xref: /linux/drivers/iio/adc/ad7192.c (revision 2cc699b3c2fe5ea84081059c88c46373cbebe630)
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 	.num_resetclks = 40,
365 };
366 
367 static const struct ad_sigma_delta_info ad7194_sigma_delta_info = {
368 	.set_channel = ad7192_set_channel,
369 	.append_status = ad7192_append_status,
370 	.disable_all = ad7192_disable_all,
371 	.set_mode = ad7192_set_mode,
372 	.has_registers = true,
373 	.addr_shift = 3,
374 	.read_mask = BIT(6),
375 	.status_ch_mask = GENMASK(3, 0),
376 	.irq_flags = IRQF_TRIGGER_FALLING,
377 	.num_resetclks = 40,
378 };
379 
380 static const struct ad_sd_calib_data ad7192_calib_arr[8] = {
381 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
382 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
383 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
384 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
385 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
386 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
387 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
388 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
389 };
390 
ad7192_calibrate_all(struct ad7192_state * st)391 static int ad7192_calibrate_all(struct ad7192_state *st)
392 {
393 	return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr,
394 				   ARRAY_SIZE(ad7192_calib_arr));
395 }
396 
ad7192_valid_external_frequency(u32 freq)397 static inline bool ad7192_valid_external_frequency(u32 freq)
398 {
399 	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
400 		freq <= AD7192_EXT_FREQ_MHZ_MAX);
401 }
402 
403 /*
404  * Position 0 of ad7192_clock_names, xtal, corresponds to clock source
405  * configuration AD7192_CLK_EXT_MCLK1_2 and position 1, mclk, corresponds to
406  * AD7192_CLK_EXT_MCLK2
407  */
408 static const char *const ad7192_clock_names[] = {
409 	"xtal",
410 	"mclk"
411 };
412 
clk_hw_to_ad7192(struct clk_hw * hw)413 static struct ad7192_state *clk_hw_to_ad7192(struct clk_hw *hw)
414 {
415 	return container_of(hw, struct ad7192_state, int_clk_hw);
416 }
417 
ad7192_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)418 static unsigned long ad7192_clk_recalc_rate(struct clk_hw *hw,
419 					    unsigned long parent_rate)
420 {
421 	return AD7192_INT_FREQ_MHZ;
422 }
423 
ad7192_clk_output_is_enabled(struct clk_hw * hw)424 static int ad7192_clk_output_is_enabled(struct clk_hw *hw)
425 {
426 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
427 
428 	return st->clock_sel == AD7192_CLK_INT_CO;
429 }
430 
ad7192_clk_prepare(struct clk_hw * hw)431 static int ad7192_clk_prepare(struct clk_hw *hw)
432 {
433 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
434 	int ret;
435 
436 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
437 	st->mode |= AD7192_CLK_INT_CO;
438 
439 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
440 	if (ret)
441 		return ret;
442 
443 	st->clock_sel = AD7192_CLK_INT_CO;
444 
445 	return 0;
446 }
447 
ad7192_clk_unprepare(struct clk_hw * hw)448 static void ad7192_clk_unprepare(struct clk_hw *hw)
449 {
450 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
451 	int ret;
452 
453 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
454 	st->mode |= AD7192_CLK_INT;
455 
456 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
457 	if (ret)
458 		return;
459 
460 	st->clock_sel = AD7192_CLK_INT;
461 }
462 
463 static const struct clk_ops ad7192_int_clk_ops = {
464 	.recalc_rate = ad7192_clk_recalc_rate,
465 	.is_enabled = ad7192_clk_output_is_enabled,
466 	.prepare = ad7192_clk_prepare,
467 	.unprepare = ad7192_clk_unprepare,
468 };
469 
ad7192_register_clk_provider(struct ad7192_state * st)470 static int ad7192_register_clk_provider(struct ad7192_state *st)
471 {
472 	struct device *dev = &st->sd.spi->dev;
473 	struct clk_init_data init = {};
474 	int ret;
475 
476 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
477 		return 0;
478 
479 	if (!device_property_present(dev, "#clock-cells"))
480 		return 0;
481 
482 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk",
483 				   fwnode_get_name(dev_fwnode(dev)));
484 	if (!init.name)
485 		return -ENOMEM;
486 
487 	init.ops = &ad7192_int_clk_ops;
488 
489 	st->int_clk_hw.init = &init;
490 	ret = devm_clk_hw_register(dev, &st->int_clk_hw);
491 	if (ret)
492 		return ret;
493 
494 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
495 					   &st->int_clk_hw);
496 }
497 
ad7192_clock_setup(struct ad7192_state * st)498 static int ad7192_clock_setup(struct ad7192_state *st)
499 {
500 	struct device *dev = &st->sd.spi->dev;
501 	int ret;
502 
503 	/*
504 	 * The following two if branches are kept for backward compatibility but
505 	 * the use of the two devicetree properties is highly discouraged. Clock
506 	 * configuration should be done according to the bindings.
