xref: /linux/drivers/iio/adc/ad7192.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AD7192 and similar SPI ADC driver
4  *
5  * Copyright 2011-2015 Analog Devices Inc.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/device.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/sysfs.h>
16 #include <linux/spi/spi.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/err.h>
19 #include <linux/sched.h>
20 #include <linux/delay.h>
21 #include <linux/module.h>
22 #include <linux/mod_devicetable.h>
23 #include <linux/property.h>
24 #include <linux/units.h>
25 
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/trigger.h>
30 #include <linux/iio/trigger_consumer.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include <linux/iio/adc/ad_sigma_delta.h>
33 
34 /* Registers */
35 #define AD7192_REG_COMM		0 /* Communications Register (WO, 8-bit) */
36 #define AD7192_REG_STAT		0 /* Status Register	     (RO, 8-bit) */
37 #define AD7192_REG_MODE		1 /* Mode Register	     (RW, 24-bit */
38 #define AD7192_REG_CONF		2 /* Configuration Register  (RW, 24-bit) */
39 #define AD7192_REG_DATA		3 /* Data Register	     (RO, 24/32-bit) */
40 #define AD7192_REG_ID		4 /* ID Register	     (RO, 8-bit) */
41 #define AD7192_REG_GPOCON	5 /* GPOCON Register	     (RO, 8-bit) */
42 #define AD7192_REG_OFFSET	6 /* Offset Register	     (RW, 16-bit */
43 				  /* (AD7792)/24-bit (AD7192)) */
44 #define AD7192_REG_FULLSALE	7 /* Full-Scale Register */
45 				  /* (RW, 16-bit (AD7792)/24-bit (AD7192)) */
46 
47 /* Communications Register Bit Designations (AD7192_REG_COMM) */
48 #define AD7192_COMM_WEN		BIT(7) /* Write Enable */
49 #define AD7192_COMM_WRITE	0 /* Write Operation */
50 #define AD7192_COMM_READ	BIT(6) /* Read Operation */
51 #define AD7192_COMM_ADDR_MASK	GENMASK(5, 3) /* Register Address Mask */
52 #define AD7192_COMM_CREAD	BIT(2) /* Continuous Read of Data Register */
53 
54 /* Status Register Bit Designations (AD7192_REG_STAT) */
55 #define AD7192_STAT_RDY		BIT(7) /* Ready */
56 #define AD7192_STAT_ERR		BIT(6) /* Error (Overrange, Underrange) */
57 #define AD7192_STAT_NOREF	BIT(5) /* Error no external reference */
58 #define AD7192_STAT_PARITY	BIT(4) /* Parity */
59 #define AD7192_STAT_CH3		BIT(2) /* Channel 3 */
60 #define AD7192_STAT_CH2		BIT(1) /* Channel 2 */
61 #define AD7192_STAT_CH1		BIT(0) /* Channel 1 */
62 
63 /* Mode Register Bit Designations (AD7192_REG_MODE) */
64 #define AD7192_MODE_SEL_MASK	GENMASK(23, 21) /* Operation Mode Select Mask */
65 #define AD7192_MODE_STA_MASK	BIT(20) /* Status Register transmission Mask */
66 #define AD7192_MODE_CLKSRC_MASK	GENMASK(19, 18) /* Clock Source Select Mask */
67 #define AD7192_MODE_AVG_MASK	GENMASK(17, 16)
68 		  /* Fast Settling Filter Average Select Mask (AD7193 only) */
69 #define AD7192_MODE_SINC3	BIT(15) /* SINC3 Filter Select */
70 #define AD7192_MODE_ENPAR	BIT(13) /* Parity Enable */
71 #define AD7192_MODE_CLKDIV	BIT(12) /* Clock divide by 2 (AD7190/2 only)*/
72 #define AD7192_MODE_SCYCLE	BIT(11) /* Single cycle conversion */
73 #define AD7192_MODE_REJ60	BIT(10) /* 50/60Hz notch filter */
74 				  /* Filter Update Rate Select Mask */
75 #define AD7192_MODE_RATE_MASK	GENMASK(9, 0)
76 
77 /* Mode Register: AD7192_MODE_SEL options */
78 #define AD7192_MODE_CONT		0 /* Continuous Conversion Mode */
79 #define AD7192_MODE_SINGLE		1 /* Single Conversion Mode */
80 #define AD7192_MODE_IDLE		2 /* Idle Mode */
81 #define AD7192_MODE_PWRDN		3 /* Power-Down Mode */
82 #define AD7192_MODE_CAL_INT_ZERO	4 /* Internal Zero-Scale Calibration */
83 #define AD7192_MODE_CAL_INT_FULL	5 /* Internal Full-Scale Calibration */
84 #define AD7192_MODE_CAL_SYS_ZERO	6 /* System Zero-Scale Calibration */
85 #define AD7192_MODE_CAL_SYS_FULL	7 /* System Full-Scale Calibration */
86 
87 /* Mode Register: AD7192_MODE_CLKSRC options */
88 #define AD7192_CLK_EXT_MCLK1_2		0 /* External 4.92 MHz Clock connected*/
89 					  /* from MCLK1 to MCLK2 */
90 #define AD7192_CLK_EXT_MCLK2		1 /* External Clock applied to MCLK2 */
91 #define AD7192_CLK_INT			2 /* Internal 4.92 MHz Clock not */
92 					  /* available at the MCLK2 pin */
93 #define AD7192_CLK_INT_CO		3 /* Internal 4.92 MHz Clock available*/
94 					  /* at the MCLK2 pin */
95 
96 /* Configuration Register Bit Designations (AD7192_REG_CONF) */
97 
98 #define AD7192_CONF_CHOP	BIT(23) /* CHOP enable */
99 #define AD7192_CONF_ACX		BIT(22) /* AC excitation enable(AD7195 only) */
100 #define AD7192_CONF_REFSEL	BIT(20) /* REFIN1/REFIN2 Reference Select */
101 #define AD7192_CONF_CHAN_MASK	GENMASK(18, 8) /* Channel select mask */
102 #define AD7192_CONF_BURN	BIT(7) /* Burnout current enable */
103 #define AD7192_CONF_REFDET	BIT(6) /* Reference detect enable */
104 #define AD7192_CONF_BUF		BIT(4) /* Buffered Mode Enable */
105 #define AD7192_CONF_UNIPOLAR	BIT(3) /* Unipolar/Bipolar Enable */
106 #define AD7192_CONF_GAIN_MASK	GENMASK(2, 0) /* Gain Select */
107 
108 #define AD7192_CH_AIN1P_AIN2M	BIT(0) /* AIN1(+) - AIN2(-) */
109 #define AD7192_CH_AIN3P_AIN4M	BIT(1) /* AIN3(+) - AIN4(-) */
110 #define AD7192_CH_TEMP		BIT(2) /* Temp Sensor */
111 #define AD7192_CH_AIN2P_AIN2M	BIT(3) /* AIN2(+) - AIN2(-) */
112 #define AD7192_CH_AIN1		BIT(4) /* AIN1 - AINCOM */
113 #define AD7192_CH_AIN2		BIT(5) /* AIN2 - AINCOM */
114 #define AD7192_CH_AIN3		BIT(6) /* AIN3 - AINCOM */
115 #define AD7192_CH_AIN4		BIT(7) /* AIN4 - AINCOM */
116 
117 #define AD7193_CH_AIN1P_AIN2M	0x001  /* AIN1(+) - AIN2(-) */
118 #define AD7193_CH_AIN3P_AIN4M	0x002  /* AIN3(+) - AIN4(-) */
119 #define AD7193_CH_AIN5P_AIN6M	0x004  /* AIN5(+) - AIN6(-) */
120 #define AD7193_CH_AIN7P_AIN8M	0x008  /* AIN7(+) - AIN8(-) */
121 #define AD7193_CH_TEMP		0x100 /* Temp senseor */
122 #define AD7193_CH_AIN2P_AIN2M	0x200 /* AIN2(+) - AIN2(-) */
123 #define AD7193_CH_AIN1		0x401 /* AIN1 - AINCOM */
124 #define AD7193_CH_AIN2		0x402 /* AIN2 - AINCOM */
125 #define AD7193_CH_AIN3		0x404 /* AIN3 - AINCOM */
126 #define AD7193_CH_AIN4		0x408 /* AIN4 - AINCOM */
127 #define AD7193_CH_AIN5		0x410 /* AIN5 - AINCOM */
128 #define AD7193_CH_AIN6		0x420 /* AIN6 - AINCOM */
