xref: /kernel/linux/linux-5.10/drivers/iio/adc/ad7192.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * AD7190 AD7192 AD7193 AD7195 SPI ADC driver
4 *
5 * Copyright 2011-2015 Analog Devices Inc.
6 */
7
8#include <linux/interrupt.h>
9#include <linux/clk.h>
10#include <linux/device.h>
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/sysfs.h>
14#include <linux/spi/spi.h>
15#include <linux/regulator/consumer.h>
16#include <linux/err.h>
17#include <linux/sched.h>
18#include <linux/delay.h>
19#include <linux/of_device.h>
20
21#include <linux/iio/iio.h>
22#include <linux/iio/sysfs.h>
23#include <linux/iio/buffer.h>
24#include <linux/iio/trigger.h>
25#include <linux/iio/trigger_consumer.h>
26#include <linux/iio/triggered_buffer.h>
27#include <linux/iio/adc/ad_sigma_delta.h>
28
29/* Registers */
30#define AD7192_REG_COMM		0 /* Communications Register (WO, 8-bit) */
31#define AD7192_REG_STAT		0 /* Status Register	     (RO, 8-bit) */
32#define AD7192_REG_MODE		1 /* Mode Register	     (RW, 24-bit */
33#define AD7192_REG_CONF		2 /* Configuration Register  (RW, 24-bit) */
34#define AD7192_REG_DATA		3 /* Data Register	     (RO, 24/32-bit) */
35#define AD7192_REG_ID		4 /* ID Register	     (RO, 8-bit) */
36#define AD7192_REG_GPOCON	5 /* GPOCON Register	     (RO, 8-bit) */
37#define AD7192_REG_OFFSET	6 /* Offset Register	     (RW, 16-bit */
38				  /* (AD7792)/24-bit (AD7192)) */
39#define AD7192_REG_FULLSALE	7 /* Full-Scale Register */
40				  /* (RW, 16-bit (AD7792)/24-bit (AD7192)) */
41
42/* Communications Register Bit Designations (AD7192_REG_COMM) */
43#define AD7192_COMM_WEN		BIT(7) /* Write Enable */
44#define AD7192_COMM_WRITE	0 /* Write Operation */
45#define AD7192_COMM_READ	BIT(6) /* Read Operation */
46#define AD7192_COMM_ADDR(x)	(((x) & 0x7) << 3) /* Register Address */
47#define AD7192_COMM_CREAD	BIT(2) /* Continuous Read of Data Register */
48
49/* Status Register Bit Designations (AD7192_REG_STAT) */
50#define AD7192_STAT_RDY		BIT(7) /* Ready */
51#define AD7192_STAT_ERR		BIT(6) /* Error (Overrange, Underrange) */
52#define AD7192_STAT_NOREF	BIT(5) /* Error no external reference */
53#define AD7192_STAT_PARITY	BIT(4) /* Parity */
54#define AD7192_STAT_CH3		BIT(2) /* Channel 3 */
55#define AD7192_STAT_CH2		BIT(1) /* Channel 2 */
56#define AD7192_STAT_CH1		BIT(0) /* Channel 1 */
57
58/* Mode Register Bit Designations (AD7192_REG_MODE) */
59#define AD7192_MODE_SEL(x)	(((x) & 0x7) << 21) /* Operation Mode Select */
60#define AD7192_MODE_SEL_MASK	(0x7 << 21) /* Operation Mode Select Mask */
61#define AD7192_MODE_DAT_STA	BIT(20) /* Status Register transmission */
62#define AD7192_MODE_CLKSRC(x)	(((x) & 0x3) << 18) /* Clock Source Select */
63#define AD7192_MODE_SINC3	BIT(15) /* SINC3 Filter Select */
64#define AD7192_MODE_ACX		BIT(14) /* AC excitation enable(AD7195 only)*/
65#define AD7192_MODE_ENPAR	BIT(13) /* Parity Enable */
66#define AD7192_MODE_CLKDIV	BIT(12) /* Clock divide by 2 (AD7190/2 only)*/
67#define AD7192_MODE_SCYCLE	BIT(11) /* Single cycle conversion */
68#define AD7192_MODE_REJ60	BIT(10) /* 50/60Hz notch filter */
69#define AD7192_MODE_RATE(x)	((x) & 0x3FF) /* Filter Update Rate Select */
70
71/* Mode Register: AD7192_MODE_SEL options */
72#define AD7192_MODE_CONT		0 /* Continuous Conversion Mode */
73#define AD7192_MODE_SINGLE		1 /* Single Conversion Mode */
74#define AD7192_MODE_IDLE		2 /* Idle Mode */
75#define AD7192_MODE_PWRDN		3 /* Power-Down Mode */
76#define AD7192_MODE_CAL_INT_ZERO	4 /* Internal Zero-Scale Calibration */
77#define AD7192_MODE_CAL_INT_FULL	5 /* Internal Full-Scale Calibration */
