xref: /kernel/linux/linux-6.6/drivers/hwmon/ina3221.c (revision 62306a36)
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/hwmon.h>
10#include <linux/hwmon-sysfs.h>
11#include <linux/i2c.h>
12#include <linux/module.h>
13#include <linux/mutex.h>
14#include <linux/of.h>
15#include <linux/pm_runtime.h>
16#include <linux/regmap.h>
17#include <linux/util_macros.h>
18
19#define INA3221_DRIVER_NAME		"ina3221"
20
21#define INA3221_CONFIG			0x00
22#define INA3221_SHUNT1			0x01
23#define INA3221_BUS1			0x02
24#define INA3221_SHUNT2			0x03
25#define INA3221_BUS2			0x04
26#define INA3221_SHUNT3			0x05
27#define INA3221_BUS3			0x06
28#define INA3221_CRIT1			0x07
29#define INA3221_WARN1			0x08
30#define INA3221_CRIT2			0x09
31#define INA3221_WARN2			0x0a
32#define INA3221_CRIT3			0x0b
33#define INA3221_WARN3			0x0c
34#define INA3221_SHUNT_SUM		0x0d
35#define INA3221_CRIT_SUM		0x0e
36#define INA3221_MASK_ENABLE		0x0f
37
38#define INA3221_CONFIG_MODE_MASK	GENMASK(2, 0)
39#define INA3221_CONFIG_MODE_POWERDOWN	0
40#define INA3221_CONFIG_MODE_SHUNT	BIT(0)
41#define INA3221_CONFIG_MODE_BUS		BIT(1)
42#define INA3221_CONFIG_MODE_CONTINUOUS	BIT(2)
43#define INA3221_CONFIG_VSH_CT_SHIFT	3
44#define INA3221_CONFIG_VSH_CT_MASK	GENMASK(5, 3)
45#define INA3221_CONFIG_VSH_CT(x)	(((x) & GENMASK(5, 3)) >> 3)
46#define INA3221_CONFIG_VBUS_CT_SHIFT	6
47#define INA3221_CONFIG_VBUS_CT_MASK	GENMASK(8, 6)
48#define INA3221_CONFIG_VBUS_CT(x)	(((x) & GENMASK(8, 6)) >> 6)
49#define INA3221_CONFIG_AVG_SHIFT	9
50#define INA3221_CONFIG_AVG_MASK		GENMASK(11, 9)
51#define INA3221_CONFIG_AVG(x)		(((x) & GENMASK(11, 9)) >> 9)
52#define INA3221_CONFIG_CHs_EN_MASK	GENMASK(14, 12)
53#define INA3221_CONFIG_CHx_EN(x)	BIT(14 - (x))
54
55#define INA3221_MASK_ENABLE_SCC_MASK	GENMASK(14, 12)
56
57#define INA3221_CONFIG_DEFAULT		0x7127
58#define INA3221_RSHUNT_DEFAULT		10000
59
60enum ina3221_fields {
61	/* Configuration */
62	F_RST,
63
64	/* Status Flags */
65	F_CVRF,
66
67	/* Warning Flags */
68	F_WF3, F_WF2, F_WF1,
69
70	/* Alert Flags: SF is the summation-alert flag */
71	F_SF, F_CF3, F_CF2, F_CF1,
72
73	/* sentinel */
74	F_MAX_FIELDS
75};
76
77static const struct reg_field ina3221_reg_fields[] = {
78	[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
79
80	[F_CVRF] = REG_FIELD(INA3221_MASK_ENABLE, 0, 0),
81	[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
82	[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
83	[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
84	[F_SF] = REG_FIELD(INA3221_MASK_ENABLE, 6, 6),
85	[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
86	[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
87	[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
88};
89
90enum ina3221_channels {
91	INA3221_CHANNEL1,
92	INA3221_CHANNEL2,
93	INA3221_CHANNEL3,
94	INA3221_NUM_CHANNELS
95};
96
97/**
98 * struct ina3221_input - channel input source specific information
99 * @label: label of channel input source
100 * @shunt_resistor: shunt resistor value of channel input source
101 * @disconnected: connection status of channel input source
102 */
103struct ina3221_input {
104	const char *label;
105	int shunt_resistor;
106	bool disconnected;
107};
108
109/**
110 * struct ina3221_data - device specific information
111 * @pm_dev: Device pointer for pm runtime
112 * @regmap: Register map of the device
113 * @fields: Register fields of the device
114 * @inputs: Array of channel input source specific structures
115 * @lock: mutex lock to serialize sysfs attribute accesses
116 * @reg_config: Register value of INA3221_CONFIG
117 * @summation_shunt_resistor: equivalent shunt resistor value for summation
118 * @single_shot: running in single-shot operating mode
119 */
120struct ina3221_data {