129 #define AD7193_CH_AIN7		0x440 /* AIN7 - AINCOM */
130 #define AD7193_CH_AIN8		0x480 /* AIN7 - AINCOM */
131 #define AD7193_CH_AINCOM	0x600 /* AINCOM - AINCOM */
132 
133 #define AD7194_CH_POS(x)	(((x) - 1) << 4)
134 #define AD7194_CH_NEG(x)	((x) - 1)
135 
136 /* 10th bit corresponds to CON18(Pseudo) */
137 #define AD7194_CH(p)		(BIT(10) | AD7194_CH_POS(p))
138 
139 #define AD7194_DIFF_CH(p, n)	(AD7194_CH_POS(p) | AD7194_CH_NEG(n))
140 #define AD7194_CH_TEMP		0x100
141 #define AD7194_CH_BASE_NR	2
142 #define AD7194_CH_AIN_START	1
143 #define AD7194_CH_AIN_NR	16
144 #define AD7194_CH_MAX_NR	272
145 
146 /* ID Register Bit Designations (AD7192_REG_ID) */
147 #define CHIPID_AD7190		0x4
148 #define CHIPID_AD7192		0x0
149 #define CHIPID_AD7193		0x2
150 #define CHIPID_AD7194		0x3
151 #define CHIPID_AD7195		0x6
152 #define AD7192_ID_MASK		GENMASK(3, 0)
153 
154 /* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
155 #define AD7192_GPOCON_BPDSW	BIT(6) /* Bridge power-down switch enable */
156 #define AD7192_GPOCON_GP32EN	BIT(5) /* Digital Output P3 and P2 enable */
157 #define AD7192_GPOCON_GP10EN	BIT(4) /* Digital Output P1 and P0 enable */
158 #define AD7192_GPOCON_P3DAT	BIT(3) /* P3 state */
159 #define AD7192_GPOCON_P2DAT	BIT(2) /* P2 state */
160 #define AD7192_GPOCON_P1DAT	BIT(1) /* P1 state */
161 #define AD7192_GPOCON_P0DAT	BIT(0) /* P0 state */
162 
163 #define AD7192_EXT_FREQ_MHZ_MIN	2457600
164 #define AD7192_EXT_FREQ_MHZ_MAX	5120000
165 #define AD7192_INT_FREQ_MHZ	4915200
166 
167 #define AD7192_NO_SYNC_FILTER	1
168 #define AD7192_SYNC3_FILTER	3
169 #define AD7192_SYNC4_FILTER	4
170 
171 /* NOTE:
172  * The AD7190/2/5 features a dual use data out ready DOUT/RDY output.
173  * In order to avoid contentions on the SPI bus, it's therefore necessary
174  * to use spi bus locking.
175  *
176  * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
177  */
178 
179 enum {
180 	AD7192_SYSCALIB_ZERO_SCALE,
181 	AD7192_SYSCALIB_FULL_SCALE,
182 };
183 
184 enum {
185 	ID_AD7190,
186 	ID_AD7192,
187 	ID_AD7193,
188 	ID_AD7194,
189 	ID_AD7195,
190 };
191 
192 struct ad7192_chip_info {
193 	unsigned int			chip_id;
194 	const char			*name;
195 	const struct iio_chan_spec	*channels;
196 	u8				num_channels;
197 	const struct ad_sigma_delta_info	*sigma_delta_info;
198 	const struct iio_info		*info;
199 	int (*parse_channels)(struct iio_dev *indio_dev);
200 };
201 
202 struct ad7192_state {
203 	const struct ad7192_chip_info	*chip_info;
204 	struct clk			*mclk;
205 	struct clk_hw			int_clk_hw;
206 	u16				int_vref_mv;
207 	u32				aincom_mv;
208 	u32				fclk;
209 	u32				mode;
210 	u32				conf;
211 	u32				scale_avail[8][2];
212 	u32				filter_freq_avail[4][2];
213 	u32				oversampling_ratio_avail[4];
214 	u8				gpocon;
215 	u8				clock_sel;
216 	struct mutex			lock;	/* protect sensor state */
217 	u8				syscalib_mode[8];
218 
219 	struct ad_sigma_delta		sd;
220 };
221 
222 static const char * const ad7192_syscalib_modes[] = {
223 	[AD7192_SYSCALIB_ZERO_SCALE] = "zero_scale",
224 	[AD7192_SYSCALIB_FULL_SCALE] = "full_scale",
225 };
226 
ad7192_set_syscalib_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)227 static int ad7192_set_syscalib_mode(struct iio_dev *indio_dev,
228 				    const struct iio_chan_spec *chan,
229 				    unsigned int mode)
230 {
231 	struct ad7192_state *st = iio_priv(indio_dev);
232 
233 	st->syscalib_mode[chan->channel] = mode;
234 
235 	return 0;
236 }
237 
ad7192_get_syscalib_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)238 static int ad7192_get_syscalib_mode(struct iio_dev *indio_dev,
239 				    const struct iio_chan_spec *chan)
240 {
241 	struct ad7192_state *st = iio_priv(indio_dev);
242 
243 	return st->syscalib_mode[chan->channel];
244 }
245 
ad7192_write_syscalib(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)246 static ssize_t ad7192_write_syscalib(struct iio_dev *indio_dev,
247 				     uintptr_t private,
248 				     const struct iio_chan_spec *chan,
249 				     const char *buf, size_t len)
250 {
251 	struct ad7192_state *st = iio_priv(indio_dev);
252 	bool sys_calib;
253 	int ret, temp;
254 
255 	ret = kstrtobool(buf, &sys_calib);
256 	if (ret)
257 		return ret;
258 
259 	temp = st->syscalib_mode[chan->channel];
260 	if (sys_calib) {
261 		if (temp == AD7192_SYSCALIB_ZERO_SCALE)
262 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_ZERO,
263 					      chan->address);
264 		else
265 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_FULL,
266 					      chan->address);
267 	}
268 
269 	return ret ? ret : len;
270 }
271 
272 static const struct iio_enum ad7192_syscalib_mode_enum = {
273 	.items = ad7192_syscalib_modes,
274 	.num_items = ARRAY_SIZE(ad7192_syscalib_modes),
275 	.set = ad7192_set_syscalib_mode,
276 	.get = ad7192_get_syscalib_mode
277 };
278 
279 static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = {
280 	{
281 		.name = "sys_calibration",
282 		.write = ad7192_write_syscalib,
283 		.shared = IIO_SEPARATE,
284 	},
285 	IIO_ENUM("sys_calibration_mode", IIO_SEPARATE,
286 		 &ad7192_syscalib_mode_enum),
287 	IIO_ENUM_AVAILABLE("sys_calibration_mode", IIO_SHARED_BY_TYPE,
288 			   &ad7192_syscalib_mode_enum),
289 	{ }
290 };
291 
ad_sigma_delta_to_ad7192(struct ad_sigma_delta * sd)292 static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd)
293 {
294 	return container_of(sd, struct ad7192_state, sd);
295 }
296 
ad7192_set_channel(struct ad_sigma_delta * sd,unsigned int channel)297 static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
298 {
299 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
300 
301 	st->conf &= ~AD7192_CONF_CHAN_MASK;
302 	st->conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, channel);
303 
304 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
305 }
306 
ad7192_set_mode(struct ad_sigma_delta * sd,enum ad_sigma_delta_mode mode)307 static int ad7192_set_mode(struct ad_sigma_delta *sd,
308 			   enum ad_sigma_delta_mode mode)
309 {
310 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
311 
312 	st->mode &= ~AD7192_MODE_SEL_MASK;
