drivers/hwmon/max31760.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only

 #include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/err.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/i2c.h>
 #include <linux/regmap.h>
 #include <linux/util_macros.h>

 #define REG_CR1		0x00
 #define CR1_HYST	BIT(5)
 #define CR1_DRV		GENMASK(4, 3)
 #define CR1_TEMP_SRC	GENMASK(1, 0)
 #define REG_CR2		0x01
 #define CR2_STBY	BIT(7)
 #define CR2_ALERTS	BIT(6)
 #define CR2_DFC		BIT(0)
 #define REG_CR3		0x02
 #define REG_PWMR	0x50
 #define REG_PWMV	0x51
 #define REG_STATUS	0x5A
 #define STATUS_ALARM_CRIT(ch)	BIT(2 + 2 * (ch))
 #define STATUS_ALARM_MAX(ch)	BIT(3 + 2 * (ch))
 #define STATUS_RDFA		BIT(6)

 #define REG_TACH(ch)		(0x52 + (ch) * 2)
 #define REG_TEMP_INPUT(ch)	(0x56 + (ch) * 2)
 #define REG_TEMP_MAX(ch)	(0x06 + (ch) * 2)
 #define REG_TEMP_CRIT(ch)	(0x0A + (ch) * 2)

 #define TEMP11_FROM_REG(reg)	((reg) / 32 * 125)
 #define TEMP11_TO_REG(val)	(DIV_ROUND_CLOSEST(clamp_val((val), -128000, \
 							     127875), 125) * 32)

 #define LUT_SIZE	48

 #define REG_LUT(index)		(0x20 + (index))

 struct max31760_state {
 	struct regmap *regmap;

 	struct lut_attribute {
 		char name[24];
 		struct sensor_device_attribute sda;
 	} lut[LUT_SIZE];

 	struct attribute *attrs[LUT_SIZE + 2];
 	struct attribute_group group;
 	const struct attribute_group *groups[2];
 };

 static bool max31760_volatile_reg(struct device *dev, unsigned int reg)
 {
 	return reg > 0x50;
 }

 static const struct regmap_config regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = 0x5B,
 	.cache_type = REGCACHE_RBTREE,
 	.volatile_reg = max31760_volatile_reg,
 };

 static const int max31760_pwm_freq[] = {33, 150, 1500, 25000};

 static int tach_to_rpm(u16 tach)
 {
 	if (tach == 0)
 		tach = 1;

 	return 60 * 100000 / tach / 2;
 }

 static int max31760_read(struct device *dev, enum hwmon_sensor_types type,
 			 u32 attr, int channel, long *val)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);
 	unsigned int regval;
 	unsigned int reg_temp;
 	s16 temp;
 	u8 reg[2];
 	int ret;

 	switch (type) {
 	case hwmon_temp:
 		switch (attr) {
 		case hwmon_temp_fault:
 			ret = regmap_read(state->regmap, REG_STATUS, &regval);
 			if (ret)
 				return ret;

 			*val = FIELD_GET(STATUS_RDFA, regval);

 			return 0;
 		case hwmon_temp_max_alarm:
 			ret = regmap_read(state->regmap, REG_STATUS, &regval);
 			if (ret)
 				return ret;

 			if (channel)
 				*val = FIELD_GET(STATUS_ALARM_MAX(1), regval);
 			else
 				*val = FIELD_GET(STATUS_ALARM_MAX(0), regval);

 			return 0;
 		case hwmon_temp_crit_alarm:
 			ret = regmap_read(state->regmap, REG_STATUS, &regval);
 			if (ret)
 				return ret;

 			if (channel)
 				*val = FIELD_GET(STATUS_ALARM_CRIT(1), regval);
 			else
 				*val = FIELD_GET(STATUS_ALARM_CRIT(0), regval);

 			return 0;
 		case hwmon_temp_input:
 			reg_temp = REG_TEMP_INPUT(channel);
 			break;
 		case hwmon_temp_max:
 			reg_temp = REG_TEMP_MAX(channel);
 			break;
 		case hwmon_temp_crit:
 			reg_temp = REG_TEMP_CRIT(channel);
 			break;
 		default:
 			return -EOPNOTSUPP;
 		}

 		ret = regmap_bulk_read(state->regmap, reg_temp, reg, 2);
 		if (ret)
 			return ret;

 		temp = (reg[0] << 8) | reg[1];

