1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * INA3221 Triple Current/Voltage Monitor
4 *
5 * Copyright (C) 2016 Texas Instruments Incorporated - https://www.ti.com/
6 *	Andrew F. Davis <afd@ti.com>
7 */
8
9#include <linux/debugfs.h>
10#include <linux/hwmon.h>
11#include <linux/hwmon-sysfs.h>
12#include <linux/i2c.h>
13#include <linux/module.h>
14#include <linux/mutex.h>
15#include <linux/of.h>
16#include <linux/pm_runtime.h>
17#include <linux/regmap.h>
18#include <linux/util_macros.h>
19
20#define INA3221_DRIVER_NAME		"ina3221"
21
22#define INA3221_CONFIG			0x00
23#define INA3221_SHUNT1			0x01
24#define INA3221_BUS1			0x02
25#define INA3221_SHUNT2			0x03
26#define INA3221_BUS2			0x04
27#define INA3221_SHUNT3			0x05
28#define INA3221_BUS3			0x06
29#define INA3221_CRIT1			0x07
30#define INA3221_WARN1			0x08
31#define INA3221_CRIT2			0x09
32#define INA3221_WARN2			0x0a
33#define INA3221_CRIT3			0x0b
34#define INA3221_WARN3			0x0c
35#define INA3221_SHUNT_SUM		0x0d
36#define INA3221_CRIT_SUM		0x0e
37#define INA3221_MASK_ENABLE		0x0f
38
39#define INA3221_CONFIG_MODE_MASK	GENMASK(2, 0)
40#define INA3221_CONFIG_MODE_POWERDOWN	0
41#define INA3221_CONFIG_MODE_SHUNT	BIT(0)
42#define INA3221_CONFIG_MODE_BUS		BIT(1)
43#define INA3221_CONFIG_MODE_CONTINUOUS	BIT(2)
44#define INA3221_CONFIG_VSH_CT_SHIFT	3
45#define INA3221_CONFIG_VSH_CT_MASK	GENMASK(5, 3)
46#define INA3221_CONFIG_VSH_CT(x)	(((x) & GENMASK(5, 3)) >> 3)
47#define INA3221_CONFIG_VBUS_CT_SHIFT	6
48#define INA3221_CONFIG_VBUS_CT_MASK	GENMASK(8, 6)
49#define INA3221_CONFIG_VBUS_CT(x)	(((x) & GENMASK(8, 6)) >> 6)
50#define INA3221_CONFIG_AVG_SHIFT	9
51#define INA3221_CONFIG_AVG_MASK		GENMASK(11, 9)
52#define INA3221_CONFIG_AVG(x)		(((x) & GENMASK(11, 9)) >> 9)
53#define INA3221_CONFIG_CHs_EN_MASK	GENMASK(14, 12)
54#define INA3221_CONFIG_CHx_EN(x)	BIT(14 - (x))
55
56#define INA3221_MASK_ENABLE_SCC_MASK	GENMASK(14, 12)
57
58#define INA3221_CONFIG_DEFAULT		0x7127
59#define INA3221_RSHUNT_DEFAULT		10000
60
61enum ina3221_fields {
62	/* Configuration */
63	F_RST,
64
65	/* Status Flags */
66	F_CVRF,
67
68	/* Warning Flags */
69	F_WF3, F_WF2, F_WF1,
70
71	/* Alert Flags: SF is the summation-alert flag */
72	F_SF, F_CF3, F_CF2, F_CF1,
73
74	/* sentinel */
75	F_MAX_FIELDS
76};
77
78static const struct reg_field ina3221_reg_fields[] = {
79	[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
80
81	[F_CVRF] = REG_FIELD(INA3221_MASK_ENABLE, 0, 0),
82	[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
83	[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
84	[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
85	[F_SF] = REG_FIELD(INA3221_MASK_ENABLE, 6, 6),
86	[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
87	[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
88	[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
89};
90
91enum ina3221_channels {
92	INA3221_CHANNEL1,
93	INA3221_CHANNEL2,
94	INA3221_CHANNEL3,
95	INA3221_NUM_CHANNELS
96};
97
98/**
99 * struct ina3221_input - channel input source specific information
100 * @label: label of channel input source
101 * @shunt_resistor: shunt resistor value of channel input source
102 * @disconnected: connection status of channel input source
103 * @summation_disable: channel summation status of input source
104 */
105struct ina3221_input {
106	const char *label;
107	int shunt_resistor;
108	bool disconnected;
109	bool summation_disable;
110};
111
112/**
113 * struct ina3221_data - device specific information
114 * @pm_dev: Device pointer for pm runtime
115 * @regmap: Register map of the device
116 * @fields: Register fields of the device
117 * @inputs: Array of channel input source specific structures
118 * @lock: mutex lock to serialize sysfs attribute accesses
119 * @debugfs: Pointer to debugfs entry for device
120 * @reg_config: Register value of INA3221_CONFIG