121	struct device *pm_dev;
122	struct regmap *regmap;
123	struct regmap_field *fields[F_MAX_FIELDS];
124	struct ina3221_input inputs[INA3221_NUM_CHANNELS];
125	struct mutex lock;
126	u32 reg_config;
127	int summation_shunt_resistor;
128
129	bool single_shot;
130};
131
132static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
133{
134	/* Summation channel checks shunt resistor values */
135	if (channel > INA3221_CHANNEL3)
136		return ina->summation_shunt_resistor != 0;
137
138	return pm_runtime_active(ina->pm_dev) &&
139	       (ina->reg_config & INA3221_CONFIG_CHx_EN(channel));
140}
141
142/*
143 * Helper function to return the resistor value for current summation.
144 *
145 * There is a condition to calculate current summation -- all the shunt
146 * resistor values should be the same, so as to simply fit the formula:
147 *     current summation = shunt voltage summation / shunt resistor
148 *
149 * Returns the equivalent shunt resistor value on success or 0 on failure
150 */
151static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina)
152{
153	struct ina3221_input *input = ina->inputs;
154	int i, shunt_resistor = 0;
155
156	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
157		if (input[i].disconnected || !input[i].shunt_resistor)
158			continue;
159		if (!shunt_resistor) {
160			/* Found the reference shunt resistor value */
161			shunt_resistor = input[i].shunt_resistor;
162		} else {
163			/* No summation if resistor values are different */
164			if (shunt_resistor != input[i].shunt_resistor)
165				return 0;
166		}
167	}
168
169	return shunt_resistor;
170}
171
172/* Lookup table for Bus and Shunt conversion times in usec */
173static const u16 ina3221_conv_time[] = {
174	140, 204, 332, 588, 1100, 2116, 4156, 8244,
175};
176
177/* Lookup table for number of samples using in averaging mode */
178static const int ina3221_avg_samples[] = {
179	1, 4, 16, 64, 128, 256, 512, 1024,
180};
181
182/* Converting update_interval in msec to conversion time in usec */
183static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval)
184{
185	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
186	u32 samples_idx = INA3221_CONFIG_AVG(config);
187	u32 samples = ina3221_avg_samples[samples_idx];
188
189	/* Bisect the result to Bus and Shunt conversion times */
190	return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples);
191}
192
193/* Converting CONFIG register value to update_interval in usec */
194static inline u32 ina3221_reg_to_interval_us(u16 config)
195{
196	u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
197	u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config);
198	u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config);
199	u32 vbus_ct = ina3221_conv_time[vbus_ct_idx];
200	u32 vsh_ct = ina3221_conv_time[vsh_ct_idx];
201
202	/* Calculate total conversion time */
203	return channels * (vbus_ct + vsh_ct);
204}
205
206static inline int ina3221_wait_for_data(struct ina3221_data *ina)
207{
208	u32 wait, cvrf;
209
210	wait = ina3221_reg_to_interval_us(ina->reg_config);
211
212	/* Polling the CVRF bit to make sure read data is ready */
213	return regmap_field_read_poll_timeout(ina->fields[F_CVRF],
214					      cvrf, cvrf, wait, wait * 2);
215}
216
217static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
218			      int *val)
219{
220	unsigned int regval;
221	int ret;
222
223	ret = regmap_read(ina->regmap, reg, &regval);
224	if (ret)
225		return ret;
226
227	/*
228	 * Shunt Voltage Sum register has 14-bit value with 1-bit shift
229	 * Other Shunt Voltage registers have 12 bits with 3-bit shift
230	 */
231	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
232		*val = sign_extend32(regval >> 1, 14);
233	else