507 	 */
508 
509 	if (device_property_read_bool(dev, "adi,int-clock-output-enable")) {
510 		st->clock_sel = AD7192_CLK_INT_CO;
511 		st->fclk = AD7192_INT_FREQ_MHZ;
512 		dev_warn(dev, "Property adi,int-clock-output-enable is deprecated! Check bindings!\n");
513 		return 0;
514 	}
515 
516 	if (device_property_read_bool(dev, "adi,clock-xtal")) {
517 		st->clock_sel = AD7192_CLK_EXT_MCLK1_2;
518 		st->mclk = devm_clk_get_enabled(dev, "mclk");
519 		if (IS_ERR(st->mclk))
520 			return dev_err_probe(dev, PTR_ERR(st->mclk),
521 					     "Failed to get mclk\n");
522 
523 		st->fclk = clk_get_rate(st->mclk);
524 		if (!ad7192_valid_external_frequency(st->fclk))
525 			return dev_err_probe(dev, -EINVAL,
526 					     "External clock frequency out of bounds\n");
527 
528 		dev_warn(dev, "Property adi,clock-xtal is deprecated! Check bindings!\n");
529 		return 0;
530 	}
531 
532 	ret = device_property_match_property_string(dev, "clock-names",
533 						    ad7192_clock_names,
534 						    ARRAY_SIZE(ad7192_clock_names));
535 	if (ret < 0) {
536 		st->clock_sel = AD7192_CLK_INT;
537 		st->fclk = AD7192_INT_FREQ_MHZ;
538 
539 		ret = ad7192_register_clk_provider(st);
540 		if (ret)
541 			return dev_err_probe(dev, ret,
542 					     "Failed to register clock provider\n");
543 		return 0;
544 	}
545 
546 	st->clock_sel = AD7192_CLK_EXT_MCLK1_2 + ret;
547 
548 	st->mclk = devm_clk_get_enabled(dev, ad7192_clock_names[ret]);
549 	if (IS_ERR(st->mclk))
550 		return dev_err_probe(dev, PTR_ERR(st->mclk),
551 				     "Failed to get clock source\n");
552 
553 	st->fclk = clk_get_rate(st->mclk);
554 	if (!ad7192_valid_external_frequency(st->fclk))
555 		return dev_err_probe(dev, -EINVAL,
556 				     "External clock frequency out of bounds\n");
557 
558 	return 0;
559 }
560 
ad7192_setup(struct iio_dev * indio_dev,struct device * dev)561 static int ad7192_setup(struct iio_dev *indio_dev, struct device *dev)
562 {
563 	struct ad7192_state *st = iio_priv(indio_dev);
564 	bool rej60_en, refin2_en;
565 	bool buf_en, bipolar, burnout_curr_en;
566 	unsigned long long scale_uv;
567 	int i, ret, id;
568 
569 	/* reset the serial interface */
570 	ret = ad_sd_reset(&st->sd);
571 	if (ret < 0)
572 		return ret;
573 	usleep_range(500, 1000); /* Wait for at least 500us */
574 
575 	/* write/read test for device presence */
576 	ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id);
577 	if (ret)
578 		return ret;
579 
580 	id = FIELD_GET(AD7192_ID_MASK, id);
581 
582 	if (id != st->chip_info->chip_id)
583 		dev_warn(dev, "device ID query failed (0x%X != 0x%X)\n",
584 			 id, st->chip_info->chip_id);
585 
586 	st->mode = FIELD_PREP(AD7192_MODE_SEL_MASK, AD7192_MODE_IDLE) |
587 		FIELD_PREP(AD7192_MODE_CLKSRC_MASK, st->clock_sel) |
588 		FIELD_PREP(AD7192_MODE_RATE_MASK, 480);
589 
590 	st->conf = FIELD_PREP(AD7192_CONF_GAIN_MASK, 0);
591 
592 	rej60_en = device_property_read_bool(dev, "adi,rejection-60-Hz-enable");
593 	if (rej60_en)
594 		st->mode |= AD7192_MODE_REJ60;
595 
596 	refin2_en = device_property_read_bool(dev, "adi,refin2-pins-enable");
597 	if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195)
598 		st->conf |= AD7192_CONF_REFSEL;
599 
600 	st->conf &= ~AD7192_CONF_CHOP;
601 
602 	buf_en = device_property_read_bool(dev, "adi,buffer-enable");
603 	if (buf_en)
604 		st->conf |= AD7192_CONF_BUF;
605 
606 	bipolar = device_property_read_bool(dev, "bipolar");
607 	if (!bipolar)
608 		st->conf |= AD7192_CONF_UNIPOLAR;
609 
610 	burnout_curr_en = device_property_read_bool(dev,
611 						    "adi,burnout-currents-enable");
612 	if (burnout_curr_en && buf_en) {
613 		st->conf |= AD7192_CONF_BURN;
614 	} else if (burnout_curr_en) {
615 		dev_warn(dev,
616 			 "Can't enable burnout currents: see CHOP or buffer\n");
617 	}
618 
619 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
620 	if (ret)
621 		return ret;
622 
623 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
624 	if (ret)
625 		return ret;
626 
627 	ret = ad7192_calibrate_all(st);
628 	if (ret)
629 		return ret;
630 
631 	/* Populate available ADC input ranges */
632 	for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
633 		scale_uv = ((u64)st->int_vref_mv * 100000000)
634 			>> (indio_dev->channels[0].scan_type.realbits -
635 			!FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf));
636 		scale_uv >>= i;
637 
638 		st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