78#define AD7192_MODE_CAL_SYS_ZERO	6 /* System Zero-Scale Calibration */
79#define AD7192_MODE_CAL_SYS_FULL	7 /* System Full-Scale Calibration */
80
81/* Mode Register: AD7192_MODE_CLKSRC options */
82#define AD7192_CLK_EXT_MCLK1_2		0 /* External 4.92 MHz Clock connected*/
83					  /* from MCLK1 to MCLK2 */
84#define AD7192_CLK_EXT_MCLK2		1 /* External Clock applied to MCLK2 */
85#define AD7192_CLK_INT			2 /* Internal 4.92 MHz Clock not */
86					  /* available at the MCLK2 pin */
87#define AD7192_CLK_INT_CO		3 /* Internal 4.92 MHz Clock available*/
88					  /* at the MCLK2 pin */
89
90/* Configuration Register Bit Designations (AD7192_REG_CONF) */
91
92#define AD7192_CONF_CHOP	BIT(23) /* CHOP enable */
93#define AD7192_CONF_REFSEL	BIT(20) /* REFIN1/REFIN2 Reference Select */
94#define AD7192_CONF_CHAN(x)	((x) << 8) /* Channel select */
95#define AD7192_CONF_CHAN_MASK	(0x7FF << 8) /* Channel select mask */
96#define AD7192_CONF_BURN	BIT(7) /* Burnout current enable */
97#define AD7192_CONF_REFDET	BIT(6) /* Reference detect enable */
98#define AD7192_CONF_BUF		BIT(4) /* Buffered Mode Enable */
99#define AD7192_CONF_UNIPOLAR	BIT(3) /* Unipolar/Bipolar Enable */
100#define AD7192_CONF_GAIN(x)	((x) & 0x7) /* Gain Select */
101
102#define AD7192_CH_AIN1P_AIN2M	BIT(0) /* AIN1(+) - AIN2(-) */
103#define AD7192_CH_AIN3P_AIN4M	BIT(1) /* AIN3(+) - AIN4(-) */
104#define AD7192_CH_TEMP		BIT(2) /* Temp Sensor */
105#define AD7192_CH_AIN2P_AIN2M	BIT(3) /* AIN2(+) - AIN2(-) */
106#define AD7192_CH_AIN1		BIT(4) /* AIN1 - AINCOM */
107#define AD7192_CH_AIN2		BIT(5) /* AIN2 - AINCOM */
108#define AD7192_CH_AIN3		BIT(6) /* AIN3 - AINCOM */
109#define AD7192_CH_AIN4		BIT(7) /* AIN4 - AINCOM */
110
111#define AD7193_CH_AIN1P_AIN2M	0x001  /* AIN1(+) - AIN2(-) */
112#define AD7193_CH_AIN3P_AIN4M	0x002  /* AIN3(+) - AIN4(-) */
113#define AD7193_CH_AIN5P_AIN6M	0x004  /* AIN5(+) - AIN6(-) */
114#define AD7193_CH_AIN7P_AIN8M	0x008  /* AIN7(+) - AIN8(-) */
115#define AD7193_CH_TEMP		0x100 /* Temp senseor */
116#define AD7193_CH_AIN2P_AIN2M	0x200 /* AIN2(+) - AIN2(-) */
117#define AD7193_CH_AIN1		0x401 /* AIN1 - AINCOM */
118#define AD7193_CH_AIN2		0x402 /* AIN2 - AINCOM */
119#define AD7193_CH_AIN3		0x404 /* AIN3 - AINCOM */
120#define AD7193_CH_AIN4		0x408 /* AIN4 - AINCOM */
121#define AD7193_CH_AIN5		0x410 /* AIN5 - AINCOM */
122#define AD7193_CH_AIN6		0x420 /* AIN6 - AINCOM */
123#define AD7193_CH_AIN7		0x440 /* AIN7 - AINCOM */
124#define AD7193_CH_AIN8		0x480 /* AIN7 - AINCOM */
125#define AD7193_CH_AINCOM	0x600 /* AINCOM - AINCOM */
126
127/* ID Register Bit Designations (AD7192_REG_ID) */
128#define CHIPID_AD7190		0x4
129#define CHIPID_AD7192		0x0
130#define CHIPID_AD7193		0x2
131#define CHIPID_AD7195		0x6
132#define AD7192_ID_MASK		0x0F
133
134/* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
135#define AD7192_GPOCON_BPDSW	BIT(6) /* Bridge power-down switch enable */
136#define AD7192_GPOCON_GP32EN	BIT(5) /* Digital Output P3 and P2 enable */
137#define AD7192_GPOCON_GP10EN	BIT(4) /* Digital Output P1 and P0 enable */
138#define AD7192_GPOCON_P3DAT	BIT(3) /* P3 state */
139#define AD7192_GPOCON_P2DAT	BIT(2) /* P2 state */
140#define AD7192_GPOCON_P1DAT	BIT(1) /* P1 state */
141#define AD7192_GPOCON_P0DAT	BIT(0) /* P0 state */
142
143#define AD7192_EXT_FREQ_MHZ_MIN	2457600
144#define AD7192_EXT_FREQ_MHZ_MAX	5120000
145#define AD7192_INT_FREQ_MHZ	4915200
146
147#define AD7192_NO_SYNC_FILTER	1
148#define AD7192_SYNC3_FILTER	3
149#define AD7192_SYNC4_FILTER	4
150
151/* NOTE:
152 * The AD7190/2/5 features a dual use data out ready DOUT/RDY output.
