tmp);
1418 	setup_info->iout1_val = ret;
1419 
1420 	tmp = 0;
1421 	fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp);
1422 	ret = ad4130_find_table_index(ad4130_burnout_current_na_tbl, tmp);
1423 	if (ret < 0)
1424 		return dev_err_probe(dev, ret,
1425 				     "Invalid burnout current %unA\n", tmp);
1426 	setup_info->burnout = ret;
1427 
1428 	setup_info->ref_bufp = fwnode_property_read_bool(child, "adi,buffered-positive");
1429 	setup_info->ref_bufm = fwnode_property_read_bool(child, "adi,buffered-negative");
1430 
1431 	setup_info->ref_sel = AD4130_REF_REFIN1;
1432 	fwnode_property_read_u32(child, "adi,reference-select",
1433 				 &setup_info->ref_sel);
1434 	if (setup_info->ref_sel >= AD4130_REF_SEL_MAX)
1435 		return dev_err_probe(dev, -EINVAL,
1436 				     "Invalid reference selected %u\n",
1437 				     setup_info->ref_sel);
1438 
1439 	if (setup_info->ref_sel == AD4130_REF_REFOUT_AVSS)
1440 		st->int_ref_en = true;
1441 
1442 	ret = ad4130_get_ref_voltage(st, setup_info->ref_sel);
1443 	if (ret < 0)
1444 		return dev_err_probe(dev, ret, "Cannot use reference %u\n",
1445 				     setup_info->ref_sel);
1446 
1447 	return 0;
1448 }
1449 
1450 static int ad4130_validate_diff_channel(struct ad4130_state *st, u32 pin)
1451 {
1452 	struct device *dev = &st->spi->dev;
1453 
1454 	if (pin >= AD4130_MAX_DIFF_INPUTS)
1455 		return dev_err_probe(dev, -EINVAL,
1456 				     "Invalid differential channel %u\n", pin);
1457 
1458 	if (pin >= AD4130_MAX_ANALOG_PINS)
1459 		return 0;
1460 
1461 	if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1462 		return dev_err_probe(dev, -EINVAL,
1463 				     "Pin %u already used with fn %u\n", pin,
1464 				     st->pins_fn[pin]);
1465 
1466 	st->pins_fn[pin] |= AD4130_PIN_FN_DIFF;
1467 
1468 	return 0;
1469 }
1470 
1471 static int ad4130_validate_diff_channels(struct ad4130_state *st,
1472 					 u32 *pins, unsigned int len)
1473 {
1474 	unsigned int i;
1475 	int ret;
1476 
1477 	for (i = 0; i < len; i++) {
1478 		ret = ad4130_validate_diff_channel(st, pins[i]);
1479 		if (ret)
1480 			return ret;
1481 	}
1482 
1483 	return 0;
1484 }
1485 
1486 static int ad4130_validate_excitation_pin(struct ad4130_state *st, u32 pin)
1487 {
1488 	struct device *dev = &st->spi->dev;
1489 
1490 	if (pin >= AD4130_MAX_ANALOG_PINS)
1491 		return dev_err_probe(dev, -EINVAL,
1492 				     "Invalid excitation pin %u\n", pin);
1493 
1494 	if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1495 		return dev_err_probe(dev, -EINVAL,
1496 				     "Pin %u already used with fn %u\n", pin,
1497 				     st->pins_fn[pin]);
1498 
1499 	st->pins_fn[pin] |= AD4130_PIN_FN_EXCITATION;
1500 
1501 	return 0;