639 		st->scale_avail[i][0] = scale_uv;
640 	}
641 
642 	st->oversampling_ratio_avail[0] = 1;
643 	st->oversampling_ratio_avail[1] = 2;
644 	st->oversampling_ratio_avail[2] = 8;
645 	st->oversampling_ratio_avail[3] = 16;
646 
647 	st->filter_freq_avail[0][0] = 600;
648 	st->filter_freq_avail[1][0] = 800;
649 	st->filter_freq_avail[2][0] = 2300;
650 	st->filter_freq_avail[3][0] = 2720;
651 
652 	st->filter_freq_avail[0][1] = 1000;
653 	st->filter_freq_avail[1][1] = 1000;
654 	st->filter_freq_avail[2][1] = 1000;
655 	st->filter_freq_avail[3][1] = 1000;
656 
657 	return 0;
658 }
659 
ad7192_show_ac_excitation(struct device * dev,struct device_attribute * attr,char * buf)660 static ssize_t ad7192_show_ac_excitation(struct device *dev,
661 					 struct device_attribute *attr,
662 					 char *buf)
663 {
664 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
665 	struct ad7192_state *st = iio_priv(indio_dev);
666 
667 	return sysfs_emit(buf, "%ld\n", FIELD_GET(AD7192_CONF_ACX, st->conf));
668 }
669 
ad7192_show_bridge_switch(struct device * dev,struct device_attribute * attr,char * buf)670 static ssize_t ad7192_show_bridge_switch(struct device *dev,
671 					 struct device_attribute *attr,
672 					 char *buf)
673 {
674 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
675 	struct ad7192_state *st = iio_priv(indio_dev);
676 
677 	return sysfs_emit(buf, "%ld\n",
678 			  FIELD_GET(AD7192_GPOCON_BPDSW, st->gpocon));
679 }
680 
ad7192_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)681 static ssize_t ad7192_set(struct device *dev,
682 			  struct device_attribute *attr,
683 			  const char *buf,
684 			  size_t len)
685 {
686 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
687 	struct ad7192_state *st = iio_priv(indio_dev);
688 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
689 	int ret;
690 	bool val;
691 
692 	ret = kstrtobool(buf, &val);
693 	if (ret < 0)
694 		return ret;
695 
696 	ret = iio_device_claim_direct_mode(indio_dev);
697 	if (ret)
698 		return ret;
699 
700 	switch ((u32)this_attr->address) {
701 	case AD7192_REG_GPOCON:
702 		if (val)
703 			st->gpocon |= AD7192_GPOCON_BPDSW;
704 		else
705 			st->gpocon &= ~AD7192_GPOCON_BPDSW;
706 
707 		ad_sd_write_reg(&st->sd, AD7192_REG_GPOCON, 1, st->gpocon);
708 		break;
709 	case AD7192_REG_CONF:
710 		if (val)
711 			st->conf |= AD7192_CONF_ACX;
712 		else
713 			st->conf &= ~AD7192_CONF_ACX;
714 
715 		ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
716 		break;
717 	default:
718 		ret = -EINVAL;
719 	}
720 
721 	iio_device_release_direct_mode(indio_dev);
722 
723 	return ret ? ret : len;
724 }
725 
ad7192_compute_f_order(struct ad7192_state * st,bool sinc3_en,bool chop_en)726 static int ad7192_compute_f_order(struct ad7192_state *st, bool sinc3_en, bool chop_en)
727 {
728 	u8 avg_factor_selected, oversampling_ratio;
729 
730 	avg_factor_selected = FIELD_GET(AD7192_MODE_AVG_MASK, st->mode);
731 
732 	if (!avg_factor_selected && !chop_en)
733 		return 1;
734 
735 	oversampling_ratio = st->oversampling_ratio_avail[avg_factor_selected];
736 
737 	if (sinc3_en)
738 		return AD7192_SYNC3_FILTER + oversampling_ratio - 1;
739 
740 	return AD7192_SYNC4_FILTER + oversampling_ratio - 1;
741 }
742 
ad7192_get_f_order(struct ad7192_state * st)743 static int ad7192_get_f_order(struct ad7192_state *st)
744 {
745 	bool sinc3_en, chop_en;
746 
747 	sinc3_en = FIELD_GET(AD7192_MODE_SINC3, st->mode);
748 	chop_en = FIELD_GET(AD7192_CONF_CHOP, st->conf);
749 
750 	return ad7192_compute_f_order(st, sinc3_en, chop_en);
751 }
752 
ad7192_compute_f_adc(struct ad7192_state * st,bool sinc3_en,bool chop_en)753 static int ad7192_compute_f_adc(struct ad7192_state *st, bool sinc3_en,
754 				bool chop_en)
755 {
756 	unsigned int f_order = ad7192_compute_f_order(st, sinc3_en, chop_en);
757 
758 	return DIV_ROUND_CLOSEST(st->fclk,
759 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
760 }
761 
ad7192_get_f_adc(struct ad7192_state * st)762 static int ad7192_get_f_adc(struct ad7192_state *st)
763 {
764 	unsigned int f_order = ad7192_get_f_order(st);
765 
766 	return DIV_ROUND_CLOSEST(st->fclk,
767 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
768 }
769 
ad7192_update_filter_freq_avail(struct ad7192_state * st)770 static void ad7192_update_filter_freq_avail(struct ad7192_state *st)
771 {
772 	unsigned int fadc;
773 
774 	/* Formulas for filter at page 25 of the datasheet */
