drivers/hwmon/adm9240.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * adm9240.c	Part of lm_sensors, Linux kernel modules for hardware
  *		monitoring
  *
  * Copyright (C) 1999	Frodo Looijaard <frodol@dds.nl>
  *			Philip Edelbrock <phil@netroedge.com>
  * Copyright (C) 2003	Michiel Rook <michiel@grendelproject.nl>
  * Copyright (C) 2005	Grant Coady <gcoady.lk@gmail.com> with valuable
  *				guidance from Jean Delvare
  *
  * Driver supports	Analog Devices		ADM9240
  *			Dallas Semiconductor	DS1780
  *			National Semiconductor	LM81
  *
  * ADM9240 is the reference, DS1780 and LM81 are register compatibles
  *
  * Voltage	Six inputs are scaled by chip, VID also reported
  * Temperature	Chip temperature to 0.5'C, maximum and max_hysteris
  * Fans		2 fans, low speed alarm, automatic fan clock divider
  * Alarms	16-bit map of active alarms
  * Analog Out	0..1250 mV output
  *
  * Chassis Intrusion: clear CI latch with 'echo 0 > intrusion0_alarm'
  *
  * Test hardware: Intel SE440BX-2 desktop motherboard --Grant
  *
  * LM81 extended temp reading not implemented
  */

 #include <linux/bits.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-vid.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/regmap.h>

 /* Addresses to scan */
 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
 					I2C_CLIENT_END };

 enum chips { adm9240, ds1780, lm81 };

 /* ADM9240 registers */
 #define ADM9240_REG_MAN_ID		0x3e
 #define ADM9240_REG_DIE_REV		0x3f
 #define ADM9240_REG_CONFIG		0x40

 #define ADM9240_REG_IN(nr)		(0x20 + (nr))   /* 0..5 */
 #define ADM9240_REG_IN_MAX(nr)		(0x2b + (nr) * 2)
 #define ADM9240_REG_IN_MIN(nr)		(0x2c + (nr) * 2)
 #define ADM9240_REG_FAN(nr)		(0x28 + (nr))   /* 0..1 */
 #define ADM9240_REG_FAN_MIN(nr)		(0x3b + (nr))
 #define ADM9240_REG_INT(nr)		(0x41 + (nr))
 #define ADM9240_REG_INT_MASK(nr)	(0x43 + (nr))
 #define ADM9240_REG_TEMP		0x27
 #define ADM9240_REG_TEMP_MAX(nr)	(0x39 + (nr)) /* 0, 1 = high, hyst */
 #define ADM9240_REG_ANALOG_OUT		0x19
 #define ADM9240_REG_CHASSIS_CLEAR	0x46
 #define ADM9240_REG_VID_FAN_DIV		0x47
 #define ADM9240_REG_I2C_ADDR		0x48
 #define ADM9240_REG_VID4		0x49
 #define ADM9240_REG_TEMP_CONF		0x4b

 /* generalised scaling with integer rounding */
 static inline int SCALE(long val, int mul, int div)
 {
 	if (val < 0)
 		return (val * mul - div / 2) / div;
 	else
 		return (val * mul + div / 2) / div;
 }

 /* adm9240 internally scales voltage measurements */
 static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };

 static inline unsigned int IN_FROM_REG(u8 reg, int n)
 {
 	return SCALE(reg, nom_mv[n], 192);
 }

 static inline u8 IN_TO_REG(unsigned long val, int n)
 {
 	val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
 	return SCALE(val, 192, nom_mv[n]);
 }

 /* temperature range: -40..125, 127 disables temperature alarm */
 static inline s8 TEMP_TO_REG(long val)
 {
 	val = clamp_val(val, -40000, 127000);
 	return SCALE(val, 1, 1000);
 }

 /* two fans, each with low fan speed limit */
 static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
 {
 	if (!reg) /* error */
 		return -1;

 	if (reg == 255)
 		return 0;

 	return SCALE(1350000, 1, reg * div);
 }

 /* analog out 0..1250mV */
 static inline u8 AOUT_TO_REG(unsigned long val)
 {
 	val = clamp_val(val, 0, 1250);
 	return SCALE(val, 255, 1250);
 }

 static inline unsigned int AOUT_FROM_REG(u8 reg)
 {
 	return SCALE(reg, 1250, 255);
 }