 		*val = TEMP11_FROM_REG(temp);

 		return 0;
 	case hwmon_fan:
 		switch (attr) {
 		case hwmon_fan_input:
 			ret = regmap_bulk_read(state->regmap, REG_TACH(channel), reg, 2);
 			if (ret)
 				return ret;

 			*val = tach_to_rpm(reg[0] * 256 + reg[1]);

 			return 0;
 		case hwmon_fan_fault:
 			ret = regmap_read(state->regmap, REG_STATUS, &regval);
 			if (ret)
 				return ret;

 			if (channel)
 				*val = FIELD_GET(BIT(1), regval);
 			else
 				*val = FIELD_GET(BIT(0), regval);

 			return 0;
 		case hwmon_fan_enable:
 			ret = regmap_read(state->regmap, REG_CR3, &regval);
 			if (ret)
 				return ret;

 			if (channel)
 				*val = FIELD_GET(BIT(1), regval);
 			else
 				*val = FIELD_GET(BIT(0), regval);

 			return 0;
 		default:
 			return -EOPNOTSUPP;
 		}
 	case hwmon_pwm:
 		switch (attr) {
 		case hwmon_pwm_input:
 			ret = regmap_read(state->regmap, REG_PWMV, &regval);
 			if (ret)
 				return ret;

 			*val = regval;

 			return 0;
 		case hwmon_pwm_freq:
 			ret = regmap_read(state->regmap, REG_CR1, &regval);
 			if (ret)
 				return ret;

 			regval = FIELD_GET(CR1_DRV, regval);
 			if (regval >= ARRAY_SIZE(max31760_pwm_freq))
 				return -EINVAL;

 			*val = max31760_pwm_freq[regval];

 			return 0;
 		case hwmon_pwm_enable:
 			ret = regmap_read(state->regmap, REG_CR2, &regval);
 			if (ret)
 				return ret;

 			*val = 2 - FIELD_GET(CR2_DFC, regval);

 			return 0;
 		case hwmon_pwm_auto_channels_temp:
 			ret = regmap_read(state->regmap, REG_CR1, &regval);
 			if (ret)
 				return ret;

 			switch (FIELD_GET(CR1_TEMP_SRC, regval)) {
 			case 0:
 				*val = 2;
 				break;
 			case 1:
 				*val = 1;
 				break;
 			case 2:
 			case 3:
 				*val = 3;
 				break;
 			default:
 				return -EINVAL;
 			}

 			return 0;
 		default:
 			return -EOPNOTSUPP;
 		}
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static int max31760_write(struct device *dev, enum hwmon_sensor_types type,
 			  u32 attr, int channel, long val)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);
 	unsigned int pwm_index;
 	unsigned int reg_temp;
 	int temp;
 	u8 reg_val[2];

 	switch (type) {
 	case hwmon_temp:
 		switch (attr) {
 		case hwmon_temp_max:
 			reg_temp = REG_TEMP_MAX(channel);
 			break;
 		case hwmon_temp_crit:
 			reg_temp = REG_TEMP_CRIT(channel);
 			break;
 		default:
 			return -EOPNOTSUPP;
 		}

 		temp = TEMP11_TO_REG(val);
 		reg_val[0] = temp >> 8;
 		reg_val[1] = temp & 0xFF;

 		return regmap_bulk_write(state->regmap, reg_temp, reg_val, 2);
 	case hwmon_fan:
 		switch (attr) {
 		case hwmon_fan_enable:
 			if (val == 0)
 				return regmap_clear_bits(state->regmap, REG_CR3, BIT(channel));

 			if (val == 1)
 				return regmap_set_bits(state->regmap, REG_CR3, BIT(channel));

 			return -EINVAL;
 		default:
 			return -EOPNOTSUPP;
 		}
 	case hwmon_pwm:
 		switch (attr) {
 		case hwmon_pwm_input:
 			if (val < 0 || val > 255)
 				return -EINVAL;

 			return regmap_write(state->regmap, REG_PWMR, val);
 		case hwmon_pwm_enable:
 			if (val == 1)
 				return regmap_set_bits(state->regmap, REG_CR2, CR2_DFC);

 			if (val == 2)
 				return regmap_clear_bits(state->regmap, REG_CR2, CR2_DFC);