775 	fadc = ad7192_compute_f_adc(st, false, true);
776 	st->filter_freq_avail[0][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
777 
778 	fadc = ad7192_compute_f_adc(st, true, true);
779 	st->filter_freq_avail[1][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
780 
781 	fadc = ad7192_compute_f_adc(st, false, false);
782 	st->filter_freq_avail[2][0] = DIV_ROUND_CLOSEST(fadc * 230, 1024);
783 
784 	fadc = ad7192_compute_f_adc(st, true, false);
785 	st->filter_freq_avail[3][0] = DIV_ROUND_CLOSEST(fadc * 272, 1024);
786 }
787 
788 static IIO_DEVICE_ATTR(bridge_switch_en, 0644,
789 		       ad7192_show_bridge_switch, ad7192_set,
790 		       AD7192_REG_GPOCON);
791 
792 static IIO_DEVICE_ATTR(ac_excitation_en, 0644,
793 		       ad7192_show_ac_excitation, ad7192_set,
794 		       AD7192_REG_CONF);
795 
796 static struct attribute *ad7192_attributes[] = {
797 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
798 	NULL
799 };
800 
801 static const struct attribute_group ad7192_attribute_group = {
802 	.attrs = ad7192_attributes,
803 };
804 
805 static struct attribute *ad7195_attributes[] = {
806 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
807 	&iio_dev_attr_ac_excitation_en.dev_attr.attr,
808 	NULL
809 };
810 
811 static const struct attribute_group ad7195_attribute_group = {
812 	.attrs = ad7195_attributes,
813 };
814 
ad7192_get_temp_scale(bool unipolar)815 static unsigned int ad7192_get_temp_scale(bool unipolar)
816 {
817 	return unipolar ? 2815 * 2 : 2815;
818 }
819 
ad7192_set_3db_filter_freq(struct ad7192_state * st,int val,int val2)820 static int ad7192_set_3db_filter_freq(struct ad7192_state *st,
821 				      int val, int val2)
822 {
823 	int i, ret, freq;
824 	unsigned int diff_new, diff_old;
825 	int idx = 0;
826 
827 	diff_old = U32_MAX;
828 	freq = val * 1000 + val2;
829 
830 	for (i = 0; i < ARRAY_SIZE(st->filter_freq_avail); i++) {
831 		diff_new = abs(freq - st->filter_freq_avail[i][0]);
832 		if (diff_new < diff_old) {
833 			diff_old = diff_new;
834 			idx = i;
835 		}
836 	}
837 
838 	switch (idx) {
839 	case 0:
840 		st->mode &= ~AD7192_MODE_SINC3;
841 
842 		st->conf |= AD7192_CONF_CHOP;
843 		break;
844 	case 1:
845 		st->mode |= AD7192_MODE_SINC3;
846 
847 		st->conf |= AD7192_CONF_CHOP;
848 		break;
849 	case 2:
850 		st->mode &= ~AD7192_MODE_SINC3;
851 
852 		st->conf &= ~AD7192_CONF_CHOP;
853 		break;
854 	case 3:
855 		st->mode |= AD7192_MODE_SINC3;
856 
857 		st->conf &= ~AD7192_CONF_CHOP;
858 		break;
859 	}
860 
861 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
862 	if (ret < 0)
863 		return ret;
864 
865 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
866 }
867 
ad7192_get_3db_filter_freq(struct ad7192_state * st)868 static int ad7192_get_3db_filter_freq(struct ad7192_state *st)
869 {
870 	unsigned int fadc;
871 
872 	fadc = ad7192_get_f_adc(st);
873 
874 	if (FIELD_GET(AD7192_CONF_CHOP, st->conf))
875 		return DIV_ROUND_CLOSEST(fadc * 240, 1024);
876 	if (FIELD_GET(AD7192_MODE_SINC3, st->mode))
877 		return DIV_ROUND_CLOSEST(fadc * 272, 1024);
878 	else
879 		return DIV_ROUND_CLOSEST(fadc * 230, 1024);
880 }
881 
ad7192_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)882 static int ad7192_read_raw(struct iio_dev *indio_dev,
883 			   struct iio_chan_spec const *chan,
884 			   int *val,
885 			   int *val2,
886 			   long m)
887 {
888 	struct ad7192_state *st = iio_priv(indio_dev);
889 	bool unipolar = FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf);
890 	u8 gain = FIELD_GET(AD7192_CONF_GAIN_MASK, st->conf);
891 
892 	switch (m) {
893 	case IIO_CHAN_INFO_RAW:
894 		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
895 	case IIO_CHAN_INFO_SCALE:
896 		switch (chan->type) {
897 		case IIO_VOLTAGE:
898 			mutex_lock(&st->lock);
899 			*val = st->scale_avail[gain][0];
900 			*val2 = st->scale_avail[gain][1];
901 			mutex_unlock(&st->lock);
902 			return IIO_VAL_INT_PLUS_NANO;
903 		case IIO_TEMP:
904 			*val = 0;
905 			*val2 = 1000000000 / ad7192_get_temp_scale(unipolar);
906 			return IIO_VAL_INT_PLUS_NANO;
907 		default:
908 			return -EINVAL;
909 		}
910 	case IIO_CHAN_INFO_OFFSET:
911 		if (!unipolar)
912 			*val = -(1 << (chan->scan_type.realbits - 1));
913 		else
914 			*val = 0;
915 
916 		switch (chan->type) {
917 		case IIO_VOLTAGE:
918 			/*
919 			 * Only applies to pseudo-differential inputs.
920 			 * AINCOM voltage has to be converted to "raw" units.
