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 	if (!iio_device_claim_direct(indio_dev))
260 		return -EBUSY;
261 
262 	temp = st->syscalib_mode[chan->channel];
263 	if (sys_calib) {
264 		if (temp == AD7192_SYSCALIB_ZERO_SCALE)
265 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_ZERO,
266 					      chan->address);
267 		else
268 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_FULL,
269 					      chan->address);
270 	}
271 
272 	iio_device_release_direct(indio_dev);
273 
274 	return ret ? ret : len;
275 }
276 
277 static const struct iio_enum ad7192_syscalib_mode_enum = {
278 	.items = ad7192_syscalib_modes,
279 	.num_items = ARRAY_SIZE(ad7192_syscalib_modes),
280 	.set = ad7192_set_syscalib_mode,
281 	.get = ad7192_get_syscalib_mode
282 };
283 
284 static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = {
285 	{
286 		.name = "sys_calibration",
287 		.write = ad7192_write_syscalib,
288 		.shared = IIO_SEPARATE,
289 	},
290 	IIO_ENUM("sys_calibration_mode", IIO_SEPARATE,
291 		 &ad7192_syscalib_mode_enum),
292 	IIO_ENUM_AVAILABLE("sys_calibration_mode", IIO_SHARED_BY_TYPE,
293 			   &ad7192_syscalib_mode_enum),
294 	{ }
295 };
296 
ad_sigma_delta_to_ad7192(struct ad_sigma_delta * sd)297 static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd)
298 {
299 	return container_of(sd, struct ad7192_state, sd);
300 }
301 
ad7192_set_channel(struct ad_sigma_delta * sd,unsigned int channel)302 static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
303 {
304 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
305 
306 	st->conf &= ~AD7192_CONF_CHAN_MASK;
307 	st->conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, channel);
308 
309 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
310 }
311 
ad7192_set_mode(struct ad_sigma_delta * sd,enum ad_sigma_delta_mode mode)312 static int ad7192_set_mode(struct ad_sigma_delta *sd,
313 			   enum ad_sigma_delta_mode mode)
314 {
315 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
316 
317 	st->mode &= ~AD7192_MODE_SEL_MASK;
318 	st->mode |= FIELD_PREP(AD7192_MODE_SEL_MASK, mode);
319 
320 	return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
321 }
322 
ad7192_append_status(struct ad_sigma_delta * sd,bool append)323 static int ad7192_append_status(struct ad_sigma_delta *sd, bool append)
324 {
325 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
326 	unsigned int mode = st->mode;
327 	int ret;
328 
329 	mode &= ~AD7192_MODE_STA_MASK;
330 	mode |= FIELD_PREP(AD7192_MODE_STA_MASK, append);
331 
332 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, mode);
333 	if (ret < 0)
334 		return ret;
335 
336 	st->mode = mode;
337 
338 	return 0;
339 }
340 
ad7192_disable_all(struct ad_sigma_delta * sd)341 static int ad7192_disable_all(struct ad_sigma_delta *sd)
342 {
343 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
344 	u32 conf = st->conf;
345 	int ret;
346 
347 	conf &= ~AD7192_CONF_CHAN_MASK;
348 
349 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
350 	if (ret < 0)
351 		return ret;
352 
353 	st->conf = conf;
354 
355 	return 0;
356 }
357 
358 static const struct ad_sigma_delta_info ad7192_sigma_delta_info = {
359 	.set_channel = ad7192_set_channel,
360 	.append_status = ad7192_append_status,
361 	.disable_all = ad7192_disable_all,
362 	.set_mode = ad7192_set_mode,
363 	.has_registers = true,
364 	.addr_shift = 3,
365 	.read_mask = BIT(6),
366 	.status_ch_mask = GENMASK(3, 0),
367 	.num_slots = 4,
368 	.irq_flags = IRQF_TRIGGER_FALLING,
369 	.num_resetclks = 40,
370 };
371 
372 static const struct ad_sigma_delta_info ad7194_sigma_delta_info = {
373 	.set_channel = ad7192_set_channel,
374 	.append_status = ad7192_append_status,
375 	.disable_all = ad7192_disable_all,
376 	.set_mode = ad7192_set_mode,
377 	.has_registers = true,
378 	.addr_shift = 3,
379 	.read_mask = BIT(6),
380 	.status_ch_mask = GENMASK(3, 0),
381 	.irq_flags = IRQF_TRIGGER_FALLING,
382 	.num_resetclks = 40,
383 };
384 
385 static const struct ad_sd_calib_data ad7192_calib_arr[8] = {
386 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
387 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
388 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
389 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
390 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
391 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
392 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
393 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
394 };
395 
ad7192_calibrate_all(struct ad7192_state * st)396 static int ad7192_calibrate_all(struct ad7192_state *st)
397 {
398 	return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr,
399 				   ARRAY_SIZE(ad7192_calib_arr));
400 }
401 
ad7192_valid_external_frequency(u32 freq)402 static inline bool ad7192_valid_external_frequency(u32 freq)
403 {
404 	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
405 		freq <= AD7192_EXT_FREQ_MHZ_MAX);
406 }
407 
408 /*
409  * Position 0 of ad7192_clock_names, xtal, corresponds to clock source
410  * configuration AD7192_CLK_EXT_MCLK1_2 and position 1, mclk, corresponds to
411  * AD7192_CLK_EXT_MCLK2
412  */
413 static const char *const ad7192_clock_names[] = {
414 	"xtal",
415 	"mclk"
416 };
417 
clk_hw_to_ad7192(struct clk_hw * hw)418 static struct ad7192_state *clk_hw_to_ad7192(struct clk_hw *hw)