234		*val = sign_extend32(regval >> 3, 12);
235
236	return 0;
237}
238
239static const u8 ina3221_in_reg[] = {
240	INA3221_BUS1,
241	INA3221_BUS2,
242	INA3221_BUS3,
243	INA3221_SHUNT1,
244	INA3221_SHUNT2,
245	INA3221_SHUNT3,
246	INA3221_SHUNT_SUM,
247};
248
249static int ina3221_read_chip(struct device *dev, u32 attr, long *val)
250{
251	struct ina3221_data *ina = dev_get_drvdata(dev);
252	int regval;
253
254	switch (attr) {
255	case hwmon_chip_samples:
256		regval = INA3221_CONFIG_AVG(ina->reg_config);
257		*val = ina3221_avg_samples[regval];
258		return 0;
259	case hwmon_chip_update_interval:
260		/* Return in msec */
261		*val = ina3221_reg_to_interval_us(ina->reg_config);
262		*val = DIV_ROUND_CLOSEST(*val, 1000);
263		return 0;
264	default:
265		return -EOPNOTSUPP;
266	}
267}
268
269static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
270{
271	const bool is_shunt = channel > INA3221_CHANNEL3;
272	struct ina3221_data *ina = dev_get_drvdata(dev);
273	u8 reg = ina3221_in_reg[channel];
274	int regval, ret;
275
276	/*
277	 * Translate shunt channel index to sensor channel index except
278	 * the 7th channel (6 since being 0-aligned) is for summation.
279	 */
280	if (channel != 6)
281		channel %= INA3221_NUM_CHANNELS;
282
283	switch (attr) {
284	case hwmon_in_input:
285		if (!ina3221_is_enabled(ina, channel))
286			return -ENODATA;
287
288		/* Write CONFIG register to trigger a single-shot measurement */
289		if (ina->single_shot) {
290			regmap_write(ina->regmap, INA3221_CONFIG,
291				     ina->reg_config);
292
293			ret = ina3221_wait_for_data(ina);
294			if (ret)
295				return ret;
296		}
297
298		ret = ina3221_read_value(ina, reg, &regval);
299		if (ret)
300			return ret;
301
302		/*
303		 * Scale of shunt voltage (uV): LSB is 40uV
304		 * Scale of bus voltage (mV): LSB is 8mV
305		 */
306		*val = regval * (is_shunt ? 40 : 8);
307		return 0;
308	case hwmon_in_enable:
309		*val = ina3221_is_enabled(ina, channel);
310		return 0;
311	default:
312		return -EOPNOTSUPP;
313	}
314}
315
316static const u8 ina3221_curr_reg[][INA3221_NUM_CHANNELS + 1] = {
317	[hwmon_curr_input] = { INA3221_SHUNT1, INA3221_SHUNT2,
318			       INA3221_SHUNT3, INA3221_SHUNT_SUM },
319	[hwmon_curr_max] = { INA3221_WARN1, INA3221_WARN2, INA3221_WARN3, 0 },
320	[hwmon_curr_crit] = { INA3221_CRIT1, INA3221_CRIT2,
321			      INA3221_CRIT3, INA3221_CRIT_SUM },
322	[hwmon_curr_max_alarm] = { F_WF1, F_WF2, F_WF3, 0 },
323	[hwmon_curr_crit_alarm] = { F_CF1, F_CF2, F_CF3, F_SF },
324};
325
326static int ina3221_read_curr(struct device *dev, u32 attr,
327			     int channel, long *val)
328{
329	struct ina3221_data *ina = dev_get_drvdata(dev);
330	struct ina3221_input *input = ina->inputs;
331	u8 reg = ina3221_curr_reg[attr][channel];
332	int resistance_uo, voltage_nv;
333	int regval, ret;
334
335	if (channel > INA3221_CHANNEL3)
336		resistance_uo = ina->summation_shunt_resistor;
337	else
338		resistance_uo = input[channel].shunt_resistor;
339
340	switch (attr) {
341	case hwmon_curr_input:
342		if (!ina3221_is_enabled(ina, channel))
343			return -ENODATA;
344
345		/* Write CONFIG register to trigger a single-shot measurement */
346		if (ina->single_shot) {
347			regmap_write(ina->regmap, INA3221_CONFIG,
348				     ina->reg_config);
349
350			ret = ina3221_wait_for_data(ina);
351			if (ret)
352				return ret;
353		}
354
355		fallthrough;
356	case hwmon_curr_crit:
357	case hwmon_curr_max:
358		if (!resistance_uo)
359			return -ENODATA;
360
361		ret = ina3221_read_value(ina, reg, &regval);
362		if (ret)
363			return ret;
364
365		/* Scale of shunt voltage: LSB is 40uV (40000nV) */
366		voltage_nv = regval * 40000;
367		/* Return current in mA */
368		*val = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