921 			 */
922 			if (st->aincom_mv && !chan->differential)
923 				*val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * NANO,
924 							      st->scale_avail[gain][1]);
925 			return IIO_VAL_INT;
926 		/* Kelvin to Celsius */
927 		case IIO_TEMP:
928 			*val -= 273 * ad7192_get_temp_scale(unipolar);
929 			return IIO_VAL_INT;
930 		default:
931 			return -EINVAL;
932 		}
933 	case IIO_CHAN_INFO_SAMP_FREQ:
934 		*val = DIV_ROUND_CLOSEST(ad7192_get_f_adc(st), 1024);
935 		return IIO_VAL_INT;
936 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
937 		*val = ad7192_get_3db_filter_freq(st);
938 		*val2 = 1000;
939 		return IIO_VAL_FRACTIONAL;
940 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
941 		*val = st->oversampling_ratio_avail[FIELD_GET(AD7192_MODE_AVG_MASK, st->mode)];
942 		return IIO_VAL_INT;
943 	}
944 
945 	return -EINVAL;
946 }
947 
ad7192_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)948 static int ad7192_write_raw(struct iio_dev *indio_dev,
949 			    struct iio_chan_spec const *chan,
950 			    int val,
951 			    int val2,
952 			    long mask)
953 {
954 	struct ad7192_state *st = iio_priv(indio_dev);
955 	int ret, i, div;
956 	unsigned int tmp;
957 
958 	ret = iio_device_claim_direct_mode(indio_dev);
959 	if (ret)
960 		return ret;
961 
962 	mutex_lock(&st->lock);
963 
964 	switch (mask) {
965 	case IIO_CHAN_INFO_SCALE:
966 		ret = -EINVAL;
967 		for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
968 			if (val2 == st->scale_avail[i][1]) {
969 				ret = 0;
970 				tmp = st->conf;
971 				st->conf &= ~AD7192_CONF_GAIN_MASK;
972 				st->conf |= FIELD_PREP(AD7192_CONF_GAIN_MASK, i);
973 				if (tmp == st->conf)
974 					break;
975 				ad_sd_write_reg(&st->sd, AD7192_REG_CONF,
976 						3, st->conf);
977 				ad7192_calibrate_all(st);
978 				break;
979 			}
980 		break;
981 	case IIO_CHAN_INFO_SAMP_FREQ:
982 		if (!val) {
983 			ret = -EINVAL;
984 			break;
985 		}
986 
987 		div = st->fclk / (val * ad7192_get_f_order(st) * 1024);
988 		if (div < 1 || div > 1023) {
989 			ret = -EINVAL;
990 			break;
991 		}
992 
993 		st->mode &= ~AD7192_MODE_RATE_MASK;
994 		st->mode |= FIELD_PREP(AD7192_MODE_RATE_MASK, div);
995 		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
996 		ad7192_update_filter_freq_avail(st);
997 		break;
998 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
999 		ret = ad7192_set_3db_filter_freq(st, val, val2 / 1000);
1000 		break;
1001 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1002 		ret = -EINVAL;
1003 		for (i = 0; i < ARRAY_SIZE(st->oversampling_ratio_avail); i++)
1004 			if (val == st->oversampling_ratio_avail[i]) {
1005 				ret = 0;
1006 				tmp = st->mode;
1007 				st->mode &= ~AD7192_MODE_AVG_MASK;
1008 				st->mode |= FIELD_PREP(AD7192_MODE_AVG_MASK, i);
1009 				if (tmp == st->mode)
1010 					break;
1011 				ad_sd_write_reg(&st->sd, AD7192_REG_MODE,
1012 						3, st->mode);
1013 				break;
1014 			}
1015 		ad7192_update_filter_freq_avail(st);
1016 		break;
1017 	default:
1018 		ret = -EINVAL;
1019 	}
1020 
1021 	mutex_unlock(&st->lock);
1022 
1023 	iio_device_release_direct_mode(indio_dev);
1024 
1025 	return ret;
1026 }
1027 
ad7192_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)1028 static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
1029 				    struct iio_chan_spec const *chan,
1030 				    long mask)
1031 {
1032 	switch (mask) {
1033 	case IIO_CHAN_INFO_SCALE:
1034 		return IIO_VAL_INT_PLUS_NANO;
1035 	case IIO_CHAN_INFO_SAMP_FREQ:
1036 		return IIO_VAL_INT;
1037 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1038 		return IIO_VAL_INT_PLUS_MICRO;
1039 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1040 		return IIO_VAL_INT;
1041 	default:
1042 		return -EINVAL;
1043 	}
1044 }
1045 
ad7192_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)1046 static int ad7192_read_avail(struct iio_dev *indio_dev,
1047 			     struct iio_chan_spec const *chan,
1048 			     const int **vals, int *type, int *length,
1049 			     long mask)
1050 {
1051 	struct ad7192_state *st = iio_priv(indio_dev);
1052 
1053 	switch (mask) {
1054 	case IIO_CHAN_INFO_SCALE:
1055 		*vals = (int *)st->scale_avail;
1056 		*type = IIO_VAL_INT_PLUS_NANO;
1057 		/* Values are stored in a 2D matrix  */
1058 		*length = ARRAY_SIZE(st->scale_avail) * 2;
1059 
1060 		return IIO_AVAIL_LIST;
1061 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1062 		*vals = (int *)st->filter_freq_avail;
1063 		*type = IIO_VAL_FRACTIONAL;
1064 		*length = ARRAY_SIZE(st->filter_freq_avail) * 2;
1065 
1066 		return IIO_AVAIL_LIST;
1067 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1068 		*vals = (int *)st->oversampling_ratio_avail;
1069 		*type = IIO_VAL_INT;
1070 		*length = ARRAY_SIZE(st->oversampling_ratio_avail);
1071 
1072 		return IIO_AVAIL_LIST;
1073 	}
1074 
1075 	return -EINVAL;
1076 }
1077 
ad7192_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)1078 static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask)