121 * @summation_shunt_resistor: equivalent shunt resistor value for summation
122 * @summation_channel_control: Value written to SCC field in INA3221_MASK_ENABLE
123 * @single_shot: running in single-shot operating mode
124 */
125struct ina3221_data {
126	struct device *pm_dev;
127	struct regmap *regmap;
128	struct regmap_field *fields[F_MAX_FIELDS];
129	struct ina3221_input inputs[INA3221_NUM_CHANNELS];
130	struct mutex lock;
131	struct dentry *debugfs;
132	u32 reg_config;
133	int summation_shunt_resistor;
134	u32 summation_channel_control;
135
136	bool single_shot;
137};
138
139static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
140{
141	/* Summation channel checks shunt resistor values */
142	if (channel > INA3221_CHANNEL3)
143		return ina->summation_shunt_resistor != 0;
144
145	return pm_runtime_active(ina->pm_dev) &&
146	       (ina->reg_config & INA3221_CONFIG_CHx_EN(channel));
147}
148
149/*
150 * Helper function to return the resistor value for current summation.
151 *
152 * There is a condition to calculate current summation -- all the shunt
153 * resistor values should be the same, so as to simply fit the formula:
154 *     current summation = shunt voltage summation / shunt resistor
155 *
156 * Returns the equivalent shunt resistor value on success or 0 on failure
157 */
158static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina)
159{
160	struct ina3221_input *input = ina->inputs;
161	int i, shunt_resistor = 0;
162
163	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
164		if (input[i].disconnected || !input[i].shunt_resistor ||
165		    input[i].summation_disable)
166			continue;
167		if (!shunt_resistor) {
168			/* Found the reference shunt resistor value */
169			shunt_resistor = input[i].shunt_resistor;
170		} else {
171			/* No summation if resistor values are different */
172			if (shunt_resistor != input[i].shunt_resistor)
173				return 0;
174		}
175	}
176
177	return shunt_resistor;
178}
179
180/* Lookup table for Bus and Shunt conversion times in usec */
181static const u16 ina3221_conv_time[] = {
182	140, 204, 332, 588, 1100, 2116, 4156, 8244,
183};
184
185/* Lookup table for number of samples using in averaging mode */
186static const int ina3221_avg_samples[] = {
187	1, 4, 16, 64, 128, 256, 512, 1024,
188};
189
190/* Converting update_interval in msec to conversion time in usec */
191static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval)
192{
193	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
194	u32 samples_idx = INA3221_CONFIG_AVG(config);
195	u32 samples = ina3221_avg_samples[samples_idx];
196
197	/* Bisect the result to Bus and Shunt conversion times */
198	return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples);
199}
200
201/* Converting CONFIG register value to update_interval in usec */
202static inline u32 ina3221_reg_to_interval_us(u16 config)
203{
204	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
205	u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config);
206	u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config);
207	u32 vbus_ct = ina3221_conv_time[vbus_ct_idx];
208	u32 vsh_ct = ina3221_conv_time[vsh_ct_idx];
209
210	/* Calculate total conversion time */
211	return channels * (vbus_ct + vsh_ct);
212}
213
214static inline int ina3221_wait_for_data(struct ina3221_data *ina)
215{
216	u32 wait, cvrf;
217
218	wait = ina3221_reg_to_interval_us(ina->reg_config);
219
220	/* Polling the CVRF bit to make sure read data is ready */
221	return regmap_field_read_poll_timeout(ina->fields[F_CVRF],
222					      cvrf, cvrf, wait, wait * 2);
223}
224
225static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
226			      int *val)
227{
228	unsigned int regval;
229	int ret;
230
231	ret = regmap_read(ina->regmap, reg, &regval);
232	if (ret)
233		return ret;
234
235	/*
236	 * Shunt Voltage Sum register has 14-bit value with 1-bit shift