313 	st->mode |= FIELD_PREP(AD7192_MODE_SEL_MASK, mode);
314 
315 	return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
316 }
317 
ad7192_append_status(struct ad_sigma_delta * sd,bool append)318 static int ad7192_append_status(struct ad_sigma_delta *sd, bool append)
319 {
320 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
321 	unsigned int mode = st->mode;
322 	int ret;
323 
324 	mode &= ~AD7192_MODE_STA_MASK;
325 	mode |= FIELD_PREP(AD7192_MODE_STA_MASK, append);
326 
327 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, mode);
328 	if (ret < 0)
329 		return ret;
330 
331 	st->mode = mode;
332 
333 	return 0;
334 }
335 
ad7192_disable_all(struct ad_sigma_delta * sd)336 static int ad7192_disable_all(struct ad_sigma_delta *sd)
337 {
338 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
339 	u32 conf = st->conf;
340 	int ret;
341 
342 	conf &= ~AD7192_CONF_CHAN_MASK;
343 
344 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
345 	if (ret < 0)
346 		return ret;
347 
348 	st->conf = conf;
349 
350 	return 0;
351 }
352 
353 static const struct ad_sigma_delta_info ad7192_sigma_delta_info = {
354 	.set_channel = ad7192_set_channel,
355 	.append_status = ad7192_append_status,
356 	.disable_all = ad7192_disable_all,
357 	.set_mode = ad7192_set_mode,
358 	.has_registers = true,
359 	.addr_shift = 3,
360 	.read_mask = BIT(6),
361 	.status_ch_mask = GENMASK(3, 0),
362 	.num_slots = 4,
363 	.irq_flags = IRQF_TRIGGER_FALLING,
364 };
365 
366 static const struct ad_sigma_delta_info ad7194_sigma_delta_info = {
367 	.set_channel = ad7192_set_channel,
368 	.append_status = ad7192_append_status,
369 	.disable_all = ad7192_disable_all,
370 	.set_mode = ad7192_set_mode,
371 	.has_registers = true,
372 	.addr_shift = 3,
373 	.read_mask = BIT(6),
374 	.status_ch_mask = GENMASK(3, 0),
375 	.irq_flags = IRQF_TRIGGER_FALLING,
376 };
377 
378 static const struct ad_sd_calib_data ad7192_calib_arr[8] = {
379 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
380 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
381 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
382 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
383 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
384 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
385 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
386 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
387 };
388 
ad7192_calibrate_all(struct ad7192_state * st)389 static int ad7192_calibrate_all(struct ad7192_state *st)
390 {
391 	return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr,
392 				   ARRAY_SIZE(ad7192_calib_arr));
393 }
394 
ad7192_valid_external_frequency(u32 freq)395 static inline bool ad7192_valid_external_frequency(u32 freq)
396 {
397 	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
398 		freq <= AD7192_EXT_FREQ_MHZ_MAX);
399 }
400 
401 /*
402  * Position 0 of ad7192_clock_names, xtal, corresponds to clock source
403  * configuration AD7192_CLK_EXT_MCLK1_2 and position 1, mclk, corresponds to
404  * AD7192_CLK_EXT_MCLK2
405  */
406 static const char *const ad7192_clock_names[] = {
407 	"xtal",
408 	"mclk"
409 };
410 
clk_hw_to_ad7192(struct clk_hw * hw)411 static struct ad7192_state *clk_hw_to_ad7192(struct clk_hw *hw)
412 {
413 	return container_of(hw, struct ad7192_state, int_clk_hw);
414 }
415 
ad7192_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)416 static unsigned long ad7192_clk_recalc_rate(struct clk_hw *hw,
417 					    unsigned long parent_rate)
418 {
419 	return AD7192_INT_FREQ_MHZ;
420 }
421 
ad7192_clk_output_is_enabled(struct clk_hw * hw)422 static int ad7192_clk_output_is_enabled(struct clk_hw *hw)
423 {
424 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
425 
426 	return st->clock_sel == AD7192_CLK_INT_CO;
427 }
428 
ad7192_clk_prepare(struct clk_hw * hw)429 static int ad7192_clk_prepare(struct clk_hw *hw)
430 {
431 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
432 	int ret;
433 
434 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
435 	st->mode |= AD7192_CLK_INT_CO;
436 
437 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
438 	if (ret)
439 		return ret;
440 
441 	st->clock_sel = AD7192_CLK_INT_CO;
442 
443 	return 0;
444 }
445 
ad7192_clk_unprepare(struct clk_hw * hw)446 static void ad7192_clk_unprepare(struct clk_hw *hw)
447 {
448 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
449 	int ret;
450 
451 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
452 	st->mode |= AD7192_CLK_INT;
453 
454 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
455 	if (ret)
456 		return;
457 
458 	st->clock_sel = AD7192_CLK_INT;
459 }
460 
461 static const struct clk_ops ad7192_int_clk_ops = {
462 	.recalc_rate = ad7192_clk_recalc_rate,
463 	.is_enabled = ad7192_clk_output_is_enabled,
464 	.prepare = ad7192_clk_prepare,
465 	.unprepare = ad7192_clk_unprepare,
466 };
467 
ad7192_register_clk_provider(struct ad7192_state * st)468 static int ad7192_register_clk_provider(struct ad7192_state *st)
469 {
470 	struct device *dev = &st->sd.spi->dev;
471 	struct clk_init_data init = {};
472 	int ret;
473 
474 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
475 		return 0;
476 
477 	if (!device_property_present(dev, "#clock-cells"))
478 		return 0;
479 
480 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk",
481 				   fwnode_get_name(dev_fwnode(dev)));
482 	if (!init.name)
483 		return -ENOMEM;
484 
485 	init.ops = &ad7192_int_clk_ops;
486 
487 	st->int_clk_hw.init = &init;
488 	ret = devm_clk_hw_register(dev, &st->int_clk_hw);
489 	if (ret)
490 		return ret;
491 
492 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
493 					   &st->int_clk_hw);
494 }
495 
ad7192_clock_setup(struct ad7192_state * st)496 static int ad7192_clock_setup(struct ad7192_state *st)
497 {
498 	struct device *dev = &st->sd.spi->dev;
499 	int ret;
500 
501 	/*
502 	 * The following two if branches are kept for backward compatibility but
503 	 * the use of the two devicetree properties is highly discouraged. Clock
504 	 * configuration should be done according to the bindings.
