xref: /linux/drivers/iio/adc/ad7192.c (revision df02351331671abb26788bc13f6d276e26ae068f)
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/cleanup.h>
11 #include <linux/clk.h>
12 #include <linux/clk-provider.h>
13 #include <linux/device.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/sysfs.h>
17 #include <linux/spi/spi.h>
18 #include <linux/regulator/consumer.h>
19 #include <linux/err.h>
20 #include <linux/sched.h>
21 #include <linux/delay.h>
22 #include <linux/module.h>
23 #include <linux/mod_devicetable.h>
24 #include <linux/property.h>
25 #include <linux/units.h>
26 
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/trigger.h>
31 #include <linux/iio/trigger_consumer.h>
32 #include <linux/iio/triggered_buffer.h>
33 #include <linux/iio/adc/ad_sigma_delta.h>
34 
35 /* Registers */
36 #define AD7192_REG_COMM		0 /* Communications Register (WO, 8-bit) */
37 #define AD7192_REG_STAT		0 /* Status Register	     (RO, 8-bit) */
38 #define AD7192_REG_MODE		1 /* Mode Register	     (RW, 24-bit */
39 #define AD7192_REG_CONF		2 /* Configuration Register  (RW, 24-bit) */
40 #define AD7192_REG_DATA		3 /* Data Register	     (RO, 24/32-bit) */
41 #define AD7192_REG_ID		4 /* ID Register	     (RO, 8-bit) */
42 #define AD7192_REG_GPOCON	5 /* GPOCON Register	     (RO, 8-bit) */
43 #define AD7192_REG_OFFSET	6 /* Offset Register	     (RW, 16-bit */
44 				  /* (AD7792)/24-bit (AD7192)) */
45 #define AD7192_REG_FULLSALE	7 /* Full-Scale Register */
46 				  /* (RW, 16-bit (AD7792)/24-bit (AD7192)) */
47 
48 /* Communications Register Bit Designations (AD7192_REG_COMM) */
49 #define AD7192_COMM_WEN		BIT(7) /* Write Enable */
50 #define AD7192_COMM_WRITE	0 /* Write Operation */
51 #define AD7192_COMM_READ	BIT(6) /* Read Operation */
52 #define AD7192_COMM_ADDR_MASK	GENMASK(5, 3) /* Register Address Mask */
53 #define AD7192_COMM_CREAD	BIT(2) /* Continuous Read of Data Register */
54 
55 /* Status Register Bit Designations (AD7192_REG_STAT) */
56 #define AD7192_STAT_RDY		BIT(7) /* Ready */
57 #define AD7192_STAT_ERR		BIT(6) /* Error (Overrange, Underrange) */
58 #define AD7192_STAT_NOREF	BIT(5) /* Error no external reference */
59 #define AD7192_STAT_PARITY	BIT(4) /* Parity */
60 #define AD7192_STAT_CH3		BIT(2) /* Channel 3 */
61 #define AD7192_STAT_CH2		BIT(1) /* Channel 2 */
62 #define AD7192_STAT_CH1		BIT(0) /* Channel 1 */
63 
64 /* Mode Register Bit Designations (AD7192_REG_MODE) */
65 #define AD7192_MODE_SEL_MASK	GENMASK(23, 21) /* Operation Mode Select Mask */
66 #define AD7192_MODE_STA_MASK	BIT(20) /* Status Register transmission Mask */
67 #define AD7192_MODE_CLKSRC_MASK	GENMASK(19, 18) /* Clock Source Select Mask */
68 #define AD7192_MODE_AVG_MASK	GENMASK(17, 16)
69 		  /* Fast Settling Filter Average Select Mask (AD7193 only) */
70 #define AD7192_MODE_SINC3	BIT(15) /* SINC3 Filter Select */
71 #define AD7192_MODE_ENPAR	BIT(13) /* Parity Enable */
72 #define AD7192_MODE_CLKDIV	BIT(12) /* Clock divide by 2 (AD7190/2 only)*/
73 #define AD7192_MODE_SCYCLE	BIT(11) /* Single cycle conversion */
74 #define AD7192_MODE_REJ60	BIT(10) /* 50/60Hz notch filter */
75 				  /* Filter Update Rate Select Mask */
76 #define AD7192_MODE_RATE_MASK	GENMASK(9, 0)
77 
78 /* Mode Register: AD7192_MODE_SEL options */
79 #define AD7192_MODE_CONT		0 /* Continuous Conversion Mode */
80 #define AD7192_MODE_SINGLE		1 /* Single Conversion Mode */
81 #define AD7192_MODE_IDLE		2 /* Idle Mode */
82 #define AD7192_MODE_PWRDN		3 /* Power-Down Mode */
83 #define AD7192_MODE_CAL_INT_ZERO	4 /* Internal Zero-Scale Calibration */
84 #define AD7192_MODE_CAL_INT_FULL	5 /* Internal Full-Scale Calibration */
85 #define AD7192_MODE_CAL_SYS_ZERO	6 /* System Zero-Scale Calibration */
86 #define AD7192_MODE_CAL_SYS_FULL	7 /* System Full-Scale Calibration */
87 
88 /* Mode Register: AD7192_MODE_CLKSRC options */
89 #define AD7192_CLK_EXT_MCLK1_2		0 /* External 4.92 MHz Clock connected*/
90 					  /* from MCLK1 to MCLK2 */
91 #define AD7192_CLK_EXT_MCLK2		1 /* External Clock applied to MCLK2 */
92 #define AD7192_CLK_INT			2 /* Internal 4.92 MHz Clock not */
93 					  /* available at the MCLK2 pin */
94 #define AD7192_CLK_INT_CO		3 /* Internal 4.92 MHz Clock available*/
95 					  /* at the MCLK2 pin */
96 
97 /* Configuration Register Bit Designations (AD7192_REG_CONF) */
98 
99 #define AD7192_CONF_CHOP	BIT(23) /* CHOP enable */
100 #define AD7192_CONF_ACX		BIT(22) /* AC excitation enable(AD7195 only) */
101 #define AD7192_CONF_REFSEL	BIT(20) /* REFIN1/REFIN2 Reference Select */
102 #define AD7192_CONF_CHAN_MASK	GENMASK(18, 8) /* Channel select mask */
103 #define AD7192_CONF_BURN	BIT(7) /* Burnout current enable */
104 #define AD7192_CONF_REFDET	BIT(6) /* Reference detect enable */
105 #define AD7192_CONF_BUF		BIT(4) /* Buffered Mode Enable */
106 #define AD7192_CONF_UNIPOLAR	BIT(3) /* Unipolar/Bipolar Enable */
107 #define AD7192_CONF_GAIN_MASK	GENMASK(2, 0) /* Gain Select */
108 
109 #define AD7192_CH_AIN1P_AIN2M	BIT(0) /* AIN1(+) - AIN2(-) */
110 #define AD7192_CH_AIN3P_AIN4M	BIT(1) /* AIN3(+) - AIN4(-) */
111 #define AD7192_CH_TEMP		BIT(2) /* Temp Sensor */
112 #define AD7192_CH_AIN2P_AIN2M	BIT(3) /* AIN2(+) - AIN2(-) */
113 #define AD7192_CH_AIN1		BIT(4) /* AIN1 - AINCOM */
114 #define AD7192_CH_AIN2		BIT(5) /* AIN2 - AINCOM */
115 #define AD7192_CH_AIN3		BIT(6) /* AIN3 - AINCOM */
116 #define AD7192_CH_AIN4		BIT(7) /* AIN4 - AINCOM */
117 
118 #define AD7193_CH_AIN1P_AIN2M	0x001  /* AIN1(+) - AIN2(-) */
119 #define AD7193_CH_AIN3P_AIN4M	0x002  /* AIN3(+) - AIN4(-) */
120 #define AD7193_CH_AIN5P_AIN6M	0x004  /* AIN5(+) - AIN6(-) */