 			return -EINVAL;
 		case hwmon_pwm_freq:
 			pwm_index = find_closest(val, max31760_pwm_freq,
 						 ARRAY_SIZE(max31760_pwm_freq));

 			return regmap_update_bits(state->regmap,
 						  REG_CR1, CR1_DRV,
 						  FIELD_PREP(CR1_DRV, pwm_index));
 		case hwmon_pwm_auto_channels_temp:
 			switch (val) {
 			case 1:
 				break;
 			case 2:
 				val = 0;
 				break;
 			case 3:
 				val = 2;
 				break;
 			default:
 				return -EINVAL;
 			}

 			return regmap_update_bits(state->regmap, REG_CR1, CR1_TEMP_SRC, val);
 		default:
 			return -EOPNOTSUPP;
 		}
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static const struct hwmon_channel_info * const max31760_info[] = {
 	HWMON_CHANNEL_INFO(chip,
 			   HWMON_C_REGISTER_TZ),
 	HWMON_CHANNEL_INFO(fan,
 			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_ENABLE,
 			   HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_ENABLE),
 	HWMON_CHANNEL_INFO(temp,
 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT |
 			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
 			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_LABEL),
 	HWMON_CHANNEL_INFO(pwm,
 			   HWMON_PWM_ENABLE | HWMON_PWM_FREQ | HWMON_PWM_INPUT |
 			   HWMON_PWM_AUTO_CHANNELS_TEMP),
 	NULL
 };

 static umode_t max31760_is_visible(const void *data,
 				   enum hwmon_sensor_types type,
 				   u32 attr, int channel)
 {
 	switch (type) {
 	case hwmon_temp:
 		switch (attr) {
 		case hwmon_temp_input:
 		case hwmon_temp_max_alarm:
 		case hwmon_temp_crit_alarm:
 		case hwmon_temp_fault:
 		case hwmon_temp_label:
 			return 0444;
 		case hwmon_temp_max:
 		case hwmon_temp_crit:
 			return 0644;
 		default:
 			return 0;
 		}
 	case hwmon_fan:
 		switch (attr) {
 		case hwmon_fan_input:
 		case hwmon_fan_fault:
 			return 0444;
 		case hwmon_fan_enable:
 			return 0644;
 		default:
 			return 0;
 		}
 	case hwmon_pwm:
 		switch (attr) {
 		case hwmon_pwm_enable:
 		case hwmon_pwm_input:
 		case hwmon_pwm_freq:
 		case hwmon_pwm_auto_channels_temp:
 			return 0644;
 		default:
 			return 0;
 		}
 	default:
 		return 0;
 	}
 }

 static int max31760_read_string(struct device *dev,
 				enum hwmon_sensor_types type,
 				u32 attr, int channel, const char **str)
 {
 	switch (type) {
 	case hwmon_temp:
 		if (attr != hwmon_temp_label)
 			return -EOPNOTSUPP;

 		*str = channel ? "local" : "remote";

 		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static const struct hwmon_ops max31760_hwmon_ops = {
 	.is_visible = max31760_is_visible,
 	.read = max31760_read,
 	.write = max31760_write,
 	.read_string = max31760_read_string
 };

 static const struct hwmon_chip_info max31760_chip_info = {
 	.ops = &max31760_hwmon_ops,
 	.info = max31760_info,
 };

 static ssize_t lut_show(struct device *dev,
 			struct device_attribute *devattr, char *buf)
 {
 	struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
 	struct max31760_state *state = dev_get_drvdata(dev);
 	int ret;
 	unsigned int regval;

 	ret = regmap_read(state->regmap, REG_LUT(sda->index), &regval);
 	if (ret)
 		return ret;

 	return sysfs_emit(buf, "%d\n", regval);
 }

 static ssize_t lut_store(struct device *dev,
 			 struct device_attribute *devattr,
 			 const char *buf, size_t count)
 {
 	struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
 	struct max31760_state *state = dev_get_drvdata(dev);
 	int ret;
 	u8 pwm;

 	ret = kstrtou8(buf, 10, &pwm);
 	if (ret)
 		return ret;

 	ret = regmap_write(state->regmap, REG_LUT(sda->index), pwm);
 	if (ret)
 		return ret;

 	return count;
 }

 static ssize_t pwm1_auto_point_temp_hyst_show(struct device *dev,
 					      struct device_attribute *attr,
 					      char *buf)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);
 	unsigned int regval;
 	int ret;