 /* per client data */
 struct adm9240_data {
 	struct device *dev;
 	struct regmap *regmap;
 	struct mutex update_lock;

 	u8 fan_div[2];		/* rw	fan1_div, read-only accessor */
 	u8 vrm;			/* --	vrm set on startup, no accessor */
 };

 /* write new fan div, callers must hold data->update_lock */
 static int adm9240_write_fan_div(struct adm9240_data *data, int channel, u8 fan_div)
 {
 	unsigned int reg, old, shift = (channel + 2) * 2;
 	int err;

 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &reg);
 	if (err < 0)
 		return err;
 	old = (reg >> shift) & 3;
 	reg &= ~(3 << shift);
 	reg |= (fan_div << shift);
 	err = regmap_write(data->regmap, ADM9240_REG_VID_FAN_DIV, reg);
 	if (err < 0)
 		return err;
 	dev_dbg(data->dev,
 		"fan%d clock divider changed from %lu to %lu\n",
 		channel + 1, BIT(old), BIT(fan_div));

 	return 0;
 }

 /*
  * set fan speed low limit:
  *
  * - value is zero: disable fan speed low limit alarm
  *
  * - value is below fan speed measurement range: enable fan speed low
  *   limit alarm to be asserted while fan speed too slow to measure
  *
  * - otherwise: select fan clock divider to suit fan speed low limit,
  *   measurement code may adjust registers to ensure fan speed reading
  */
 static int adm9240_fan_min_write(struct adm9240_data *data, int channel, long val)
 {
 	u8 new_div;
 	u8 fan_min;
 	int err;

 	mutex_lock(&data->update_lock);

 	if (!val) {
 		fan_min = 255;
 		new_div = data->fan_div[channel];

 		dev_dbg(data->dev, "fan%u low limit set disabled\n", channel + 1);
 	} else if (val < 1350000 / (8 * 254)) {
 		new_div = 3;
 		fan_min = 254;

 		dev_dbg(data->dev, "fan%u low limit set minimum %u\n",
 			channel + 1, FAN_FROM_REG(254, BIT(new_div)));
 	} else {
 		unsigned int new_min = 1350000 / val;

 		new_div = 0;
 		while (new_min > 192 && new_div < 3) {
 			new_div++;
 			new_min /= 2;
 		}
 		if (!new_min) /* keep > 0 */
 			new_min++;

 		fan_min = new_min;

 		dev_dbg(data->dev, "fan%u low limit set fan speed %u\n",
 			channel + 1, FAN_FROM_REG(new_min, BIT(new_div)));
 	}

 	if (new_div != data->fan_div[channel]) {
 		data->fan_div[channel] = new_div;
 		adm9240_write_fan_div(data, channel, new_div);
 	}
 	err = regmap_write(data->regmap, ADM9240_REG_FAN_MIN(channel), fan_min);

 	mutex_unlock(&data->update_lock);

 	return err;
 }

 static ssize_t cpu0_vid_show(struct device *dev,
 			     struct device_attribute *attr, char *buf)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int err;
 	u8 vid;

 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
 	if (err < 0)
 		return err;
 	vid = regval & 0x0f;
 	err = regmap_read(data->regmap, ADM9240_REG_VID4, &regval);
 	if (err < 0)
 		return err;
 	vid |= (regval & 1) << 4;
 	return sprintf(buf, "%d\n", vid_from_reg(vid, data->vrm));
 }
 static DEVICE_ATTR_RO(cpu0_vid);

 static ssize_t aout_output_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int err;

 	err = regmap_read(data->regmap, ADM9240_REG_ANALOG_OUT, &regval);
 	if (err)
 		return err;

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

 static ssize_t aout_output_store(struct device *dev,
 				 struct device_attribute *attr,
 				 const char *buf, size_t count)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	long val;
 	int err;

 	err = kstrtol(buf, 10, &val);
 	if (err)
 		return err;

 	err = regmap_write(data->regmap, ADM9240_REG_ANALOG_OUT, AOUT_TO_REG(val));
 	return err < 0 ? err : count;
 }
 static DEVICE_ATTR_RW(aout_output);

 static struct attribute *adm9240_attrs[] = {
 	&dev_attr_aout_output.attr,
 	&dev_attr_cpu0_vid.attr,
 	NULL
 };

 ATTRIBUTE_GROUPS(adm9240);