121 #define AD7193_CH_AIN7P_AIN8M	0x008  /* AIN7(+) - AIN8(-) */
122 #define AD7193_CH_TEMP		0x100 /* Temp senseor */
123 #define AD7193_CH_AIN2P_AIN2M	0x200 /* AIN2(+) - AIN2(-) */
124 #define AD7193_CH_AIN1		0x401 /* AIN1 - AINCOM */
125 #define AD7193_CH_AIN2		0x402 /* AIN2 - AINCOM */
126 #define AD7193_CH_AIN3		0x404 /* AIN3 - AINCOM */
127 #define AD7193_CH_AIN4		0x408 /* AIN4 - AINCOM */
128 #define AD7193_CH_AIN5		0x410 /* AIN5 - AINCOM */
129 #define AD7193_CH_AIN6		0x420 /* AIN6 - AINCOM */
130 #define AD7193_CH_AIN7		0x440 /* AIN7 - AINCOM */
131 #define AD7193_CH_AIN8		0x480 /* AIN7 - AINCOM */
132 #define AD7193_CH_AINCOM	0x600 /* AINCOM - AINCOM */
133 
134 #define AD7194_CH_POS(x)	(((x) - 1) << 4)
135 #define AD7194_CH_NEG(x)	((x) - 1)
136 
137 /* 10th bit corresponds to CON18(Pseudo) */
138 #define AD7194_CH(p)		(BIT(10) | AD7194_CH_POS(p))
139 
140 #define AD7194_DIFF_CH(p, n)	(AD7194_CH_POS(p) | AD7194_CH_NEG(n))
141 #define AD7194_CH_TEMP		0x100
142 #define AD7194_CH_BASE_NR	2
143 #define AD7194_CH_AIN_START	1
144 #define AD7194_CH_AIN_NR	16
145 #define AD7194_CH_MAX_NR	272
146 
147 /* ID Register Bit Designations (AD7192_REG_ID) */
148 #define CHIPID_AD7190		0x4
149 #define CHIPID_AD7192		0x0
150 #define CHIPID_AD7193		0x2
151 #define CHIPID_AD7194		0x3
152 #define CHIPID_AD7195		0x6
153 #define AD7192_ID_MASK		GENMASK(3, 0)
154 
155 /* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */
156 #define AD7192_GPOCON_BPDSW	BIT(6) /* Bridge power-down switch enable */
157 #define AD7192_GPOCON_GP32EN	BIT(5) /* Digital Output P3 and P2 enable */
158 #define AD7192_GPOCON_GP10EN	BIT(4) /* Digital Output P1 and P0 enable */
159 #define AD7192_GPOCON_P3DAT	BIT(3) /* P3 state */
160 #define AD7192_GPOCON_P2DAT	BIT(2) /* P2 state */
161 #define AD7192_GPOCON_P1DAT	BIT(1) /* P1 state */
162 #define AD7192_GPOCON_P0DAT	BIT(0) /* P0 state */
163 
164 #define AD7192_EXT_FREQ_MHZ_MIN	2457600
165 #define AD7192_EXT_FREQ_MHZ_MAX	5120000
166 #define AD7192_INT_FREQ_MHZ	4915200
167 
168 #define AD7192_NO_SYNC_FILTER	1
169 #define AD7192_SYNC3_FILTER	3
170 #define AD7192_SYNC4_FILTER	4
171 
172 /* NOTE:
173  * The AD7190/2/5 features a dual use data out ready DOUT/RDY output.
174  * In order to avoid contentions on the SPI bus, it's therefore necessary
175  * to use spi bus locking.
176  *
177  * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
178  */
179 
180 enum {
181 	AD7192_SYSCALIB_ZERO_SCALE,
182 	AD7192_SYSCALIB_FULL_SCALE,
183 };
184 
185 enum {
186 	ID_AD7190,
187 	ID_AD7192,
188 	ID_AD7193,
189 	ID_AD7194,
190 	ID_AD7195,
191 };
192 
193 struct ad7192_chip_info {
194 	unsigned int			chip_id;
195 	const char			*name;
196 	const struct iio_chan_spec	*channels;
197 	u8				num_channels;
198 	const struct ad_sigma_delta_info	*sigma_delta_info;
199 	const struct iio_info		*info;
200 	int (*parse_channels)(struct iio_dev *indio_dev);
201 };
202 
203 struct ad7192_state {
204 	const struct ad7192_chip_info	*chip_info;
205 	struct clk			*mclk;
206 	struct clk_hw			int_clk_hw;
207 	u16				int_vref_mv;
208 	u32				aincom_mv;
209 	u32				fclk;
210 	u32				mode;
211 	u32				conf;
212 	u32				scale_avail[8][2];
213 	u32				filter_freq_avail[4][2];
214 	u32				oversampling_ratio_avail[4];
215 	u8				gpocon;
216 	u8				clock_sel;
217 	struct mutex			lock;	/* protect sensor state */
218 	u8				syscalib_mode[8];
219 
220 	struct ad_sigma_delta		sd;
221 };
222 
223 static const char * const ad7192_syscalib_modes[] = {
224 	[AD7192_SYSCALIB_ZERO_SCALE] = "zero_scale",
225 	[AD7192_SYSCALIB_FULL_SCALE] = "full_scale",
226 };
227 
ad7192_set_syscalib_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int mode)228 static int ad7192_set_syscalib_mode(struct iio_dev *indio_dev,
229 				    const struct iio_chan_spec *chan,
230 				    unsigned int mode)
231 {
232 	struct ad7192_state *st = iio_priv(indio_dev);
233 
234 	st->syscalib_mode[chan->channel] = mode;
235 
236 	return 0;
237 }
238 
ad7192_get_syscalib_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)239 static int ad7192_get_syscalib_mode(struct iio_dev *indio_dev,
240 				    const struct iio_chan_spec *chan)
241 {
242 	struct ad7192_state *st = iio_priv(indio_dev);
243 
244 	return st->syscalib_mode[chan->channel];
245 }
246 
ad7192_write_syscalib(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)247 static ssize_t ad7192_write_syscalib(struct iio_dev *indio_dev,
248 				     uintptr_t private,
249 				     const struct iio_chan_spec *chan,
250 				     const char *buf, size_t len)
251 {
252 	struct ad7192_state *st = iio_priv(indio_dev);
253 	bool sys_calib;
254 	int ret, temp;
255 
256 	ret = kstrtobool(buf, &sys_calib);
257 	if (ret)
258 		return ret;
259 
260 	if (!iio_device_claim_direct(indio_dev))
261 		return -EBUSY;
262 
263 	temp = st->syscalib_mode[chan->channel];
264 	if (sys_calib) {
265 		if (temp == AD7192_SYSCALIB_ZERO_SCALE)
266 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_ZERO,
267 					      chan->address);
268 		else
269 			ret = ad_sd_calibrate(&st->sd, AD7192_MODE_CAL_SYS_FULL,
270 					      chan->address);
271 	}
272 
273 	iio_device_release_direct(indio_dev);
274 
275 	return ret ? ret : len;
276 }
277 
278 static const struct iio_enum ad7192_syscalib_mode_enum = {
279 	.items = ad7192_syscalib_modes,
280 	.num_items = ARRAY_SIZE(ad7192_syscalib_modes),
281 	.set = ad7192_set_syscalib_mode,
282 	.get = ad7192_get_syscalib_mode
283 };
284 
285 static const struct iio_chan_spec_ext_info ad7192_calibsys_ext_info[] = {
286 	{
287 		.name = "sys_calibration",