 	ret = regmap_read(state->regmap, REG_CR1, &regval);
 	if (ret)
 		return ret;

 	return sysfs_emit(buf, "%d\n", (1 + (int)FIELD_GET(CR1_HYST, regval)) * 2000);
 }

 static ssize_t pwm1_auto_point_temp_hyst_store(struct device *dev,
 					       struct device_attribute *attr,
 					       const char *buf,
 					       size_t count)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);
 	unsigned int hyst;
 	int ret;

 	ret = kstrtou32(buf, 10, &hyst);
 	if (ret)
 		return ret;

 	if (hyst < 3000)
 		ret = regmap_clear_bits(state->regmap, REG_CR1, CR1_HYST);
 	else
 		ret = regmap_set_bits(state->regmap, REG_CR1, CR1_HYST);

 	if (ret)
 		return ret;

 	return count;
 }

 static DEVICE_ATTR_RW(pwm1_auto_point_temp_hyst);

 static void max31760_create_lut_nodes(struct max31760_state *state)
 {
 	int i;
 	struct sensor_device_attribute *sda;
 	struct lut_attribute *lut;

 	for (i = 0; i < LUT_SIZE; ++i) {
 		lut = &state->lut[i];
 		sda = &lut->sda;

 		snprintf(lut->name, sizeof(lut->name),
 			 "pwm1_auto_point%d_pwm", i + 1);

 		sda->dev_attr.attr.mode = 0644;
 		sda->index = i;
 		sda->dev_attr.show = lut_show;
 		sda->dev_attr.store = lut_store;
 		sda->dev_attr.attr.name = lut->name;

 		sysfs_attr_init(&sda->dev_attr.attr);

 		state->attrs[i] = &sda->dev_attr.attr;
 	}

 	state->attrs[i] = &dev_attr_pwm1_auto_point_temp_hyst.attr;

 	state->group.attrs = state->attrs;
 	state->groups[0] = &state->group;
 }

 static int max31760_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
 	struct max31760_state *state;
 	struct device *hwmon_dev;
 	int ret;

 	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 	if (!state)
 		return -ENOMEM;

 	state->regmap = devm_regmap_init_i2c(client, &regmap_config);
 	if (IS_ERR(state->regmap))
 		return dev_err_probe(dev,
 				     PTR_ERR(state->regmap),
 				     "regmap initialization failed\n");

 	dev_set_drvdata(dev, state);

 	/* Set alert output to comparator mode */
 	ret = regmap_set_bits(state->regmap, REG_CR2, CR2_ALERTS);
 	if (ret)
 		return dev_err_probe(dev, ret, "cannot write register\n");

 	max31760_create_lut_nodes(state);

 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 state,
 							 &max31760_chip_info,
 							 state->groups);

 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static const struct of_device_id max31760_of_match[] = {
 	{.compatible = "adi,max31760"},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, max31760_of_match);

 static const struct i2c_device_id max31760_id[] = {
 	{"max31760"},
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, max31760_id);

 static int max31760_suspend(struct device *dev)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);

 	return regmap_set_bits(state->regmap, REG_CR2, CR2_STBY);
 }

 static int max31760_resume(struct device *dev)
 {
 	struct max31760_state *state = dev_get_drvdata(dev);

 	return regmap_clear_bits(state->regmap, REG_CR2, CR2_STBY);
 }

 static DEFINE_SIMPLE_DEV_PM_OPS(max31760_pm_ops, max31760_suspend,
 				max31760_resume);

 static struct i2c_driver max31760_driver = {
 	.class		= I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "max31760",
 		.of_match_table = max31760_of_match,
 		.pm = pm_ptr(&max31760_pm_ops)
 	},
 	.probe		= max31760_probe,
 	.id_table	= max31760_id
 };
 module_i2c_driver(max31760_driver);

 MODULE_AUTHOR("Ibrahim Tilki <Ibrahim.Tilki@analog.com>");
 MODULE_DESCRIPTION("Analog Devices MAX31760 Fan Speed Controller");
 MODULE_SOFTDEP("pre: regmap_i2c");
 MODULE_VERSION("1.0");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-only

	#include <linux/bitfield.h>
	#include <linux/bits.h>
	#include <linux/err.h>
	#include <linux/hwmon.h>
	#include <linux/hwmon-sysfs.h>
	#include <linux/i2c.h>
	#include <linux/regmap.h>
	#include <linux/util_macros.h>