369		return 0;
370	case hwmon_curr_crit_alarm:
371	case hwmon_curr_max_alarm:
372		/* No actual register read if channel is disabled */
373		if (!ina3221_is_enabled(ina, channel)) {
374			/* Return 0 for alert flags */
375			*val = 0;
376			return 0;
377		}
378		ret = regmap_field_read(ina->fields[reg], &regval);
379		if (ret)
380			return ret;
381		*val = regval;
382		return 0;
383	default:
384		return -EOPNOTSUPP;
385	}
386}
387
388static int ina3221_write_chip(struct device *dev, u32 attr, long val)
389{
390	struct ina3221_data *ina = dev_get_drvdata(dev);
391	int ret, idx;
392	u32 tmp;
393
394	switch (attr) {
395	case hwmon_chip_samples:
396		idx = find_closest(val, ina3221_avg_samples,
397				   ARRAY_SIZE(ina3221_avg_samples));
398
399		tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) |
400		      (idx << INA3221_CONFIG_AVG_SHIFT);
401		ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
402		if (ret)
403			return ret;
404
405		/* Update reg_config accordingly */
406		ina->reg_config = tmp;
407		return 0;
408	case hwmon_chip_update_interval:
409		tmp = ina3221_interval_ms_to_conv_time(ina->reg_config, val);
410		idx = find_closest(tmp, ina3221_conv_time,
411				   ARRAY_SIZE(ina3221_conv_time));
412
413		/* Update Bus and Shunt voltage conversion times */
414		tmp = INA3221_CONFIG_VBUS_CT_MASK | INA3221_CONFIG_VSH_CT_MASK;
415		tmp = (ina->reg_config & ~tmp) |
416		      (idx << INA3221_CONFIG_VBUS_CT_SHIFT) |
417		      (idx << INA3221_CONFIG_VSH_CT_SHIFT);
418		ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
419		if (ret)
420			return ret;
421
422		/* Update reg_config accordingly */
423		ina->reg_config = tmp;
424		return 0;
425	default:
426		return -EOPNOTSUPP;
427	}
428}
429
430static int ina3221_write_curr(struct device *dev, u32 attr,
431			      int channel, long val)
432{
433	struct ina3221_data *ina = dev_get_drvdata(dev);
434	struct ina3221_input *input = ina->inputs;
435	u8 reg = ina3221_curr_reg[attr][channel];
436	int resistance_uo, current_ma, voltage_uv;
437	int regval;
438
439	if (channel > INA3221_CHANNEL3)
440		resistance_uo = ina->summation_shunt_resistor;
441	else
442		resistance_uo = input[channel].shunt_resistor;
443
444	if (!resistance_uo)
445		return -EOPNOTSUPP;
446
447	/* clamp current */
448	current_ma = clamp_val(val,
449			       INT_MIN / resistance_uo,
450			       INT_MAX / resistance_uo);
451
452	voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
453
454	/* clamp voltage */
455	voltage_uv = clamp_val(voltage_uv, -163800, 163800);
456
457	/*
458	 * Formula to convert voltage_uv to register value:
459	 *     regval = (voltage_uv / scale) << shift
460	 * Note:
461	 *     The scale is 40uV for all shunt voltage registers
462	 *     Shunt Voltage Sum register left-shifts 1 bit
463	 *     All other Shunt Voltage registers shift 3 bits
464	 * Results:
465	 *     SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV
466	 *     SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV
467	 */
468	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
469		regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe;
470	else
471		regval = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
472
473	return regmap_write(ina->regmap, reg, regval);
474}
475
476static int ina3221_write_enable(struct device *dev, int channel, bool enable)
477{
478	struct ina3221_data *ina = dev_get_drvdata(dev);
479	u16 config, mask = INA3221_CONFIG_CHx_EN(channel);
480	u16 config_old = ina->reg_config & mask;
481	u32 tmp;
482	int ret;
483
484	config = enable ? mask : 0;
485
486	/* Bypass if enable status is not being changed */
487	if (config_old == config)
488		return 0;
489
490	/* For enabling routine, increase refcount and resume() at first */