288 		.write = ad7192_write_syscalib,
289 		.shared = IIO_SEPARATE,
290 	},
291 	IIO_ENUM("sys_calibration_mode", IIO_SEPARATE,
292 		 &ad7192_syscalib_mode_enum),
293 	IIO_ENUM_AVAILABLE("sys_calibration_mode", IIO_SHARED_BY_TYPE,
294 			   &ad7192_syscalib_mode_enum),
295 	{ }
296 };
297 
ad_sigma_delta_to_ad7192(struct ad_sigma_delta * sd)298 static struct ad7192_state *ad_sigma_delta_to_ad7192(struct ad_sigma_delta *sd)
299 {
300 	return container_of(sd, struct ad7192_state, sd);
301 }
302 
ad7192_set_channel(struct ad_sigma_delta * sd,unsigned int channel)303 static int ad7192_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
304 {
305 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
306 
307 	st->conf &= ~AD7192_CONF_CHAN_MASK;
308 	st->conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, channel);
309 
310 	return ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
311 }
312 
ad7192_set_mode(struct ad_sigma_delta * sd,enum ad_sigma_delta_mode mode)313 static int ad7192_set_mode(struct ad_sigma_delta *sd,
314 			   enum ad_sigma_delta_mode mode)
315 {
316 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
317 
318 	st->mode &= ~AD7192_MODE_SEL_MASK;
319 	st->mode |= FIELD_PREP(AD7192_MODE_SEL_MASK, mode);
320 
321 	return ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
322 }
323 
ad7192_append_status(struct ad_sigma_delta * sd,bool append)324 static int ad7192_append_status(struct ad_sigma_delta *sd, bool append)
325 {
326 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
327 	unsigned int mode = st->mode;
328 	int ret;
329 
330 	mode &= ~AD7192_MODE_STA_MASK;
331 	mode |= FIELD_PREP(AD7192_MODE_STA_MASK, append);
332 
333 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, mode);
334 	if (ret < 0)
335 		return ret;
336 
337 	st->mode = mode;
338 
339 	return 0;
340 }
341 
ad7192_disable_all(struct ad_sigma_delta * sd)342 static int ad7192_disable_all(struct ad_sigma_delta *sd)
343 {
344 	struct ad7192_state *st = ad_sigma_delta_to_ad7192(sd);
345 	u32 conf = st->conf;
346 	int ret;
347 
348 	conf &= ~AD7192_CONF_CHAN_MASK;
349 
350 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
351 	if (ret < 0)
352 		return ret;
353 
354 	st->conf = conf;
355 
356 	return 0;
357 }
358 
359 static const struct ad_sigma_delta_info ad7192_sigma_delta_info = {
360 	.set_channel = ad7192_set_channel,
361 	.append_status = ad7192_append_status,
362 	.disable_all = ad7192_disable_all,
363 	.set_mode = ad7192_set_mode,
364 	.has_registers = true,
365 	.addr_shift = 3,
366 	.read_mask = BIT(6),
367 	.status_ch_mask = GENMASK(3, 0),
368 	.num_slots = 4,
369 	.irq_flags = IRQF_TRIGGER_FALLING,
370 	.num_resetclks = 40,
371 };
372 
373 static const struct ad_sigma_delta_info ad7194_sigma_delta_info = {
374 	.set_channel = ad7192_set_channel,
375 	.append_status = ad7192_append_status,
376 	.disable_all = ad7192_disable_all,
377 	.set_mode = ad7192_set_mode,
378 	.has_registers = true,
379 	.addr_shift = 3,
380 	.read_mask = BIT(6),
381 	.status_ch_mask = GENMASK(3, 0),
382 	.irq_flags = IRQF_TRIGGER_FALLING,
383 	.num_resetclks = 40,
384 };
385 
386 static const struct ad_sd_calib_data ad7192_calib_arr[8] = {
387 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN1},
388 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN1},
389 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN2},
390 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN2},
391 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN3},
392 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN3},
393 	{AD7192_MODE_CAL_INT_ZERO, AD7192_CH_AIN4},
394 	{AD7192_MODE_CAL_INT_FULL, AD7192_CH_AIN4}
395 };
396 
ad7192_calibrate_all(struct ad7192_state * st)397 static int ad7192_calibrate_all(struct ad7192_state *st)
398 {
399 	return ad_sd_calibrate_all(&st->sd, ad7192_calib_arr,
400 				   ARRAY_SIZE(ad7192_calib_arr));
401 }
402 
ad7192_valid_external_frequency(u32 freq)403 static inline bool ad7192_valid_external_frequency(u32 freq)
404 {
405 	return (freq >= AD7192_EXT_FREQ_MHZ_MIN &&
406 		freq <= AD7192_EXT_FREQ_MHZ_MAX);
407 }
408 
409 /*
410  * Position 0 of ad7192_clock_names, xtal, corresponds to clock source
411  * configuration AD7192_CLK_EXT_MCLK1_2 and position 1, mclk, corresponds to
412  * AD7192_CLK_EXT_MCLK2
413  */
414 static const char *const ad7192_clock_names[] = {
415 	"xtal",
416 	"mclk"
417 };
418 
clk_hw_to_ad7192(struct clk_hw * hw)419 static struct ad7192_state *clk_hw_to_ad7192(struct clk_hw *hw)
420 {
421 	return container_of(hw, struct ad7192_state, int_clk_hw);
422 }
423 
ad7192_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)424 static unsigned long ad7192_clk_recalc_rate(struct clk_hw *hw,
425 					    unsigned long parent_rate)
426 {
427 	return AD7192_INT_FREQ_MHZ;
428 }
429 
ad7192_clk_output_is_enabled(struct clk_hw * hw)430 static int ad7192_clk_output_is_enabled(struct clk_hw *hw)
431 {
432 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
433 
434 	return st->clock_sel == AD7192_CLK_INT_CO;
435 }
436 
ad7192_clk_prepare(struct clk_hw * hw)437 static int ad7192_clk_prepare(struct clk_hw *hw)
438 {
439 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
440 	int ret;
441 
442 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
443 	st->mode |= AD7192_CLK_INT_CO;
444 
445 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
446 	if (ret)
447 		return ret;
448 
449 	st->clock_sel = AD7192_CLK_INT_CO;
450 
451 	return 0;
452 }
453 
ad7192_clk_unprepare(struct clk_hw * hw)454 static void ad7192_clk_unprepare(struct clk_hw *hw)