 /*** sensor chip detect and driver install ***/

 /* Return 0 if detection is successful, -ENODEV otherwise */
 static int adm9240_detect(struct i2c_client *new_client,
 			  struct i2c_board_info *info)
 {
 	struct i2c_adapter *adapter = new_client->adapter;
 	const char *name = "";
 	int address = new_client->addr;
 	u8 man_id, die_rev;

 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 		return -ENODEV;

 	/* verify chip: reg address should match i2c address */
 	if (i2c_smbus_read_byte_data(new_client, ADM9240_REG_I2C_ADDR) != address)
 		return -ENODEV;

 	/* check known chip manufacturer */
 	man_id = i2c_smbus_read_byte_data(new_client, ADM9240_REG_MAN_ID);
 	if (man_id == 0x23)
 		name = "adm9240";
 	else if (man_id == 0xda)
 		name = "ds1780";
 	else if (man_id == 0x01)
 		name = "lm81";
 	else
 		return -ENODEV;

 	/* successful detect, print chip info */
 	die_rev = i2c_smbus_read_byte_data(new_client, ADM9240_REG_DIE_REV);
 	dev_info(&adapter->dev, "found %s revision %u\n",
 		 man_id == 0x23 ? "ADM9240" :
 		 man_id == 0xda ? "DS1780" : "LM81", die_rev);

 	strscpy(info->type, name, I2C_NAME_SIZE);

 	return 0;
 }

 static int adm9240_init_client(struct adm9240_data *data)
 {
 	unsigned int regval;
 	u8 conf, mode;
 	int err;

 	err = regmap_raw_read(data->regmap, ADM9240_REG_CONFIG, &conf, 1);
 	if (err < 0)
 		return err;
 	err = regmap_raw_read(data->regmap, ADM9240_REG_TEMP_CONF, &mode, 1);
 	if (err < 0)
 		return err;
 	mode &= 3;

 	data->vrm = vid_which_vrm(); /* need this to report vid as mV */

 	dev_info(data->dev, "Using VRM: %d.%d\n", data->vrm / 10,
 		 data->vrm % 10);

 	if (conf & 1) { /* measurement cycle running: report state */

 		dev_info(data->dev, "status: config 0x%02x mode %u\n",
 			 conf, mode);

 	} else { /* cold start: open limits before starting chip */
 		int i;

 		for (i = 0; i < 6; i++) {
 			err = regmap_write(data->regmap,
 					   ADM9240_REG_IN_MIN(i), 0);
 			if (err < 0)
 				return err;
 			err = regmap_write(data->regmap,
 					   ADM9240_REG_IN_MAX(i), 255);
 			if (err < 0)
 				return err;
 		}
 		for (i = 0; i < 2; i++) {
 			err = regmap_write(data->regmap,
 					   ADM9240_REG_FAN_MIN(i), 255);
 			if (err < 0)
 				return err;
 		}
 		for (i = 0; i < 2; i++) {
 			err = regmap_write(data->regmap,
 					   ADM9240_REG_TEMP_MAX(i), 127);
 			if (err < 0)
 				return err;
 		}

 		/* start measurement cycle */
 		err = regmap_write(data->regmap, ADM9240_REG_CONFIG, 1);
 		if (err < 0)
 			return err;

 		dev_info(data->dev,
 			 "cold start: config was 0x%02x mode %u\n", conf, mode);
 	}

 	/* read fan divs */
 	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
 	if (err < 0)
 		return err;
 	data->fan_div[0] = (regval >> 4) & 3;
 	data->fan_div[1] = (regval >> 6) & 3;
 	return 0;
 }

 static int adm9240_chip_read(struct device *dev, u32 attr, long *val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	u8 regs[2];
 	int err;

 	switch (attr) {
 	case hwmon_chip_alarms:
 		err = regmap_bulk_read(data->regmap, ADM9240_REG_INT(0), &regs, 2);
 		if (err < 0)
 			return err;
 		*val = regs[0] | regs[1] << 8;
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_intrusion_read(struct device *dev, u32 attr, long *val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int err;

 	switch (attr) {
 	case hwmon_intrusion_alarm:
 		err = regmap_read(data->regmap, ADM9240_REG_INT(1), &regval);
 		if (err < 0)
 			return err;
 		*val = !!(regval & BIT(4));
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_intrusion_write(struct device *dev, u32 attr, long val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	int err;