1079 {
1080 	struct ad7192_state *st = iio_priv(indio_dev);
1081 	u32 conf = st->conf;
1082 	int ret;
1083 	int i;
1084 
1085 	conf &= ~AD7192_CONF_CHAN_MASK;
1086 	for_each_set_bit(i, scan_mask, 8)
1087 		conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, BIT(i));
1088 
1089 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
1090 	if (ret < 0)
1091 		return ret;
1092 
1093 	st->conf = conf;
1094 
1095 	return 0;
1096 }
1097 
1098 static const struct iio_info ad7192_info = {
1099 	.read_raw = ad7192_read_raw,
1100 	.write_raw = ad7192_write_raw,
1101 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1102 	.read_avail = ad7192_read_avail,
1103 	.attrs = &ad7192_attribute_group,
1104 	.validate_trigger = ad_sd_validate_trigger,
1105 	.update_scan_mode = ad7192_update_scan_mode,
1106 };
1107 
1108 static const struct iio_info ad7194_info = {
1109 	.read_raw = ad7192_read_raw,
1110 	.write_raw = ad7192_write_raw,
1111 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1112 	.read_avail = ad7192_read_avail,
1113 	.validate_trigger = ad_sd_validate_trigger,
1114 };
1115 
1116 static const struct iio_info ad7195_info = {
1117 	.read_raw = ad7192_read_raw,
1118 	.write_raw = ad7192_write_raw,
1119 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1120 	.read_avail = ad7192_read_avail,
1121 	.attrs = &ad7195_attribute_group,
1122 	.validate_trigger = ad_sd_validate_trigger,
1123 	.update_scan_mode = ad7192_update_scan_mode,
1124 };
1125 
1126 #define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _type, \
1127 	_mask_all, _mask_type_av, _mask_all_av, _ext_info) \
1128 	{ \
1129 		.type = (_type), \
1130 		.differential = ((_channel2) == -1 ? 0 : 1), \
1131 		.indexed = 1, \
1132 		.channel = (_channel1), \
1133 		.channel2 = (_channel2), \
1134 		.address = (_address), \
1135 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1136 			BIT(IIO_CHAN_INFO_OFFSET), \
1137 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
1138 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
1139 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1140 			(_mask_all), \
1141 		.info_mask_shared_by_type_available = (_mask_type_av), \
1142 		.info_mask_shared_by_all_available = \
1143 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1144 			(_mask_all_av), \
1145 		.ext_info = (_ext_info), \
1146 		.scan_index = (_si), \
1147 		.scan_type = { \
1148 			.sign = 'u', \
1149 			.realbits = 24, \
1150 			.storagebits = 32, \
1151 			.endianness = IIO_BE, \
1152 		}, \
1153 	}
1154 
1155 #define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1156 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, IIO_VOLTAGE, 0, \
1157 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1158 
1159 #define AD719x_CHANNEL(_si, _channel1, _address) \
1160 	__AD719x_CHANNEL(_si, _channel1, -1, _address, IIO_VOLTAGE, 0, \
1161 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1162 
1163 #define AD719x_TEMP_CHANNEL(_si, _address) \
1164 	__AD719x_CHANNEL(_si, 0, -1, _address, IIO_TEMP, 0, 0, 0, NULL)
1165 
1166 #define AD7193_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1167 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, \
1168 		IIO_VOLTAGE, \
1169 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1170 		BIT(IIO_CHAN_INFO_SCALE), \
1171 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1172 		ad7192_calibsys_ext_info)
1173 
1174 #define AD7193_CHANNEL(_si, _channel1, _address) \
1175 	AD7193_DIFF_CHANNEL(_si, _channel1, -1, _address)
1176 
1177 static const struct iio_chan_spec ad7192_channels[] = {
1178 	AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
1179 	AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
1180 	AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
1181 	AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M),
1182 	AD719x_CHANNEL(4, 1, AD7192_CH_AIN1),
1183 	AD719x_CHANNEL(5, 2, AD7192_CH_AIN2),
1184 	AD719x_CHANNEL(6, 3, AD7192_CH_AIN3),
1185 	AD719x_CHANNEL(7, 4, AD7192_CH_AIN4),
1186 	IIO_CHAN_SOFT_TIMESTAMP(8),
1187 };
1188 
1189 static const struct iio_chan_spec ad7193_channels[] = {
1190 	AD7193_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
1191 	AD7193_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
1192 	AD7193_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
1193 	AD7193_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M),
1194 	AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP),
1195 	AD7193_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M),
1196 	AD7193_CHANNEL(6, 1, AD7193_CH_AIN1),
1197 	AD7193_CHANNEL(7, 2, AD7193_CH_AIN2),
1198 	AD7193_CHANNEL(8, 3, AD7193_CH_AIN3),
1199 	AD7193_CHANNEL(9, 4, AD7193_CH_AIN4),
1200 	AD7193_CHANNEL(10, 5, AD7193_CH_AIN5),
1201 	AD7193_CHANNEL(11, 6, AD7193_CH_AIN6),
1202 	AD7193_CHANNEL(12, 7, AD7193_CH_AIN7),
1203 	AD7193_CHANNEL(13, 8, AD7193_CH_AIN8),
1204 	IIO_CHAN_SOFT_TIMESTAMP(14),
1205 };
1206 