455 {
456 	struct ad7192_state *st = clk_hw_to_ad7192(hw);
457 	int ret;
458 
459 	st->mode &= ~AD7192_MODE_CLKSRC_MASK;
460 	st->mode |= AD7192_CLK_INT;
461 
462 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
463 	if (ret)
464 		return;
465 
466 	st->clock_sel = AD7192_CLK_INT;
467 }
468 
469 static const struct clk_ops ad7192_int_clk_ops = {
470 	.recalc_rate = ad7192_clk_recalc_rate,
471 	.is_enabled = ad7192_clk_output_is_enabled,
472 	.prepare = ad7192_clk_prepare,
473 	.unprepare = ad7192_clk_unprepare,
474 };
475 
ad7192_register_clk_provider(struct ad7192_state * st)476 static int ad7192_register_clk_provider(struct ad7192_state *st)
477 {
478 	struct device *dev = &st->sd.spi->dev;
479 	struct clk_init_data init = {};
480 	int ret;
481 
482 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
483 		return 0;
484 
485 	if (!device_property_present(dev, "#clock-cells"))
486 		return 0;
487 
488 	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-clk",
489 				   fwnode_get_name(dev_fwnode(dev)));
490 	if (!init.name)
491 		return -ENOMEM;
492 
493 	init.ops = &ad7192_int_clk_ops;
494 
495 	st->int_clk_hw.init = &init;
496 	ret = devm_clk_hw_register(dev, &st->int_clk_hw);
497 	if (ret)
498 		return ret;
499 
500 	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
501 					   &st->int_clk_hw);
502 }
503 
ad7192_clock_setup(struct ad7192_state * st)504 static int ad7192_clock_setup(struct ad7192_state *st)
505 {
506 	struct device *dev = &st->sd.spi->dev;
507 	int ret;
508 
509 	/*
510 	 * The following two if branches are kept for backward compatibility but
511 	 * the use of the two devicetree properties is highly discouraged. Clock
512 	 * configuration should be done according to the bindings.
513 	 */
514 
515 	if (device_property_read_bool(dev, "adi,int-clock-output-enable")) {
516 		st->clock_sel = AD7192_CLK_INT_CO;
517 		st->fclk = AD7192_INT_FREQ_MHZ;
518 		dev_warn(dev, "Property adi,int-clock-output-enable is deprecated! Check bindings!\n");
519 		return 0;
520 	}
521 
522 	if (device_property_read_bool(dev, "adi,clock-xtal")) {
523 		st->clock_sel = AD7192_CLK_EXT_MCLK1_2;
524 		st->mclk = devm_clk_get_enabled(dev, "mclk");
525 		if (IS_ERR(st->mclk))
526 			return dev_err_probe(dev, PTR_ERR(st->mclk),
527 					     "Failed to get mclk\n");
528 
529 		st->fclk = clk_get_rate(st->mclk);
530 		if (!ad7192_valid_external_frequency(st->fclk))
531 			return dev_err_probe(dev, -EINVAL,
532 					     "External clock frequency out of bounds\n");
533 
534 		dev_warn(dev, "Property adi,clock-xtal is deprecated! Check bindings!\n");
535 		return 0;
536 	}
537 
538 	ret = device_property_match_property_string(dev, "clock-names",
539 						    ad7192_clock_names,
540 						    ARRAY_SIZE(ad7192_clock_names));
541 	if (ret < 0) {
542 		st->clock_sel = AD7192_CLK_INT;
543 		st->fclk = AD7192_INT_FREQ_MHZ;
544 
545 		ret = ad7192_register_clk_provider(st);
546 		if (ret)
547 			return dev_err_probe(dev, ret,
548 					     "Failed to register clock provider\n");
549 		return 0;
550 	}
551 
552 	st->clock_sel = AD7192_CLK_EXT_MCLK1_2 + ret;
553 
554 	st->mclk = devm_clk_get_enabled(dev, ad7192_clock_names[ret]);
555 	if (IS_ERR(st->mclk))
556 		return dev_err_probe(dev, PTR_ERR(st->mclk),
557 				     "Failed to get clock source\n");
558 
559 	st->fclk = clk_get_rate(st->mclk);
560 	if (!ad7192_valid_external_frequency(st->fclk))
561 		return dev_err_probe(dev, -EINVAL,
562 				     "External clock frequency out of bounds\n");
563 
564 	return 0;
565 }
566 
ad7192_setup(struct iio_dev * indio_dev,struct device * dev)567 static int ad7192_setup(struct iio_dev *indio_dev, struct device *dev)
568 {
569 	struct ad7192_state *st = iio_priv(indio_dev);
570 	bool rej60_en, refin2_en;
571 	bool buf_en, bipolar, burnout_curr_en;
572 	unsigned long long scale_uv;
573 	int i, ret, id;
574 
575 	/* reset the serial interface */
576 	ret = ad_sd_reset(&st->sd);
577 	if (ret < 0)
578 		return ret;
579 	usleep_range(500, 1000); /* Wait for at least 500us */
580 
581 	/* write/read test for device presence */
582 	ret = ad_sd_read_reg(&st->sd, AD7192_REG_ID, 1, &id);
583 	if (ret)
584 		return ret;
585 
586 	id = FIELD_GET(AD7192_ID_MASK, id);
587 
588 	if (id != st->chip_info->chip_id)
589 		dev_warn(dev, "device ID query failed (0x%X != 0x%X)\n",
590 			 id, st->chip_info->chip_id);
591 
592 	st->mode = FIELD_PREP(AD7192_MODE_SEL_MASK, AD7192_MODE_IDLE) |
593 		FIELD_PREP(AD7192_MODE_CLKSRC_MASK, st->clock_sel) |
594 		FIELD_PREP(AD7192_MODE_RATE_MASK, 480);
595 
596 	st->conf = FIELD_PREP(AD7192_CONF_GAIN_MASK, 0);
597 
598 	rej60_en = device_property_read_bool(dev, "adi,rejection-60-Hz-enable");
599 	if (rej60_en)
600 		st->mode |= AD7192_MODE_REJ60;
601 
602 	refin2_en = device_property_read_bool(dev, "adi,refin2-pins-enable");
603 	if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195)
604 		st->conf |= AD7192_CONF_REFSEL;
605 
606 	st->conf &= ~AD7192_CONF_CHOP;
607 
608 	buf_en = device_property_read_bool(dev, "adi,buffer-enable");
609 	if (buf_en)
610 		st->conf |= AD7192_CONF_BUF;
611 
612 	bipolar = device_property_read_bool(dev, "bipolar");
613 	if (!bipolar)
614 		st->conf |= AD7192_CONF_UNIPOLAR;
615 
616 	burnout_curr_en = device_property_read_bool(dev,
617 						    "adi,burnout-currents-enable");
618 	if (burnout_curr_en && buf_en) {
619 		st->conf |= AD7192_CONF_BURN;
620 	} else if (burnout_curr_en) {
621 		dev_warn(dev,
622 			 "Can't enable burnout currents: see CHOP or buffer\n");
623 	}
624 
625 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