419 {
420 	return container_of(hw, struct ad7192_state, int_clk_hw);
421 }
422 
ad7192_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)423 static unsigned long ad7192_clk_recalc_rate(struct clk_hw *hw,
424 					    unsigned long parent_rate)
425 {
426 	return AD7192_INT_FREQ_MHZ;
427 }
428 
ad7192_clk_output_is_enabled(struct clk_hw * hw)429 static int ad7192_clk_output_is_enabled(struct clk_hw *hw)
430 {
431 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
432 
433 	return st->clock_sel == AD7192_CLK_INT_CO;
434 }
435 
ad7192_clk_prepare(struct clk_hw * hw)436 static int ad7192_clk_prepare(struct clk_hw *hw)
437 {
438 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
439 	int ret;
440 
441 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
442 	st->mode |= AD7192_CLK_INT_CO;
443 
444 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
445 	if (ret)
446 		return ret;
447 
448 	st->clock_sel = AD7192_CLK_INT_CO;
449 
450 	return 0;
451 }
452 
ad7192_clk_unprepare(struct clk_hw * hw)453 static void ad7192_clk_unprepare(struct clk_hw *hw)
454 {
455 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
456 	int ret;
457 
458 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
459 	st->mode |= AD7192_CLK_INT;
460 
461 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
462 	if (ret)
463 		return;
464 
465 	st->clock_sel = AD7192_CLK_INT;
466 }
467 
468 static const struct clk_ops ad7192_int_clk_ops = {
469 	.recalc_rate = ad7192_clk_recalc_rate,
470 	.is_enabled = ad7192_clk_output_is_enabled,
471 	.prepare = ad7192_clk_prepare,
472 	.unprepare = ad7192_clk_unprepare,
473 };
474 
ad7192_register_clk_provider(struct ad7192_state * st)475 static int ad7192_register_clk_provider(struct ad7192_state *st)
476 {
477 	struct device *dev = &st->sd.spi->dev;
478 	struct clk_init_data init = {};
479 	int ret;
480 
481 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
482 		return 0;
483 
484 	if (!device_property_present(dev, "#clock-cells"))
485 		return 0;
486 
487 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk",
488 				   fwnode_get_name(dev_fwnode(dev)));
489 	if (!init.name)
490 		return -ENOMEM;
491 
492 	init.ops = &ad7192_int_clk_ops;
493 
494 	st->int_clk_hw.init = &init;
495 	ret = devm_clk_hw_register(dev, &st->int_clk_hw);
496 	if (ret)
497 		return ret;
498 
499 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
500 					   &st->int_clk_hw);
501 }
502 
ad7192_clock_setup(struct ad7192_state * st)503 static int ad7192_clock_setup(struct ad7192_state *st)
504 {
505 	struct device *dev = &st->sd.spi->dev;
506 	int ret;
507 
508 	/*
509 	 * The following two if branches are kept for backward compatibility but
510 	 * the use of the two devicetree properties is highly discouraged. Clock
511 	 * configuration should be done according to the bindings.
512 	 */
513 
514 	if (device_property_read_bool(dev, "adi,int-clock-output-enable")) {
515 		st->clock_sel = AD7192_CLK_INT_CO;
516 		st->fclk = AD7192_INT_FREQ_MHZ;
517 		dev_warn(dev, "Property adi,int-clock-output-enable is deprecated! Check bindings!\n");
518 		return 0;
519 	}
520 
521 	if (device_property_read_bool(dev, "adi,clock-xtal")) {
522 		st->clock_sel = AD7192_CLK_EXT_MCLK1_2;
523 		st->mclk = devm_clk_get_enabled(dev, "mclk");
524 		if (IS_ERR(st->mclk))
525 			return dev_err_probe(dev, PTR_ERR(st->mclk),
526 					     "Failed to get mclk\n");
527 
528 		st->fclk = clk_get_rate(st->mclk);
529 		if (!ad7192_valid_external_frequency(st->fclk))
530 			return dev_err_probe(dev, -EINVAL,
531 					     "External clock frequency out of bounds\n");
532 
533 		dev_warn(dev, "Property adi,clock-xtal is deprecated! Check bindings!\n");
534 		return 0;
535 	}
536 
537 	ret = device_property_match_property_string(dev, "clock-names",
538 						    ad7192_clock_names,
539 						    ARRAY_SIZE(ad7192_clock_names));
540 	if (ret < 0) {
541 		st->clock_sel = AD7192_CLK_INT;
542 		st->fclk = AD7192_INT_FREQ_MHZ;
543 
544 		ret = ad7192_register_clk_provider(st);
545 		if (ret)
546 			return dev_err_probe(dev, ret,
547 					     "Failed to register clock provider\n");
548 		return 0;
549 	}
550 
551 	st->clock_sel = AD7192_CLK_EXT_MCLK1_2 + ret;
552 
553 	st->mclk = devm_clk_get_enabled(dev, ad7192_clock_names[ret]);
554 	if (IS_ERR(st->mclk))
555 		return dev_err_probe(dev, PTR_ERR(st->mclk),
556 				     "Failed to get clock source\n");
557 
558 	st->fclk = clk_get_rate(st->mclk);
559 	if (!ad7192_valid_external_frequency(st->fclk))
560 		return dev_err_probe(dev, -EINVAL,
561 				     "External clock frequency out of bounds\n");
562 
563 	return 0;
564 }
565 
ad7192_setup(struct iio_dev * indio_dev,struct device * dev)566 static int ad7192_setup(struct iio_dev *indio_dev, struct device *dev)
567 {
568 	struct ad7192_state *st = iio_priv(indio_dev);
569 	bool rej60_en, refin2_en;
570 	bool buf_en, bipolar, burnout_curr_en;
571 	unsigned long long scale_uv;
572 	int i, ret, id;
573 
574 	/* reset the serial interface */
575 	ret = ad_sd_reset(&st->sd);
576 	if (ret < 0)
577 		return ret;
578 	usleep_range(500, 1000); /* Wait for at least 500us */
579 
580 	/* write/read test for device presence */
581 	ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id);
582 	if (ret)
583 		return ret;
584 
585 	id = FIELD_GET(AD7192_ID_MASK, id);
586 