237	 * Other Shunt Voltage registers have 12 bits with 3-bit shift
238	 */
239	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
240		*val = sign_extend32(regval >> 1, 14);
241	else
242		*val = sign_extend32(regval >> 3, 12);
243
244	return 0;
245}
246
247static const u8 ina3221_in_reg[] = {
248	INA3221_BUS1,
249	INA3221_BUS2,
250	INA3221_BUS3,
251	INA3221_SHUNT1,
252	INA3221_SHUNT2,
253	INA3221_SHUNT3,
254	INA3221_SHUNT_SUM,
255};
256
257static int ina3221_read_chip(struct device *dev, u32 attr, long *val)
258{
259	struct ina3221_data *ina = dev_get_drvdata(dev);
260	int regval;
261
262	switch (attr) {
263	case hwmon_chip_samples:
264		regval = INA3221_CONFIG_AVG(ina->reg_config);
265		*val = ina3221_avg_samples[regval];
266		return 0;
267	case hwmon_chip_update_interval:
268		/* Return in msec */
269		*val = ina3221_reg_to_interval_us(ina->reg_config);
270		*val = DIV_ROUND_CLOSEST(*val, 1000);
271		return 0;
272	default:
273		return -EOPNOTSUPP;
274	}
275}
276
277static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
278{
279	const bool is_shunt = channel > INA3221_CHANNEL3;
280	struct ina3221_data *ina = dev_get_drvdata(dev);
281	u8 reg = ina3221_in_reg[channel];
282	int regval, ret;
283
284	/*
285	 * Translate shunt channel index to sensor channel index except
286	 * the 7th channel (6 since being 0-aligned) is for summation.
287	 */
288	if (channel != 6)
289		channel %= INA3221_NUM_CHANNELS;
290
291	switch (attr) {
292	case hwmon_in_input:
293		if (!ina3221_is_enabled(ina, channel))
294			return -ENODATA;
295
296		/* Write CONFIG register to trigger a single-shot measurement */
297		if (ina->single_shot) {
298			regmap_write(ina->regmap, INA3221_CONFIG,
299				     ina->reg_config);
300
301			ret = ina3221_wait_for_data(ina);
302			if (ret)
303				return ret;
304		}
305
306		ret = ina3221_read_value(ina, reg, &regval);
307		if (ret)
308			return ret;
309
310		/*
311		 * Scale of shunt voltage (uV): LSB is 40uV
312		 * Scale of bus voltage (mV): LSB is 8mV
313		 */
314		*val = regval * (is_shunt ? 40 : 8);
315		return 0;
316	case hwmon_in_enable:
317		*val = ina3221_is_enabled(ina, channel);
318		return 0;
319	default:
320		return -EOPNOTSUPP;
321	}
322}
323
324static const u8 ina3221_curr_reg[][INA3221_NUM_CHANNELS + 1] = {
325	[hwmon_curr_input] = { INA3221_SHUNT1, INA3221_SHUNT2,
326			       INA3221_SHUNT3, INA3221_SHUNT_SUM },
327	[hwmon_curr_max] = { INA3221_WARN1, INA3221_WARN2, INA3221_WARN3, 0 },
328	[hwmon_curr_crit] = { INA3221_CRIT1, INA3221_CRIT2,
329			      INA3221_CRIT3, INA3221_CRIT_SUM },
330	[hwmon_curr_max_alarm] = { F_WF1, F_WF2, F_WF3, 0 },
331	[hwmon_curr_crit_alarm] = { F_CF1, F_CF2, F_CF3, F_SF },
332};
333
334static int ina3221_read_curr(struct device *dev, u32 attr,
335			     int channel, long *val)
336{
337	struct ina3221_data *ina = dev_get_drvdata(dev);
338	struct ina3221_input *input = ina->inputs;
339	u8 reg = ina3221_curr_reg[attr][channel];
340	int resistance_uo, voltage_nv;
341	int regval, ret;
342
343	if (channel > INA3221_CHANNEL3)
344		resistance_uo = ina->summation_shunt_resistor;
345	else
346		resistance_uo = input[channel].shunt_resistor;
347
348	switch (attr) {
349	case hwmon_curr_input:
350		if (!ina3221_is_enabled(ina, channel))
351			return -ENODATA;
352
353		/* Write CONFIG register to trigger a single-shot measurement */
354		if (ina->single_shot) {
355			regmap_write(ina->regmap, INA3221_CONFIG,
356				     ina->reg_config);
357
358			ret = ina3221_wait_for_data(ina);
359			if (ret)
360				return ret;
361		}
362
363		fallthrough;
364	case hwmon_curr_crit:
365	case hwmon_curr_max:
366		if (!resistance_uo)
367			return -ENODATA;
368
369		ret = ina3221_read_value(ina, reg, &regval);
370		if (ret)
371			return ret;
372
373		/* Scale of shunt voltage: LSB is 40uV (40000nV) */
374		voltage_nv = regval * 40000;
375		/* Return current in mA */
376		*val = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