1502 }
1503 
1504 static int ad4130_validate_vbias_pin(struct ad4130_state *st, u32 pin)
1505 {
1506 	struct device *dev = &st->spi->dev;
1507 
1508 	if (pin >= AD4130_MAX_ANALOG_PINS)
1509 		return dev_err_probe(dev, -EINVAL, "Invalid vbias pin %u\n",
1510 				     pin);
1511 
1512 	if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1513 		return dev_err_probe(dev, -EINVAL,
1514 				     "Pin %u already used with fn %u\n", pin,
1515 				     st->pins_fn[pin]);
1516 
1517 	st->pins_fn[pin] |= AD4130_PIN_FN_VBIAS;
1518 
1519 	return 0;
1520 }
1521 
1522 static int ad4130_validate_vbias_pins(struct ad4130_state *st,
1523 				      u32 *pins, unsigned int len)
1524 {
1525 	unsigned int i;
1526 	int ret;
1527 
1528 	for (i = 0; i < st->num_vbias_pins; i++) {
1529 		ret = ad4130_validate_vbias_pin(st, pins[i]);
1530 		if (ret)
1531 			return ret;
1532 	}
1533 
1534 	return 0;
1535 }
1536 
1537 static int ad4130_parse_fw_channel(struct iio_dev *indio_dev,
1538 				   struct fwnode_handle *child)
1539 {
1540 	struct ad4130_state *st = iio_priv(indio_dev);
1541 	unsigned int resolution = ad4130_resolution(st);
1542 	unsigned int index = indio_dev->num_channels++;
1543 	struct device *dev = &st->spi->dev;
1544 	struct ad4130_chan_info *chan_info;
1545 	struct iio_chan_spec *chan;
1546 	u32 pins[2];
1547 	int ret;
1548 
1549 	if (index >= AD4130_MAX_CHANNELS)
1550 		return dev_err_probe(dev, -EINVAL, "Too many channels\n");
1551 
1552 	chan = &st->chans[index];
1553 	chan_info = &st->chans_info[index];
1554 
1555 	*chan = ad4130_channel_template;
1556 	chan->scan_type.realbits = resolution;
1557 	chan->scan_type.storagebits = resolution;
1558 	chan->scan_index = index;
1559 
1560 	chan_info->slot = AD4130_INVALID_SLOT;
1561 	chan_info->setup.fs = AD4130_FILTER_SELECT_MIN;
1562 	chan_info->initialized = true;
1563 
1564 	ret = fwnode_property_read_u32_array(child, "diff-channels", pins,
1565 					     ARRAY_SIZE(pins));
1566 	if (ret)
1567 		return ret;
1568 
1569 	ret = ad4130_validate_diff_channels(st, pins, ARRAY_SIZE(pins));
1570 	if (ret)
1571 		return ret;
1572 
1573 	chan->channel = pins[0];
1574 	chan->channel2 = pins[1];
1575 
1576 	ret = ad4130_parse_fw_setup(st, child, &chan_info->setup);
1577 	if (ret)
1578 		return ret;
1579 
1580 	fwnode_property_read_u32(child, "adi,excitation-pin-0",
1581 				 &chan_info->iout0);
1582 	if (chan_info->setup.iout0_val != AD4130_IOUT_OFF) {
1583 		ret = ad4130_validate_excitation_pin(st, chan_info->iout0);
1584 		if (ret)
1585 			return ret;
1586 	}
1587 
1588 	fwnode_property_read_u32(child, "adi,excitation-pin-1",
1589 				 &chan_info->iout1);