	#define REG_CR1 0x00
	#define CR1_HYST BIT(5)
	#define CR1_DRV GENMASK(4, 3)
	#define CR1_TEMP_SRC GENMASK(1, 0)
	#define REG_CR2 0x01
	#define CR2_STBY BIT(7)
	#define CR2_ALERTS BIT(6)
	#define CR2_DFC BIT(0)
	#define REG_CR3 0x02
	#define REG_PWMR 0x50
	#define REG_PWMV 0x51
	#define REG_STATUS 0x5A
	#define STATUS_ALARM_CRIT(ch) BIT(2 + 2 * (ch))
	#define STATUS_ALARM_MAX(ch) BIT(3 + 2 * (ch))
	#define STATUS_RDFA BIT(6)

	#define REG_TACH(ch) (0x52 + (ch) * 2)
	#define REG_TEMP_INPUT(ch) (0x56 + (ch) * 2)
	#define REG_TEMP_MAX(ch) (0x06 + (ch) * 2)
	#define REG_TEMP_CRIT(ch) (0x0A + (ch) * 2)

	#define TEMP11_FROM_REG(reg) ((reg) / 32 * 125)
	#define TEMP11_TO_REG(val) (DIV_ROUND_CLOSEST(clamp_val((val), -128000, \
	127875), 125) * 32)

	#define LUT_SIZE 48

	#define REG_LUT(index) (0x20 + (index))

	struct max31760_state {
	struct regmap *regmap;

	struct lut_attribute {
	char name[24];
	struct sensor_device_attribute sda;
	} lut[LUT_SIZE];

	struct attribute *attrs[LUT_SIZE + 2];
	struct attribute_group group;
	const struct attribute_group *groups[2];
	};

	static bool max31760_volatile_reg(struct device *dev, unsigned int reg)
	{
	return reg > 0x50;
	}

	static const struct regmap_config regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0x5B,
	.cache_type = REGCACHE_RBTREE,
	.volatile_reg = max31760_volatile_reg,
	};

	static const int max31760_pwm_freq[] = {33, 150, 1500, 25000};

	static int tach_to_rpm(u16 tach)
	{
	if (tach == 0)
	tach = 1;

	return 60 * 100000 / tach / 2;
	}

	static int max31760_read(struct device *dev, enum hwmon_sensor_types type,
	u32 attr, int channel, long *val)
	{
	struct max31760_state *state = dev_get_drvdata(dev);
	unsigned int regval;
	unsigned int reg_temp;
	s16 temp;
	u8 reg[2];
	int ret;

	switch (type) {
	case hwmon_temp:
	switch (attr) {
	case hwmon_temp_fault:
	ret = regmap_read(state->regmap, REG_STATUS, &regval);
	if (ret)
	return ret;

	*val = FIELD_GET(STATUS_RDFA, regval);

	return 0;
	case hwmon_temp_max_alarm:
	ret = regmap_read(state->regmap, REG_STATUS, &regval);
	if (ret)
	return ret;

	if (channel)
	*val = FIELD_GET(STATUS_ALARM_MAX(1), regval);
	else
	*val = FIELD_GET(STATUS_ALARM_MAX(0), regval);

	return 0;
	case hwmon_temp_crit_alarm:
	ret = regmap_read(state->regmap, REG_STATUS, &regval);
	if (ret)
	return ret;

	if (channel)
	*val = FIELD_GET(STATUS_ALARM_CRIT(1), regval);
	else
	*val = FIELD_GET(STATUS_ALARM_CRIT(0), regval);

	return 0;
	case hwmon_temp_input:
	reg_temp = REG_TEMP_INPUT(channel);
	break;
	case hwmon_temp_max:
	reg_temp = REG_TEMP_MAX(channel);
	break;
	case hwmon_temp_crit:
	reg_temp = REG_TEMP_CRIT(channel);
	break;
	default:
	return -EOPNOTSUPP;
	}

	ret = regmap_bulk_read(state->regmap, reg_temp, reg, 2);
	if (ret)
	return ret;

	temp = (reg[0] << 8) \| reg[1];