505 	 */
506 
507 	if (device_property_read_bool(dev, "adi,int-clock-output-enable")) {
508 		st->clock_sel = AD7192_CLK_INT_CO;
509 		st->fclk = AD7192_INT_FREQ_MHZ;
510 		dev_warn(dev, "Property adi,int-clock-output-enable is deprecated! Check bindings!\n");
511 		return 0;
512 	}
513 
514 	if (device_property_read_bool(dev, "adi,clock-xtal")) {
515 		st->clock_sel = AD7192_CLK_EXT_MCLK1_2;
516 		st->mclk = devm_clk_get_enabled(dev, "mclk");
517 		if (IS_ERR(st->mclk))
518 			return dev_err_probe(dev, PTR_ERR(st->mclk),
519 					     "Failed to get mclk\n");
520 
521 		st->fclk = clk_get_rate(st->mclk);
522 		if (!ad7192_valid_external_frequency(st->fclk))
523 			return dev_err_probe(dev, -EINVAL,
524 					     "External clock frequency out of bounds\n");
525 
526 		dev_warn(dev, "Property adi,clock-xtal is deprecated! Check bindings!\n");
527 		return 0;
528 	}
529 
530 	ret = device_property_match_property_string(dev, "clock-names",
531 						    ad7192_clock_names,
532 						    ARRAY_SIZE(ad7192_clock_names));
533 	if (ret < 0) {
534 		st->clock_sel = AD7192_CLK_INT;
535 		st->fclk = AD7192_INT_FREQ_MHZ;
536 
537 		ret = ad7192_register_clk_provider(st);
538 		if (ret)
539 			return dev_err_probe(dev, ret,
540 					     "Failed to register clock provider\n");
541 		return 0;
542 	}
543 
544 	st->clock_sel = AD7192_CLK_EXT_MCLK1_2 + ret;
545 
546 	st->mclk = devm_clk_get_enabled(dev, ad7192_clock_names[ret]);
547 	if (IS_ERR(st->mclk))
548 		return dev_err_probe(dev, PTR_ERR(st->mclk),
549 				     "Failed to get clock source\n");
550 
551 	st->fclk = clk_get_rate(st->mclk);
552 	if (!ad7192_valid_external_frequency(st->fclk))
553 		return dev_err_probe(dev, -EINVAL,
554 				     "External clock frequency out of bounds\n");
555 
556 	return 0;
557 }
558 
ad7192_setup(struct iio_dev * indio_dev,struct device * dev)559 static int ad7192_setup(struct iio_dev *indio_dev, struct device *dev)
560 {
561 	struct ad7192_state *st = iio_priv(indio_dev);
562 	bool rej60_en, refin2_en;
563 	bool buf_en, bipolar, burnout_curr_en;
564 	unsigned long long scale_uv;
565 	int i, ret, id;
566 
567 	/* reset the serial interface */
568 	ret = ad_sd_reset(&st->sd, 48);
569 	if (ret < 0)
570 		return ret;
571 	usleep_range(500, 1000); /* Wait for at least 500us */
572 
573 	/* write/read test for device presence */
574 	ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id);
575 	if (ret)
576 		return ret;
577 
578 	id = FIELD_GET(AD7192_ID_MASK, id);
579 
580 	if (id != st->chip_info->chip_id)
581 		dev_warn(dev, "device ID query failed (0x%X != 0x%X)\n",
582 			 id, st->chip_info->chip_id);
583 
584 	st->mode = FIELD_PREP(AD7192_MODE_SEL_MASK, AD7192_MODE_IDLE) |
585 		FIELD_PREP(AD7192_MODE_CLKSRC_MASK, st->clock_sel) |
586 		FIELD_PREP(AD7192_MODE_RATE_MASK, 480);
587 
588 	st->conf = FIELD_PREP(AD7192_CONF_GAIN_MASK, 0);
589 
590 	rej60_en = device_property_read_bool(dev, "adi,rejection-60-Hz-enable");
591 	if (rej60_en)
592 		st->mode |= AD7192_MODE_REJ60;
593 
594 	refin2_en = device_property_read_bool(dev, "adi,refin2-pins-enable");
595 	if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195)
596 		st->conf |= AD7192_CONF_REFSEL;
597 
598 	st->conf &= ~AD7192_CONF_CHOP;
599 
600 	buf_en = device_property_read_bool(dev, "adi,buffer-enable");
601 	if (buf_en)
602 		st->conf |= AD7192_CONF_BUF;
603 
604 	bipolar = device_property_read_bool(dev, "bipolar");
605 	if (!bipolar)
606 		st->conf |= AD7192_CONF_UNIPOLAR;
607 
608 	burnout_curr_en = device_property_read_bool(dev,
609 						    "adi,burnout-currents-enable");
610 	if (burnout_curr_en && buf_en) {
611 		st->conf |= AD7192_CONF_BURN;
612 	} else if (burnout_curr_en) {
613 		dev_warn(dev,
614 			 "Can't enable burnout currents: see CHOP or buffer\n");
615 	}
616 
617 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
618 	if (ret)
619 		return ret;
620 
621 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
622 	if (ret)
623 		return ret;
624 
625 	ret = ad7192_calibrate_all(st);
626 	if (ret)
627 		return ret;
628 
629 	/* Populate available ADC input ranges */
630 	for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
631 		scale_uv = ((u64)st->int_vref_mv * 100000000)
632 			>> (indio_dev->channels[0].scan_type.realbits -
633 			!FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf));
634 		scale_uv >>= i;
635 
636 		st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
637 		st->scale_avail[i][0] = scale_uv;
638 	}
639 
640 	st->oversampling_ratio_avail[0] = 1;
641 	st->oversampling_ratio_avail[1] = 2;
642 	st->oversampling_ratio_avail[2] = 8;
643 	st->oversampling_ratio_avail[3] = 16;
644 
645 	st->filter_freq_avail[0][0] = 600;
646 	st->filter_freq_avail[1][0] = 800;
647 	st->filter_freq_avail[2][0] = 2300;
648 	st->filter_freq_avail[3][0] = 2720;
649 
650 	st->filter_freq_avail[0][1] = 1000;
651 	st->filter_freq_avail[1][1] = 1000;
652 	st->filter_freq_avail[2][1] = 1000;
653 	st->filter_freq_avail[3][1] = 1000;
654 
655 	return 0;
656 }
657 
ad7192_show_ac_excitation(struct device * dev,struct device_attribute * attr,char * buf)658 static ssize_t ad7192_show_ac_excitation(struct device *dev,
659 					 struct device_attribute *attr,
660 					 char *buf)
661 {
662 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
663 	struct ad7192_state *st = iio_priv(indio_dev);
664 
665 	return sysfs_emit(buf, "%ld\n", FIELD_GET(AD7192_CONF_ACX, st->conf));
666 }
667 
ad7192_show_bridge_switch(struct device * dev,struct device_attribute * attr,char * buf)668 static ssize_t ad7192_show_bridge_switch(struct device *dev,
669 					 struct device_attribute *attr,
670 					 char *buf)
671 {
672 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
673 	struct ad7192_state *st = iio_priv(indio_dev);
674 
675 	return sysfs_emit(buf, "%ld\n",
676 			  FIELD_GET(AD7192_GPOCON_BPDSW, st->gpocon));
677 }
678 
ad7192_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)679 static ssize_t ad7192_set(struct device *dev,
680 			  struct device_attribute *attr,
681 			  const char *buf,
682 			  size_t len)
683 {
684 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
685 	struct ad7192_state *st = iio_priv(indio_dev);
686 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
687 	int ret;
688 	bool val;
689 
690 	ret = kstrtobool(buf, &val);
691 	if (ret < 0)
692 		return ret;
693 
694 	ret = iio_device_claim_direct_mode(indio_dev);
695 	if (ret)
696 		return ret;
697 
698 	switch ((u32)this_attr->address) {
699 	case AD7192_REG_GPOCON:
700 		if (val)
701 			st->gpocon |= AD7192_GPOCON_BPDSW;
702 		else
703 			st->gpocon &= ~AD7192_GPOCON_BPDSW;