377		return 0;
378	case hwmon_curr_crit_alarm:
379	case hwmon_curr_max_alarm:
380		/* No actual register read if channel is disabled */
381		if (!ina3221_is_enabled(ina, channel)) {
382			/* Return 0 for alert flags */
383			*val = 0;
384			return 0;
385		}
386		ret = regmap_field_read(ina->fields[reg], &regval);
387		if (ret)
388			return ret;
389		*val = regval;
390		return 0;
391	default:
392		return -EOPNOTSUPP;
393	}
394}
395
396static int ina3221_write_chip(struct device *dev, u32 attr, long val)
397{
398	struct ina3221_data *ina = dev_get_drvdata(dev);
399	int ret, idx;
400	u32 tmp;
401
402	switch (attr) {
403	case hwmon_chip_samples:
404		idx = find_closest(val, ina3221_avg_samples,
405				   ARRAY_SIZE(ina3221_avg_samples));
406
407		tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) |
408		      (idx << INA3221_CONFIG_AVG_SHIFT);
409		ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
410		if (ret)
411			return ret;
412
413		/* Update reg_config accordingly */
414		ina->reg_config = tmp;
415		return 0;
416	case hwmon_chip_update_interval:
417		tmp = ina3221_interval_ms_to_conv_time(ina->reg_config, val);
418		idx = find_closest(tmp, ina3221_conv_time,
419				   ARRAY_SIZE(ina3221_conv_time));
420
421		/* Update Bus and Shunt voltage conversion times */
422		tmp = INA3221_CONFIG_VBUS_CT_MASK | INA3221_CONFIG_VSH_CT_MASK;
423		tmp = (ina->reg_config & ~tmp) |
424		      (idx << INA3221_CONFIG_VBUS_CT_SHIFT) |
425		      (idx << INA3221_CONFIG_VSH_CT_SHIFT);
426		ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
427		if (ret)
428			return ret;
429
430		/* Update reg_config accordingly */
431		ina->reg_config = tmp;
432		return 0;
433	default:
434		return -EOPNOTSUPP;
435	}
436}
437
438static int ina3221_write_curr(struct device *dev, u32 attr,
439			      int channel, long val)
440{
441	struct ina3221_data *ina = dev_get_drvdata(dev);
442	struct ina3221_input *input = ina->inputs;
443	u8 reg = ina3221_curr_reg[attr][channel];
444	int resistance_uo, current_ma, voltage_uv;
445	int regval;
446
447	if (channel > INA3221_CHANNEL3)
448		resistance_uo = ina->summation_shunt_resistor;
449	else
450		resistance_uo = input[channel].shunt_resistor;
451
452	if (!resistance_uo)
453		return -EOPNOTSUPP;
454
455	/* clamp current */
456	current_ma = clamp_val(val,
457			       INT_MIN / resistance_uo,
458			       INT_MAX / resistance_uo);
459
460	voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
461
462	/* clamp voltage */
463	voltage_uv = clamp_val(voltage_uv, -163800, 163800);
464
465	/*
466	 * Formula to convert voltage_uv to register value:
467	 *     regval = (voltage_uv / scale) << shift
468	 * Note:
469	 *     The scale is 40uV for all shunt voltage registers
470	 *     Shunt Voltage Sum register left-shifts 1 bit
471	 *     All other Shunt Voltage registers shift 3 bits
472	 * Results:
473	 *     SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV
474	 *     SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV
475	 */
476	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
477		regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe;
478	else
479		regval = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
480
481	return regmap_write(ina->regmap, reg, regval);
482}
483
484static int ina3221_write_enable(struct device *dev, int channel, bool enable)
485{
486	struct ina3221_data *ina = dev_get_drvdata(dev);
487	u16 config, mask = INA3221_CONFIG_CHx_EN(channel);
488	u16 config_old = ina->reg_config & mask;
489	u32 tmp;
490	int ret;
491
492	config = enable ? mask : 0;
493
494	/* Bypass if enable status is not being changed */
495	if (config_old == config)
496		return 0;
497
498	/* For enabling routine, increase refcount and resume() at first */
499	if (enable) {
500		ret = pm_runtime_resume_and_get(ina->pm_dev);
501		if (ret < 0) {
502			dev_err(dev, "Failed to get PM runtime\n");