491	if (enable) {
492		ret = pm_runtime_resume_and_get(ina->pm_dev);
493		if (ret < 0) {
494			dev_err(dev, "Failed to get PM runtime\n");
495			return ret;
496		}
497	}
498
499	/* Enable or disable the channel */
500	tmp = (ina->reg_config & ~mask) | (config & mask);
501	ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
502	if (ret)
503		goto fail;
504
505	/* Cache the latest config register value */
506	ina->reg_config = tmp;
507
508	/* For disabling routine, decrease refcount or suspend() at last */
509	if (!enable)
510		pm_runtime_put_sync(ina->pm_dev);
511
512	return 0;
513
514fail:
515	if (enable) {
516		dev_err(dev, "Failed to enable channel %d: error %d\n",
517			channel, ret);
518		pm_runtime_put_sync(ina->pm_dev);
519	}
520
521	return ret;
522}
523
524static int ina3221_read(struct device *dev, enum hwmon_sensor_types type,
525			u32 attr, int channel, long *val)
526{
527	struct ina3221_data *ina = dev_get_drvdata(dev);
528	int ret;
529
530	mutex_lock(&ina->lock);
531
532	switch (type) {
533	case hwmon_chip:
534		ret = ina3221_read_chip(dev, attr, val);
535		break;
536	case hwmon_in:
537		/* 0-align channel ID */
538		ret = ina3221_read_in(dev, attr, channel - 1, val);
539		break;
540	case hwmon_curr:
541		ret = ina3221_read_curr(dev, attr, channel, val);
542		break;
543	default:
544		ret = -EOPNOTSUPP;
545		break;
546	}
547
548	mutex_unlock(&ina->lock);
549
550	return ret;
551}
552
553static int ina3221_write(struct device *dev, enum hwmon_sensor_types type,
554			 u32 attr, int channel, long val)
555{
556	struct ina3221_data *ina = dev_get_drvdata(dev);
557	int ret;
558
559	mutex_lock(&ina->lock);
560
561	switch (type) {
562	case hwmon_chip:
563		ret = ina3221_write_chip(dev, attr, val);
564		break;
565	case hwmon_in:
566		/* 0-align channel ID */
567		ret = ina3221_write_enable(dev, channel - 1, val);
568		break;
569	case hwmon_curr:
570		ret = ina3221_write_curr(dev, attr, channel, val);
571		break;
572	default:
573		ret = -EOPNOTSUPP;
574		break;
575	}
576
577	mutex_unlock(&ina->lock);
578
579	return ret;
580}
581
582static int ina3221_read_string(struct device *dev, enum hwmon_sensor_types type,
583			       u32 attr, int channel, const char **str)
584{
585	struct ina3221_data *ina = dev_get_drvdata(dev);
586	int index = channel - 1;
587
588	if (channel == 7)
589		*str = "sum of shunt voltages";
590	else
591		*str = ina->inputs[index].label;
592
593	return 0;
594}
595
596static umode_t ina3221_is_visible(const void *drvdata,
597				  enum hwmon_sensor_types type,
598				  u32 attr, int channel)
599{
600	const struct ina3221_data *ina = drvdata;
601	const struct ina3221_input *input = NULL;
602
603	switch (type) {
604	case hwmon_chip:
605		switch (attr) {
606		case hwmon_chip_samples:
607		case hwmon_chip_update_interval:
608			return 0644;
609		default:
610			return 0;
611		}
612	case hwmon_in:
613		/* Ignore in0_ */
614		if (channel == 0)
615			return 0;
616
617		switch (attr) {
618		case hwmon_in_label:
619			if (channel - 1 <= INA3221_CHANNEL3)
620				input = &ina->inputs[channel - 1];
621			else if (channel == 7)
622				return 0444;
623			/* Hide label node if label is not provided */
624			return (input && input->label) ? 0444 : 0;
625		case hwmon_in_input:
626			return 0444;
627		case hwmon_in_enable:
628			return 0644;
629		default:
630			return 0;
631		}
632	case hwmon_curr:
633		switch (attr) {
634		case hwmon_curr_input:
635		case hwmon_curr_crit_alarm:
636		case hwmon_curr_max_alarm:
637			return 0444;
638		case hwmon_curr_crit:
639		case hwmon_curr_max:
640			return 0644;
641		default:
642			return 0;
643		}
644	default:
645		return 0;
646	}
647}
648
649#define INA3221_HWMON_CURR_CONFIG (HWMON_C_INPUT | \