704 
705 		ad_sd_write_reg(&st->sd, AD7192_REG_GPOCON, 1, st->gpocon);
706 		break;
707 	case AD7192_REG_CONF:
708 		if (val)
709 			st->conf |= AD7192_CONF_ACX;
710 		else
711 			st->conf &= ~AD7192_CONF_ACX;
712 
713 		ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
714 		break;
715 	default:
716 		ret = -EINVAL;
717 	}
718 
719 	iio_device_release_direct_mode(indio_dev);
720 
721 	return ret ? ret : len;
722 }
723 
ad7192_compute_f_order(struct ad7192_state * st,bool sinc3_en,bool chop_en)724 static int ad7192_compute_f_order(struct ad7192_state *st, bool sinc3_en, bool chop_en)
725 {
726 	u8 avg_factor_selected, oversampling_ratio;
727 
728 	avg_factor_selected = FIELD_GET(AD7192_MODE_AVG_MASK, st->mode);
729 
730 	if (!avg_factor_selected && !chop_en)
731 		return 1;
732 
733 	oversampling_ratio = st->oversampling_ratio_avail[avg_factor_selected];
734 
735 	if (sinc3_en)
736 		return AD7192_SYNC3_FILTER + oversampling_ratio - 1;
737 
738 	return AD7192_SYNC4_FILTER + oversampling_ratio - 1;
739 }
740 
ad7192_get_f_order(struct ad7192_state * st)741 static int ad7192_get_f_order(struct ad7192_state *st)
742 {
743 	bool sinc3_en, chop_en;
744 
745 	sinc3_en = FIELD_GET(AD7192_MODE_SINC3, st->mode);
746 	chop_en = FIELD_GET(AD7192_CONF_CHOP, st->conf);
747 
748 	return ad7192_compute_f_order(st, sinc3_en, chop_en);
749 }
750 
ad7192_compute_f_adc(struct ad7192_state * st,bool sinc3_en,bool chop_en)751 static int ad7192_compute_f_adc(struct ad7192_state *st, bool sinc3_en,
752 				bool chop_en)
753 {
754 	unsigned int f_order = ad7192_compute_f_order(st, sinc3_en, chop_en);
755 
756 	return DIV_ROUND_CLOSEST(st->fclk,
757 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
758 }
759 
ad7192_get_f_adc(struct ad7192_state * st)760 static int ad7192_get_f_adc(struct ad7192_state *st)
761 {
762 	unsigned int f_order = ad7192_get_f_order(st);
763 
764 	return DIV_ROUND_CLOSEST(st->fclk,
765 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
766 }
767 
ad7192_update_filter_freq_avail(struct ad7192_state * st)768 static void ad7192_update_filter_freq_avail(struct ad7192_state *st)
769 {
770 	unsigned int fadc;
771 
772 	/* Formulas for filter at page 25 of the datasheet */
773 	fadc = ad7192_compute_f_adc(st, false, true);
774 	st->filter_freq_avail[0][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
775 
776 	fadc = ad7192_compute_f_adc(st, true, true);
777 	st->filter_freq_avail[1][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
778 
779 	fadc = ad7192_compute_f_adc(st, false, false);
780 	st->filter_freq_avail[2][0] = DIV_ROUND_CLOSEST(fadc * 230, 1024);
781 
782 	fadc = ad7192_compute_f_adc(st, true, false);
783 	st->filter_freq_avail[3][0] = DIV_ROUND_CLOSEST(fadc * 272, 1024);
784 }
785 
786 static IIO_DEVICE_ATTR(bridge_switch_en, 0644,
787 		       ad7192_show_bridge_switch, ad7192_set,
788 		       AD7192_REG_GPOCON);
789 
790 static IIO_DEVICE_ATTR(ac_excitation_en, 0644,
791 		       ad7192_show_ac_excitation, ad7192_set,
792 		       AD7192_REG_CONF);
793 
794 static struct attribute *ad7192_attributes[] = {
795 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
796 	NULL
797 };
798 
799 static const struct attribute_group ad7192_attribute_group = {
800 	.attrs = ad7192_attributes,
801 };
802 
803 static struct attribute *ad7195_attributes[] = {
804 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
805 	&iio_dev_attr_ac_excitation_en.dev_attr.attr,
806 	NULL
807 };
808 
809 static const struct attribute_group ad7195_attribute_group = {
810 	.attrs = ad7195_attributes,
811 };
812 
ad7192_get_temp_scale(bool unipolar)813 static unsigned int ad7192_get_temp_scale(bool unipolar)
814 {
815 	return unipolar ? 2815 * 2 : 2815;
816 }
817 
ad7192_set_3db_filter_freq(struct ad7192_state * st,int val,int val2)818 static int ad7192_set_3db_filter_freq(struct ad7192_state *st,
819 				      int val, int val2)
820 {
821 	int i, ret, freq;
822 	unsigned int diff_new, diff_old;
823 	int idx = 0;
824 
825 	diff_old = U32_MAX;
826 	freq = val * 1000 + val2;
827 
828 	for (i = 0; i < ARRAY_SIZE(st->filter_freq_avail); i++) {
829 		diff_new = abs(freq - st->filter_freq_avail[i][0]);
830 		if (diff_new < diff_old) {
831 			diff_old = diff_new;
832 			idx = i;
833 		}
834 	}
835 
836 	switch (idx) {
837 	case 0:
838 		st->mode &= ~AD7192_MODE_SINC3;
839 
840 		st->conf |= AD7192_CONF_CHOP;
841 		break;
842 	case 1:
843 		st->mode |= AD7192_MODE_SINC3;
844 
845 		st->conf |= AD7192_CONF_CHOP;
846 		break;
847 	case 2:
848 		st->mode &= ~AD7192_MODE_SINC3;
849 
850 		st->conf &= ~AD7192_CONF_CHOP;
851 		break;
852 	case 3:
853 		st->mode |= AD7192_MODE_SINC3;
854 
855 		st->conf &= ~AD7192_CONF_CHOP;
856 		break;
857 	}
858 
859 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
860 	if (ret < 0)
861 		return ret;
862 
863 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
864 }
865 
ad7192_get_3db_filter_freq(struct ad7192_state * st)866 static int ad7192_get_3db_filter_freq(struct ad7192_state *st)
867 {
868 	unsigned int fadc;
869 
870 	fadc = ad7192_get_f_adc(st);
871 
872 	if (FIELD_GET(AD7192_CONF_CHOP, st->conf))
873 		return DIV_ROUND_CLOSEST(fadc * 240, 1024);
874 	if (FIELD_GET(AD7192_MODE_SINC3, st->mode))
875 		return DIV_ROUND_CLOSEST(fadc * 272, 1024);
876 	else
877 		return DIV_ROUND_CLOSEST(fadc * 230, 1024);
878 }
879 
ad7192_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)880 static int ad7192_read_raw(struct iio_dev *indio_dev,
881 			   struct iio_chan_spec const *chan,
882 			   int *val,
883 			   int *val2,
884 			   long m)
885 {
886 	struct ad7192_state *st = iio_priv(indio_dev);
887 	bool unipolar = FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf);
888 	u8 gain = FIELD_GET(AD7192_CONF_GAIN_MASK, st->conf);
889 
890 	switch (m) {
891 	case IIO_CHAN_INFO_RAW:
892 		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
893 	case IIO_CHAN_INFO_SCALE:
894 		switch (chan->type) {
895 		case IIO_VOLTAGE:
896 			mutex_lock(&st->lock);
897 			*val = st->scale_avail[gain][0];
898 			*val2 = st->scale_avail[gain][1];
899 			mutex_unlock(&st->lock);
900 			return IIO_VAL_INT_PLUS_NANO;
901 		case IIO_TEMP:
902 			*val = 0;
903 			*val2 = 1000000000 / ad7192_get_temp_scale(unipolar);
904 			return IIO_VAL_INT_PLUS_NANO;
905 		default:
906 			return -EINVAL;
907 		}
908 	case IIO_CHAN_INFO_OFFSET:
909 		if (!unipolar)
910 			*val = -(1 << (chan->scan_type.realbits - 1));
911 		else
912 			*val = 0;
913 
914 		switch (chan->type) {
915 		case IIO_VOLTAGE:
916 			/*
917 			 * Only applies to pseudo-differential inputs.