1590 	if (chan_info->setup.iout1_val != AD4130_IOUT_OFF) {
1591 		ret = ad4130_validate_excitation_pin(st, chan_info->iout1);
1592 		if (ret)
1593 			return ret;
1594 	}
1595 
1596 	return 0;
1597 }
1598 
1599 static int ad4130_parse_fw_children(struct iio_dev *indio_dev)
1600 {
1601 	struct ad4130_state *st = iio_priv(indio_dev);
1602 	struct device *dev = &st->spi->dev;
1603 	int ret;
1604 
1605 	indio_dev->channels = st->chans;
1606 
1607 	device_for_each_child_node_scoped(dev, child) {
1608 		ret = ad4130_parse_fw_channel(indio_dev, child);
1609 		if (ret)
1610 			return ret;
1611 	}
1612 
1613 	return 0;
1614 }
1615 
1616 static int ad4310_parse_fw(struct iio_dev *indio_dev)
1617 {
1618 	struct ad4130_state *st = iio_priv(indio_dev);
1619 	struct device *dev = &st->spi->dev;
1620 	u32 ext_clk_freq = AD4130_MCLK_FREQ_76_8KHZ;
1621 	unsigned int i;
1622 	int avdd_uv;
1623 	int irq;
1624 	int ret;
1625 
1626 	st->mclk = devm_clk_get_optional(dev, "mclk");
1627 	if (IS_ERR(st->mclk))
1628 		return dev_err_probe(dev, PTR_ERR(st->mclk),
1629 				     "Failed to get mclk\n");
1630 
1631 	st->int_pin_sel = AD4130_INT_PIN_INT;
1632 
1633 	for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) {
1634 		irq = fwnode_irq_get_byname(dev_fwnode(dev),
1635 					    ad4130_int_pin_names[i]);
1636 		if (irq > 0) {
1637 			st->int_pin_sel = i;
1638 			break;
1639 		}
1640 	}
1641 
1642 	if (st->int_pin_sel == AD4130_INT_PIN_DOUT)
1643 		return dev_err_probe(dev, -EINVAL,
1644 				     "Cannot use DOUT as interrupt pin\n");
1645 
1646 	if (st->int_pin_sel == AD4130_INT_PIN_P2)
1647 		st->pins_fn[AD4130_AIN3_P2] = AD4130_PIN_FN_SPECIAL;
1648 
1649 	device_property_read_u32(dev, "adi,ext-clk-freq-hz", &ext_clk_freq);
1650 	if (ext_clk_freq != AD4130_MCLK_FREQ_153_6KHZ &&
1651 	    ext_clk_freq != AD4130_MCLK_FREQ_76_8KHZ)
1652 		return dev_err_probe(dev, -EINVAL,
1653 				     "Invalid external clock frequency %u\n",
1654 				     ext_clk_freq);
1655 
1656 	if (st->mclk && ext_clk_freq == AD4130_MCLK_FREQ_153_6KHZ)
1657 		st->mclk_sel = AD4130_MCLK_153_6KHZ_EXT;
1658 	else if (st->mclk)
1659 		st->mclk_sel = AD4130_MCLK_76_8KHZ_EXT;
1660 	else
1661 		st->mclk_sel = AD4130_MCLK_76_8KHZ;
1662 
1663 	if (st->int_pin_sel == AD4130_INT_PIN_CLK &&
1664 	    st->mclk_sel != AD4130_MCLK_76_8KHZ)
1665 		return dev_err_probe(dev, -EINVAL,
1666 				     "Invalid clock %u for interrupt pin %u\n",
1667 				     st->mclk_sel, st->int_pin_sel);
1668 
1669 	st->int_ref_uv = AD4130_INT_REF_2_5V;
1670 
1671 	/*
1672 	 * When the AVDD supply is set to below 2.5V the internal reference of
1673 	 * 1.25V should be selected.
1674 	 * See datasheet page 37, section ADC REFERENCE.