587 	if (id != st->chip_info->chip_id)
588 		dev_warn(dev, "device ID query failed (0x%X != 0x%X)\n",
589 			 id, st->chip_info->chip_id);
590 
591 	st->mode = FIELD_PREP(AD7192_MODE_SEL_MASK, AD7192_MODE_IDLE) |
592 		FIELD_PREP(AD7192_MODE_CLKSRC_MASK, st->clock_sel) |
593 		FIELD_PREP(AD7192_MODE_RATE_MASK, 480);
594 
595 	st->conf = FIELD_PREP(AD7192_CONF_GAIN_MASK, 0);
596 
597 	rej60_en = device_property_read_bool(dev, "adi,rejection-60-Hz-enable");
598 	if (rej60_en)
599 		st->mode |= AD7192_MODE_REJ60;
600 
601 	refin2_en = device_property_read_bool(dev, "adi,refin2-pins-enable");
602 	if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195)
603 		st->conf |= AD7192_CONF_REFSEL;
604 
605 	st->conf &= ~AD7192_CONF_CHOP;
606 
607 	buf_en = device_property_read_bool(dev, "adi,buffer-enable");
608 	if (buf_en)
609 		st->conf |= AD7192_CONF_BUF;
610 
611 	bipolar = device_property_read_bool(dev, "bipolar");
612 	if (!bipolar)
613 		st->conf |= AD7192_CONF_UNIPOLAR;
614 
615 	burnout_curr_en = device_property_read_bool(dev,
616 						    "adi,burnout-currents-enable");
617 	if (burnout_curr_en && buf_en) {
618 		st->conf |= AD7192_CONF_BURN;
619 	} else if (burnout_curr_en) {
620 		dev_warn(dev,
621 			 "Can't enable burnout currents: see CHOP or buffer\n");
622 	}
623 
624 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
625 	if (ret)
626 		return ret;
627 
628 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
629 	if (ret)
630 		return ret;
631 
632 	ret = ad7192_calibrate_all(st);
633 	if (ret)
634 		return ret;
635 
636 	/* Populate available ADC input ranges */
637 	for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
638 		scale_uv = ((u64)st->int_vref_mv * 100000000)
639 			>> (indio_dev->channels[0].scan_type.realbits -
640 			!FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf));
641 		scale_uv >>= i;
642 
643 		st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
644 		st->scale_avail[i][0] = scale_uv;
645 	}
646 
647 	st->oversampling_ratio_avail[0] = 1;
648 	st->oversampling_ratio_avail[1] = 2;
649 	st->oversampling_ratio_avail[2] = 8;
650 	st->oversampling_ratio_avail[3] = 16;
651 
652 	st->filter_freq_avail[0][0] = 600;
653 	st->filter_freq_avail[1][0] = 800;
654 	st->filter_freq_avail[2][0] = 2300;
655 	st->filter_freq_avail[3][0] = 2720;
656 
657 	st->filter_freq_avail[0][1] = 1000;
658 	st->filter_freq_avail[1][1] = 1000;
659 	st->filter_freq_avail[2][1] = 1000;
660 	st->filter_freq_avail[3][1] = 1000;
661 
662 	return 0;
663 }
664 
ad7192_show_ac_excitation(struct device * dev,struct device_attribute * attr,char * buf)665 static ssize_t ad7192_show_ac_excitation(struct device *dev,
666 					 struct device_attribute *attr,
667 					 char *buf)
668 {
669 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
670 	struct ad7192_state *st = iio_priv(indio_dev);
671 
672 	return sysfs_emit(buf, "%ld\n", FIELD_GET(AD7192_CONF_ACX, st->conf));
673 }
674 
ad7192_show_bridge_switch(struct device * dev,struct device_attribute * attr,char * buf)675 static ssize_t ad7192_show_bridge_switch(struct device *dev,
676 					 struct device_attribute *attr,
677 					 char *buf)
678 {
679 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
680 	struct ad7192_state *st = iio_priv(indio_dev);
681 
682 	return sysfs_emit(buf, "%ld\n",
683 			  FIELD_GET(AD7192_GPOCON_BPDSW, st->gpocon));
684 }
685 
ad7192_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)686 static ssize_t ad7192_set(struct device *dev,
687 			  struct device_attribute *attr,
688 			  const char *buf,
689 			  size_t len)
690 {
691 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
692 	struct ad7192_state *st = iio_priv(indio_dev);
693 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
694 	int ret;
695 	bool val;
696 
697 	ret = kstrtobool(buf, &val);
698 	if (ret < 0)
699 		return ret;
700 
701 	ret = iio_device_claim_direct_mode(indio_dev);
702 	if (ret)
703 		return ret;
704 
705 	switch ((u32)this_attr->address) {
706 	case AD7192_REG_GPOCON:
707 		if (val)
708 			st->gpocon |= AD7192_GPOCON_BPDSW;
709 		else
710 			st->gpocon &= ~AD7192_GPOCON_BPDSW;
711 
712 		ad_sd_write_reg(&st->sd, AD7192_REG_GPOCON, 1, st->gpocon);
713 		break;
714 	case AD7192_REG_CONF:
715 		if (val)
716 			st->conf |= AD7192_CONF_ACX;
717 		else
718 			st->conf &= ~AD7192_CONF_ACX;
719 
720 		ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
721 		break;
722 	default:
723 		ret = -EINVAL;
724 	}
725 
726 	iio_device_release_direct_mode(indio_dev);
727 
728 	return ret ? ret : len;
729 }
730 
ad7192_compute_f_order(struct ad7192_state * st,bool sinc3_en,bool chop_en)731 static int ad7192_compute_f_order(struct ad7192_state *st, bool sinc3_en, bool chop_en)
732 {
733 	u8 avg_factor_selected, oversampling_ratio;
734 
735 	avg_factor_selected = FIELD_GET(AD7192_MODE_AVG_MASK, st->mode);
736 
737 	if (!avg_factor_selected && !chop_en)
738 		return 1;
739 
740 	oversampling_ratio = st->oversampling_ratio_avail[avg_factor_selected];
741 
742 	if (sinc3_en)
743 		return AD7192_SYNC3_FILTER + oversampling_ratio - 1;
744 
745 	return AD7192_SYNC4_FILTER + oversampling_ratio - 1;
746 }
747 
ad7192_get_f_order(struct ad7192_state * st)748 static int ad7192_get_f_order(struct ad7192_state *st)
749 {
750 	bool sinc3_en, chop_en;
751 
752 	sinc3_en = FIELD_GET(AD7192_MODE_SINC3, st->mode);
