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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * INA3221 Triple Current/Voltage Monitor4 *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			0x0023#define INA3221_SHUNT1			0x0124#define INA3221_BUS1			0x0225#define INA3221_SHUNT2			0x0326#define INA3221_BUS2			0x0427#define INA3221_SHUNT3			0x0528#define INA3221_BUS3			0x0629#define INA3221_CRIT1			0x0730#define INA3221_WARN1			0x0831#define INA3221_CRIT2			0x0932#define INA3221_WARN2			0x0a33#define INA3221_CRIT3			0x0b34#define INA3221_WARN3			0x0c35#define INA3221_SHUNT_SUM		0x0d36#define INA3221_CRIT_SUM		0x0e37#define INA3221_MASK_ENABLE		0x0f38 39#define INA3221_CONFIG_MODE_MASK	GENMASK(2, 0)40#define INA3221_CONFIG_MODE_POWERDOWN	041#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	345#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	648#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	951#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		0x712759#define INA3221_RSHUNT_DEFAULT		1000060 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_FIELDS76};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_CHANNELS96};97 98/**99 * struct ina3221_input - channel input source specific information100 * @label: label of channel input source101 * @shunt_resistor: shunt resistor value of channel input source102 * @disconnected: connection status of channel input source103 * @summation_disable: channel summation status of input source104 */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 information114 * @pm_dev: Device pointer for pm runtime115 * @regmap: Register map of the device116 * @fields: Register fields of the device117 * @inputs: Array of channel input source specific structures118 * @lock: mutex lock to serialize sysfs attribute accesses119 * @debugfs: Pointer to debugfs entry for device120 * @reg_config: Register value of INA3221_CONFIG121 * @summation_shunt_resistor: equivalent shunt resistor value for summation122 * @summation_channel_control: Value written to SCC field in INA3221_MASK_ENABLE123 * @single_shot: running in single-shot operating mode124 */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 shunt153 * resistor values should be the same, so as to simply fit the formula:154 *     current summation = shunt voltage summation / shunt resistor155 *156 * Returns the equivalent shunt resistor value on success or 0 on failure157 */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 shift237	 * Other Shunt Voltage registers have 12 bits with 3-bit shift238	 */239	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)240		*val = sign_extend32(regval >> 1, 14);241	else242		*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 except286	 * 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 40uV312		 * Scale of bus voltage (mV): LSB is 8mV313		 */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	else346		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	else450		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) << shift468	 * Note:469	 *     The scale is 40uV for all shunt voltage registers470	 *     Shunt Voltage Sum register left-shifts 1 bit471	 *     All other Shunt Voltage registers shift 3 bits472	 * Results:473	 *     SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV474	 *     SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV475	 */476	if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)477		regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe;478	else479		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	else599		*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	NULL686};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	int ret;817 818	/* Compatible with non-DT platforms */819	if (!np)820		return 0;821 822	ina->single_shot = of_property_read_bool(np, "ti,single-shot");823 824	for_each_child_of_node_scoped(np, child) {825		ret = ina3221_probe_child_from_dt(dev, child, ina);826		if (ret)827			return ret;828	}829 830	return 0;831}832 833static int ina3221_probe(struct i2c_client *client)834{835	struct device *dev = &client->dev;836	struct ina3221_data *ina;837	struct device *hwmon_dev;838	char name[32];839	int i, ret;840 841	ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);842	if (!ina)843		return -ENOMEM;844 845	ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);846	if (IS_ERR(ina->regmap)) {847		dev_err(dev, "Unable to allocate register map\n");848		return PTR_ERR(ina->regmap);849	}850 851	for (i = 0; i < F_MAX_FIELDS; i++) {852		ina->fields[i] = devm_regmap_field_alloc(dev,853							 ina->regmap,854							 ina3221_reg_fields[i]);855		if (IS_ERR(ina->fields[i])) {856			dev_err(dev, "Unable to allocate regmap fields\n");857			return PTR_ERR(ina->fields[i]);858		}859	}860 861	for (i = 0; i < INA3221_NUM_CHANNELS; i++)862		ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT;863 864	ret = ina3221_probe_from_dt(dev, ina);865	if (ret) {866		dev_err(dev, "Unable to probe from device tree\n");867		return ret;868	}869 870	/* The driver will be reset, so use reset value */871	ina->reg_config = INA3221_CONFIG_DEFAULT;872 873	/* Clear continuous