 	switch (attr) {
 	case hwmon_intrusion_alarm:
 		if (val)
 			return -EINVAL;
 		err = regmap_write(data->regmap, ADM9240_REG_CHASSIS_CLEAR, 0x80);
 		if (err < 0)
 			return err;
 		dev_dbg(data->dev, "chassis intrusion latch cleared\n");
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_in_read(struct device *dev, u32 attr, int channel, long *val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int reg;
 	int err;

 	switch (attr) {
 	case hwmon_in_input:
 		reg = ADM9240_REG_IN(channel);
 		break;
 	case hwmon_in_min:
 		reg = ADM9240_REG_IN_MIN(channel);
 		break;
 	case hwmon_in_max:
 		reg = ADM9240_REG_IN_MAX(channel);
 		break;
 	case hwmon_in_alarm:
 		if (channel < 4) {
 			reg = ADM9240_REG_INT(0);
 		} else {
 			reg = ADM9240_REG_INT(1);
 			channel -= 4;
 		}
 		err = regmap_read(data->regmap, reg, &regval);
 		if (err < 0)
 			return err;
 		*val = !!(regval & BIT(channel));
 		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
 	err = regmap_read(data->regmap, reg, &regval);
 	if (err < 0)
 		return err;
 	*val = IN_FROM_REG(regval, channel);
 	return 0;
 }

 static int adm9240_in_write(struct device *dev, u32 attr, int channel, long val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	int reg;

 	switch (attr) {
 	case hwmon_in_min:
 		reg = ADM9240_REG_IN_MIN(channel);
 		break;
 	case hwmon_in_max:
 		reg = ADM9240_REG_IN_MAX(channel);
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return regmap_write(data->regmap, reg, IN_TO_REG(val, channel));
 }

 static int adm9240_fan_read(struct device *dev, u32 attr, int channel, long *val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int err;

 	switch (attr) {
 	case hwmon_fan_input:
 		mutex_lock(&data->update_lock);
 		err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), &regval);
 		if (err < 0) {
 			mutex_unlock(&data->update_lock);
 			return err;
 		}
 		if (regval == 255 && data->fan_div[channel] < 3) {
 			/* adjust fan clock divider on overflow */
 			err = adm9240_write_fan_div(data, channel,
 						    ++data->fan_div[channel]);
 			if (err) {
 				mutex_unlock(&data->update_lock);
 				return err;
 			}
 		}
 		*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
 		mutex_unlock(&data->update_lock);
 		break;
 	case hwmon_fan_div:
 		*val = BIT(data->fan_div[channel]);
 		break;
 	case hwmon_fan_min:
 		err = regmap_read(data->regmap, ADM9240_REG_FAN_MIN(channel), &regval);
 		if (err < 0)
 			return err;
 		*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
 		break;
 	case hwmon_fan_alarm:
 		err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
 		if (err < 0)
 			return err;
 		*val = !!(regval & BIT(channel + 6));
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_fan_write(struct device *dev, u32 attr, int channel, long val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	int err;

 	switch (attr) {
 	case hwmon_fan_min:
 		err = adm9240_fan_min_write(data, channel, val);
 		if (err < 0)
 			return err;
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_temp_read(struct device *dev, u32 attr, int channel, long *val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	unsigned int regval;
 	int err, temp;

 	switch (attr) {
 	case hwmon_temp_input:
 		err = regmap_read(data->regmap, ADM9240_REG_TEMP, &regval);
 		if (err < 0)
 			return err;
 		temp = regval << 1;
 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_CONF, &regval);
 		if (err < 0)
 			return err;
 		temp |= regval >> 7;
 		*val = sign_extend32(temp, 8) * 500;
 		break;
 	case hwmon_temp_max:
 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(0), &regval);
 		if (err < 0)
 			return err;
 		*val = (s8)regval * 1000;
 		break;
 	case hwmon_temp_max_hyst:
 		err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(1), &regval);
 		if (err < 0)
 			return err;
 		*val = (s8)regval * 1000;
 		break;
 	case hwmon_temp_alarm:
 		err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
 		if (err < 0)
 			return err;
 		*val = !!(regval & BIT(4));
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return 0;
 }

 static int adm9240_temp_write(struct device *dev, u32 attr, int channel, long val)
 {
 	struct adm9240_data *data = dev_get_drvdata(dev);
 	int reg;