	*val = TEMP11_FROM_REG(temp);

	return 0;
	case hwmon_fan:
	switch (attr) {
	case hwmon_fan_input:
	ret = regmap_bulk_read(state->regmap, REG_TACH(channel), reg, 2);
	if (ret)
	return ret;

	val = tach_to_rpm(reg[0] 256 + reg[1]);

	return 0;
	case hwmon_fan_fault:
	ret = regmap_read(state->regmap, REG_STATUS, &regval);
	if (ret)
	return ret;

	if (channel)
	*val = FIELD_GET(BIT(1), regval);
	else
	*val = FIELD_GET(BIT(0), regval);

	return 0;
	case hwmon_fan_enable:
	ret = regmap_read(state->regmap, REG_CR3, &regval);
	if (ret)
	return ret;

	if (channel)
	*val = FIELD_GET(BIT(1), regval);
	else
	*val = FIELD_GET(BIT(0), regval);

	return 0;
	default:
	return -EOPNOTSUPP;
	}
	case hwmon_pwm:
	switch (attr) {
	case hwmon_pwm_input:
	ret = regmap_read(state->regmap, REG_PWMV, &regval);
	if (ret)
	return ret;

	*val = regval;

	return 0;
	case hwmon_pwm_freq:
	ret = regmap_read(state->regmap, REG_CR1, &regval);
	if (ret)
	return ret;

	regval = FIELD_GET(CR1_DRV, regval);
	if (regval >= ARRAY_SIZE(max31760_pwm_freq))
	return -EINVAL;

	*val = max31760_pwm_freq[regval];

	return 0;
	case hwmon_pwm_enable:
	ret = regmap_read(state->regmap, REG_CR2, &regval);
	if (ret)
	return ret;

	*val = 2 - FIELD_GET(CR2_DFC, regval);

	return 0;
	case hwmon_pwm_auto_channels_temp:
	ret = regmap_read(state->regmap, REG_CR1, &regval);
	if (ret)
	return ret;

	switch (FIELD_GET(CR1_TEMP_SRC, regval)) {
	case 0:
	*val = 2;
	break;
	case 1:
	*val = 1;
	break;
	case 2:
	case 3:
	*val = 3;
	break;
	default:
	return -EINVAL;
	}

	return 0;
	default:
	return -EOPNOTSUPP;
	}
	default:
	return -EOPNOTSUPP;
	}
	}

	static int max31760_write(struct device *dev, enum hwmon_sensor_types type,
	u32 attr, int channel, long val)
	{
	struct max31760_state *state = dev_get_drvdata(dev);
	unsigned int pwm_index;
	unsigned int reg_temp;
	int temp;
	u8 reg_val[2];

	switch (type) {
	case hwmon_temp:
	switch (attr) {
	case hwmon_temp_max:
	reg_temp = REG_TEMP_MAX(channel);
	break;
	case hwmon_temp_crit:
	reg_temp = REG_TEMP_CRIT(channel);
	break;
	default:
	return -EOPNOTSUPP;
	}

	temp = TEMP11_TO_REG(val);
	reg_val[0] = temp >> 8;
	reg_val[1] = temp & 0xFF;

	return regmap_bulk_write(state->regmap, reg_temp, reg_val, 2);
	case hwmon_fan:
	switch (attr) {
	case hwmon_fan_enable:
	if (val == 0)
	return regmap_clear_bits(state->regmap, REG_CR3, BIT(channel));

	if (val == 1)
	return regmap_set_bits(state->regmap, REG_CR3, BIT(channel));

	return -EINVAL;
	default:
	return -EOPNOTSUPP;
	}
	case hwmon_pwm:
	switch (attr) {
	case hwmon_pwm_input:
	if (val < 0 \|\| val > 255)
	return -EINVAL;

	return regmap_write(state->regmap, REG_PWMR, val);
	case hwmon_pwm_enable:
	if (val == 1)
	return regmap_set_bits(state->regmap, REG_CR2, CR2_DFC);

	if (val == 2)
	return regmap_clear_bits(state->regmap, REG_CR2, CR2_DFC);

	return -EINVAL;
	case hwmon_pwm_freq:
	pwm_index = find_closest(val, max31760_pwm_freq,
	ARRAY_SIZE(max31760_pwm_freq));

	return regmap_update_bits(state->regmap,
	REG_CR1, CR1_DRV,
	FIELD_PREP(CR1_DRV, pwm_index));
	case hwmon_pwm_auto_channels_temp:
	switch (val) {
	case 1:
	break;
	case 2:
	val = 0;
	break;
	case 3:
	val = 2;
	break;
	default:
	return -EINVAL;
	}