753 	chop_en = FIELD_GET(AD7192_CONF_CHOP, st->conf);
754 
755 	return ad7192_compute_f_order(st, sinc3_en, chop_en);
756 }
757 
ad7192_compute_f_adc(struct ad7192_state * st,bool sinc3_en,bool chop_en)758 static int ad7192_compute_f_adc(struct ad7192_state *st, bool sinc3_en,
759 				bool chop_en)
760 {
761 	unsigned int f_order = ad7192_compute_f_order(st, sinc3_en, chop_en);
762 
763 	return DIV_ROUND_CLOSEST(st->fclk,
764 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
765 }
766 
ad7192_get_f_adc(struct ad7192_state * st)767 static int ad7192_get_f_adc(struct ad7192_state *st)
768 {
769 	unsigned int f_order = ad7192_get_f_order(st);
770 
771 	return DIV_ROUND_CLOSEST(st->fclk,
772 				 f_order * FIELD_GET(AD7192_MODE_RATE_MASK, st->mode));
773 }
774 
ad7192_update_filter_freq_avail(struct ad7192_state * st)775 static void ad7192_update_filter_freq_avail(struct ad7192_state *st)
776 {
777 	unsigned int fadc;
778 
779 	/* Formulas for filter at page 25 of the datasheet */
780 	fadc = ad7192_compute_f_adc(st, false, true);
781 	st->filter_freq_avail[0][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
782 
783 	fadc = ad7192_compute_f_adc(st, true, true);
784 	st->filter_freq_avail[1][0] = DIV_ROUND_CLOSEST(fadc * 240, 1024);
785 
786 	fadc = ad7192_compute_f_adc(st, false, false);
787 	st->filter_freq_avail[2][0] = DIV_ROUND_CLOSEST(fadc * 230, 1024);
788 
789 	fadc = ad7192_compute_f_adc(st, true, false);
790 	st->filter_freq_avail[3][0] = DIV_ROUND_CLOSEST(fadc * 272, 1024);
791 }
792 
793 static IIO_DEVICE_ATTR(bridge_switch_en, 0644,
794 		       ad7192_show_bridge_switch, ad7192_set,
795 		       AD7192_REG_GPOCON);
796 
797 static IIO_DEVICE_ATTR(ac_excitation_en, 0644,
798 		       ad7192_show_ac_excitation, ad7192_set,
799 		       AD7192_REG_CONF);
800 
801 static struct attribute *ad7192_attributes[] = {
802 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
803 	NULL
804 };
805 
806 static const struct attribute_group ad7192_attribute_group = {
807 	.attrs = ad7192_attributes,
808 };
809 
810 static struct attribute *ad7195_attributes[] = {
811 	&iio_dev_attr_bridge_switch_en.dev_attr.attr,
812 	&iio_dev_attr_ac_excitation_en.dev_attr.attr,
813 	NULL
814 };
815 
816 static const struct attribute_group ad7195_attribute_group = {
817 	.attrs = ad7195_attributes,
818 };
819 
ad7192_get_temp_scale(bool unipolar)820 static unsigned int ad7192_get_temp_scale(bool unipolar)
821 {
822 	return unipolar ? 2815 * 2 : 2815;
823 }
824 
ad7192_set_3db_filter_freq(struct ad7192_state * st,int val,int val2)825 static int ad7192_set_3db_filter_freq(struct ad7192_state *st,
826 				      int val, int val2)
827 {
828 	int i, ret, freq;
829 	unsigned int diff_new, diff_old;
830 	int idx = 0;
831 
832 	diff_old = U32_MAX;
833 	freq = val * 1000 + val2;
834 
835 	for (i = 0; i < ARRAY_SIZE(st->filter_freq_avail); i++) {
836 		diff_new = abs(freq - st->filter_freq_avail[i][0]);
837 		if (diff_new < diff_old) {
838 			diff_old = diff_new;
839 			idx = i;
840 		}
841 	}
842 
843 	switch (idx) {
844 	case 0:
845 		st->mode &= ~AD7192_MODE_SINC3;
846 
847 		st->conf |= AD7192_CONF_CHOP;
848 		break;
849 	case 1:
850 		st->mode |= AD7192_MODE_SINC3;
851 
852 		st->conf |= AD7192_CONF_CHOP;
853 		break;
854 	case 2:
855 		st->mode &= ~AD7192_MODE_SINC3;
856 
857 		st->conf &= ~AD7192_CONF_CHOP;
858 		break;
859 	case 3:
860 		st->mode |= AD7192_MODE_SINC3;
861 
862 		st->conf &= ~AD7192_CONF_CHOP;
863 		break;
864 	}
865 
866 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
867 	if (ret < 0)
868 		return ret;
869 
870 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
871 }
872 
ad7192_get_3db_filter_freq(struct ad7192_state * st)873 static int ad7192_get_3db_filter_freq(struct ad7192_state *st)
874 {
875 	unsigned int fadc;
876 
877 	fadc = ad7192_get_f_adc(st);
878 
879 	if (FIELD_GET(AD7192_CONF_CHOP, st->conf))
880 		return DIV_ROUND_CLOSEST(fadc * 240, 1024);
881 	if (FIELD_GET(AD7192_MODE_SINC3, st->mode))
882 		return DIV_ROUND_CLOSEST(fadc * 272, 1024);
883 	else
884 		return DIV_ROUND_CLOSEST(fadc * 230, 1024);
885 }
886 
ad7192_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)887 static int ad7192_read_raw(struct iio_dev *indio_dev,
888 			   struct iio_chan_spec const *chan,
889 			   int *val,
890 			   int *val2,
891 			   long m)
892 {
893 	struct ad7192_state *st = iio_priv(indio_dev);
894 	bool unipolar = FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf);
895 	u8 gain = FIELD_GET(AD7192_CONF_GAIN_MASK, st->conf);
896 
897 	switch (m) {
898 	case IIO_CHAN_INFO_RAW:
899 		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
900 	case IIO_CHAN_INFO_SCALE:
901 		switch (chan->type) {
902 		case IIO_VOLTAGE:
903 			mutex_lock(&st->lock);
904 			*val = st->scale_avail[gain][0];
905 			*val2 = st->scale_avail[gain][1];
906 			mutex_unlock(&st->lock);
907 			return IIO_VAL_INT_PLUS_NANO;
908 		case IIO_TEMP:
909 			*val = 0;
910 			*val2 = 1000000000 / ad7192_get_temp_scale(unipolar);
911 			return IIO_VAL_INT_PLUS_NANO;
912 		default:
913 			return -EINVAL;
914 		}
915 	case IIO_CHAN_INFO_OFFSET:
916 		if (!unipolar)
917 			*val = -(1 << (chan->scan_type.realbits - 1));
918 		else
919 			*val = 0;
920 
921 		switch (chan->type) {
922 		case IIO_VOLTAGE:
923 			/*
924 			 * Only applies to pseudo-differential inputs.