503			return ret;
504		}
505	}
506
507	/* Enable or disable the channel */
508	tmp = (ina->reg_config & ~mask) | (config & mask);
509	ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
510	if (ret)
511		goto fail;
512
513	/* Cache the latest config register value */
514	ina->reg_config = tmp;
515
516	/* For disabling routine, decrease refcount or suspend() at last */
517	if (!enable)
518		pm_runtime_put_sync(ina->pm_dev);
519
520	return 0;
521
522fail:
523	if (enable) {
524		dev_err(dev, "Failed to enable channel %d: error %d\n",
525			channel, ret);
526		pm_runtime_put_sync(ina->pm_dev);
527	}
528
529	return ret;
530}
531
532static int ina3221_read(struct device *dev, enum hwmon_sensor_types type,
533			u32 attr, int channel, long *val)
534{
535	struct ina3221_data *ina = dev_get_drvdata(dev);
536	int ret;
537
538	mutex_lock(&ina->lock);
539
540	switch (type) {
541	case hwmon_chip:
542		ret = ina3221_read_chip(dev, attr, val);
543		break;
544	case hwmon_in:
545		/* 0-align channel ID */
546		ret = ina3221_read_in(dev, attr, channel - 1, val);
547		break;
548	case hwmon_curr:
549		ret = ina3221_read_curr(dev, attr, channel, val);
550		break;
551	default:
552		ret = -EOPNOTSUPP;
553		break;
554	}
555
556	mutex_unlock(&ina->lock);
557
558	return ret;
559}
560
561static int ina3221_write(struct device *dev, enum hwmon_sensor_types type,
562			 u32 attr, int channel, long val)
563{
564	struct ina3221_data *ina = dev_get_drvdata(dev);
565	int ret;
566
567	mutex_lock(&ina->lock);
568
569	switch (type) {
570	case hwmon_chip:
571		ret = ina3221_write_chip(dev, attr, val);
572		break;
573	case hwmon_in:
574		/* 0-align channel ID */
575		ret = ina3221_write_enable(dev, channel - 1, val);
576		break;
577	case hwmon_curr:
578		ret = ina3221_write_curr(dev, attr, channel, val);
579		break;
580	default:
581		ret = -EOPNOTSUPP;
582		break;
583	}
584
585	mutex_unlock(&ina->lock);
586
587	return ret;
588}
589
590static int ina3221_read_string(struct device *dev, enum hwmon_sensor_types type,
591			       u32 attr, int channel, const char **str)
592{
593	struct ina3221_data *ina = dev_get_drvdata(dev);
594	int index = channel - 1;
595
596	if (channel == 7)
597		*str = "sum of shunt voltages";
598	else
599		*str = ina->inputs[index].label;
600
601	return 0;
602}
603
604static umode_t ina3221_is_visible(const void *drvdata,
605				  enum hwmon_sensor_types type,
606				  u32 attr, int channel)
607{
608	const struct ina3221_data *ina = drvdata;
609	const struct ina3221_input *input = NULL;
610
611	switch (type) {
612	case hwmon_chip:
613		switch (attr) {
614		case hwmon_chip_samples:
615		case hwmon_chip_update_interval:
616			return 0644;
617		default:
618			return 0;
619		}
620	case hwmon_in:
621		/* Ignore in0_ */
622		if (channel == 0)
623			return 0;
624
625		switch (attr) {
626		case hwmon_in_label:
627			if (channel - 1 <= INA3221_CHANNEL3)
628				input = &ina->inputs[channel - 1];
629			else if (channel == 7)
630				return 0444;
631			/* Hide label node if label is not provided */
632			return (input && input->label) ? 0444 : 0;
633		case hwmon_in_input:
634			return 0444;
635		case hwmon_in_enable:
636			return 0644;
637		default:
638			return 0;
639		}
640	case hwmon_curr:
641		switch (attr) {
642		case hwmon_curr_input:
643		case hwmon_curr_crit_alarm:
644		case hwmon_curr_max_alarm:
645			return 0444;
646		case hwmon_curr_crit:
647		case hwmon_curr_max:
648			return 0644;
649		default:
650			return 0;
651		}
652	default:
653		return 0;
654	}
655}
656
657#define INA3221_HWMON_CURR_CONFIG (HWMON_C_INPUT | \
658				   HWMON_C_CRIT | HWMON_C_CRIT_ALARM | \
659				   HWMON_C_MAX | HWMON_C_MAX_ALARM)
660
661static const struct hwmon_channel_info * const ina3221_info[] = {
662	HWMON_CHANNEL_INFO(chip,
663			   HWMON_C_SAMPLES,
664			   HWMON_C_UPDATE_INTERVAL),
665	HWMON_CHANNEL_INFO(in,