918 			 * AINCOM voltage has to be converted to "raw" units.
919 			 */
920 			if (st->aincom_mv && !chan->differential)
921 				*val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * NANO,
922 							      st->scale_avail[gain][1]);
923 			return IIO_VAL_INT;
924 		/* Kelvin to Celsius */
925 		case IIO_TEMP:
926 			*val -= 273 * ad7192_get_temp_scale(unipolar);
927 			return IIO_VAL_INT;
928 		default:
929 			return -EINVAL;
930 		}
931 	case IIO_CHAN_INFO_SAMP_FREQ:
932 		*val = DIV_ROUND_CLOSEST(ad7192_get_f_adc(st), 1024);
933 		return IIO_VAL_INT;
934 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
935 		*val = ad7192_get_3db_filter_freq(st);
936 		*val2 = 1000;
937 		return IIO_VAL_FRACTIONAL;
938 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
939 		*val = st->oversampling_ratio_avail[FIELD_GET(AD7192_MODE_AVG_MASK, st->mode)];
940 		return IIO_VAL_INT;
941 	}
942 
943 	return -EINVAL;
944 }
945 
ad7192_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)946 static int ad7192_write_raw(struct iio_dev *indio_dev,
947 			    struct iio_chan_spec const *chan,
948 			    int val,
949 			    int val2,
950 			    long mask)
951 {
952 	struct ad7192_state *st = iio_priv(indio_dev);
953 	int ret, i, div;
954 	unsigned int tmp;
955 
956 	ret = iio_device_claim_direct_mode(indio_dev);
957 	if (ret)
958 		return ret;
959 
960 	mutex_lock(&st->lock);
961 
962 	switch (mask) {
963 	case IIO_CHAN_INFO_SCALE:
964 		ret = -EINVAL;
965 		for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
966 			if (val2 == st->scale_avail[i][1]) {
967 				ret = 0;
968 				tmp = st->conf;
969 				st->conf &= ~AD7192_CONF_GAIN_MASK;
970 				st->conf |= FIELD_PREP(AD7192_CONF_GAIN_MASK, i);
971 				if (tmp == st->conf)
972 					break;
973 				ad_sd_write_reg(&st->sd, AD7192_REG_CONF,
974 						3, st->conf);
975 				ad7192_calibrate_all(st);
976 				break;
977 			}
978 		break;
979 	case IIO_CHAN_INFO_SAMP_FREQ:
980 		if (!val) {
981 			ret = -EINVAL;
982 			break;
983 		}
984 
985 		div = st->fclk / (val * ad7192_get_f_order(st) * 1024);
986 		if (div < 1 || div > 1023) {
987 			ret = -EINVAL;
988 			break;
989 		}
990 
991 		st->mode &= ~AD7192_MODE_RATE_MASK;
992 		st->mode |= FIELD_PREP(AD7192_MODE_RATE_MASK, div);
993 		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
994 		ad7192_update_filter_freq_avail(st);
995 		break;
996 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
997 		ret = ad7192_set_3db_filter_freq(st, val, val2 / 1000);
998 		break;
999 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1000 		ret = -EINVAL;
1001 		for (i = 0; i < ARRAY_SIZE(st->oversampling_ratio_avail); i++)
1002 			if (val == st->oversampling_ratio_avail[i]) {
1003 				ret = 0;
1004 				tmp = st->mode;
1005 				st->mode &= ~AD7192_MODE_AVG_MASK;
1006 				st->mode |= FIELD_PREP(AD7192_MODE_AVG_MASK, i);
1007 				if (tmp == st->mode)
1008 					break;
1009 				ad_sd_write_reg(&st->sd, AD7192_REG_MODE,
1010 						3, st->mode);
1011 				break;
1012 			}
1013 		ad7192_update_filter_freq_avail(st);
1014 		break;
1015 	default:
1016 		ret = -EINVAL;
1017 	}
1018 
1019 	mutex_unlock(&st->lock);
1020 
1021 	iio_device_release_direct_mode(indio_dev);
1022 
1023 	return ret;
1024 }
1025 
ad7192_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)1026 static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
1027 				    struct iio_chan_spec const *chan,
1028 				    long mask)
1029 {
1030 	switch (mask) {
1031 	case IIO_CHAN_INFO_SCALE:
1032 		return IIO_VAL_INT_PLUS_NANO;
1033 	case IIO_CHAN_INFO_SAMP_FREQ:
1034 		return IIO_VAL_INT;
1035 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1036 		return IIO_VAL_INT_PLUS_MICRO;
1037 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1038 		return IIO_VAL_INT;
1039 	default:
1040 		return -EINVAL;
1041 	}
1042 }
1043 
ad7192_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)1044 static int ad7192_read_avail(struct iio_dev *indio_dev,
1045 			     struct iio_chan_spec const *chan,
1046 			     const int **vals, int *type, int *length,
1047 			     long mask)
1048 {
1049 	struct ad7192_state *st = iio_priv(indio_dev);
1050 
1051 	switch (mask) {
1052 	case IIO_CHAN_INFO_SCALE:
1053 		*vals = (int *)st->scale_avail;
1054 		*type = IIO_VAL_INT_PLUS_NANO;
1055 		/* Values are stored in a 2D matrix  */
1056 		*length = ARRAY_SIZE(st->scale_avail) * 2;
1057 
1058 		return IIO_AVAIL_LIST;
1059 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1060 		*vals = (int *)st->filter_freq_avail;
1061 		*type = IIO_VAL_FRACTIONAL;
1062 		*length = ARRAY_SIZE(st->filter_freq_avail) * 2;
1063 
1064 		return IIO_AVAIL_LIST;
1065 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1066 		*vals = (int *)st->oversampling_ratio_avail;
1067 		*type = IIO_VAL_INT;
1068 		*length = ARRAY_SIZE(st->oversampling_ratio_avail);
1069 
1070 		return IIO_AVAIL_LIST;
1071 	}
1072 
1073 	return -EINVAL;
1074 }
1075 
ad7192_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)1076 static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask)
1077 {
1078 	struct ad7192_state *st = iio_priv(indio_dev);
1079 	u32 conf = st->conf;
1080 	int ret;
1081 	int i;
1082 
1083 	conf &= ~AD7192_CONF_CHAN_MASK;
1084 	for_each_set_bit(i, scan_mask, 8)
1085 		conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, i);
1086 
1087 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
1088 	if (ret < 0)
1089 		return ret;
1090 
1091 	st->conf = conf;
1092 
1093 	return 0;
1094 }
1095 
1096 static const struct iio_info ad7192_info = {
1097 	.read_raw = ad7192_read_raw,
1098 	.write_raw = ad7192_write_raw,
1099 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1100 	.read_avail = ad7192_read_avail,
1101 	.attrs = &ad7192_attribute_group,
1102 	.validate_trigger = ad_sd_validate_trigger,
1103 	.update_scan_mode = ad7192_update_scan_mode,
1104 };
1105 
1106 static const struct iio_info ad7194_info = {
1107 	.read_raw = ad7192_read_raw,
1108 	.write_raw = ad7192_write_raw,
1109 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1110 	.read_avail = ad7192_read_avail,
1111 	.validate_trigger = ad_sd_validate_trigger,
1112 };
1113 
1114 static const struct iio_info ad7195_info = {
1115 	.read_raw = ad7192_read_raw,
1116 	.write_raw = ad7192_write_raw,
1117 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1118 	.read_avail = ad7192_read_avail,