153 * In order to avoid contentions on the SPI bus, it's therefore necessary
154 * to use spi bus locking.
155 *
156 * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
157 */
158
159enum {
160	AD7192_SYSCALIB_ZERO_SCALE,
161	AD7192_SYSCALIB_FULL_SCALE,
162};
163
164enum {
165	ID_AD7190,
166	ID_AD7192,
167	ID_AD7193,
168	ID_AD7195,
169};
170
171struct ad7192_chip_info {
172	unsigned int			chip_id;
173	const char			*name;
174};
175
176struct ad7192_state {
177	const struct ad7192_chip_info	*chip_info;
178	struct regulator		*avdd;
179	struct regulator		*dvdd;
180	struct clk			*mclk;
181	u16				int_vref_mv;
182	u32				fclk;
183	u32				f_order;
184	u32				mode;
185	u32				conf;
186	u32				scale_avail[8][2];
187	u8				gpocon;
188	u8				clock_sel;
189	struct mutex			lock;	/* protect sensor state */
190	u8				syscalib_mode[8];
191
192	struct ad_sigma_delta		sd;
193};
194
195static const char * const ad7192_syscalib_modes[] = {
196	[AD7192_SYSCALIB_ZERO_SCALE] = "zero_scale",
197	[AD7192_SYSCALIB_FULL_SCALE] = "full_scale",
198};
199
200static int ad7192_set_syscalib_mode(struct iio_dev *indio_dev,
201				    const struct iio_chan_spec *chan,
202				    unsigned int mode)
203{
204	struct ad7192_state *st = iio_priv(indio_dev);
205
206	st->syscalib_mode[chan->channel] = mode;
207
208	return 0;
209}
210
211static int ad7192_get_syscalib_mode(struct iio_dev *indio_dev,
212				    const struct iio_chan_spec *chan)
213{
214	struct ad7192_state *st = iio_priv(indio_dev);
215
216	return st->syscalib_mode[chan->channel];
217}
218
219static ssize_t ad7192_write_syscalib(struct iio_dev *indio_dev,
220				     uintptr_t private,
221				     const struct iio_chan_spec *chan,
222				     const char *buf, size_t len)
223{
224	struct ad7192_state *st = iio_priv(indio_dev);
225	bool sys_calib;
226	int ret, temp;
227
228	ret = strtobool(buf, &sys_calib);
229	if (ret)
230		return ret;
231
232	temp = st->syscalib_mode[chan->channel];
233	if (sys_calib) {
234		if (temp == AD7192_SYSCALIB_ZERO_SCALE)
235			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_ZERO,
236					      chan->address);
237		else
238			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_FULL,
239					      chan->address);
240	}
241
242	return ret ? ret : len;
243}
244
245static const struct iio_enum ad7192_syscalib_mode_enum = {
246	.items = ad7192_syscalib_modes,
247	.num_items = ARRAY_SIZE(ad7192_syscalib_modes),
248	.set = ad7192_set_syscalib_mode,
249	.get = ad7192_get_syscalib_mode
250};
251
252static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = {
253	{
254		.name = "sys_calibration",
255		.write = ad7192_write_syscalib,
256		.shared = IIO_SEPARATE,
257	},
258	IIO_ENUM("sys_calibration_mode", IIO_SEPARATE,
259		 &ad7192_syscalib_mode_enum),
260	IIO_ENUM_AVAILABLE("sys_calibration_mode", &ad7192_syscalib_mode_enum),
261	{}
262};
263
264static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd)
265{
266	return container_of(sd, struct ad7192_state, sd);
267}
268
269static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
270{
271	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
272
273	st->conf &= ~AD7192_CONF_CHAN_MASK;
274	st->conf |= AD7192_CONF_CHAN(channel);
275
276	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
277}
278
279static int ad7192_set_mode(struct ad_sigma_delta *sd,
280			   enum ad_sigma_delta_mode mode)
281{
282	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
283
284	st->mode &= ~AD7192_MODE_SEL_MASK;
285	st->mode |= AD7192_MODE_SEL(mode);
286
287	return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
288}
289
290static const struct ad_sigma_delta_info ad7192_sigma_delta_info = {
291	.set_channel = ad7192_set_channel,
292	.set_mode = ad7192_set_mode,
293	.has_registers = true,
294	.addr_shift = 3,
295	.read_mask = BIT(6),
296	.irq_flags = IRQF_TRIGGER_FALLING,
297};
298
299static const struct ad_sd_calib_data ad7192_calib_arr[8] = {
300	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
301	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
302	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
303	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
304	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
305	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
306	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
307	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