666			   /* 0: dummy, skipped in is_visible */
667			   HWMON_I_INPUT,
668			   /* 1-3: input voltage Channels */
669			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
670			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
671			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
672			   /* 4-6: shunt voltage Channels */
673			   HWMON_I_INPUT,
674			   HWMON_I_INPUT,
675			   HWMON_I_INPUT,
676			   /* 7: summation of shunt voltage channels */
677			   HWMON_I_INPUT | HWMON_I_LABEL),
678	HWMON_CHANNEL_INFO(curr,
679			   /* 1-3: current channels*/
680			   INA3221_HWMON_CURR_CONFIG,
681			   INA3221_HWMON_CURR_CONFIG,
682			   INA3221_HWMON_CURR_CONFIG,
683			   /* 4: summation of current channels */
684			   HWMON_C_INPUT | HWMON_C_CRIT | HWMON_C_CRIT_ALARM),
685	NULL
686};
687
688static const struct hwmon_ops ina3221_hwmon_ops = {
689	.is_visible = ina3221_is_visible,
690	.read_string = ina3221_read_string,
691	.read = ina3221_read,
692	.write = ina3221_write,
693};
694
695static const struct hwmon_chip_info ina3221_chip_info = {
696	.ops = &ina3221_hwmon_ops,
697	.info = ina3221_info,
698};
699
700/* Extra attribute groups */
701static ssize_t ina3221_shunt_show(struct device *dev,
702				  struct device_attribute *attr, char *buf)
703{
704	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
705	struct ina3221_data *ina = dev_get_drvdata(dev);
706	unsigned int channel = sd_attr->index;
707	struct ina3221_input *input = &ina->inputs[channel];
708
709	return sysfs_emit(buf, "%d\n", input->shunt_resistor);
710}
711
712static ssize_t ina3221_shunt_store(struct device *dev,
713				   struct device_attribute *attr,
714				   const char *buf, size_t count)
715{
716	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
717	struct ina3221_data *ina = dev_get_drvdata(dev);
718	unsigned int channel = sd_attr->index;
719	struct ina3221_input *input = &ina->inputs[channel];
720	int val;
721	int ret;
722
723	ret = kstrtoint(buf, 0, &val);
724	if (ret)
725		return ret;
726
727	val = clamp_val(val, 1, INT_MAX);
728
729	input->shunt_resistor = val;
730
731	/* Update summation_shunt_resistor for summation channel */
732	ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
733
734	return count;
735}
736
737/* shunt resistance */
738static SENSOR_DEVICE_ATTR_RW(shunt1_resistor, ina3221_shunt, INA3221_CHANNEL1);
739static SENSOR_DEVICE_ATTR_RW(shunt2_resistor, ina3221_shunt, INA3221_CHANNEL2);
740static SENSOR_DEVICE_ATTR_RW(shunt3_resistor, ina3221_shunt, INA3221_CHANNEL3);
741
742static struct attribute *ina3221_attrs[] = {
743	&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
744	&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
745	&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
746	NULL,
747};
748ATTRIBUTE_GROUPS(ina3221);
749
750static const struct regmap_range ina3221_yes_ranges[] = {
751	regmap_reg_range(INA3221_CONFIG, INA3221_BUS3),
752	regmap_reg_range(INA3221_SHUNT_SUM, INA3221_SHUNT_SUM),
753	regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
754};
755
756static const struct regmap_access_table ina3221_volatile_table = {
757	.yes_ranges = ina3221_yes_ranges,
758	.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
759};
760
761static const struct regmap_config ina3221_regmap_config = {
762	.reg_bits = 8,
763	.val_bits = 16,
764
765	.cache_type = REGCACHE_MAPLE,
766	.volatile_table = &ina3221_volatile_table,
767};
768
769static int ina3221_probe_child_from_dt(struct device *dev,
770				       struct device_node *child,
771				       struct ina3221_data *ina)
772{
773	struct ina3221_input *input;
774	u32 val;
775	int ret;
776
777	ret = of_property_read_u32(child, "reg", &val);
778	if (ret) {
779		dev_err(dev, "missing reg property of %pOFn\n", child);
780		return ret;
781	} else if (val > INA3221_CHANNEL3) {
782		dev_err(dev, "invalid reg %d of %pOFn\n", val, child);
783		return -EINVAL;
784	}
785