925 			 * AINCOM voltage has to be converted to "raw" units.
926 			 */
927 			if (st->aincom_mv && !chan->differential)
928 				*val += DIV_ROUND_CLOSEST_ULL((u64)st->aincom_mv * NANO,
929 							      st->scale_avail[gain][1]);
930 			return IIO_VAL_INT;
931 		/* Kelvin to Celsius */
932 		case IIO_TEMP:
933 			*val -= 273 * ad7192_get_temp_scale(unipolar);
934 			return IIO_VAL_INT;
935 		default:
936 			return -EINVAL;
937 		}
938 	case IIO_CHAN_INFO_SAMP_FREQ:
939 		*val = DIV_ROUND_CLOSEST(ad7192_get_f_adc(st), 1024);
940 		return IIO_VAL_INT;
941 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
942 		*val = ad7192_get_3db_filter_freq(st);
943 		*val2 = 1000;
944 		return IIO_VAL_FRACTIONAL;
945 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
946 		*val = st->oversampling_ratio_avail[FIELD_GET(AD7192_MODE_AVG_MASK, st->mode)];
947 		return IIO_VAL_INT;
948 	}
949 
950 	return -EINVAL;
951 }
952 
ad7192_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)953 static int ad7192_write_raw(struct iio_dev *indio_dev,
954 			    struct iio_chan_spec const *chan,
955 			    int val,
956 			    int val2,
957 			    long mask)
958 {
959 	struct ad7192_state *st = iio_priv(indio_dev);
960 	int ret, i, div;
961 	unsigned int tmp;
962 
963 	ret = iio_device_claim_direct_mode(indio_dev);
964 	if (ret)
965 		return ret;
966 
967 	mutex_lock(&st->lock);
968 
969 	switch (mask) {
970 	case IIO_CHAN_INFO_SCALE:
971 		ret = -EINVAL;
972 		for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++)
973 			if (val2 == st->scale_avail[i][1]) {
974 				ret = 0;
975 				tmp = st->conf;
976 				st->conf &= ~AD7192_CONF_GAIN_MASK;
977 				st->conf |= FIELD_PREP(AD7192_CONF_GAIN_MASK, i);
978 				if (tmp == st->conf)
979 					break;
980 				ad_sd_write_reg(&st->sd, AD7192_REG_CONF,
981 						3, st->conf);
982 				ad7192_calibrate_all(st);
983 				break;
984 			}
985 		break;
986 	case IIO_CHAN_INFO_SAMP_FREQ:
987 		if (!val) {
988 			ret = -EINVAL;
989 			break;
990 		}
991 
992 		div = st->fclk / (val * ad7192_get_f_order(st) * 1024);
993 		if (div < 1 || div > 1023) {
994 			ret = -EINVAL;
995 			break;
996 		}
997 
998 		st->mode &= ~AD7192_MODE_RATE_MASK;
999 		st->mode |= FIELD_PREP(AD7192_MODE_RATE_MASK, div);
1000 		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
1001 		ad7192_update_filter_freq_avail(st);
1002 		break;
1003 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1004 		ret = ad7192_set_3db_filter_freq(st, val, val2 / 1000);
1005 		break;
1006 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1007 		ret = -EINVAL;
1008 		for (i = 0; i < ARRAY_SIZE(st->oversampling_ratio_avail); i++)
1009 			if (val == st->oversampling_ratio_avail[i]) {
1010 				ret = 0;
1011 				tmp = st->mode;
1012 				st->mode &= ~AD7192_MODE_AVG_MASK;
1013 				st->mode |= FIELD_PREP(AD7192_MODE_AVG_MASK, i);
1014 				if (tmp == st->mode)
1015 					break;
1016 				ad_sd_write_reg(&st->sd, AD7192_REG_MODE,
1017 						3, st->mode);
1018 				break;
1019 			}
1020 		ad7192_update_filter_freq_avail(st);
1021 		break;
1022 	default:
1023 		ret = -EINVAL;
1024 	}
1025 
1026 	mutex_unlock(&st->lock);
1027 
1028 	iio_device_release_direct_mode(indio_dev);
1029 
1030 	return ret;
1031 }
1032 
ad7192_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)1033 static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
1034 				    struct iio_chan_spec const *chan,
1035 				    long mask)
1036 {
1037 	switch (mask) {
1038 	case IIO_CHAN_INFO_SCALE:
1039 		return IIO_VAL_INT_PLUS_NANO;
1040 	case IIO_CHAN_INFO_SAMP_FREQ:
1041 		return IIO_VAL_INT;
1042 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1043 		return IIO_VAL_INT_PLUS_MICRO;
1044 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1045 		return IIO_VAL_INT;
1046 	default:
1047 		return -EINVAL;
1048 	}
1049 }
1050 
ad7192_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)1051 static int ad7192_read_avail(struct iio_dev *indio_dev,
1052 			     struct iio_chan_spec const *chan,
1053 			     const int **vals, int *type, int *length,
1054 			     long mask)
1055 {
1056 	struct ad7192_state *st = iio_priv(indio_dev);
1057 
1058 	switch (mask) {
1059 	case IIO_CHAN_INFO_SCALE:
1060 		*vals = (int *)st->scale_avail;
1061 		*type = IIO_VAL_INT_PLUS_NANO;
1062 		/* Values are stored in a 2D matrix  */
1063 		*length = ARRAY_SIZE(st->scale_avail) * 2;
1064 
1065 		return IIO_AVAIL_LIST;
1066 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1067 		*vals = (int *)st->filter_freq_avail;
1068 		*type = IIO_VAL_FRACTIONAL;
1069 		*length = ARRAY_SIZE(st->filter_freq_avail) * 2;
1070 
1071 		return IIO_AVAIL_LIST;
1072 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1073 		*vals = (int *)st->oversampling_ratio_avail;
1074 		*type = IIO_VAL_INT;
1075 		*length = ARRAY_SIZE(st->oversampling_ratio_avail);
1076 
1077 		return IIO_AVAIL_LIST;
1078 	}
1079 
1080 	return -EINVAL;
1081 }
1082 
ad7192_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)1083 static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask)