bit to use single-shot mode */874	if (ina->single_shot)875		ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;876 877	/* Disable channels if their inputs are disconnected */878	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {879		if (ina->inputs[i].disconnected)880			ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i);881	}882 883	/* Initialize summation_shunt_resistor for summation channel control */884	ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);885	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {886		if (!ina->inputs[i].summation_disable)887			ina->summation_channel_control |= BIT(14 - i);888	}889 890	ina->pm_dev = dev;891	mutex_init(&ina->lock);892	dev_set_drvdata(dev, ina);893 894	/* Enable PM runtime -- status is suspended by default */895	pm_runtime_enable(ina->pm_dev);896 897	/* Initialize (resume) the device */898	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {899		if (ina->inputs[i].disconnected)900			continue;901		/* Match the refcount with number of enabled channels */902		ret = pm_runtime_get_sync(ina->pm_dev);903		if (ret < 0)904			goto fail;905	}906 907	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina,908							 &ina3221_chip_info,909							 ina3221_groups);910	if (IS_ERR(hwmon_dev)) {911		dev_err(dev, "Unable to register hwmon device\n");912		ret = PTR_ERR(hwmon_dev);913		goto fail;914	}915 916	scnprintf(name, sizeof(name), "%s-%s", INA3221_DRIVER_NAME, dev_name(dev));917	ina->debugfs = debugfs_create_dir(name, NULL);918 919	for (i = 0; i < INA3221_NUM_CHANNELS; i++) {920		scnprintf(name, sizeof(name), "in%d_summation_disable", i);921		debugfs_create_bool(name, 0400, ina->debugfs,922				    &ina->inputs[i].summation_disable);923	}924 925	return 0;926 927fail:928	pm_runtime_disable(ina->pm_dev);929	pm_runtime_set_suspended(ina->pm_dev);930	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */931	for (i = 0; i < INA3221_NUM_CHANNELS; i++)932		pm_runtime_put_noidle(ina->pm_dev);933	mutex_destroy(&ina->lock);934 935	return ret;936}937 938static void ina3221_remove(struct i2c_client *client)939{940	struct ina3221_data *ina = dev_get_drvdata(&client->dev);941	int i;942 943	debugfs_remove_recursive(ina->debugfs);944 945	pm_runtime_disable(ina->pm_dev);946	pm_runtime_set_suspended(ina->pm_dev);947 948	/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */949	for (i = 0; i < INA3221_NUM_CHANNELS; i++)950		pm_runtime_put_noidle(ina->pm_dev);951 952	mutex_destroy(&ina->lock);953}954 955static int ina3221_suspend(struct device *dev)956{957	struct ina3221_data *ina = dev_get_drvdata(dev);958	int ret;959 960	/* Save config register value and enable cache-only */961	ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config);962	if (ret)963		return ret;964 965	/* Set to power-down mode for power saving */966	ret = regmap_update_bits(ina->regmap, INA3221_CONFIG,967				 INA3221_CONFIG_MODE_MASK,968				 INA3221_CONFIG_MODE_POWERDOWN);969	if (ret)970		return ret;971 972	regcache_cache_only(ina->regmap, true);973	regcache_mark_dirty(ina->regmap);974 975	return 0;976}977 978static int ina3221_resume(struct device *dev)979{980	struct ina3221_data *ina = dev_get_drvdata(dev);981	int ret;982 983	regcache_cache_only(ina->regmap, false);984 985	/* Software reset the chip */986	ret = regmap_field_write(ina->fields[F_RST], true);987	if (ret) {988		dev_err(dev, "Unable to reset device\n");989		return ret;990	}991 992	/* Restore cached register values to hardware */993	ret = regcache_sync(ina->regmap);994	if (ret)995		return ret;996 997	/* Restore config register value to hardware */998	ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config);999	if (ret)1000		return ret;1001 1002	/* Initialize summation channel control */1003	if (ina->summation_shunt_resistor) {1004		/*1005		 * Sum only channels that are not disabled for summation.1006		 * Shunt measurements of disconnected channels should1007		 * be 0, so it does not matter for summation.1008		 */1009		ret = regmap_update_bits(ina->regmap, INA3221_MASK_ENABLE,1010					 INA3221_MASK_ENABLE_SCC_MASK,1011					 ina->summation_channel_control);1012		if (ret) {1013			dev_err(dev, "Unable to control summation channel\n");1014			return ret;1015		}1016	}1017 1018	return 0;1019}1020 1021static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume,1022				 NULL);1023 1024static const struct of_device_id ina3221_of_match_table[] = {1025	{ .compatible = "ti,ina3221", },1026	{ /* sentinel */ }1027};1028MODULE_DEVICE_TABLE(of, ina3221_of_match_table);1029 1030static const struct i2c_device_id ina3221_ids[] = {1031	{ "ina3221" },1032	{ /* sentinel */ }1033};1034MODULE_DEVICE_TABLE(i2c, ina3221_ids);1035 1036static struct i2c_driver ina3221_i2c_driver = {1037	.probe = ina3221_probe,1038	.remove = ina3221_remove,1039	.driver = {1040		.name = INA3221_DRIVER_NAME,1041		.of_match_table = ina3221_of_match_table,1042		.pm = pm_ptr(&ina3221_pm),1043	},1044	.id_table = ina3221_ids,1045};1046module_i2c_driver(ina3221_i2c_driver);1047 1048MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");1049MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");1050MODULE_LICENSE("GPL v2");1051