786	input = &ina->inputs[val];
787
788	/* Log the disconnected channel input */
789	if (!of_device_is_available(child)) {
790		input->disconnected = true;
791		return 0;
792	}
793
794	/* Save the connected input label if available */
795	of_property_read_string(child, "label", &input->label);
796
797	/* summation channel control */
798	input->summation_disable = of_property_read_bool(child, "ti,summation-disable");
799
800	/* Overwrite default shunt resistor value optionally */
801	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) {
802		if (val < 1 || val > INT_MAX) {
803			dev_err(dev, "invalid shunt resistor value %u of %pOFn\n",
804				val, child);
805			return -EINVAL;
806		}
807		input->shunt_resistor = val;
808	}
809
810	return 0;
811}
812
813static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
814{
815	const struct device_node *np = dev->of_node;
816	struct device_node *child;
817	int ret;
818
819	/* Compatible with non-DT platforms */
820	if (!np)
821		return 0;
822
823	ina->single_shot = of_property_read_bool(np, "ti,single-shot");
824
825	for_each_child_of_node(np, child) {
826		ret = ina3221_probe_child_from_dt(dev, child, ina);
827		if (ret) {
828			of_node_put(child);
829			return ret;
830		}
831	}
832
833	return 0;
834}
835
836static int ina3221_probe(struct i2c_client *client)
837{
838	struct device *dev = &client->dev;
839	struct ina3221_data *ina;
840	struct device *hwmon_dev;
841	char name[32];
842	int i, ret;
843
844	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
845	if (!ina)
846		return -ENOMEM;
847
848	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
849	if (IS_ERR(ina->regmap)) {
850		dev_err(dev, "Unable to allocate register map\n");
851		return PTR_ERR(ina->regmap);
852	}
853
854	for (i = 0; i < F_MAX_FIELDS; i++) {
855		ina->fields[i] = devm_regmap_field_alloc(dev,
856							 ina->regmap,
857							 ina3221_reg_fields[i]);
858		if (IS_ERR(ina->fields[i])) {
859			dev_err(dev, "Unable to allocate regmap fields\n");
860			return PTR_ERR(ina->fields[i]);
861		}
862	}
863
864	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
865		ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT;
866
867	ret = ina3221_probe_from_dt(dev, ina);
868	if (ret) {
869		dev_err(dev, "Unable to probe from device tree\n");
870		return ret;
871	}
872
873	/* The driver will be reset, so use reset value */
874	ina->reg_config = INA3221_CONFIG_DEFAULT;
875
876	/* Clear continuous bit to use single-shot mode */
877	if (ina->single_shot)
878		ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
879
880	/* Disable channels if their inputs are disconnected */
881	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
882		if (ina->inputs[i].disconnected)
883			ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i);
884	}
885
886	/* Initialize summation_shunt_resistor for summation channel control */
887	ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
888	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
889		if (!ina->inputs[i].summation_disable)
890			ina->summation_channel_control |= BIT(14 - i);
891	}
892
893	ina->pm_dev = dev;
894	mutex_init(&ina->lock);
895	dev_set_drvdata(dev, ina);
896
897	/* Enable PM runtime -- status is suspended by default */
898	pm_runtime_enable(ina->pm_dev);
899
900	/* Initialize (resume) the device */
901	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
902		if (ina->inputs[i].disconnected)
903			continue;
904		/* Match the refcount with number of enabled channels */
905		ret = pm_runtime_get_sync(ina->pm_dev);
906		if (ret < 0)
907			goto fail;
908	}
909
910	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina,
911							 &ina3221_chip_info,
912							 ina3221_groups);
913	if (IS_ERR(hwmon_dev)) {
914		dev_err(dev, "Unable to register hwmon device\n");
915		ret = PTR_ERR(hwmon_dev);
916		goto fail;
917	}
918