1084 {
1085 	struct ad7192_state *st = iio_priv(indio_dev);
1086 	u32 conf = st->conf;
1087 	int ret;
1088 	int i;
1089 
1090 	conf &= ~AD7192_CONF_CHAN_MASK;
1091 	for_each_set_bit(i, scan_mask, 8)
1092 		conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, BIT(i));
1093 
1094 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
1095 	if (ret < 0)
1096 		return ret;
1097 
1098 	st->conf = conf;
1099 
1100 	return 0;
1101 }
1102 
1103 static const struct iio_info ad7192_info = {
1104 	.read_raw = ad7192_read_raw,
1105 	.write_raw = ad7192_write_raw,
1106 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1107 	.read_avail = ad7192_read_avail,
1108 	.attrs = &ad7192_attribute_group,
1109 	.validate_trigger = ad_sd_validate_trigger,
1110 	.update_scan_mode = ad7192_update_scan_mode,
1111 };
1112 
1113 static const struct iio_info ad7194_info = {
1114 	.read_raw = ad7192_read_raw,
1115 	.write_raw = ad7192_write_raw,
1116 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1117 	.read_avail = ad7192_read_avail,
1118 	.validate_trigger = ad_sd_validate_trigger,
1119 };
1120 
1121 static const struct iio_info ad7195_info = {
1122 	.read_raw = ad7192_read_raw,
1123 	.write_raw = ad7192_write_raw,
1124 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1125 	.read_avail = ad7192_read_avail,
1126 	.attrs = &ad7195_attribute_group,
1127 	.validate_trigger = ad_sd_validate_trigger,
1128 	.update_scan_mode = ad7192_update_scan_mode,
1129 };
1130 
1131 #define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _type, \
1132 	_mask_all, _mask_type_av, _mask_all_av, _ext_info) \
1133 	{ \
1134 		.type = (_type), \
1135 		.differential = ((_channel2) == -1 ? 0 : 1), \
1136 		.indexed = 1, \
1137 		.channel = (_channel1), \
1138 		.channel2 = (_channel2), \
1139 		.address = (_address), \
1140 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1141 			BIT(IIO_CHAN_INFO_OFFSET), \
1142 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
1143 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
1144 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1145 			(_mask_all), \
1146 		.info_mask_shared_by_type_available = (_mask_type_av), \
1147 		.info_mask_shared_by_all_available = \
1148 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1149 			(_mask_all_av), \
1150 		.ext_info = (_ext_info), \
1151 		.scan_index = (_si), \
1152 		.scan_type = { \
1153 			.sign = 'u', \
1154 			.realbits = 24, \
1155 			.storagebits = 32, \
1156 			.endianness = IIO_BE, \
1157 		}, \
1158 	}
1159 
1160 #define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1161 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, IIO_VOLTAGE, 0, \
1162 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1163 
1164 #define AD719x_CHANNEL(_si, _channel1, _address) \
1165 	__AD719x_CHANNEL(_si, _channel1, -1, _address, IIO_VOLTAGE, 0, \
1166 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1167 
1168 #define AD719x_TEMP_CHANNEL(_si, _address) \
1169 	__AD719x_CHANNEL(_si, 0, -1, _address, IIO_TEMP, 0, 0, 0, NULL)
1170 
1171 #define AD7193_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1172 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, \
1173 		IIO_VOLTAGE, \
1174 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1175 		BIT(IIO_CHAN_INFO_SCALE), \
1176 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1177 		ad7192_calibsys_ext_info)
1178 
1179 #define AD7193_CHANNEL(_si, _channel1, _address) \
1180 	AD7193_DIFF_CHANNEL(_si, _channel1, -1, _address)
1181 
1182 static const struct iio_chan_spec ad7192_channels[] = {
1183 	AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
1184 	AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
1185 	AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
1186 	AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M),
1187 	AD719x_CHANNEL(4, 1, AD7192_CH_AIN1),
1188 	AD719x_CHANNEL(5, 2, AD7192_CH_AIN2),
1189 	AD719x_CHANNEL(6, 3, AD7192_CH_AIN3),
1190 	AD719x_CHANNEL(7, 4, AD7192_CH_AIN4),
1191 	IIO_CHAN_SOFT_TIMESTAMP(8),
1192 };
1193 
1194 static const struct iio_chan_spec ad7193_channels[] = {
1195 	AD7193_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
1196 	AD7193_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
1197 	AD7193_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
1198 	AD7193_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M),
1199 	AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP),
1200 	AD7193_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M),
1201 	AD7193_CHANNEL(6, 1, AD7193_CH_AIN1),
1202 	AD7193_CHANNEL(7, 2, AD7193_CH_AIN2),
1203 	AD7193_CHANNEL(8, 3, AD7193_CH_AIN3),
1204 	AD7193_CHANNEL(9, 4, AD7193_CH_AIN4),
1205 	AD7193_CHANNEL(10, 5, AD7193_CH_AIN5),
1206 	AD7193_CHANNEL(11, 6, AD7193_CH_AIN6),
1207 	AD7193_CHANNEL(12, 7, AD7193_CH_AIN7),
1208 	AD7193_CHANNEL(13, 8, AD7193_CH_AIN8),
1209 	IIO_CHAN_SOFT_TIMESTAMP(14),
1210 };
1211 