308};
309
310static int ad7192_calibrate_all(struct ad7192_state *st)
311{
312	return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr,
313				   ARRAY_SIZE(ad7192_calib_arr));
314}
315
316static inline bool ad7192_valid_external_frequency(u32 freq)
317{
318	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
319		freq <= AD7192_EXT_FREQ_MHZ_MAX);
320}
321
322static int ad7192_of_clock_select(struct ad7192_state *st)
323{
324	struct device_node *np = st->sd.spi->dev.of_node;
325	unsigned int clock_sel;
326
327	clock_sel = AD7192_CLK_INT;
328
329	/* use internal clock */
330	if (PTR_ERR(st->mclk) == -ENOENT) {
331		if (of_property_read_bool(np, "adi,int-clock-output-enable"))
332			clock_sel = AD7192_CLK_INT_CO;
333	} else {
334		if (of_property_read_bool(np, "adi,clock-xtal"))
335			clock_sel = AD7192_CLK_EXT_MCLK1_2;
336		else
337			clock_sel = AD7192_CLK_EXT_MCLK2;
338	}
339
340	return clock_sel;
341}
342
343static int ad7192_setup(struct ad7192_state *st, struct device_node *np)
344{
345	struct iio_dev *indio_dev = spi_get_drvdata(st->sd.spi);
346	bool rej60_en, refin2_en;
347	bool buf_en, bipolar, burnout_curr_en;
348	unsigned long long scale_uv;
349	int i, ret, id;
350
351	/* reset the serial interface */
352	ret = ad_sd_reset(&st->sd, 48);
353	if (ret < 0)
354		return ret;
355	usleep_range(500, 1000); /* Wait for at least 500us */
356
357	/* write/read test for device presence */
358	ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id);
359	if (ret)
360		return ret;
361
362	id &= AD7192_ID_MASK;
363
364	if (id != st->chip_info->chip_id)
365		dev_warn(&st->sd.spi->dev, "device ID query failed (0x%X)\n",
366			 id);
367
368	st->mode = AD7192_MODE_SEL(AD7192_MODE_IDLE) |
369		AD7192_MODE_CLKSRC(st->clock_sel) |
370		AD7192_MODE_RATE(480);
371
372	st->conf = AD7192_CONF_GAIN(0);
373
374	rej60_en = of_property_read_bool(np, "adi,rejection-60-Hz-enable");
375	if (rej60_en)
376		st->mode |= AD7192_MODE_REJ60;
377
378	refin2_en = of_property_read_bool(np, "adi,refin2-pins-enable");
379	if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195)
380		st->conf |= AD7192_CONF_REFSEL;
381
382	st->conf &= ~AD7192_CONF_CHOP;
383	st->f_order = AD7192_NO_SYNC_FILTER;
384
385	buf_en = of_property_read_bool(np, "adi,buffer-enable");
386	if (buf_en)
387		st->conf |= AD7192_CONF_BUF;
388
389	bipolar = of_property_read_bool(np, "bipolar");
390	if (!bipolar)
391		st->conf |= AD7192_CONF_UNIPOLAR;
392
393	burnout_curr_en = of_property_read_bool(np,
394						"adi,burnout-currents-enable");
395	if (burnout_curr_en && buf_en) {
396		st->conf |= AD7192_CONF_BURN;
397	} else if (burnout_curr_en) {
398		dev_warn(&st->sd.spi->dev,
399			 "Can't enable burnout currents: see CHOP or buffer\n");
400	}
401
402	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
403	if (ret)
404		return ret;
405
406	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
407	if (ret)
408		return ret;
409
410	ret = ad7192_calibrate_all(st);
411	if (ret)
412		return ret;
413
414	/* Populate available ADC input ranges */
415	for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
416		scale_uv = ((u64)st->int_vref_mv * 100000000)
417			>> (indio_dev->channels[0].scan_type.realbits -
418			((st->conf & AD7192_CONF_UNIPOLAR) ? 0 : 1));
419		scale_uv >>= i;
420
421		st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
422		st->scale_avail[i][0] = scale_uv;
423	}
424
425	return 0;
426}
427
428static ssize_t ad7192_show_ac_excitation(struct device *dev,
429					 struct device_attribute *attr,
430					 char *buf)
431{
432	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
433	struct ad7192_state *st = iio_priv(indio_dev);
434
435	return sprintf(buf, "%d\n", !!(st->mode & AD7192_MODE_ACX));
436}
437
438static ssize_t ad7192_show_bridge_switch(struct device *dev,
439					 struct device_attribute *attr,
440					 char *buf)
441{
442	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
443	struct ad7192_state *st = iio_priv(indio_dev);
444
445	return sprintf(buf, "%d\n", !!(st->gpocon & AD7192_GPOCON_BPDSW));
446}
447
448static ssize_t ad7192_set(struct device *dev,
449			  struct device_attribute *attr,
450			  const char *buf,
451			  size_t len)
452{
453	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
454	struct ad7192_state *st = iio_priv(indio_dev);
455	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
456	int ret;