1675 	 */
1676 	avdd_uv = regulator_get_voltage(st->regulators[0].consumer);
1677 	if (avdd_uv > 0 && avdd_uv < AD4130_INT_REF_2_5V)
1678 		st->int_ref_uv = AD4130_INT_REF_1_25V;
1679 
1680 	st->bipolar = device_property_read_bool(dev, "adi,bipolar");
1681 
1682 	ret = device_property_count_u32(dev, "adi,vbias-pins");
1683 	if (ret > 0) {
1684 		if (ret > AD4130_MAX_ANALOG_PINS)
1685 			return dev_err_probe(dev, -EINVAL,
1686 					     "Too many vbias pins %u\n", ret);
1687 
1688 		st->num_vbias_pins = ret;
1689 
1690 		ret = device_property_read_u32_array(dev, "adi,vbias-pins",
1691 						     st->vbias_pins,
1692 						     st->num_vbias_pins);
1693 		if (ret)
1694 			return dev_err_probe(dev, ret,
1695 					     "Failed to read vbias pins\n");
1696 
1697 		ret = ad4130_validate_vbias_pins(st, st->vbias_pins,
1698 						 st->num_vbias_pins);
1699 		if (ret)
1700 			return ret;
1701 	}
1702 
1703 	ret = ad4130_parse_fw_children(indio_dev);
1704 	if (ret)
1705 		return ret;
1706 
1707 	return 0;
1708 }
1709 
1710 static void ad4130_fill_scale_tbls(struct ad4130_state *st)
1711 {
1712 	unsigned int pow = ad4130_resolution(st) - st->bipolar;
1713 	unsigned int i, j;
1714 
1715 	for (i = 0; i < AD4130_REF_SEL_MAX; i++) {
1716 		int ret;
1717 		u64 nv;
1718 
1719 		ret = ad4130_get_ref_voltage(st, i);
1720 		if (ret < 0)
1721 			continue;
1722 
1723 		nv = (u64)ret * NANO;
1724 
1725 		for (j = 0; j < AD4130_MAX_PGA; j++)
1726 			st->scale_tbls[i][j][1] = div_u64(nv >> (pow + j), MILLI);
1727 	}
1728 }
1729 
1730 static void ad4130_clk_disable_unprepare(void *clk)
1731 {
1732 	clk_disable_unprepare(clk);
1733 }
1734 
1735 static int ad4130_set_mclk_sel(struct ad4130_state *st,
1736 			       enum ad4130_mclk_sel mclk_sel)
1737 {
1738 	return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
1739 				 AD4130_ADC_CONTROL_MCLK_SEL_MASK,
1740 				 FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK,
1741 					    mclk_sel));
1742 }
1743 
1744 static unsigned long ad4130_int_clk_recalc_rate(struct clk_hw *hw,
1745 						unsigned long parent_rate)
1746 {
1747 	return AD4130_MCLK_FREQ_76_8KHZ;
1748 }
1749 
1750 static int ad4130_int_clk_is_enabled(struct clk_hw *hw)
1751 {
1752 	struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1753 
1754 	return st->mclk_sel == AD4130_MCLK_76_8KHZ_OUT;
1755 }
1756 
1757 static int ad4130_int_clk_prepare(struct clk_hw *hw)
1758 {
1759 	struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1760 	int ret;
1761 
1762 	ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ_OUT);
1763 	if (ret)
1764 		return ret;
1765 
1766 	st->mclk_sel = AD4130_MCLK_76_8KHZ_OUT;
1767 
1768 	return 0;
1769 }
1770 
1771 static void ad4130_int_clk_unprepare(struct clk_hw *hw)
1772 {
1773 	struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1774 	int ret;
1775 