626 	if (ret)
627 		return ret;
628 
629 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
630 	if (ret)
631 		return ret;
632 
633 	ret = ad7192_calibrate_all(st);
634 	if (ret)
635 		return ret;
636 
637 	/* Populate available ADC input ranges */
638 	for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
639 		scale_uv = ((u64)st->int_vref_mv * 100000000)
640 			>> (indio_dev->channels[0].scan_type.realbits -
641 			!FIELD_GET(AD7192_CONF_UNIPOLAR, st->conf));
642 		scale_uv >>= i;
643 
644 		st->scale_avail[i][1] = do_div(scale_uv, 100000000) * 10;
645 		st->scale_avail[i][0] = scale_uv;
646 	}
647 
648 	st->oversampling_ratio_avail[0] = 1;
649 	st->oversampling_ratio_avail[1] = 2;
650 	st->oversampling_ratio_avail[2] = 8;
651 	st->oversampling_ratio_avail[3] = 16;
652 
653 	st->filter_freq_avail[0][0] = 600;
654 	st->filter_freq_avail[1][0] = 800;
655 	st->filter_freq_avail[2][0] = 2300;
656 	st->filter_freq_avail[3][0] = 2720;
657 
658 	st->filter_freq_avail[0][1] = 1000;
659 	st->filter_freq_avail[1][1] = 1000;
660 	st->filter_freq_avail[2][1] = 1000;
661 	st->filter_freq_avail[3][1] = 1000;
662 
663 	return 0;
664 }
665 
ad7192_show_ac_excitation(struct device * dev,struct device_attribute * attr,char * buf)666 static ssize_t ad7192_show_ac_excitation(struct device *dev,
667 					 struct device_attribute *attr,
668 					 char *buf)
669 {
670 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
671 	struct ad7192_state *st = iio_priv(indio_dev);
672 
673 	return sysfs_emit(buf, "%ld\n", FIELD_GET(AD7192_CONF_ACX, st->conf));
674 }
675 
ad7192_show_bridge_switch(struct device * dev,struct device_attribute * attr,char * buf)676 static ssize_t ad7192_show_bridge_switch(struct device *dev,
677 					 struct device_attribute *attr,
678 					 char *buf)
679 {
680 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
681 	struct ad7192_state *st = iio_priv(indio_dev);
682 
683 	return sysfs_emit(buf, "%ld\n",
684 			  FIELD_GET(AD7192_GPOCON_BPDSW, st->gpocon));
685 }
686 
ad7192_set(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)687 static ssize_t ad7192_set(struct device *dev,
688 			  struct device_attribute *attr,
689 			  const char *buf,
690 			  size_t len)
691 {
692 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
693 	struct ad7192_state *st = iio_priv(indio_dev);
694 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
695 	int ret;
696 	bool val;
697 
698 	ret = kstrtobool(buf, &val);
699 	if (ret < 0)
700 		return ret;
701 
702 	if (!iio_device_claim_direct(indio_dev))
703 		return -EBUSY;
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(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 i, div;
961 	unsigned int tmp;
962 
963 	guard(mutex)(&st->lock);
964 
965 	switch (mask) {
966 	case IIO_CHAN_INFO_SCALE:
967 		for (i = 0; i < ARRAY_SIZE(st->scale_avail); i++) {
968 			if (val2 != st->scale_avail[i][1])
969 				continue;
970 
971 			tmp = st->conf;
972 			st->conf &= ~AD7192_CONF_GAIN_MASK;
973 			st->conf |= FIELD_PREP(AD7192_CONF_GAIN_MASK, i);
974 			if (tmp == st->conf)
975 				return 0;
976 			ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, st->conf);
977 			ad7192_calibrate_all(st);
978 			return 0;
979 		}
980 		return -EINVAL;
981 	case IIO_CHAN_INFO_SAMP_FREQ:
982 		if (!val)
983 			return -EINVAL;
984 
985 		div = st->fclk / (val * ad7192_get_f_order(st) * 1024);
986 		if (div < 1 || div > 1023)
987 			return -EINVAL;
988 
989 		st->mode &= ~AD7192_MODE_RATE_MASK;
990 		st->mode |= FIELD_PREP(AD7192_MODE_RATE_MASK, div);
991 		ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
992 		ad7192_update_filter_freq_avail(st);
993 		return 0;
994 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
995 		return ad7192_set_3db_filter_freq(st, val, val2 / 1000);
996 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
997 		for (i = 0; i < ARRAY_SIZE(st->oversampling_ratio_avail); i++) {
998 			if (val != st->oversampling_ratio_avail[i])
999 				continue;
1000 
1001 			tmp = st->mode;
1002 			st->mode &= ~AD7192_MODE_AVG_MASK;
1003 			st->mode |= FIELD_PREP(AD7192_MODE_AVG_MASK, i);
1004 			if (tmp == st->mode)
1005 				return 0;
1006 			ad_sd_write_reg(&st->sd, AD7192_REG_MODE, 3, st->mode);
1007 			ad7192_update_filter_freq_avail(st);
1008 			return 0;
1009 		}
1010 		return -EINVAL;
1011 	default:
1012 		return -EINVAL;
1013 	}
1014 }
1015 
ad7192_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)1016 static int ad7192_write_raw(struct iio_dev *indio_dev,
1017 			    struct iio_chan_spec const *chan,
1018 			    int val,
1019 			    int val2,
1020 			    long mask)
1021 {
1022 	int ret;
1023 
1024 	if (!iio_device_claim_direct(indio_dev))
1025 		return -EBUSY;
1026 
1027 	ret = __ad7192_write_raw(indio_dev, chan, val, val2, mask);
1028 
1029 	iio_device_release_direct(indio_dev);
1030 
1031 	return ret;
1032 }
1033 
ad7192_write_raw_get_fmt(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,long mask)1034 static int ad7192_write_raw_get_fmt(struct iio_dev *indio_dev,
1035 				    struct iio_chan_spec const *chan,
1036 				    long mask)
1037 {
1038 	switch (mask) {
1039 	case IIO_CHAN_INFO_SCALE:
1040 		return IIO_VAL_INT_PLUS_NANO;
1041 	case IIO_CHAN_INFO_SAMP_FREQ:
1042 		return IIO_VAL_INT;
1043 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1044 		return IIO_VAL_INT_PLUS_MICRO;
1045 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1046 		return IIO_VAL_INT;
1047 	default:
1048 		return -EINVAL;
1049 	}
1050 }
1051 