457	bool val;
458
459	ret = strtobool(buf, &val);
460	if (ret < 0)
461		return ret;
462
463	ret = iio_device_claim_direct_mode(indio_dev);
464	if (ret)
465		return ret;
466
467	switch ((u32)this_attr->address) {
468	case AD7192_REG_GPOCON:
469		if (val)
470			st->gpocon |= AD7192_GPOCON_BPDSW;
471		else
472			st->gpocon &= ~AD7192_GPOCON_BPDSW;
473
474		ad_sd_write_reg(&st->sd, AD7192_REG_GPOCON, 1, st->gpocon);
475		break;
476	case AD7192_REG_MODE:
477		if (val)
478			st->mode |= AD7192_MODE_ACX;
479		else
480			st->mode &= ~AD7192_MODE_ACX;
481
482		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
483		break;
484	default:
485		ret = -EINVAL;
486	}
487
488	iio_device_release_direct_mode(indio_dev);
489
490	return ret ? ret : len;
491}
492
493static void ad7192_get_available_filter_freq(struct ad7192_state *st,
494						    int *freq)
495{
496	unsigned int fadc;
497
498	/* Formulas for filter at page 25 of the datasheet */
499	fadc = DIV_ROUND_CLOSEST(st->fclk,
500				 AD7192_SYNC4_FILTER * AD7192_MODE_RATE(st->mode));
501	freq[0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
502
503	fadc = DIV_ROUND_CLOSEST(st->fclk,
504				 AD7192_SYNC3_FILTER * AD7192_MODE_RATE(st->mode));
505	freq[1] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
506
507	fadc = DIV_ROUND_CLOSEST(st->fclk, AD7192_MODE_RATE(st->mode));
508	freq[2] = DIV_ROUND_CLOSEST(fadc * 230, 1024);
509	freq[3] = DIV_ROUND_CLOSEST(fadc * 272, 1024);
510}
511
512static ssize_t ad7192_show_filter_avail(struct device *dev,
513					struct device_attribute *attr,
514					char *buf)
515{
516	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
517	struct ad7192_state *st = iio_priv(indio_dev);
518	unsigned int freq_avail[4], i;
519	size_t len = 0;
520
521	ad7192_get_available_filter_freq(st, freq_avail);
522
523	for (i = 0; i < ARRAY_SIZE(freq_avail); i++)
524		len += scnprintf(buf + len, PAGE_SIZE - len,
525				 "%d.%d ", freq_avail[i] / 1000,
526				 freq_avail[i] % 1000);
527
528	buf[len - 1] = '\n';
529
530	return len;
531}
532
533static IIO_DEVICE_ATTR(filter_low_pass_3db_frequency_available,
534		       0444, ad7192_show_filter_avail, NULL, 0);
535
536static IIO_DEVICE_ATTR(bridge_switch_en, 0644,
537		       ad7192_show_bridge_switch, ad7192_set,
538		       AD7192_REG_GPOCON);
539
540static IIO_DEVICE_ATTR(ac_excitation_en, 0644,
541		       ad7192_show_ac_excitation, ad7192_set,
542		       AD7192_REG_MODE);
543
544static struct attribute *ad7192_attributes[] = {
545	&iio_dev_attr_filter_low_pass_3db_frequency_available.dev_attr.attr,
546	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
547	&iio_dev_attr_ac_excitation_en.dev_attr.attr,
548	NULL
549};
550
551static const struct attribute_group ad7192_attribute_group = {
552	.attrs = ad7192_attributes,
553};
554
555static struct attribute *ad7195_attributes[] = {
556	&iio_dev_attr_filter_low_pass_3db_frequency_available.dev_attr.attr,
557	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
558	NULL
559};
560
561static const struct attribute_group ad7195_attribute_group = {
562	.attrs = ad7195_attributes,
563};
564
565static unsigned int ad7192_get_temp_scale(bool unipolar)
566{
567	return unipolar ? 2815 * 2 : 2815;
568}
569
570static int ad7192_set_3db_filter_freq(struct ad7192_state *st,
571				      int val, int val2)
572{
573	int freq_avail[4], i, ret, freq;
574	unsigned int diff_new, diff_old;
575	int idx = 0;
576
577	diff_old = U32_MAX;
578	freq = val * 1000 + val2;
579
580	ad7192_get_available_filter_freq(st, freq_avail);
581
582	for (i = 0; i < ARRAY_SIZE(freq_avail); i++) {
583		diff_new = abs(freq - freq_avail[i]);
584		if (diff_new < diff_old) {
585			diff_old = diff_new;
586			idx = i;
587		}
588	}
589
590	switch (idx) {
591	case 0:
592		st->f_order = AD7192_SYNC4_FILTER;
593		st->mode &= ~AD7192_MODE_SINC3;
594
595		st->conf |= AD7192_CONF_CHOP;
596		break;
597	case 1:
598		st->f_order = AD7192_SYNC3_FILTER;
599		st->mode |= AD7192_MODE_SINC3;
600
601		st->conf |= AD7192_CONF_CHOP;
602		break;
603	case 2:
604		st->f_order = AD7192_NO_SYNC_FILTER;
605		st->mode &= ~AD7192_MODE_SINC3;
606
607		st->conf &= ~AD7192_CONF_CHOP;
608		break;
609	case 3:
610		st->f_order = AD7192_NO_SYNC_FILTER;
611		st->mode |= AD7192_MODE_SINC3;
612
613		st->conf &= ~AD7192_CONF_CHOP;
614		break;
615	}
616
617	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