ad7194_validate_ain_channel(struct device * dev,u32 ain)1212 static bool ad7194_validate_ain_channel(struct device *dev, u32 ain)
1213 {
1214 	return in_range(ain, AD7194_CH_AIN_START, AD7194_CH_AIN_NR);
1215 }
1216 
ad7194_parse_channels(struct iio_dev * indio_dev)1217 static int ad7194_parse_channels(struct iio_dev *indio_dev)
1218 {
1219 	struct device *dev = indio_dev->dev.parent;
1220 	struct iio_chan_spec *ad7194_channels;
1221 	const struct iio_chan_spec ad7194_chan = AD7193_CHANNEL(0, 0, 0);
1222 	const struct iio_chan_spec ad7194_chan_diff = AD7193_DIFF_CHANNEL(0, 0, 0, 0);
1223 	const struct iio_chan_spec ad7194_chan_temp = AD719x_TEMP_CHANNEL(0, 0);
1224 	const struct iio_chan_spec ad7194_chan_timestamp = IIO_CHAN_SOFT_TIMESTAMP(0);
1225 	unsigned int num_channels, index = 0;
1226 	u32 ain[2];
1227 	int ret;
1228 
1229 	num_channels = device_get_child_node_count(dev);
1230 	if (num_channels > AD7194_CH_MAX_NR)
1231 		return dev_err_probe(dev, -EINVAL, "Too many channels: %u\n",
1232 				     num_channels);
1233 
1234 	num_channels += AD7194_CH_BASE_NR;
1235 
1236 	ad7194_channels = devm_kcalloc(dev, num_channels,
1237 				       sizeof(*ad7194_channels), GFP_KERNEL);
1238 	if (!ad7194_channels)
1239 		return -ENOMEM;
1240 
1241 	indio_dev->channels = ad7194_channels;
1242 	indio_dev->num_channels = num_channels;
1243 
1244 	device_for_each_child_node_scoped(dev, child) {
1245 		ret = fwnode_property_read_u32_array(child, "diff-channels",
1246 						     ain, ARRAY_SIZE(ain));
1247 		if (ret == 0) {
1248 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1249 				return dev_err_probe(dev, -EINVAL,
1250 						     "Invalid AIN channel: %u\n",
1251 						     ain[0]);
1252 
1253 			if (!ad7194_validate_ain_channel(dev, ain[1]))
1254 				return dev_err_probe(dev, -EINVAL,
1255 						     "Invalid AIN channel: %u\n",
1256 						     ain[1]);
1257 
1258 			*ad7194_channels = ad7194_chan_diff;
1259 			ad7194_channels->scan_index = index++;
1260 			ad7194_channels->channel = ain[0];
1261 			ad7194_channels->channel2 = ain[1];
1262 			ad7194_channels->address = AD7194_DIFF_CH(ain[0], ain[1]);
1263 		} else {
1264 			ret = fwnode_property_read_u32(child, "single-channel",
1265 						       &ain[0]);
1266 			if (ret)
1267 				return dev_err_probe(dev, ret,
1268 						     "Missing channel property\n");
1269 
1270 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1271 				return dev_err_probe(dev, -EINVAL,
1272 						     "Invalid AIN channel: %u\n",
1273 						     ain[0]);
1274 
1275 			*ad7194_channels = ad7194_chan;
1276 			ad7194_channels->scan_index = index++;
1277 			ad7194_channels->channel = ain[0];
1278 			ad7194_channels->address = AD7194_CH(ain[0]);
1279 		}
1280 		ad7194_channels++;
1281 	}
1282 
1283 	*ad7194_channels = ad7194_chan_temp;
1284 	ad7194_channels->scan_index = index++;
1285 	ad7194_channels->address = AD7194_CH_TEMP;
1286 	ad7194_channels++;
1287 
1288 	*ad7194_channels = ad7194_chan_timestamp;
1289 	ad7194_channels->scan_index = index;
1290 
1291 	return 0;
1292 }
1293 
1294 static const struct ad7192_chip_info ad7192_chip_info_tbl[] = {
1295 	[ID_AD7190] = {
1296 		.chip_id = CHIPID_AD7190,
1297 		.name = "ad7190",
1298 		.channels = ad7192_channels,
1299 		.num_channels = ARRAY_SIZE(ad7192_channels),
1300 		.sigma_delta_info = &ad7192_sigma_delta_info,
1301 		.info = &ad7192_info,
1302 	},
1303 	[ID_AD7192] = {
1304 		.chip_id = CHIPID_AD7192,
1305 		.name = "ad7192",
1306 		.channels = ad7192_channels,
1307 		.num_channels = ARRAY_SIZE(ad7192_channels),
1308 		.sigma_delta_info = &ad7192_sigma_delta_info,
1309 		.info = &ad7192_info,
1310 	},
1311 	[ID_AD7193] = {
1312 		.chip_id = CHIPID_AD7193,
1313 		.name = "ad7193",
1314 		.channels = ad7193_channels,
1315 		.num_channels = ARRAY_SIZE(ad7193_channels),
1316 		.sigma_delta_info = &ad7192_sigma_delta_info,
1317 		.info = &ad7192_info,
1318 	},
1319 	[ID_AD7194] = {
1320 		.chip_id = CHIPID_AD7194,
1321 		.name = "ad7194",
1322 		.info = &ad7194_info,
1323 		.sigma_delta_info = &ad7194_sigma_delta_info,
1324 		.parse_channels = ad7194_parse_channels,
1325 	},
1326 	[ID_AD7195] = {
1327 		.chip_id = CHIPID_AD7195,
1328 		.name = "ad7195",
1329 		.channels = ad7192_channels,
1330 		.num_channels = ARRAY_SIZE(ad7192_channels),
1331 		.sigma_delta_info = &ad7192_sigma_delta_info,
1332 		.info = &ad7195_info,
1333 	},
1334 };
1335 
ad7192_probe(struct spi_device * spi)1336 static int ad7192_probe(struct spi_device *spi)
1337 {
1338 	struct device *dev = &spi->dev;
1339 	struct ad7192_state *st;
1340 	struct iio_dev *indio_dev;
1341 	int ret, avdd_mv;
1342 
1343 	if (!spi->irq)
1344 		return dev_err_probe(dev, -ENODEV, "Failed to get IRQ\n");
1345 
1346 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1347 	if (!indio_dev)
1348 		return -ENOMEM;
1349 
1350 	st = iio_priv(indio_dev);
1351 
1352 	mutex_init(&st->lock);
1353 
1354 	/*
1355 	 * Regulator aincom is optional to maintain compatibility with older DT.