1119 	.attrs = &ad7195_attribute_group,
1120 	.validate_trigger = ad_sd_validate_trigger,
1121 	.update_scan_mode = ad7192_update_scan_mode,
1122 };
1123 
1124 #define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _type, \
1125 	_mask_all, _mask_type_av, _mask_all_av, _ext_info) \
1126 	{ \
1127 		.type = (_type), \
1128 		.differential = ((_channel2) == -1 ? 0 : 1), \
1129 		.indexed = 1, \
1130 		.channel = (_channel1), \
1131 		.channel2 = (_channel2), \
1132 		.address = (_address), \
1133 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1134 			BIT(IIO_CHAN_INFO_OFFSET), \
1135 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
1136 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
1137 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1138 			(_mask_all), \
1139 		.info_mask_shared_by_type_available = (_mask_type_av), \
1140 		.info_mask_shared_by_all_available = \
1141 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1142 			(_mask_all_av), \
1143 		.ext_info = (_ext_info), \
1144 		.scan_index = (_si), \
1145 		.scan_type = { \
1146 			.sign = 'u', \
1147 			.realbits = 24, \
1148 			.storagebits = 32, \
1149 			.endianness = IIO_BE, \
1150 		}, \
1151 	}
1152 
1153 #define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1154 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, IIO_VOLTAGE, 0, \
1155 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1156 
1157 #define AD719x_CHANNEL(_si, _channel1, _address) \
1158 	__AD719x_CHANNEL(_si, _channel1, -1, _address, IIO_VOLTAGE, 0, \
1159 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1160 
1161 #define AD719x_TEMP_CHANNEL(_si, _address) \
1162 	__AD719x_CHANNEL(_si, 0, -1, _address, IIO_TEMP, 0, 0, 0, NULL)
1163 
1164 #define AD7193_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1165 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, \
1166 		IIO_VOLTAGE, \
1167 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1168 		BIT(IIO_CHAN_INFO_SCALE), \
1169 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1170 		ad7192_calibsys_ext_info)
1171 
1172 #define AD7193_CHANNEL(_si, _channel1, _address) \
1173 	AD7193_DIFF_CHANNEL(_si, _channel1, -1, _address)
1174 
1175 static const struct iio_chan_spec ad7192_channels[] = {
1176 	AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
1177 	AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
1178 	AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
1179 	AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M),
1180 	AD719x_CHANNEL(4, 1, AD7192_CH_AIN1),
1181 	AD719x_CHANNEL(5, 2, AD7192_CH_AIN2),
1182 	AD719x_CHANNEL(6, 3, AD7192_CH_AIN3),
1183 	AD719x_CHANNEL(7, 4, AD7192_CH_AIN4),
1184 	IIO_CHAN_SOFT_TIMESTAMP(8),
1185 };
1186 
1187 static const struct iio_chan_spec ad7193_channels[] = {
1188 	AD7193_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
1189 	AD7193_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
1190 	AD7193_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
1191 	AD7193_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M),
1192 	AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP),
1193 	AD7193_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M),
1194 	AD7193_CHANNEL(6, 1, AD7193_CH_AIN1),
1195 	AD7193_CHANNEL(7, 2, AD7193_CH_AIN2),
1196 	AD7193_CHANNEL(8, 3, AD7193_CH_AIN3),
1197 	AD7193_CHANNEL(9, 4, AD7193_CH_AIN4),
1198 	AD7193_CHANNEL(10, 5, AD7193_CH_AIN5),
1199 	AD7193_CHANNEL(11, 6, AD7193_CH_AIN6),
1200 	AD7193_CHANNEL(12, 7, AD7193_CH_AIN7),
1201 	AD7193_CHANNEL(13, 8, AD7193_CH_AIN8),
1202 	IIO_CHAN_SOFT_TIMESTAMP(14),
1203 };
1204 
ad7194_validate_ain_channel(struct device * dev,u32 ain)1205 static bool ad7194_validate_ain_channel(struct device *dev, u32 ain)
1206 {
1207 	return in_range(ain, AD7194_CH_AIN_START, AD7194_CH_AIN_NR);
1208 }
1209 
ad7194_parse_channels(struct iio_dev * indio_dev)1210 static int ad7194_parse_channels(struct iio_dev *indio_dev)
1211 {
1212 	struct device *dev = indio_dev->dev.parent;
1213 	struct iio_chan_spec *ad7194_channels;
1214 	const struct iio_chan_spec ad7194_chan = AD7193_CHANNEL(0, 0, 0);
1215 	const struct iio_chan_spec ad7194_chan_diff = AD7193_DIFF_CHANNEL(0, 0, 0, 0);
1216 	const struct iio_chan_spec ad7194_chan_temp = AD719x_TEMP_CHANNEL(0, 0);
1217 	const struct iio_chan_spec ad7194_chan_timestamp = IIO_CHAN_SOFT_TIMESTAMP(0);
1218 	unsigned int num_channels, index = 0;
1219 	u32 ain[2];
1220 	int ret;
1221 
1222 	num_channels = device_get_child_node_count(dev);
1223 	if (num_channels > AD7194_CH_MAX_NR)
1224 		return dev_err_probe(dev, -EINVAL, "Too many channels: %u\n",
1225 				     num_channels);
1226 
1227 	num_channels += AD7194_CH_BASE_NR;
1228 
1229 	ad7194_channels = devm_kcalloc(dev, num_channels,
1230 				       sizeof(*ad7194_channels), GFP_KERNEL);
1231 	if (!ad7194_channels)
1232 		return -ENOMEM;
1233 
1234 	indio_dev->channels = ad7194_channels;
1235 	indio_dev->num_channels = num_channels;
1236 
1237 	device_for_each_child_node_scoped(dev, child) {
1238 		ret = fwnode_property_read_u32_array(child, "diff-channels",
1239 						     ain, ARRAY_SIZE(ain));
1240 		if (ret == 0) {
1241 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1242 				return dev_err_probe(dev, -EINVAL,
1243 						     "Invalid AIN channel: %u\n",
1244 						     ain[0]);
1245 
1246 			if (!ad7194_validate_ain_channel(dev, ain[1]))
1247 				return dev_err_probe(dev, -EINVAL,
1248 						     "Invalid AIN channel: %u\n",
1249 						     ain[1]);
1250 
1251 			*ad7194_channels = ad7194_chan_diff;
1252 			ad7194_channels->scan_index = index++;
1253 			ad7194_channels->channel = ain[0];
1254 			ad7194_channels->channel2 = ain[1];
1255 			ad7194_channels->address = AD7194_DIFF_CH(ain[0], ain[1]);
1256 		} else {
1257 			ret = fwnode_property_read_u32(child, "single-channel",
1258 						       &ain[0]);
1259 			if (ret)
1260 				return dev_err_probe(dev, ret,
1261 						     "Missing channel property\n");
1262 
1263 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1264 				return dev_err_probe(dev, -EINVAL,
1265 						     "Invalid AIN channel: %u\n",
1266 						     ain[0]);
1267 
1268 			*ad7194_channels = ad7194_chan;
1269 			ad7194_channels->scan_index = index++;
1270 			ad7194_channels->channel = ain[0];
1271 			ad7194_channels->address = AD7194_CH(ain[0]);
1272 		}
1273 		ad7194_channels++;