	return regmap_update_bits(state->regmap, REG_CR1, CR1_TEMP_SRC, val);
	default:
	return -EOPNOTSUPP;
	}
	default:
	return -EOPNOTSUPP;
	}
	}

	static const struct hwmon_channel_info * const max31760_info[] = {
	HWMON_CHANNEL_INFO(chip,
	HWMON_C_REGISTER_TZ),
	HWMON_CHANNEL_INFO(fan,
	HWMON_F_INPUT \| HWMON_F_FAULT \| HWMON_F_ENABLE,
	HWMON_F_INPUT \| HWMON_F_FAULT \| HWMON_F_ENABLE),
	HWMON_CHANNEL_INFO(temp,
	HWMON_T_INPUT \| HWMON_T_MAX \| HWMON_T_CRIT \| HWMON_T_FAULT \|
	HWMON_T_MAX_ALARM \| HWMON_T_CRIT_ALARM \| HWMON_T_LABEL,
	HWMON_T_INPUT \| HWMON_T_MAX \| HWMON_T_CRIT \|
	HWMON_T_MAX_ALARM \| HWMON_T_CRIT_ALARM \| HWMON_T_LABEL),
	HWMON_CHANNEL_INFO(pwm,
	HWMON_PWM_ENABLE \| HWMON_PWM_FREQ \| HWMON_PWM_INPUT \|
	HWMON_PWM_AUTO_CHANNELS_TEMP),
	NULL
	};

	static umode_t max31760_is_visible(const void *data,
	enum hwmon_sensor_types type,
	u32 attr, int channel)
	{
	switch (type) {
	case hwmon_temp:
	switch (attr) {
	case hwmon_temp_input:
	case hwmon_temp_max_alarm:
	case hwmon_temp_crit_alarm:
	case hwmon_temp_fault:
	case hwmon_temp_label:
	return 0444;
	case hwmon_temp_max:
	case hwmon_temp_crit:
	return 0644;
	default:
	return 0;
	}
	case hwmon_fan:
	switch (attr) {
	case hwmon_fan_input:
	case hwmon_fan_fault:
	return 0444;
	case hwmon_fan_enable:
	return 0644;
	default:
	return 0;
	}
	case hwmon_pwm:
	switch (attr) {
	case hwmon_pwm_enable:
	case hwmon_pwm_input:
	case hwmon_pwm_freq:
	case hwmon_pwm_auto_channels_temp:
	return 0644;
	default:
	return 0;
	}
	default:
	return 0;
	}
	}

	static int max31760_read_string(struct device *dev,
	enum hwmon_sensor_types type,
	u32 attr, int channel, const char **str)
	{
	switch (type) {
	case hwmon_temp:
	if (attr != hwmon_temp_label)
	return -EOPNOTSUPP;

	*str = channel ? "local" : "remote";

	return 0;
	default:
	return -EOPNOTSUPP;
	}
	}

	static const struct hwmon_ops max31760_hwmon_ops = {
	.is_visible = max31760_is_visible,
	.read = max31760_read,
	.write = max31760_write,
	.read_string = max31760_read_string
	};

	static const struct hwmon_chip_info max31760_chip_info = {
	.ops = &max31760_hwmon_ops,
	.info = max31760_info,
	};

	static ssize_t lut_show(struct device *dev,
	struct device_attribute devattr, char buf)
	{
	struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
	struct max31760_state *state = dev_get_drvdata(dev);
	int ret;
	unsigned int regval;

	ret = regmap_read(state->regmap, REG_LUT(sda->index), &regval);
	if (ret)
	return ret;

	return sysfs_emit(buf, "%d\n", regval);
	}

	static ssize_t lut_store(struct device *dev,
	struct device_attribute *devattr,
	const char *buf, size_t count)
	{
	struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
	struct max31760_state *state = dev_get_drvdata(dev);
	int ret;
	u8 pwm;

	ret = kstrtou8(buf, 10, &pwm);
	if (ret)
	return ret;

	ret = regmap_write(state->regmap, REG_LUT(sda->index), pwm);
	if (ret)
	return ret;