1356 	 * Newer firmware should provide a zero volt fixed supply if wired to
1357 	 * ground.
1358 	 */
1359 	ret = devm_regulator_get_enable_read_voltage(dev, "aincom");
1360 	if (ret < 0 && ret != -ENODEV)
1361 		return dev_err_probe(dev, ret, "Failed to get AINCOM voltage\n");
1362 
1363 	st->aincom_mv = ret == -ENODEV ? 0 : ret / MILLI;
1364 
1365 	/* AVDD can optionally be used as reference voltage */
1366 	ret = devm_regulator_get_enable_read_voltage(dev, "avdd");
1367 	if (ret == -ENODEV || ret == -EINVAL) {
1368 		int ret2;
1369 
1370 		/*
1371 		 * We get -EINVAL if avdd is a supply with unknown voltage. We
1372 		 * still need to enable it since it is also a power supply.
1373 		 */
1374 		ret2 = devm_regulator_get_enable(dev, "avdd");
1375 		if (ret2)
1376 			return dev_err_probe(dev, ret2,
1377 					     "Failed to enable AVDD supply\n");
1378 	} else if (ret < 0) {
1379 		return dev_err_probe(dev, ret, "Failed to get AVDD voltage\n");
1380 	}
1381 
1382 	avdd_mv = ret == -ENODEV || ret == -EINVAL ? 0 : ret / MILLI;
1383 
1384 	ret = devm_regulator_get_enable(dev, "dvdd");
1385 	if (ret)
1386 		return dev_err_probe(dev, ret, "Failed to enable specified DVdd supply\n");
1387 
1388 	/*
1389 	 * This is either REFIN1 or REFIN2 depending on adi,refin2-pins-enable.
1390 	 * If this supply is not present, fall back to AVDD as reference.
1391 	 */
1392 	ret = devm_regulator_get_enable_read_voltage(dev, "vref");
1393 	if (ret == -ENODEV) {
1394 		if (avdd_mv == 0)
1395 			return dev_err_probe(dev, -ENODEV,
1396 					     "No reference voltage available\n");
1397 	} else if (ret < 0) {
1398 		return ret;
1399 	}
1400 
1401 	st->int_vref_mv = ret == -ENODEV ? avdd_mv : ret / MILLI;
1402 
1403 	st->chip_info = spi_get_device_match_data(spi);
1404 	if (!st->chip_info)
1405 		return -ENODEV;
1406 
1407 	indio_dev->name = st->chip_info->name;
1408 	indio_dev->modes = INDIO_DIRECT_MODE;
1409 	indio_dev->info = st->chip_info->info;
1410 	if (st->chip_info->parse_channels) {
1411 		ret = st->chip_info->parse_channels(indio_dev);
1412 		if (ret)
1413 			return ret;
1414 	} else {
1415 		indio_dev->channels = st->chip_info->channels;
1416 		indio_dev->num_channels = st->chip_info->num_channels;
1417 	}
1418 
1419 	ret = ad_sd_init(&st->sd, indio_dev, spi, st->chip_info->sigma_delta_info);
1420 	if (ret)
1421 		return ret;
1422 
1423 	ret = devm_ad_sd_setup_buffer_and_trigger(dev, indio_dev);
1424 	if (ret)
1425 		return ret;
1426 
1427 	ret = ad7192_clock_setup(st);
1428 	if (ret)
1429 		return ret;
1430 
1431 	ret = ad7192_setup(indio_dev, dev);
1432 	if (ret)
1433 		return ret;
1434 
1435 	return devm_iio_device_register(dev, indio_dev);
1436 }
1437 
1438 static const struct of_device_id ad7192_of_match[] = {
1439 	{ .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] },
1440 	{ .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] },
1441 	{ .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] },
1442 	{ .compatible = "adi,ad7194", .data = &ad7192_chip_info_tbl[ID_AD7194] },
1443 	{ .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] },
1444 	{ }
1445 };
1446 MODULE_DEVICE_TABLE(of, ad7192_of_match);
1447 
1448 static const struct spi_device_id ad7192_ids[] = {
1449 	{ "ad7190", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7190] },
1450 	{ "ad7192", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7192] },
1451 	{ "ad7193", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7193] },
1452 	{ "ad7194", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7194] },
1453 	{ "ad7195", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7195] },
1454 	{ }
1455 };
1456 MODULE_DEVICE_TABLE(spi, ad7192_ids);
1457 
1458 static struct spi_driver ad7192_driver = {
1459 	.driver = {
1460 		.name	= "ad7192",
1461 		.of_match_table = ad7192_of_match,
1462 	},
1463 	.probe		= ad7192_probe,
1464 	.id_table	= ad7192_ids,
1465 };
1466 module_spi_driver(ad7192_driver);
1467 
1468 MODULE_AUTHOR("Michael Hennerich <[email protected]>");
1469 MODULE_DESCRIPTION("Analog Devices AD7192 and similar ADC");
1470 MODULE_LICENSE("GPL v2");
1471 MODULE_IMPORT_NS("IIO_AD_SIGMA_DELTA");
1472