919	scnprintf(name, sizeof(name), "%s-%s", INA3221_DRIVER_NAME, dev_name(dev));
920	ina->debugfs = debugfs_create_dir(name, NULL);
921
922	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
923		scnprintf(name, sizeof(name), "in%d_summation_disable", i);
924		debugfs_create_bool(name, 0400, ina->debugfs,
925				    &ina->inputs[i].summation_disable);
926	}
927
928	return 0;
929
930fail:
931	pm_runtime_disable(ina->pm_dev);
932	pm_runtime_set_suspended(ina->pm_dev);
933	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
934	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
935		pm_runtime_put_noidle(ina->pm_dev);
936	mutex_destroy(&ina->lock);
937
938	return ret;
939}
940
941static void ina3221_remove(struct i2c_client *client)
942{
943	struct ina3221_data *ina = dev_get_drvdata(&client->dev);
944	int i;
945
946	debugfs_remove_recursive(ina->debugfs);
947
948	pm_runtime_disable(ina->pm_dev);
949	pm_runtime_set_suspended(ina->pm_dev);
950
951	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
952	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
953		pm_runtime_put_noidle(ina->pm_dev);
954
955	mutex_destroy(&ina->lock);
956}
957
958static int ina3221_suspend(struct device *dev)
959{
960	struct ina3221_data *ina = dev_get_drvdata(dev);
961	int ret;
962
963	/* Save config register value and enable cache-only */
964	ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config);
965	if (ret)
966		return ret;
967
968	/* Set to power-down mode for power saving */
969	ret = regmap_update_bits(ina->regmap, INA3221_CONFIG,
970				 INA3221_CONFIG_MODE_MASK,
971				 INA3221_CONFIG_MODE_POWERDOWN);
972	if (ret)
973		return ret;
974
975	regcache_cache_only(ina->regmap, true);
976	regcache_mark_dirty(ina->regmap);
977
978	return 0;
979}
980
981static int ina3221_resume(struct device *dev)
982{
983	struct ina3221_data *ina = dev_get_drvdata(dev);
984	int ret;
985
986	regcache_cache_only(ina->regmap, false);
987
988	/* Software reset the chip */
989	ret = regmap_field_write(ina->fields[F_RST], true);
990	if (ret) {
991		dev_err(dev, "Unable to reset device\n");
992		return ret;
993	}
994
995	/* Restore cached register values to hardware */
996	ret = regcache_sync(ina->regmap);
997	if (ret)
998		return ret;
999
1000	/* Restore config register value to hardware */
1001	ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config);
1002	if (ret)
1003		return ret;
1004
1005	/* Initialize summation channel control */
1006	if (ina->summation_shunt_resistor) {
1007		/*
1008		 * Sum only channels that are not disabled for summation.
1009		 * Shunt measurements of disconnected channels should
1010		 * be 0, so it does not matter for summation.
1011		 */
1012		ret = regmap_update_bits(ina->regmap, INA3221_MASK_ENABLE,
1013					 INA3221_MASK_ENABLE_SCC_MASK,
1014					 ina->summation_channel_control);
1015		if (ret) {
1016			dev_err(dev, "Unable to control summation channel\n");
1017			return ret;
1018		}
1019	}
1020
1021	return 0;
1022}
1023
1024static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume,
1025				 NULL);
1026
1027static const struct of_device_id ina3221_of_match_table[] = {
1028	{ .compatible = "ti,ina3221", },
1029	{ /* sentinel */ }
1030};
1031MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
1032
1033static const struct i2c_device_id ina3221_ids[] = {
1034	{ "ina3221", 0 },
1035	{ /* sentinel */ }
1036};
1037MODULE_DEVICE_TABLE(i2c, ina3221_ids);
1038
1039static struct i2c_driver ina3221_i2c_driver = {
1040	.probe = ina3221_probe,
1041	.remove = ina3221_remove,
1042	.driver = {
1043		.name = INA3221_DRIVER_NAME,
1044		.of_match_table = ina3221_of_match_table,
1045		.pm = pm_ptr(&ina3221_pm),
1046	},
1047	.id_table = ina3221_ids,
1048};
1049module_i2c_driver(ina3221_i2c_driver);
1050
1051MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
1052MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
1053MODULE_LICENSE("GPL v2");
1054