ad7192_read_avail(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,const int ** vals,int * type,int * length,long mask)1052 static int ad7192_read_avail(struct iio_dev *indio_dev,
1053 			     struct iio_chan_spec const *chan,
1054 			     const int **vals, int *type, int *length,
1055 			     long mask)
1056 {
1057 	struct ad7192_state *st = iio_priv(indio_dev);
1058 
1059 	switch (mask) {
1060 	case IIO_CHAN_INFO_SCALE:
1061 		*vals = (int *)st->scale_avail;
1062 		*type = IIO_VAL_INT_PLUS_NANO;
1063 		/* Values are stored in a 2D matrix  */
1064 		*length = ARRAY_SIZE(st->scale_avail) * 2;
1065 
1066 		return IIO_AVAIL_LIST;
1067 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
1068 		*vals = (int *)st->filter_freq_avail;
1069 		*type = IIO_VAL_FRACTIONAL;
1070 		*length = ARRAY_SIZE(st->filter_freq_avail) * 2;
1071 
1072 		return IIO_AVAIL_LIST;
1073 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1074 		*vals = (int *)st->oversampling_ratio_avail;
1075 		*type = IIO_VAL_INT;
1076 		*length = ARRAY_SIZE(st->oversampling_ratio_avail);
1077 
1078 		return IIO_AVAIL_LIST;
1079 	}
1080 
1081 	return -EINVAL;
1082 }
1083 
ad7192_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)1084 static int ad7192_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask)
1085 {
1086 	struct ad7192_state *st = iio_priv(indio_dev);
1087 	u32 conf = st->conf;
1088 	int ret;
1089 	int i;
1090 
1091 	conf &= ~AD7192_CONF_CHAN_MASK;
1092 	for_each_set_bit(i, scan_mask, 8)
1093 		conf |= FIELD_PREP(AD7192_CONF_CHAN_MASK, BIT(i));
1094 
1095 	ret = ad_sd_write_reg(&st->sd, AD7192_REG_CONF, 3, conf);
1096 	if (ret < 0)
1097 		return ret;
1098 
1099 	st->conf = conf;
1100 
1101 	return 0;
1102 }
1103 
1104 static const struct iio_info ad7192_info = {
1105 	.read_raw = ad7192_read_raw,
1106 	.write_raw = ad7192_write_raw,
1107 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1108 	.read_avail = ad7192_read_avail,
1109 	.attrs = &ad7192_attribute_group,
1110 	.validate_trigger = ad_sd_validate_trigger,
1111 	.update_scan_mode = ad7192_update_scan_mode,
1112 };
1113 
1114 static const struct iio_info ad7194_info = {
1115 	.read_raw = ad7192_read_raw,
1116 	.write_raw = ad7192_write_raw,
1117 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1118 	.read_avail = ad7192_read_avail,
1119 	.validate_trigger = ad_sd_validate_trigger,
1120 };
1121 
1122 static const struct iio_info ad7195_info = {
1123 	.read_raw = ad7192_read_raw,
1124 	.write_raw = ad7192_write_raw,
1125 	.write_raw_get_fmt = ad7192_write_raw_get_fmt,
1126 	.read_avail = ad7192_read_avail,
1127 	.attrs = &ad7195_attribute_group,
1128 	.validate_trigger = ad_sd_validate_trigger,
1129 	.update_scan_mode = ad7192_update_scan_mode,
1130 };
1131 
1132 #define __AD719x_CHANNEL(_si, _channel1, _channel2, _address, _type, \
1133 	_mask_all, _mask_type_av, _mask_all_av, _ext_info) \
1134 	{ \
1135 		.type = (_type), \
1136 		.differential = ((_channel2) == -1 ? 0 : 1), \
1137 		.indexed = 1, \
1138 		.channel = (_channel1), \
1139 		.channel2 = (_channel2), \
1140 		.address = (_address), \
1141 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1142 			BIT(IIO_CHAN_INFO_OFFSET), \
1143 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
1144 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
1145 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1146 			(_mask_all), \
1147 		.info_mask_shared_by_type_available = (_mask_type_av), \
1148 		.info_mask_shared_by_all_available = \
1149 			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) | \
1150 			(_mask_all_av), \
1151 		.ext_info = (_ext_info), \
1152 		.scan_index = (_si), \
1153 		.scan_type = { \
1154 			.sign = 'u', \
1155 			.realbits = 24, \
1156 			.storagebits = 32, \
1157 			.endianness = IIO_BE, \
1158 		}, \
1159 	}
1160 
1161 #define AD719x_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1162 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, IIO_VOLTAGE, 0, \
1163 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1164 
1165 #define AD719x_CHANNEL(_si, _channel1, _address) \
1166 	__AD719x_CHANNEL(_si, _channel1, -1, _address, IIO_VOLTAGE, 0, \
1167 		BIT(IIO_CHAN_INFO_SCALE), 0, ad7192_calibsys_ext_info)
1168 
1169 #define AD719x_TEMP_CHANNEL(_si, _address) \
1170 	__AD719x_CHANNEL(_si, 0, -1, _address, IIO_TEMP, 0, 0, 0, NULL)
1171 
1172 #define AD7193_DIFF_CHANNEL(_si, _channel1, _channel2, _address) \
1173 	__AD719x_CHANNEL(_si, _channel1, _channel2, _address, \
1174 		IIO_VOLTAGE, \
1175 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1176 		BIT(IIO_CHAN_INFO_SCALE), \
1177 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
1178 		ad7192_calibsys_ext_info)
1179 
1180 #define AD7193_CHANNEL(_si, _channel1, _address) \
1181 	AD7193_DIFF_CHANNEL(_si, _channel1, -1, _address)
1182 
1183 static const struct iio_chan_spec ad7192_channels[] = {
1184 	AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M),
1185 	AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M),
1186 	AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP),
1187 	AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M),
1188 	AD719x_CHANNEL(4, 1, AD7192_CH_AIN1),
1189 	AD719x_CHANNEL(5, 2, AD7192_CH_AIN2),
1190 	AD719x_CHANNEL(6, 3, AD7192_CH_AIN3),
1191 	AD719x_CHANNEL(7, 4, AD7192_CH_AIN4),
1192 	IIO_CHAN_SOFT_TIMESTAMP(8),
1193 };
1194 
1195 static const struct iio_chan_spec ad7193_channels[] = {
1196 	AD7193_DIFF_CHANNEL(0, 1, 2, AD7193_CH_AIN1P_AIN2M),
1197 	AD7193_DIFF_CHANNEL(1, 3, 4, AD7193_CH_AIN3P_AIN4M),
1198 	AD7193_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M),