618	if (ret < 0)
619		return ret;
620
621	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
622}
623
624static int ad7192_get_3db_filter_freq(struct ad7192_state *st)
625{
626	unsigned int fadc;
627
628	fadc = DIV_ROUND_CLOSEST(st->fclk,
629				 st->f_order * AD7192_MODE_RATE(st->mode));
630
631	if (st->conf & AD7192_CONF_CHOP)
632		return DIV_ROUND_CLOSEST(fadc * 240, 1024);
633	if (st->mode & AD7192_MODE_SINC3)
634		return DIV_ROUND_CLOSEST(fadc * 272, 1024);
635	else
636		return DIV_ROUND_CLOSEST(fadc * 230, 1024);
637}
638
639static int ad7192_read_raw(struct iio_dev *indio_dev,
640			   struct iio_chan_spec const *chan,
641			   int *val,
642			   int *val2,
643			   long m)
644{
645	struct ad7192_state *st = iio_priv(indio_dev);
646	bool unipolar = !!(st->conf & AD7192_CONF_UNIPOLAR);
647
648	switch (m) {
649	case IIO_CHAN_INFO_RAW:
650		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
651	case IIO_CHAN_INFO_SCALE:
652		switch (chan->type) {
653		case IIO_VOLTAGE:
654			mutex_lock(&st->lock);
655			*val = st->scale_avail[AD7192_CONF_GAIN(st->conf)][0];
656			*val2 = st->scale_avail[AD7192_CONF_GAIN(st->conf)][1];
657			mutex_unlock(&st->lock);
658			return IIO_VAL_INT_PLUS_NANO;
659		case IIO_TEMP:
660			*val = 0;
661			*val2 = 1000000000 / ad7192_get_temp_scale(unipolar);
662			return IIO_VAL_INT_PLUS_NANO;
663		default:
664			return -EINVAL;
665		}
666	case IIO_CHAN_INFO_OFFSET:
667		if (!unipolar)
668			*val = -(1 << (chan->scan_type.realbits - 1));
669		else
670			*val = 0;
671		/* Kelvin to Celsius */
672		if (chan->type == IIO_TEMP)
673			*val -= 273 * ad7192_get_temp_scale(unipolar);
674		return IIO_VAL_INT;
675	case IIO_CHAN_INFO_SAMP_FREQ:
676		*val = st->fclk /
677			(st->f_order * 1024 * AD7192_MODE_RATE(st->mode));
678		return IIO_VAL_INT;
679	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
680		*val = ad7192_get_3db_filter_freq(st);
681		*val2 = 1000;
682		return IIO_VAL_FRACTIONAL;
683	}
684
685	return -EINVAL;
686}
687
688static int ad7192_write_raw(struct iio_dev *indio_dev,
689			    struct iio_chan_spec const *chan,
690			    int val,
691			    int val2,
692			    long mask)
693{
694	struct ad7192_state *st = iio_priv(indio_dev);
695	int ret, i, div;
696	unsigned int tmp;
697
698	ret = iio_device_claim_direct_mode(indio_dev);
699	if (ret)
700		return ret;
701
702	switch (mask) {
703	case IIO_CHAN_INFO_SCALE:
704		ret = -EINVAL;
705		mutex_lock(&st->lock);
706		for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
707			if (val2 == st->scale_avail[i][1]) {
708				ret = 0;
709				tmp = st->conf;
710				st->conf &= ~AD7192_CONF_GAIN(-1);
711				st->conf |= AD7192_CONF_GAIN(i);
712				if (tmp == st->conf)
713					break;
714				ad_sd_write_reg(&st->sd, AD7192_REG_CONF,
715						3, st->conf);
716				ad7192_calibrate_all(st);
717				break;
718			}
719		mutex_unlock(&st->lock);
720		break;
721	case IIO_CHAN_INFO_SAMP_FREQ:
722		if (!val) {
723			ret = -EINVAL;
724			break;
725		}
726
727		div = st->fclk / (val * st->f_order * 1024);
728		if (div < 1 || div > 1023) {
729			ret = -EINVAL;
730			break;
731		}
732
733		st->mode &= ~AD7192_MODE_RATE(-1);
734		st->mode |= AD7192_MODE_RATE(div);
735		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
736		break;
737	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
738		ret = ad7192_set_3db_filter_freq(st, val, val2 / 1000);
739		break;
740	default:
741		ret = -EINVAL;
742	}
743
744	iio_device_release_direct_mode(indio_dev);
745
746	return ret;
747}
748
749static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
750				    struct iio_chan_spec const *chan,
751				    long mask)
752{
753	switch (mask) {
754	case IIO_CHAN_INFO_SCALE:
755		return IIO_VAL_INT_PLUS_NANO;
756	case IIO_CHAN_INFO_SAMP_FREQ:
757		return IIO_VAL_INT;
758	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
759		return IIO_VAL_INT_PLUS_MICRO;
760	default:
761		return -EINVAL;
762	}
763}
764
765static int ad7192_read_avail(struct iio_dev *indio_dev,
766			     struct iio_chan_spec const *chan,
767			     const int **vals, int *type, int *length,
768			     long mask)
769{
770	struct ad7192_state *st = iio_priv(indio_dev);
771
772	switch (mask) {
773	case IIO_CHAN_INFO_SCALE:
774		*vals = (int *)st->scale_avail;
775		*type = IIO_VAL_INT_PLUS_NANO;
776		/* Values are stored in a 2D matrix  */
777		*length = ARRAY_SIZE(st->scale_avail) * 2;