1776 	ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ);
1777 	if (ret)
1778 		return;
1779 
1780 	st->mclk_sel = AD4130_MCLK_76_8KHZ;
1781 }
1782 
1783 static const struct clk_ops ad4130_int_clk_ops = {
1784 	.recalc_rate = ad4130_int_clk_recalc_rate,
1785 	.is_enabled = ad4130_int_clk_is_enabled,
1786 	.prepare = ad4130_int_clk_prepare,
1787 	.unprepare = ad4130_int_clk_unprepare,
1788 };
1789 
1790 static int ad4130_setup_int_clk(struct ad4130_state *st)
1791 {
1792 	struct device *dev = &st->spi->dev;
1793 	struct device_node *of_node = dev_of_node(dev);
1794 	struct clk_init_data init = {};
1795 	const char *clk_name;
1796 	int ret;
1797 
1798 	if (st->int_pin_sel == AD4130_INT_PIN_CLK ||
1799 	    st->mclk_sel != AD4130_MCLK_76_8KHZ)
1800 		return 0;
1801 
1802 	if (!of_node)
1803 		return 0;
1804 
1805 	clk_name = of_node->name;
1806 	of_property_read_string(of_node, "clock-output-names", &clk_name);
1807 
1808 	init.name = clk_name;
1809 	init.ops = &ad4130_int_clk_ops;
1810 
1811 	st->int_clk_hw.init = &init;
1812 	ret = devm_clk_hw_register(dev, &st->int_clk_hw);
1813 	if (ret)
1814 		return ret;
1815 
1816 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
1817 					   &st->int_clk_hw);
1818 }
1819 
1820 static int ad4130_setup(struct iio_dev *indio_dev)
1821 {
1822 	struct ad4130_state *st = iio_priv(indio_dev);
1823 	struct device *dev = &st->spi->dev;
1824 	unsigned int int_ref_val;
1825 	unsigned long rate = AD4130_MCLK_FREQ_76_8KHZ;
1826 	unsigned int val;
1827 	unsigned int i;
1828 	int ret;
1829 
1830 	if (st->mclk_sel == AD4130_MCLK_153_6KHZ_EXT)
1831 		rate = AD4130_MCLK_FREQ_153_6KHZ;
1832 
1833 	ret = clk_set_rate(st->mclk, rate);
1834 	if (ret)
1835 		return ret;
1836 
1837 	ret = clk_prepare_enable(st->mclk);
1838 	if (ret)
1839 		return ret;
1840 
1841 	ret = devm_add_action_or_reset(dev, ad4130_clk_disable_unprepare,
1842 				       st->mclk);
1843 	if (ret)
1844 		return ret;
1845 
1846 	if (st->int_ref_uv == AD4130_INT_REF_2_5V)
1847 		int_ref_val = AD4130_INT_REF_VAL_2_5V;
1848 	else
1849 		int_ref_val = AD4130_INT_REF_VAL_1_25V;
1850 
1851 	/* Switch to SPI 4-wire mode. */
1852 	val =  FIELD_PREP(AD4130_ADC_CONTROL_CSB_EN_MASK, 1);
1853 	val |= FIELD_PREP(AD4130_ADC_CONTROL_BIPOLAR_MASK, st->bipolar);
1854 	val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_EN_MASK, st->int_ref_en);
1855 	val |= FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, AD4130_MODE_IDLE);
1856 	val |= FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, st->mclk_sel);
1857 	val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_VAL_MASK, int_ref_val);
1858 
1859 	ret = regmap_write(st->regmap, AD4130_ADC_CONTROL_REG, val);
1860 	if (ret)
1861 		return ret;
1862 
1863 	/*
1864 	 * Configure unused GPIOs for output. If configured, the interrupt
1865 	 * function of P2 takes priority over the GPIO out function.