1199 	AD7193_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M),
1200 	AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP),
1201 	AD7193_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M),
1202 	AD7193_CHANNEL(6, 1, AD7193_CH_AIN1),
1203 	AD7193_CHANNEL(7, 2, AD7193_CH_AIN2),
1204 	AD7193_CHANNEL(8, 3, AD7193_CH_AIN3),
1205 	AD7193_CHANNEL(9, 4, AD7193_CH_AIN4),
1206 	AD7193_CHANNEL(10, 5, AD7193_CH_AIN5),
1207 	AD7193_CHANNEL(11, 6, AD7193_CH_AIN6),
1208 	AD7193_CHANNEL(12, 7, AD7193_CH_AIN7),
1209 	AD7193_CHANNEL(13, 8, AD7193_CH_AIN8),
1210 	IIO_CHAN_SOFT_TIMESTAMP(14),
1211 };
1212 
ad7194_validate_ain_channel(struct device * dev,u32 ain)1213 static bool ad7194_validate_ain_channel(struct device *dev, u32 ain)
1214 {
1215 	return in_range(ain, AD7194_CH_AIN_START, AD7194_CH_AIN_NR);
1216 }
1217 
ad7194_parse_channels(struct iio_dev * indio_dev)1218 static int ad7194_parse_channels(struct iio_dev *indio_dev)
1219 {
1220 	struct device *dev = indio_dev->dev.parent;
1221 	struct iio_chan_spec *ad7194_channels;
1222 	const struct iio_chan_spec ad7194_chan = AD7193_CHANNEL(0, 0, 0);
1223 	const struct iio_chan_spec ad7194_chan_diff = AD7193_DIFF_CHANNEL(0, 0, 0, 0);
1224 	const struct iio_chan_spec ad7194_chan_temp = AD719x_TEMP_CHANNEL(0, 0);
1225 	const struct iio_chan_spec ad7194_chan_timestamp = IIO_CHAN_SOFT_TIMESTAMP(0);
1226 	unsigned int num_channels, index = 0;
1227 	u32 ain[2];
1228 	int ret;
1229 
1230 	num_channels = device_get_child_node_count(dev);
1231 	if (num_channels > AD7194_CH_MAX_NR)
1232 		return dev_err_probe(dev, -EINVAL, "Too many channels: %u\n",
1233 				     num_channels);
1234 
1235 	num_channels += AD7194_CH_BASE_NR;
1236 
1237 	ad7194_channels = devm_kcalloc(dev, num_channels,
1238 				       sizeof(*ad7194_channels), GFP_KERNEL);
1239 	if (!ad7194_channels)
1240 		return -ENOMEM;
1241 
1242 	indio_dev->channels = ad7194_channels;
1243 	indio_dev->num_channels = num_channels;
1244 
1245 	device_for_each_child_node_scoped(dev, child) {
1246 		ret = fwnode_property_read_u32_array(child, "diff-channels",
1247 						     ain, ARRAY_SIZE(ain));
1248 		if (ret == 0) {
1249 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1250 				return dev_err_probe(dev, -EINVAL,
1251 						     "Invalid AIN channel: %u\n",
1252 						     ain[0]);
1253 
1254 			if (!ad7194_validate_ain_channel(dev, ain[1]))
1255 				return dev_err_probe(dev, -EINVAL,
1256 						     "Invalid AIN channel: %u\n",
1257 						     ain[1]);
1258 
1259 			*ad7194_channels = ad7194_chan_diff;
1260 			ad7194_channels->scan_index = index++;
1261 			ad7194_channels->channel = ain[0];
1262 			ad7194_channels->channel2 = ain[1];
1263 			ad7194_channels->address = AD7194_DIFF_CH(ain[0], ain[1]);
1264 		} else {
1265 			ret = fwnode_property_read_u32(child, "single-channel",
1266 						       &ain[0]);
1267 			if (ret)
1268 				return dev_err_probe(dev, ret,
1269 						     "Missing channel property\n");
1270 
1271 			if (!ad7194_validate_ain_channel(dev, ain[0]))
1272 				return dev_err_probe(dev, -EINVAL,
1273 						     "Invalid AIN channel: %u\n",
1274 						     ain[0]);
1275 
1276 			*ad7194_channels = ad7194_chan;
1277 			ad7194_channels->scan_index = index++;
1278 			ad7194_channels->channel = ain[0];
1279 			ad7194_channels->address = AD7194_CH(ain[0]);
1280 		}
1281 		ad7194_channels++;
1282 	}
1283 
1284 	*ad7194_channels = ad7194_chan_temp;
1285 	ad7194_channels->scan_index = index++;
1286 	ad7194_channels->address = AD7194_CH_TEMP;
1287 	ad7194_channels++;
1288 
1289 	*ad7194_channels = ad7194_chan_timestamp;
1290 	ad7194_channels->scan_index = index;
1291 
1292 	return 0;
1293 }
1294 
1295 static const struct ad7192_chip_info ad7192_chip_info_tbl[] = {
1296 	[ID_AD7190] = {
1297 		.chip_id = CHIPID_AD7190,
1298 		.name = "ad7190",
1299 		.channels = ad7192_channels,
1300 		.num_channels = ARRAY_SIZE(ad7192_channels),
1301 		.sigma_delta_info = &ad7192_sigma_delta_info,
1302 		.info = &ad7192_info,
1303 	},
1304 	[ID_AD7192] = {
1305 		.chip_id = CHIPID_AD7192,
1306 		.name = "ad7192",
1307 		.channels = ad7192_channels,
1308 		.num_channels = ARRAY_SIZE(ad7192_channels),
1309 		.sigma_delta_info = &ad7192_sigma_delta_info,
1310 		.info = &ad7192_info,
1311 	},
1312 	[ID_AD7193] = {
1313 		.chip_id = CHIPID_AD7193,
1314 		.name = "ad7193",
1315 		.channels = ad7193_channels,
1316 		.num_channels = ARRAY_SIZE(ad7193_channels),
1317 		.sigma_delta_info = &ad7192_sigma_delta_info,
1318 		.info = &ad7192_info,
1319 	},
1320 	[ID_AD7194] = {
1321 		.chip_id = CHIPID_AD7194,
1322 		.name = "ad7194",
1323 		.info = &ad7194_info,
1324 		.sigma_delta_info = &ad7194_sigma_delta_info,
1325 		.parse_channels = ad7194_parse_channels,
1326 	},
1327 	[ID_AD7195] = {
1328 		.chip_id = CHIPID_AD7195,
1329 		.name = "ad7195",
1330 		.channels = ad7192_channels,
1331 		.num_channels = ARRAY_SIZE(ad7192_channels),
1332 		.sigma_delta_info = &ad7192_sigma_delta_info,
1333 		.info = &ad7195_info,
1334 	},
1335 };
1336 
ad7192_probe(struct spi_device * spi)1337 static int ad7192_probe(struct spi_device *spi)
1338 {
1339 	struct device *dev = &spi->dev;
1340 	struct ad7192_state *st;
1341 	struct iio_dev *indio_dev;
1342 	int ret, avdd_mv;
1343 
1344 	if (!spi->irq)
1345 		return dev_err_probe(dev, -ENODEV, "Failed to get IRQ\n");
1346 
1347 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1348 	if (!indio_dev)
1349 		return -ENOMEM;
1350 
1351 	st = iio_priv(indio_dev);
1352 
1353 	mutex_init(&st->lock);
1354 
1355 	/*
1356 	 * Regulator aincom is optional to maintain compatibility with older DT.