ad7194_validate_ain_channel(struct device * dev,u32 ain)1207 static bool ad7194_validate_ain_channel(struct device *dev, u32 ain)
1208 {
1209 	return in_range(ain, AD7194_CH_AIN_START, AD7194_CH_AIN_NR);
1210 }
1211 
ad7194_parse_channels(struct iio_dev * indio_dev)1212 static int ad7194_parse_channels(struct iio_dev *indio_dev)
1213 {
1214 	struct device *dev = indio_dev->dev.parent;
1215 	struct iio_chan_spec *ad7194_channels;
1216 	const struct iio_chan_spec ad7194_chan = AD7193_CHANNEL(0, 0, 0);
1217 	const struct iio_chan_spec ad7194_chan_diff = AD7193_DIFF_CHANNEL(0, 0, 0, 0);
1218 	const struct iio_chan_spec ad7194_chan_temp = AD719x_TEMP_CHANNEL(0, 0);
1219 	const struct iio_chan_spec ad7194_chan_timestamp = IIO_CHAN_SOFT_TIMESTAMP(0);
1220 	unsigned int num_channels, index = 0;
1221 	u32 ain[2];
1222 	int ret;
1223 
1224 	num_channels = device_get_child_node_count(dev);
1225 	if (num_channels > AD7194_CH_MAX_NR)
1226 		return dev_err_probe(dev, -EINVAL, "Too many channels: %u\n",
1227 				     num_channels);
1228 
1229 	num_channels += AD7194_CH_BASE_NR;
1230 
1231 	ad7194_channels = devm_kcalloc(dev, num_channels,
1232 				       sizeof(*ad7194_channels), GFP_KERNEL);
1233 	if (!ad7194_channels)
1234 		return -ENOMEM;
1235 
1236 	indio_dev->channels = ad7194_channels;
1237 	indio_dev->num_channels = num_channels;
1238 
1239 	device_for_each_child_node_scoped(dev, child) {
1240 		ret = fwnode_property_read_u32_array(child, "diff-channels",
1241 						     ain, ARRAY_SIZE(ain));
1242 		if (ret == 0) {
1243 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1244 				return dev_err_probe(dev, -EINVAL,
1245 						     "Invalid AIN channel: %u\n",
1246 						     ain[0]);
1247 
1248 			if (!ad7194_validate_ain_channel(dev, ain[1]))
1249 				return dev_err_probe(dev, -EINVAL,
1250 						     "Invalid AIN channel: %u\n",
1251 						     ain[1]);
1252 
1253 			*ad7194_channels = ad7194_chan_diff;
1254 			ad7194_channels->scan_index = index++;
1255 			ad7194_channels->channel = ain[0];
1256 			ad7194_channels->channel2 = ain[1];
1257 			ad7194_channels->address = AD7194_DIFF_CH(ain[0], ain[1]);
1258 		} else {
1259 			ret = fwnode_property_read_u32(child, "single-channel",
1260 						       &ain[0]);
1261 			if (ret)
1262 				return dev_err_probe(dev, ret,
1263 						     "Missing channel property\n");
1264 
1265 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1266 				return dev_err_probe(dev, -EINVAL,
1267 						     "Invalid AIN channel: %u\n",
1268 						     ain[0]);
1269 
1270 			*ad7194_channels = ad7194_chan;
1271 			ad7194_channels->scan_index = index++;
1272 			ad7194_channels->channel = ain[0];
1273 			ad7194_channels->address = AD7194_CH(ain[0]);
1274 		}
1275 		ad7194_channels++;
1276 	}
1277 
1278 	*ad7194_channels = ad7194_chan_temp;
1279 	ad7194_channels->scan_index = index++;
1280 	ad7194_channels->address = AD7194_CH_TEMP;
1281 	ad7194_channels++;
1282 
1283 	*ad7194_channels = ad7194_chan_timestamp;
1284 	ad7194_channels->scan_index = index;
1285 
1286 	return 0;
1287 }
1288 
1289 static const struct ad7192_chip_info ad7192_chip_info_tbl[] = {
1290 	[ID_AD7190] = {
1291 		.chip_id = CHIPID_AD7190,
1292 		.name = "ad7190",
1293 		.channels = ad7192_channels,
1294 		.num_channels = ARRAY_SIZE(ad7192_channels),
1295 		.sigma_delta_info = &ad7192_sigma_delta_info,
1296 		.info = &ad7192_info,
1297 	},
1298 	[ID_AD7192] = {
1299 		.chip_id = CHIPID_AD7192,
1300 		.name = "ad7192",
1301 		.channels = ad7192_channels,
1302 		.num_channels = ARRAY_SIZE(ad7192_channels),
1303 		.sigma_delta_info = &ad7192_sigma_delta_info,
1304 		.info = &ad7192_info,
1305 	},
1306 	[ID_AD7193] = {
1307 		.chip_id = CHIPID_AD7193,
1308 		.name = "ad7193",
1309 		.channels = ad7193_channels,
1310 		.num_channels = ARRAY_SIZE(ad7193_channels),
1311 		.sigma_delta_info = &ad7192_sigma_delta_info,
1312 		.info = &ad7192_info,
1313 	},
1314 	[ID_AD7194] = {
1315 		.chip_id = CHIPID_AD7194,
1316 		.name = "ad7194",
1317 		.info = &ad7194_info,
1318 		.sigma_delta_info = &ad7194_sigma_delta_info,
1319 		.parse_channels = ad7194_parse_channels,
1320 	},
1321 	[ID_AD7195] = {
1322 		.chip_id = CHIPID_AD7195,
1323 		.name = "ad7195",
1324 		.channels = ad7192_channels,
1325 		.num_channels = ARRAY_SIZE(ad7192_channels),
1326 		.sigma_delta_info = &ad7192_sigma_delta_info,
1327 		.info = &ad7195_info,
1328 	},
1329 };
1330 
ad7192_probe(struct spi_device * spi)1331 static int ad7192_probe(struct spi_device *spi)
1332 {
1333 	struct device *dev = &spi->dev;
1334 	struct ad7192_state *st;
1335 	struct iio_dev *indio_dev;
1336 	int ret, avdd_mv;
1337 
1338 	if (!spi->irq)
1339 		return dev_err_probe(dev, -ENODEV, "Failed to get IRQ\n");
1340 
1341 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1342 	if (!indio_dev)
1343 		return -ENOMEM;
1344 
1345 	st = iio_priv(indio_dev);
1346 
1347 	mutex_init(&st->lock);
1348 
1349 	/*
1350 	 * Regulator aincom is optional to maintain compatibility with older DT.