1866 	 */
1867 	val = 0;
1868 	for (i = 0; i < AD4130_MAX_GPIOS; i++)
1869 		if (st->pins_fn[i + AD4130_AIN2_P1] == AD4130_PIN_FN_NONE)
1870 			val |= FIELD_PREP(AD4130_IO_CONTROL_GPIO_CTRL_MASK, BIT(i));
1871 
1872 	val |= FIELD_PREP(AD4130_IO_CONTROL_INT_PIN_SEL_MASK, st->int_pin_sel);
1873 
1874 	ret = regmap_write(st->regmap, AD4130_IO_CONTROL_REG, val);
1875 	if (ret)
1876 		return ret;
1877 
1878 	val = 0;
1879 	for (i = 0; i < st->num_vbias_pins; i++)
1880 		val |= BIT(st->vbias_pins[i]);
1881 
1882 	ret = regmap_write(st->regmap, AD4130_VBIAS_REG, val);
1883 	if (ret)
1884 		return ret;
1885 
1886 	ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
1887 				 AD4130_FIFO_CONTROL_HEADER_MASK, 0);
1888 	if (ret)
1889 		return ret;
1890 
1891 	/* FIFO watermark interrupt starts out as enabled, disable it. */
1892 	ret = ad4130_set_watermark_interrupt_en(st, false);
1893 	if (ret)
1894 		return ret;
1895 
1896 	/* Setup channels. */
1897 	for (i = 0; i < indio_dev->num_channels; i++) {
1898 		struct ad4130_chan_info *chan_info = &st->chans_info[i];
1899 		struct iio_chan_spec *chan = &st->chans[i];
1900 		unsigned int val;
1901 
1902 		val = FIELD_PREP(AD4130_CHANNEL_AINP_MASK, chan->channel) |
1903 		      FIELD_PREP(AD4130_CHANNEL_AINM_MASK, chan->channel2) |
1904 		      FIELD_PREP(AD4130_CHANNEL_IOUT1_MASK, chan_info->iout0) |
1905 		      FIELD_PREP(AD4130_CHANNEL_IOUT2_MASK, chan_info->iout1);
1906 
1907 		ret = regmap_write(st->regmap, AD4130_CHANNEL_X_REG(i), val);
1908 		if (ret)
1909 			return ret;
1910 	}
1911 
1912 	return 0;
1913 }
1914 
1915 static int ad4130_soft_reset(struct ad4130_state *st)
1916 {
1917 	int ret;
1918 
1919 	ret = spi_write(st->spi, st->reset_buf, sizeof(st->reset_buf));
1920 	if (ret)
1921 		return ret;
1922 
1923 	fsleep(AD4130_RESET_SLEEP_US);
1924 
1925 	return 0;
1926 }
1927 
1928 static void ad4130_disable_regulators(void *data)
1929 {
1930 	struct ad4130_state *st = data;
1931 
1932 	regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators);
1933 }
1934 
1935 static int ad4130_probe(struct spi_device *spi)
1936 {
1937 	struct device *dev = &spi->dev;
1938 	struct iio_dev *indio_dev;
1939 	struct ad4130_state *st;
1940 	int ret;
1941 
1942 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1943 	if (!indio_dev)
1944 		return -ENOMEM;
1945 
1946 	st = iio_priv(indio_dev);
1947 
1948 	memset(st->reset_buf, 0xff, sizeof(st->reset_buf));
1949 	init_completion(&st->completion);
1950 	mutex_init(&st->lock);
1951 	st->spi = spi;
1952 
1953 	/*
1954 	 * Xfer:   [ XFR1 ] [         XFR2         ]
1955 	 * Master:  0x7D N   ......................