1357 	 * Newer firmware should provide a zero volt fixed supply if wired to
1358 	 * ground.
1359 	 */
1360 	ret = devm_regulator_get_enable_read_voltage(dev, "aincom");
1361 	if (ret < 0 && ret != -ENODEV)
1362 		return dev_err_probe(dev, ret, "Failed to get AINCOM voltage\n");
1363 
1364 	st->aincom_mv = ret == -ENODEV ? 0 : ret / MILLI;
1365 
1366 	/* AVDD can optionally be used as reference voltage */
1367 	ret = devm_regulator_get_enable_read_voltage(dev, "avdd");
1368 	if (ret == -ENODEV || ret == -EINVAL) {
1369 		int ret2;
1370 
1371 		/*
1372 		 * We get -EINVAL if avdd is a supply with unknown voltage. We
1373 		 * still need to enable it since it is also a power supply.
1374 		 */
1375 		ret2 = devm_regulator_get_enable(dev, "avdd");
1376 		if (ret2)
1377 			return dev_err_probe(dev, ret2,
1378 					     "Failed to enable AVDD supply\n");
1379 	} else if (ret < 0) {
1380 		return dev_err_probe(dev, ret, "Failed to get AVDD voltage\n");
1381 	}
1382 
1383 	avdd_mv = ret == -ENODEV || ret == -EINVAL ? 0 : ret / MILLI;
1384 
1385 	ret = devm_regulator_get_enable(dev, "dvdd");
1386 	if (ret)
1387 		return dev_err_probe(dev, ret, "Failed to enable specified DVdd supply\n");
1388 
1389 	/*
1390 	 * This is either REFIN1 or REFIN2 depending on adi,refin2-pins-enable.
1391 	 * If this supply is not present, fall back to AVDD as reference.
1392 	 */
1393 	ret = devm_regulator_get_enable_read_voltage(dev, "vref");
1394 	if (ret == -ENODEV) {
1395 		if (avdd_mv == 0)
1396 			return dev_err_probe(dev, -ENODEV,
1397 					     "No reference voltage available\n");
1398 	} else if (ret < 0) {
1399 		return ret;
1400 	}
1401 
1402 	st->int_vref_mv = ret == -ENODEV ? avdd_mv : ret / MILLI;
1403 
1404 	st->chip_info = spi_get_device_match_data(spi);
1405 	if (!st->chip_info)
1406 		return -ENODEV;
1407 
1408 	indio_dev->name = st->chip_info->name;
1409 	indio_dev->modes = INDIO_DIRECT_MODE;
1410 	indio_dev->info = st->chip_info->info;
1411 	if (st->chip_info->parse_channels) {
1412 		ret = st->chip_info->parse_channels(indio_dev);
1413 		if (ret)
1414 			return ret;
1415 	} else {
1416 		indio_dev->channels = st->chip_info->channels;
1417 		indio_dev->num_channels = st->chip_info->num_channels;
1418 	}
1419 
1420 	ret = ad_sd_init(&st->sd, indio_dev, spi, st->chip_info->sigma_delta_info);
1421 	if (ret)
1422 		return ret;
1423 
1424 	ret = devm_ad_sd_setup_buffer_and_trigger(dev, indio_dev);
1425 	if (ret)
1426 		return ret;
1427 
1428 	ret = ad7192_clock_setup(st);
1429 	if (ret)
1430 		return ret;
1431 
1432 	ret = ad7192_setup(indio_dev, dev);
1433 	if (ret)
1434 		return ret;
1435 
1436 	return devm_iio_device_register(dev, indio_dev);
1437 }
1438 
1439 static const struct of_device_id ad7192_of_match[] = {
1440 	{ .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] },
1441 	{ .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] },
1442 	{ .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] },
1443 	{ .compatible = "adi,ad7194", .data = &ad7192_chip_info_tbl[ID_AD7194] },
1444 	{ .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] },
1445 	{ }
1446 };
1447 MODULE_DEVICE_TABLE(of, ad7192_of_match);
1448 
1449 static const struct spi_device_id ad7192_ids[] = {
1450 	{ "ad7190", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7190] },
1451 	{ "ad7192", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7192] },
1452 	{ "ad7193", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7193] },
1453 	{ "ad7194", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7194] },
1454 	{ "ad7195", (kernel_ulong_t)&ad7192_chip_info_tbl[ID_AD7195] },
1455 	{ }
1456 };
1457 MODULE_DEVICE_TABLE(spi, ad7192_ids);
1458 
1459 static struct spi_driver ad7192_driver = {
1460 	.driver = {
1461 		.name	= "ad7192",
1462 		.of_match_table = ad7192_of_match,
1463 	},
1464 	.probe		= ad7192_probe,
1465 	.id_table	= ad7192_ids,
1466 };
1467 module_spi_driver(ad7192_driver);
1468 
1469 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1470 MODULE_DESCRIPTION("Analog Devices AD7192 and similar ADC");
1471 MODULE_LICENSE("GPL v2");
1472 MODULE_IMPORT_NS("IIO_AD_SIGMA_DELTA");
1473