778
779		return IIO_AVAIL_LIST;
780	}
781
782	return -EINVAL;
783}
784
785static const struct iio_info ad7192_info = {
786	.read_raw = ad7192_read_raw,
787	.write_raw = ad7192_write_raw,
788	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
789	.read_avail = ad7192_read_avail,
790	.attrs = &ad7192_attribute_group,
791	.validate_trigger = ad_sd_validate_trigger,
792};
793
794static const struct iio_info ad7195_info = {
795	.read_raw = ad7192_read_raw,
796	.write_raw = ad7192_write_raw,
797	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
798	.read_avail = ad7192_read_avail,
799	.attrs = &ad7195_attribute_group,
800	.validate_trigger = ad_sd_validate_trigger,
801};
802
803#define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _extend_name, \
804	_type, _mask_type_av, _ext_info) \
805	{ \
806		.type = (_type), \
807		.differential = ((_channel2) == -1 ? 0 : 1), \
808		.indexed = 1, \
809		.channel = (_channel1), \
810		.channel2 = (_channel2), \
811		.address = (_address), \
812		.extend_name = (_extend_name), \
813		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
814			BIT(IIO_CHAN_INFO_OFFSET), \
815		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
816		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
817			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \
818		.info_mask_shared_by_type_available = (_mask_type_av), \
819		.ext_info = (_ext_info), \
820		.scan_index = (_si), \
821		.scan_type = { \
822			.sign = 'u', \
823			.realbits = 24, \
824			.storagebits = 32, \
825			.endianness = IIO_BE, \
826		}, \
827	}
828
829#define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
830	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, NULL, \
831		IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE), \
832		ad7192_calibsys_ext_info)
833
834#define AD719x_CHANNEL(_si, _channel1, _address) \
835	__AD719x_CHANNEL(_si, _channel1, -1, _address, NULL, IIO_VOLTAGE, \
836		BIT(IIO_CHAN_INFO_SCALE), ad7192_calibsys_ext_info)
837
838#define AD719x_TEMP_CHANNEL(_si, _address) \
839	__AD719x_CHANNEL(_si, 0, -1, _address, NULL, IIO_TEMP, 0, NULL)
840
841static const struct iio_chan_spec ad7192_channels[] = {
842	AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
843	AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
844	AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
845	AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M),
846	AD719x_CHANNEL(4, 1, AD7192_CH_AIN1),
847	AD719x_CHANNEL(5, 2, AD7192_CH_AIN2),
848	AD719x_CHANNEL(6, 3, AD7192_CH_AIN3),
849	AD719x_CHANNEL(7, 4, AD7192_CH_AIN4),
850	IIO_CHAN_SOFT_TIMESTAMP(8),
851};
852
853static const struct iio_chan_spec ad7193_channels[] = {
854	AD719x_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
855	AD719x_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
856	AD719x_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
857	AD719x_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M),
858	AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP),
859	AD719x_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M),
860	AD719x_CHANNEL(6, 1, AD7193_CH_AIN1),
861	AD719x_CHANNEL(7, 2, AD7193_CH_AIN2),
862	AD719x_CHANNEL(8, 3, AD7193_CH_AIN3),
863	AD719x_CHANNEL(9, 4, AD7193_CH_AIN4),
864	AD719x_CHANNEL(10, 5, AD7193_CH_AIN5),
865	AD719x_CHANNEL(11, 6, AD7193_CH_AIN6),
866	AD719x_CHANNEL(12, 7, AD7193_CH_AIN7),
867	AD719x_CHANNEL(13, 8, AD7193_CH_AIN8),
868	IIO_CHAN_SOFT_TIMESTAMP(14),
869};
870
871static const struct ad7192_chip_info ad7192_chip_info_tbl[] = {
872	[ID_AD7190] = {
873		.chip_id = CHIPID_AD7190,
874		.name = "ad7190",
875	},
876	[ID_AD7192] = {
877		.chip_id = CHIPID_AD7192,
878		.name = "ad7192",
879	},
880	[ID_AD7193] = {
881		.chip_id = CHIPID_AD7193,
882		.name = "ad7193",
883	},
884	[ID_AD7195] = {
885		.chip_id = CHIPID_AD7195,
886		.name = "ad7195",
887	},
888};
889
890static int ad7192_channels_config(struct iio_dev *indio_dev)
891{
892	struct ad7192_state *st = iio_priv(indio_dev);
893
894	switch (st->chip_info->chip_id) {
895	case CHIPID_AD7193:
896		indio_dev->channels = ad7193_channels;
897		indio_dev->num_channels = ARRAY_SIZE(ad7193_channels);
898		break;
899	default:
900		indio_dev->channels = ad7192_channels;
901		indio_dev->num_channels = ARRAY_SIZE(ad7192_channels);
902		break;
903	}
904
905	return 0;
906}
907
908static int ad7192_probe(struct spi_device *spi)