1956 	 * Slave:   ......   DATA1 DATA2 ... DATAN
1957 	 */
1958 	st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_FIFO_DATA_REG;
1959 	st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
1960 	st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
1961 	st->fifo_xfer[1].rx_buf = st->fifo_rx_buf;
1962 	spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer,
1963 					ARRAY_SIZE(st->fifo_xfer));
1964 
1965 	indio_dev->name = AD4130_NAME;
1966 	indio_dev->modes = INDIO_DIRECT_MODE;
1967 	indio_dev->info = &ad4130_info;
1968 
1969 	st->regmap = devm_regmap_init(dev, NULL, st, &ad4130_regmap_config);
1970 	if (IS_ERR(st->regmap))
1971 		return PTR_ERR(st->regmap);
1972 
1973 	st->regulators[0].supply = "avdd";
1974 	st->regulators[1].supply = "iovdd";
1975 	st->regulators[2].supply = "refin1";
1976 	st->regulators[3].supply = "refin2";
1977 
1978 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators),
1979 				      st->regulators);
1980 	if (ret)
1981 		return dev_err_probe(dev, ret, "Failed to get regulators\n");
1982 
1983 	ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators);
1984 	if (ret)
1985 		return dev_err_probe(dev, ret, "Failed to enable regulators\n");
1986 
1987 	ret = devm_add_action_or_reset(dev, ad4130_disable_regulators, st);
1988 	if (ret)
1989 		return dev_err_probe(dev, ret,
1990 				     "Failed to add regulators disable action\n");
1991 
1992 	ret = ad4130_soft_reset(st);
1993 	if (ret)
1994 		return ret;
1995 
1996 	ret = ad4310_parse_fw(indio_dev);
1997 	if (ret)
1998 		return ret;
1999 
2000 	ret = ad4130_setup(indio_dev);
2001 	if (ret)
2002 		return ret;
2003 
2004 	ret = ad4130_setup_int_clk(st);
2005 	if (ret)
2006 		return ret;
2007 
2008 	ad4130_fill_scale_tbls(st);
2009 
2010 	st->gc.owner = THIS_MODULE;
2011 	st->gc.label = AD4130_NAME;
2012 	st->gc.base = -1;
2013 	st->gc.ngpio = AD4130_MAX_GPIOS;
2014 	st->gc.parent = dev;
2015 	st->gc.can_sleep = true;
2016 	st->gc.init_valid_mask = ad4130_gpio_init_valid_mask;
2017 	st->gc.get_direction = ad4130_gpio_get_direction;
2018 	st->gc.set = ad4130_gpio_set;
2019 
2020 	ret = devm_gpiochip_add_data(dev, &st->gc, st);
2021 	if (ret)
2022 		return ret;
2023 
2024 	ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev,
2025 					      &ad4130_buffer_ops,
2026 					      ad4130_fifo_attributes);
2027 	if (ret)
2028 		return ret;
2029 
2030 	ret = devm_request_threaded_irq(dev, spi->irq, NULL,
2031 					ad4130_irq_handler, IRQF_ONESHOT,
2032 					indio_dev->name, indio_dev);
2033 	if (ret)
2034 		return dev_err_probe(dev, ret, "Failed to request irq\n");
2035 
2036 	/*
2037 	 * When the chip enters FIFO mode, IRQ polarity is inverted.
2038 	 * When the chip exits FIFO mode, IRQ polarity returns to normal.
2039 	 * See datasheet pages: 65, FIFO Watermark Interrupt section,
2040 	 * and 71, Bit Descriptions for STATUS Register, RDYB.
2041 	 * Cache the normal and inverted IRQ triggers to set them when
2042 	 * entering and exiting FIFO mode.
2043 	 */
2044 	st->irq_trigger = irq_get_trigger_type(spi->irq);
2045 	if (st->irq_trigger & IRQF_TRIGGER_RISING)
2046 		st->inv_irq_trigger = IRQF_TRIGGER_FALLING;
2047 	else if (st->irq_trigger & IRQF_TRIGGER_FALLING)
2048 		st->inv_irq_trigger = IRQF_TRIGGER_RISING;
2049 	else
2050 		return dev_err_probe(dev, -EINVAL, "Invalid irq flags: %u\n",
2051 				     st->irq_trigger);
2052 
2053 	return devm_iio_device_register(dev, indio_dev);
2054 }
2055 
2056 static const struct of_device_id ad4130_of_match[] = {
2057 	{
2058 		.compatible = "adi,ad4130",
2059 	},
2060 	{ }
2061 };
2062 MODULE_DEVICE_TABLE(of, ad4130_of_match);
2063 
2064 static struct spi_driver ad4130_driver = {
2065 	.driver = {
2066 		.name = AD4130_NAME,
2067 		.of_match_table = ad4130_of_match,
2068 	},
2069 	.probe = ad4130_probe,
2070 };
2071 module_spi_driver(ad4130_driver);
2072 
2073 MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>");
2074 MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver");
2075 MODULE_LICENSE("GPL");
2076