1274 	}
1275 
1276 	*ad7194_channels = ad7194_chan_temp;
1277 	ad7194_channels->scan_index = index++;
1278 	ad7194_channels->address = AD7194_CH_TEMP;
1279 	ad7194_channels++;
1280 
1281 	*ad7194_channels = ad7194_chan_timestamp;
1282 	ad7194_channels->scan_index = index;
1283 
1284 	return 0;
1285 }
1286 
1287 static const struct ad7192_chip_info ad7192_chip_info_tbl[] = {
1288 	[ID_AD7190] = {
1289 		.chip_id = CHIPID_AD7190,
1290 		.name = "ad7190",
1291 		.channels = ad7192_channels,
1292 		.num_channels = ARRAY_SIZE(ad7192_channels),
1293 		.sigma_delta_info = &ad7192_sigma_delta_info,
1294 		.info = &ad7192_info,
1295 	},
1296 	[ID_AD7192] = {
1297 		.chip_id = CHIPID_AD7192,
1298 		.name = "ad7192",
1299 		.channels = ad7192_channels,
1300 		.num_channels = ARRAY_SIZE(ad7192_channels),
1301 		.sigma_delta_info = &ad7192_sigma_delta_info,
1302 		.info = &ad7192_info,
1303 	},
1304 	[ID_AD7193] = {
1305 		.chip_id = CHIPID_AD7193,
1306 		.name = "ad7193",
1307 		.channels = ad7193_channels,
1308 		.num_channels = ARRAY_SIZE(ad7193_channels),
1309 		.sigma_delta_info = &ad7192_sigma_delta_info,
1310 		.info = &ad7192_info,
1311 	},
1312 	[ID_AD7194] = {
1313 		.chip_id = CHIPID_AD7194,
1314 		.name = "ad7194",
1315 		.info = &ad7194_info,
1316 		.sigma_delta_info = &ad7194_sigma_delta_info,
1317 		.parse_channels = ad7194_parse_channels,
1318 	},
1319 	[ID_AD7195] = {
1320 		.chip_id = CHIPID_AD7195,
1321 		.name = "ad7195",
1322 		.channels = ad7192_channels,
1323 		.num_channels = ARRAY_SIZE(ad7192_channels),
1324 		.sigma_delta_info = &ad7192_sigma_delta_info,
1325 		.info = &ad7195_info,
1326 	},
1327 };
1328 
ad7192_probe(struct spi_device * spi)1329 static int ad7192_probe(struct spi_device *spi)
1330 {
1331 	struct device *dev = &spi->dev;
1332 	struct ad7192_state *st;
1333 	struct iio_dev *indio_dev;
1334 	int ret, avdd_mv;
1335 
1336 	if (!spi->irq)
1337 		return dev_err_probe(dev, -ENODEV, "Failed to get IRQ\n");
1338 
1339 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1340 	if (!indio_dev)
1341 		return -ENOMEM;
1342 
1343 	st = iio_priv(indio_dev);
1344 
1345 	mutex_init(&st->lock);
1346 
1347 	/*
1348 	 * Regulator aincom is optional to maintain compatibility with older DT.
1349 	 * Newer firmware should provide a zero volt fixed supply if wired to
1350 	 * ground.
1351 	 */
1352 	ret = devm_regulator_get_enable_read_voltage(dev, "aincom");
1353 	if (ret < 0 && ret != -ENODEV)
1354 		return dev_err_probe(dev, ret, "Failed to get AINCOM voltage\n");
1355 
1356 	st->aincom_mv = ret == -ENODEV ? 0 : ret / MILLI;
1357 
1358 	/* AVDD can optionally be used as reference voltage */
1359 	ret = devm_regulator_get_enable_read_voltage(dev, "avdd");
1360 	if (ret == -ENODEV || ret == -EINVAL) {
1361 		int ret2;
1362 
1363 		/*
1364 		 * We get -EINVAL if avdd is a supply with unknown voltage. We
1365 		 * still need to enable it since it is also a power supply.
1366 		 */
1367 		ret2 = devm_regulator_get_enable(dev, "avdd");
1368 		if (ret2)
1369 			return dev_err_probe(dev, ret2,
1370 					     "Failed to enable AVDD supply\n");
1371 	} else if (ret < 0) {
1372 		return dev_err_probe(dev, ret, "Failed to get AVDD voltage\n");
1373 	}
1374 
1375 	avdd_mv = ret == -ENODEV || ret == -EINVAL ? 0 : ret / MILLI;
1376 
1377 	ret = devm_regulator_get_enable(dev, "dvdd");
1378 	if (ret)
1379 		return dev_err_probe(dev, ret, "Failed to enable specified DVdd supply\n");
1380 
1381 	/*
1382 	 * This is either REFIN1 or REFIN2 depending on adi,refin2-pins-enable.
1383 	 * If this supply is not present, fall back to AVDD as reference.
1384 	 */
1385 	ret = devm_regulator_get_enable_read_voltage(dev, "vref");
1386 	if (ret == -ENODEV) {
1387 		if (avdd_mv == 0)
1388 			return dev_err_probe(dev, -ENODEV,
1389 					     "No reference voltage available\n");
1390 	} else if (ret < 0) {
1391 		return ret;
1392 	}
1393 
1394 	st->int_vref_mv = ret == -ENODEV ? avdd_mv : ret / MILLI;
1395 
1396 	st->chip_info = spi_get_device_match_data(spi);
1397 	indio_dev->name = st->chip_info->name;
1398 	indio_dev->modes = INDIO_DIRECT_MODE;
1399 	indio_dev->info = st->chip_info->info;
1400 	if (st->chip_info->parse_channels) {
1401 		ret = st->chip_info->parse_channels(indio_dev);
1402 		if (ret)
1403 			return ret;
1404 	} else {
1405 		indio_dev->channels = st->chip_info->channels;
1406 		indio_dev->num_channels = st->chip_info->num_channels;
1407 	}
1408 
1409 	ret = ad_sd_init(&st->sd, indio_dev, spi, st->chip_info->sigma_delta_info);
1410 	if (ret)
1411 		return ret;
1412 
1413 	ret = devm_ad_sd_setup_buffer_and_trigger(dev, indio_dev);
1414 	if (ret)
1415 		return ret;
1416 
1417 	ret = ad7192_clock_setup(st);
1418 	if (ret)
1419 		return ret;
1420 
1421 	ret = ad7192_setup(indio_dev, dev);
1422 	if (ret)
1423 		return ret;
1424 
1425 	return devm_iio_device_register(dev, indio_dev);
1426 }
1427 
1428 static const struct of_device_id ad7192_of_match[] = {
1429 	{ .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] },
1430 	{ .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] },
1431 	{ .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] },
1432 	{ .compatible = "adi,ad7194", .data = &ad7192_chip_info_tbl[ID_AD7194] },
1433 	{ .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] },
1434 	{ }
1435 };
1436 MODULE_DEVICE_TABLE(of, ad7192_of_match);
1437 
1438 static const struct spi_device_id ad7192_ids[] = {
1439 	{ "ad7190", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7190] },
1440 	{ "ad7192", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7192] },
1441 	{ "ad7193", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7193] },
1442 	{ "ad7194", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7194] },
1443 	{ "ad7195", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7195] },
1444 	{ }
1445 };
1446 MODULE_DEVICE_TABLE(spi, ad7192_ids);
1447 
1448 static struct spi_driver ad7192_driver = {
1449 	.driver = {
1450 		.name	= "ad7192",
1451 		.of_match_table = ad7192_of_match,
1452 	},
1453 	.probe		= ad7192_probe,
1454 	.id_table	= ad7192_ids,
1455 };
1456 module_spi_driver(ad7192_driver);
1457 
1458 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1459 MODULE_DESCRIPTION("Analog Devices AD7192 and similar ADC");
1460 MODULE_LICENSE("GPL v2");
1461 MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA);
1462