909{
910	struct ad7192_state *st;
911	struct iio_dev *indio_dev;
912	int ret;
913
914	if (!spi->irq) {
915		dev_err(&spi->dev, "no IRQ?\n");
916		return -ENODEV;
917	}
918
919	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
920	if (!indio_dev)
921		return -ENOMEM;
922
923	st = iio_priv(indio_dev);
924
925	mutex_init(&st->lock);
926
927	st->avdd = devm_regulator_get(&spi->dev, "avdd");
928	if (IS_ERR(st->avdd))
929		return PTR_ERR(st->avdd);
930
931	ret = regulator_enable(st->avdd);
932	if (ret) {
933		dev_err(&spi->dev, "Failed to enable specified AVdd supply\n");
934		return ret;
935	}
936
937	st->dvdd = devm_regulator_get(&spi->dev, "dvdd");
938	if (IS_ERR(st->dvdd)) {
939		ret = PTR_ERR(st->dvdd);
940		goto error_disable_avdd;
941	}
942
943	ret = regulator_enable(st->dvdd);
944	if (ret) {
945		dev_err(&spi->dev, "Failed to enable specified DVdd supply\n");
946		goto error_disable_avdd;
947	}
948
949	ret = regulator_get_voltage(st->avdd);
950	if (ret < 0) {
951		dev_err(&spi->dev, "Device tree error, reference voltage undefined\n");
952		goto error_disable_avdd;
953	}
954	st->int_vref_mv = ret / 1000;
955
956	spi_set_drvdata(spi, indio_dev);
957	st->chip_info = of_device_get_match_data(&spi->dev);
958	indio_dev->name = st->chip_info->name;
959	indio_dev->modes = INDIO_DIRECT_MODE;
960
961	ret = ad7192_channels_config(indio_dev);
962	if (ret < 0)
963		goto error_disable_dvdd;
964
965	if (st->chip_info->chip_id == CHIPID_AD7195)
966		indio_dev->info = &ad7195_info;
967	else
968		indio_dev->info = &ad7192_info;
969
970	ad_sd_init(&st->sd, indio_dev, spi, &ad7192_sigma_delta_info);
971
972	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
973	if (ret)
974		goto error_disable_dvdd;
975
976	st->fclk = AD7192_INT_FREQ_MHZ;
977
978	st->mclk = devm_clk_get(&st->sd.spi->dev, "mclk");
979	if (IS_ERR(st->mclk) && PTR_ERR(st->mclk) != -ENOENT) {
980		ret = PTR_ERR(st->mclk);
981		goto error_remove_trigger;
982	}
983
984	st->clock_sel = ad7192_of_clock_select(st);
985
986	if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
987	    st->clock_sel == AD7192_CLK_EXT_MCLK2) {
988		ret = clk_prepare_enable(st->mclk);
989		if (ret < 0)
990			goto error_remove_trigger;
991
992		st->fclk = clk_get_rate(st->mclk);
993		if (!ad7192_valid_external_frequency(st->fclk)) {
994			ret = -EINVAL;
995			dev_err(&spi->dev,
996				"External clock frequency out of bounds\n");
997			goto error_disable_clk;
998		}
999	}
1000
1001	ret = ad7192_setup(st, spi->dev.of_node);
1002	if (ret)
1003		goto error_disable_clk;
1004
1005	ret = iio_device_register(indio_dev);
1006	if (ret < 0)
1007		goto error_disable_clk;
1008	return 0;
1009
1010error_disable_clk:
1011	if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
1012	    st->clock_sel == AD7192_CLK_EXT_MCLK2)
1013		clk_disable_unprepare(st->mclk);
1014error_remove_trigger:
1015	ad_sd_cleanup_buffer_and_trigger(indio_dev);
1016error_disable_dvdd:
1017	regulator_disable(st->dvdd);
1018error_disable_avdd:
1019	regulator_disable(st->avdd);
1020
1021	return ret;
1022}
1023
1024static int ad7192_remove(struct spi_device *spi)
1025{
1026	struct iio_dev *indio_dev = spi_get_drvdata(spi);
1027	struct ad7192_state *st = iio_priv(indio_dev);
1028
1029	iio_device_unregister(indio_dev);
1030	if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
1031	    st->clock_sel == AD7192_CLK_EXT_MCLK2)
1032		clk_disable_unprepare(st->mclk);
1033	ad_sd_cleanup_buffer_and_trigger(indio_dev);
1034
1035	regulator_disable(st->dvdd);
1036	regulator_disable(st->avdd);
1037
1038	return 0;
1039}
1040
1041static const struct of_device_id ad7192_of_match[] = {
1042	{ .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] },
1043	{ .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] },
1044	{ .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] },
1045	{ .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] },
1046	{}
1047};
1048MODULE_DEVICE_TABLE(of, ad7192_of_match);
1049
1050static struct spi_driver ad7192_driver = {
1051	.driver = {
1052		.name	= "ad7192",
1053		.of_match_table = ad7192_of_match,
1054	},
1055	.probe		= ad7192_probe,
1056	.remove		= ad7192_remove,
1057};
1058module_spi_driver(ad7192_driver);
1059
1060MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1061MODULE_DESCRIPTION("Analog Devices AD7190, AD7192, AD7193, AD7195 ADC");
1062MODULE_LICENSE("GPL v2");
1063