650				   HWMON_C_CRIT | HWMON_C_CRIT_ALARM | \
651				   HWMON_C_MAX | HWMON_C_MAX_ALARM)
652
653static const struct hwmon_channel_info * const ina3221_info[] = {
654	HWMON_CHANNEL_INFO(chip,
655			   HWMON_C_SAMPLES,
656			   HWMON_C_UPDATE_INTERVAL),
657	HWMON_CHANNEL_INFO(in,
658			   /* 0: dummy, skipped in is_visible */
659			   HWMON_I_INPUT,
660			   /* 1-3: input voltage Channels */
661			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
662			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
663			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
664			   /* 4-6: shunt voltage Channels */
665			   HWMON_I_INPUT,
666			   HWMON_I_INPUT,
667			   HWMON_I_INPUT,
668			   /* 7: summation of shunt voltage channels */
669			   HWMON_I_INPUT | HWMON_I_LABEL),
670	HWMON_CHANNEL_INFO(curr,
671			   /* 1-3: current channels*/
672			   INA3221_HWMON_CURR_CONFIG,
673			   INA3221_HWMON_CURR_CONFIG,
674			   INA3221_HWMON_CURR_CONFIG,
675			   /* 4: summation of current channels */
676			   HWMON_C_INPUT | HWMON_C_CRIT | HWMON_C_CRIT_ALARM),
677	NULL
678};
679
680static const struct hwmon_ops ina3221_hwmon_ops = {
681	.is_visible = ina3221_is_visible,
682	.read_string = ina3221_read_string,
683	.read = ina3221_read,
684	.write = ina3221_write,
685};
686
687static const struct hwmon_chip_info ina3221_chip_info = {
688	.ops = &ina3221_hwmon_ops,
689	.info = ina3221_info,
690};
691
692/* Extra attribute groups */
693static ssize_t ina3221_shunt_show(struct device *dev,
694				  struct device_attribute *attr, char *buf)
695{
696	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
697	struct ina3221_data *ina = dev_get_drvdata(dev);
698	unsigned int channel = sd_attr->index;
699	struct ina3221_input *input = &ina->inputs[channel];
700
701	return sysfs_emit(buf, "%d\n", input->shunt_resistor);
702}
703
704static ssize_t ina3221_shunt_store(struct device *dev,
705				   struct device_attribute *attr,
706				   const char *buf, size_t count)
707{
708	struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
709	struct ina3221_data *ina = dev_get_drvdata(dev);
710	unsigned int channel = sd_attr->index;
711	struct ina3221_input *input = &ina->inputs[channel];
712	int val;
713	int ret;
714
715	ret = kstrtoint(buf, 0, &val);
716	if (ret)
717		return ret;
718
719	val = clamp_val(val, 1, INT_MAX);
720
721	input->shunt_resistor = val;
722
723	/* Update summation_shunt_resistor for summation channel */
724	ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
725
726	return count;
727}
728
729/* shunt resistance */
730static SENSOR_DEVICE_ATTR_RW(shunt1_resistor, ina3221_shunt, INA3221_CHANNEL1);
731static SENSOR_DEVICE_ATTR_RW(shunt2_resistor, ina3221_shunt, INA3221_CHANNEL2);
732static SENSOR_DEVICE_ATTR_RW(shunt3_resistor, ina3221_shunt, INA3221_CHANNEL3);
733
734static struct attribute *ina3221_attrs[] = {
735	&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
736	&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
737	&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
738	NULL,
739};
740ATTRIBUTE_GROUPS(ina3221);
741
742static const struct regmap_range ina3221_yes_ranges[] = {
743	regmap_reg_range(INA3221_CONFIG, INA3221_BUS3),
744	regmap_reg_range(INA3221_SHUNT_SUM, INA3221_SHUNT_SUM),
745	regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
746};
747
748static const struct regmap_access_table ina3221_volatile_table = {
749	.yes_ranges = ina3221_yes_ranges,
750	.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
751};
752
753static const struct regmap_config ina3221_regmap_config = {
754	.reg_bits = 8,
755	.val_bits = 16,
756
757	.cache_type = REGCACHE_RBTREE,
758	.volatile_table = &ina3221_volatile_table,
759};
760
761static int ina3221_probe_child_from_dt(struct device *dev,