	return count;
	}

	static ssize_t pwm1_auto_point_temp_hyst_show(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct max31760_state *state = dev_get_drvdata(dev);
	unsigned int regval;
	int ret;

	ret = regmap_read(state->regmap, REG_CR1, &regval);
	if (ret)
	return ret;

	return sysfs_emit(buf, "%d\n", (1 + (int)FIELD_GET(CR1_HYST, regval)) * 2000);
	}

	static ssize_t pwm1_auto_point_temp_hyst_store(struct device *dev,
	struct device_attribute *attr,
	const char *buf,
	size_t count)
	{
	struct max31760_state *state = dev_get_drvdata(dev);
	unsigned int hyst;
	int ret;

	ret = kstrtou32(buf, 10, &hyst);
	if (ret)
	return ret;

	if (hyst < 3000)
	ret = regmap_clear_bits(state->regmap, REG_CR1, CR1_HYST);
	else
	ret = regmap_set_bits(state->regmap, REG_CR1, CR1_HYST);

	if (ret)
	return ret;

	return count;
	}

	static DEVICE_ATTR_RW(pwm1_auto_point_temp_hyst);

	static void max31760_create_lut_nodes(struct max31760_state *state)
	{
	int i;
	struct sensor_device_attribute *sda;
	struct lut_attribute *lut;

	for (i = 0; i < LUT_SIZE; ++i) {
	lut = &state->lut[i];
	sda = &lut->sda;

	snprintf(lut->name, sizeof(lut->name),
	"pwm1_auto_point%d_pwm", i + 1);

	sda->dev_attr.attr.mode = 0644;
	sda->index = i;
	sda->dev_attr.show = lut_show;
	sda->dev_attr.store = lut_store;
	sda->dev_attr.attr.name = lut->name;

	sysfs_attr_init(&sda->dev_attr.attr);

	state->attrs[i] = &sda->dev_attr.attr;
	}

	state->attrs[i] = &dev_attr_pwm1_auto_point_temp_hyst.attr;

	state->group.attrs = state->attrs;
	state->groups[0] = &state->group;
	}

	static int max31760_probe(struct i2c_client *client)
	{
	struct device *dev = &client->dev;
	struct max31760_state *state;
	struct device *hwmon_dev;
	int ret;

	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
	if (!state)
	return -ENOMEM;

	state->regmap = devm_regmap_init_i2c(client, &regmap_config);
	if (IS_ERR(state->regmap))
	return dev_err_probe(dev,
	PTR_ERR(state->regmap),
	"regmap initialization failed\n");

	dev_set_drvdata(dev, state);

	/* Set alert output to comparator mode */
	ret = regmap_set_bits(state->regmap, REG_CR2, CR2_ALERTS);
	if (ret)
	return dev_err_probe(dev, ret, "cannot write register\n");

	max31760_create_lut_nodes(state);

	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
	state,
	&max31760_chip_info,
	state->groups);

	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static const struct of_device_id max31760_of_match[] = {
	{.compatible = "adi,max31760"},
	{ }
	};
	MODULE_DEVICE_TABLE(of, max31760_of_match);

	static const struct i2c_device_id max31760_id[] = {
	{"max31760"},
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, max31760_id);

	static int max31760_suspend(struct device *dev)
	{
	struct max31760_state *state = dev_get_drvdata(dev);

	return regmap_set_bits(state->regmap, REG_CR2, CR2_STBY);
	}

	static int max31760_resume(struct device *dev)
	{
	struct max31760_state *state = dev_get_drvdata(dev);

	return regmap_clear_bits(state->regmap, REG_CR2, CR2_STBY);
	}

	static DEFINE_SIMPLE_DEV_PM_OPS(max31760_pm_ops, max31760_suspend,
	max31760_resume);

	static struct i2c_driver max31760_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
	.name = "max31760",
	.of_match_table = max31760_of_match,
	.pm = pm_ptr(&max31760_pm_ops)
	},
	.probe = max31760_probe,
	.id_table = max31760_id
	};
	module_i2c_driver(max31760_driver);

	MODULE_AUTHOR("Ibrahim Tilki <Ibrahim.Tilki@analog.com>");
	MODULE_DESCRIPTION("Analog Devices MAX31760 Fan Speed Controller");
	MODULE_SOFTDEP("pre: regmap_i2c");
	MODULE_VERSION("1.0");
	MODULE_LICENSE("GPL");