 	switch (attr) {
 	case hwmon_temp_max:
 		reg = ADM9240_REG_TEMP_MAX(0);
 		break;
 	case hwmon_temp_max_hyst:
 		reg = ADM9240_REG_TEMP_MAX(1);
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}
 	return regmap_write(data->regmap, reg, TEMP_TO_REG(val));
 }

 static int adm9240_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 			int channel, long *val)
 {
 	switch (type) {
 	case hwmon_chip:
 		return adm9240_chip_read(dev, attr, val);
 	case hwmon_intrusion:
 		return adm9240_intrusion_read(dev, attr, val);
 	case hwmon_in:
 		return adm9240_in_read(dev, attr, channel, val);
 	case hwmon_fan:
 		return adm9240_fan_read(dev, attr, channel, val);
 	case hwmon_temp:
 		return adm9240_temp_read(dev, attr, channel, val);
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static int adm9240_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 			 int channel, long val)
 {
 	switch (type) {
 	case hwmon_intrusion:
 		return adm9240_intrusion_write(dev, attr, val);
 	case hwmon_in:
 		return adm9240_in_write(dev, attr, channel, val);
 	case hwmon_fan:
 		return adm9240_fan_write(dev, attr, channel, val);
 	case hwmon_temp:
 		return adm9240_temp_write(dev, attr, channel, val);
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static umode_t adm9240_is_visible(const void *_data, enum hwmon_sensor_types type,
 				  u32 attr, int channel)
 {
 	umode_t mode = 0;

 	switch (type) {
 	case hwmon_chip:
 		switch (attr) {
 		case hwmon_chip_alarms:
 			mode = 0444;
 			break;
 		default:
 			break;
 		}
 		break;
 	case hwmon_intrusion:
 		switch (attr) {
 		case hwmon_intrusion_alarm:
 			mode = 0644;
 			break;
 		default:
 			break;
 		}
 		break;
 	case hwmon_temp:
 		switch (attr) {
 		case hwmon_temp:
 		case hwmon_temp_alarm:
 			mode = 0444;
 			break;
 		case hwmon_temp_max:
 		case hwmon_temp_max_hyst:
 			mode = 0644;
 			break;
 		default:
 			break;
 		}
 		break;
 	case hwmon_fan:
 		switch (attr) {
 		case hwmon_fan_input:
 		case hwmon_fan_div:
 		case hwmon_fan_alarm:
 			mode = 0444;
 			break;
 		case hwmon_fan_min:
 			mode = 0644;
 			break;
 		default:
 			break;
 		}
 		break;
 	case hwmon_in:
 		switch (attr) {
 		case hwmon_in_input:
 		case hwmon_in_alarm:
 			mode = 0444;
 			break;
 		case hwmon_in_min:
 		case hwmon_in_max:
 			mode = 0644;
 			break;
 		default:
 			break;
 		}
 		break;
 	default:
 		break;
 	}
 	return mode;
 }

 static const struct hwmon_ops adm9240_hwmon_ops = {
 	.is_visible = adm9240_is_visible,
 	.read = adm9240_read,
 	.write = adm9240_write,
 };

 static const struct hwmon_channel_info *adm9240_info[] = {
 	HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS),
 	HWMON_CHANNEL_INFO(intrusion, HWMON_INTRUSION_ALARM),
 	HWMON_CHANNEL_INFO(temp,
 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_ALARM),
 	HWMON_CHANNEL_INFO(in,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM),
 	HWMON_CHANNEL_INFO(fan,
 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM,
 			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_DIV | HWMON_F_ALARM),
 	NULL
 };

 static const struct hwmon_chip_info adm9240_chip_info = {
 	.ops = &adm9240_hwmon_ops,
 	.info = adm9240_info,
 };

 static bool adm9240_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case ADM9240_REG_IN(0) ... ADM9240_REG_IN(5):
 	case ADM9240_REG_FAN(0) ... ADM9240_REG_FAN(1):
 	case ADM9240_REG_INT(0) ... ADM9240_REG_INT(1):
 	case ADM9240_REG_TEMP:
 	case ADM9240_REG_TEMP_CONF:
 	case ADM9240_REG_VID_FAN_DIV:
 	case ADM9240_REG_VID4:
 	case ADM9240_REG_ANALOG_OUT:
 		return true;
 	default:
 		return false;
 	}
 }

 static const struct regmap_config adm9240_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.use_single_read = true,
 	.use_single_write = true,
 	.volatile_reg = adm9240_volatile_reg,
 };

 static int adm9240_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
 	struct device *hwmon_dev;
 	struct adm9240_data *data;
 	int err;