762				       struct device_node *child,
763				       struct ina3221_data *ina)
764{
765	struct ina3221_input *input;
766	u32 val;
767	int ret;
768
769	ret = of_property_read_u32(child, "reg", &val);
770	if (ret) {
771		dev_err(dev, "missing reg property of %pOFn\n", child);
772		return ret;
773	} else if (val > INA3221_CHANNEL3) {
774		dev_err(dev, "invalid reg %d of %pOFn\n", val, child);
775		return -EINVAL;
776	}
777
778	input = &ina->inputs[val];
779
780	/* Log the disconnected channel input */
781	if (!of_device_is_available(child)) {
782		input->disconnected = true;
783		return 0;
784	}
785
786	/* Save the connected input label if available */
787	of_property_read_string(child, "label", &input->label);
788
789	/* Overwrite default shunt resistor value optionally */
790	if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) {
791		if (val < 1 || val > INT_MAX) {
792			dev_err(dev, "invalid shunt resistor value %u of %pOFn\n",
793				val, child);
794			return -EINVAL;
795		}
796		input->shunt_resistor = val;
797	}
798
799	return 0;
800}
801
802static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
803{
804	const struct device_node *np = dev->of_node;
805	struct device_node *child;
806	int ret;
807
808	/* Compatible with non-DT platforms */
809	if (!np)
810		return 0;
811
812	ina->single_shot = of_property_read_bool(np, "ti,single-shot");
813
814	for_each_child_of_node(np, child) {
815		ret = ina3221_probe_child_from_dt(dev, child, ina);
816		if (ret) {
817			of_node_put(child);
818			return ret;
819		}
820	}
821
822	return 0;
823}
824
825static int ina3221_probe(struct i2c_client *client)
826{
827	struct device *dev = &client->dev;
828	struct ina3221_data *ina;
829	struct device *hwmon_dev;
830	int i, ret;
831
832	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
833	if (!ina)
834		return -ENOMEM;
835
836	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
837	if (IS_ERR(ina->regmap)) {
838		dev_err(dev, "Unable to allocate register map\n");
839		return PTR_ERR(ina->regmap);
840	}
841
842	for (i = 0; i < F_MAX_FIELDS; i++) {
843		ina->fields[i] = devm_regmap_field_alloc(dev,
844							 ina->regmap,
845							 ina3221_reg_fields[i]);
846		if (IS_ERR(ina->fields[i])) {
847			dev_err(dev, "Unable to allocate regmap fields\n");
848			return PTR_ERR(ina->fields[i]);
849		}
850	}
851
852	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
853		ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT;
854
855	ret = ina3221_probe_from_dt(dev, ina);
856	if (ret) {
857		dev_err(dev, "Unable to probe from device tree\n");
858		return ret;
859	}
860
861	/* The driver will be reset, so use reset value */
862	ina->reg_config = INA3221_CONFIG_DEFAULT;
863
864	/* Clear continuous bit to use single-shot mode */
865	if (ina->single_shot)
866		ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
867
868	/* Disable channels if their inputs are disconnected */
869	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
870		if (ina->inputs[i].disconnected)
871			ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i);
872	}
873
874	/* Initialize summation_shunt_resistor for summation channel control */
875	ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
876
877	ina->pm_dev = dev;
878	mutex_init(&ina->lock);
879	dev_set_drvdata(dev, ina);
880
881	/* Enable PM runtime -- status is suspended by default */
882	pm_runtime_enable(ina->pm_dev);
883
884	/* Initialize (resume) the device */
885	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
886		if (ina->inputs[i].disconnected)
887			continue;
888		/* Match the refcount with number of enabled channels */
889		ret = pm_runtime_get_sync(ina->pm_dev);
890		if (ret < 0)
891			goto fail;