1351 	 * Newer firmware should provide a zero volt fixed supply if wired to
1352 	 * ground.
1353 	 */
1354 	ret = devm_regulator_get_enable_read_voltage(dev, "aincom");
1355 	if (ret < 0 && ret != -ENODEV)
1356 		return dev_err_probe(dev, ret, "Failed to get AINCOM voltage\n");
1357 
1358 	st->aincom_mv = ret == -ENODEV ? 0 : ret / MILLI;
1359 
1360 	/* AVDD can optionally be used as reference voltage */
1361 	ret = devm_regulator_get_enable_read_voltage(dev, "avdd");
1362 	if (ret == -ENODEV || ret == -EINVAL) {
1363 		int ret2;
1364 
1365 		/*
1366 		 * We get -EINVAL if avdd is a supply with unknown voltage. We
1367 		 * still need to enable it since it is also a power supply.
1368 		 */
1369 		ret2 = devm_regulator_get_enable(dev, "avdd");
1370 		if (ret2)
1371 			return dev_err_probe(dev, ret2,
1372 					     "Failed to enable AVDD supply\n");
1373 	} else if (ret < 0) {
1374 		return dev_err_probe(dev, ret, "Failed to get AVDD voltage\n");
1375 	}
1376 
1377 	avdd_mv = ret == -ENODEV || ret == -EINVAL ? 0 : ret / MILLI;
1378 
1379 	ret = devm_regulator_get_enable(dev, "dvdd");
1380 	if (ret)
1381 		return dev_err_probe(dev, ret, "Failed to enable specified DVdd supply\n");
1382 
1383 	/*
1384 	 * This is either REFIN1 or REFIN2 depending on adi,refin2-pins-enable.
1385 	 * If this supply is not present, fall back to AVDD as reference.
1386 	 */
1387 	ret = devm_regulator_get_enable_read_voltage(dev, "vref");
1388 	if (ret == -ENODEV) {
1389 		if (avdd_mv == 0)
1390 			return dev_err_probe(dev, -ENODEV,
1391 					     "No reference voltage available\n");
1392 	} else if (ret < 0) {
1393 		return ret;
1394 	}
1395 
1396 	st->int_vref_mv = ret == -ENODEV ? avdd_mv : ret / MILLI;
1397 
1398 	st->chip_info = spi_get_device_match_data(spi);
1399 	if (!st->chip_info)
1400 		return -ENODEV;
1401 
1402 	indio_dev->name = st->chip_info->name;
1403 	indio_dev->modes = INDIO_DIRECT_MODE;
1404 	indio_dev->info = st->chip_info->info;
1405 	if (st->chip_info->parse_channels) {
1406 		ret = st->chip_info->parse_channels(indio_dev);
1407 		if (ret)
1408 			return ret;
1409 	} else {
1410 		indio_dev->channels = st->chip_info->channels;
1411 		indio_dev->num_channels = st->chip_info->num_channels;
1412 	}
1413 
1414 	ret = ad_sd_init(&st->sd, indio_dev, spi, st->chip_info->sigma_delta_info);
1415 	if (ret)
1416 		return ret;
1417 
1418 	ret = devm_ad_sd_setup_buffer_and_trigger(dev, indio_dev);
1419 	if (ret)
1420 		return ret;
1421 
1422 	ret = ad7192_clock_setup(st);
1423 	if (ret)
1424 		return ret;
1425 
1426 	ret = ad7192_setup(indio_dev, dev);
1427 	if (ret)
1428 		return ret;
1429 
1430 	return devm_iio_device_register(dev, indio_dev);
1431 }
1432 
1433 static const struct of_device_id ad7192_of_match[] = {
1434 	{ .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] },
1435 	{ .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] },
1436 	{ .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] },
1437 	{ .compatible = "adi,ad7194", .data = &ad7192_chip_info_tbl[ID_AD7194] },
1438 	{ .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] },
1439 	{ }
1440 };
1441 MODULE_DEVICE_TABLE(of, ad7192_of_match);
1442 
1443 static const struct spi_device_id ad7192_ids[] = {
1444 	{ "ad7190", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7190] },
1445 	{ "ad7192", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7192] },
1446 	{ "ad7193", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7193] },
1447 	{ "ad7194", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7194] },
1448 	{ "ad7195", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7195] },
1449 	{ }
1450 };
1451 MODULE_DEVICE_TABLE(spi, ad7192_ids);
1452 
1453 static struct spi_driver ad7192_driver = {
1454 	.driver = {
1455 		.name	= "ad7192",
1456 		.of_match_table = ad7192_of_match,
1457 	},
1458 	.probe		= ad7192_probe,
1459 	.id_table	= ad7192_ids,
1460 };
1461 module_spi_driver(ad7192_driver);
1462 
1463 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1464 MODULE_DESCRIPTION("Analog Devices AD7192 and similar ADC");
1465 MODULE_LICENSE("GPL v2");
1466 MODULE_IMPORT_NS("IIO_AD_SIGMA_DELTA");
1467