892	}
893
894	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina,
895							 &ina3221_chip_info,
896							 ina3221_groups);
897	if (IS_ERR(hwmon_dev)) {
898		dev_err(dev, "Unable to register hwmon device\n");
899		ret = PTR_ERR(hwmon_dev);
900		goto fail;
901	}
902
903	return 0;
904
905fail:
906	pm_runtime_disable(ina->pm_dev);
907	pm_runtime_set_suspended(ina->pm_dev);
908	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
909	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
910		pm_runtime_put_noidle(ina->pm_dev);
911	mutex_destroy(&ina->lock);
912
913	return ret;
914}
915
916static void ina3221_remove(struct i2c_client *client)
917{
918	struct ina3221_data *ina = dev_get_drvdata(&client->dev);
919	int i;
920
921	pm_runtime_disable(ina->pm_dev);
922	pm_runtime_set_suspended(ina->pm_dev);
923
924	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
925	for (i = 0; i < INA3221_NUM_CHANNELS; i++)
926		pm_runtime_put_noidle(ina->pm_dev);
927
928	mutex_destroy(&ina->lock);
929}
930
931static int ina3221_suspend(struct device *dev)
932{
933	struct ina3221_data *ina = dev_get_drvdata(dev);
934	int ret;
935
936	/* Save config register value and enable cache-only */
937	ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config);
938	if (ret)
939		return ret;
940
941	/* Set to power-down mode for power saving */
942	ret = regmap_update_bits(ina->regmap, INA3221_CONFIG,
943				 INA3221_CONFIG_MODE_MASK,
944				 INA3221_CONFIG_MODE_POWERDOWN);
945	if (ret)
946		return ret;
947
948	regcache_cache_only(ina->regmap, true);
949	regcache_mark_dirty(ina->regmap);
950
951	return 0;
952}
953
954static int ina3221_resume(struct device *dev)
955{
956	struct ina3221_data *ina = dev_get_drvdata(dev);
957	int ret;
958
959	regcache_cache_only(ina->regmap, false);
960
961	/* Software reset the chip */
962	ret = regmap_field_write(ina->fields[F_RST], true);
963	if (ret) {
964		dev_err(dev, "Unable to reset device\n");
965		return ret;
966	}
967
968	/* Restore cached register values to hardware */
969	ret = regcache_sync(ina->regmap);
970	if (ret)
971		return ret;
972
973	/* Restore config register value to hardware */
974	ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config);
975	if (ret)
976		return ret;
977
978	/* Initialize summation channel control */
979	if (ina->summation_shunt_resistor) {
980		/*
981		 * Take all three channels into summation by default
982		 * Shunt measurements of disconnected channels should
983		 * be 0, so it does not matter for summation.
984		 */
985		ret = regmap_update_bits(ina->regmap, INA3221_MASK_ENABLE,
986					 INA3221_MASK_ENABLE_SCC_MASK,
987					 INA3221_MASK_ENABLE_SCC_MASK);
988		if (ret) {
989			dev_err(dev, "Unable to control summation channel\n");
990			return ret;
991		}
992	}
993
994	return 0;
995}
996
997static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume,
998				 NULL);
999
1000static const struct of_device_id ina3221_of_match_table[] = {
1001	{ .compatible = "ti,ina3221", },
1002	{ /* sentinel */ }
1003};
1004MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
1005
1006static const struct i2c_device_id ina3221_ids[] = {
1007	{ "ina3221", 0 },
1008	{ /* sentinel */ }
1009};
1010MODULE_DEVICE_TABLE(i2c, ina3221_ids);
1011
1012static struct i2c_driver ina3221_i2c_driver = {
1013	.probe = ina3221_probe,
1014	.remove = ina3221_remove,
1015	.driver = {
1016		.name = INA3221_DRIVER_NAME,
1017		.of_match_table = ina3221_of_match_table,
1018		.pm = pm_ptr(&ina3221_pm),
1019	},
1020	.id_table = ina3221_ids,
1021};
1022module_i2c_driver(ina3221_i2c_driver);
1023
1024MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
1025MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
1026MODULE_LICENSE("GPL v2");
1027