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

 	data->dev = dev;
 	mutex_init(&data->update_lock);
 	data->regmap = devm_regmap_init_i2c(client, &adm9240_regmap_config);
 	if (IS_ERR(data->regmap))
 		return PTR_ERR(data->regmap);

 	err = adm9240_init_client(data);
 	if (err < 0)
 		return err;

 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
 							 &adm9240_chip_info,
 							 adm9240_groups);
 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static const struct i2c_device_id adm9240_id[] = {
 	{ "adm9240", adm9240 },
 	{ "ds1780", ds1780 },
 	{ "lm81", lm81 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adm9240_id);

 static struct i2c_driver adm9240_driver = {
 	.class		= I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "adm9240",
 	},
 	.probe_new	= adm9240_probe,
 	.id_table	= adm9240_id,
 	.detect		= adm9240_detect,
 	.address_list	= normal_i2c,
 };

 module_i2c_driver(adm9240_driver);

 MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
 		"Grant Coady <gcoady.lk@gmail.com> and others");
 MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* adm9240.c Part of lm_sensors, Linux kernel modules for hardware
	* monitoring
	*
	* Copyright (C) 1999 Frodo Looijaard <frodol@dds.nl>
	* Philip Edelbrock <phil@netroedge.com>
	* Copyright (C) 2003 Michiel Rook <michiel@grendelproject.nl>
	* Copyright (C) 2005 Grant Coady <gcoady.lk@gmail.com> with valuable
	* guidance from Jean Delvare
	*
	* Driver supports Analog Devices ADM9240
	* Dallas Semiconductor DS1780
	* National Semiconductor LM81
	*
	* ADM9240 is the reference, DS1780 and LM81 are register compatibles
	*
	* Voltage Six inputs are scaled by chip, VID also reported
	* Temperature Chip temperature to 0.5'C, maximum and max_hysteris
	* Fans 2 fans, low speed alarm, automatic fan clock divider
	* Alarms 16-bit map of active alarms
	* Analog Out 0..1250 mV output
	*
	* Chassis Intrusion: clear CI latch with 'echo 0 > intrusion0_alarm'
	*
	* Test hardware: Intel SE440BX-2 desktop motherboard --Grant
	*
	* LM81 extended temp reading not implemented
	*/

	#include <linux/bits.h>
	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/i2c.h>
	#include <linux/hwmon-sysfs.h>
	#include <linux/hwmon.h>
	#include <linux/hwmon-vid.h>
	#include <linux/err.h>
	#include <linux/mutex.h>
	#include <linux/regmap.h>

	/* Addresses to scan */
	static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, 0x2f,
	I2C_CLIENT_END };

	enum chips { adm9240, ds1780, lm81 };

	/* ADM9240 registers */
	#define ADM9240_REG_MAN_ID 0x3e
	#define ADM9240_REG_DIE_REV 0x3f
	#define ADM9240_REG_CONFIG 0x40

	#define ADM9240_REG_IN(nr) (0x20 + (nr)) /* 0..5 */
	#define ADM9240_REG_IN_MAX(nr) (0x2b + (nr) * 2)
	#define ADM9240_REG_IN_MIN(nr) (0x2c + (nr) * 2)
	#define ADM9240_REG_FAN(nr) (0x28 + (nr)) /* 0..1 */
	#define ADM9240_REG_FAN_MIN(nr) (0x3b + (nr))
	#define ADM9240_REG_INT(nr) (0x41 + (nr))
	#define ADM9240_REG_INT_MASK(nr) (0x43 + (nr))
	#define ADM9240_REG_TEMP 0x27
	#define ADM9240_REG_TEMP_MAX(nr) (0x39 + (nr)) /* 0, 1 = high, hyst */
	#define ADM9240_REG_ANALOG_OUT 0x19
	#define ADM9240_REG_CHASSIS_CLEAR 0x46
	#define ADM9240_REG_VID_FAN_DIV 0x47
	#define ADM9240_REG_I2C_ADDR 0x48
	#define ADM9240_REG_VID4 0x49
	#define ADM9240_REG_TEMP_CONF 0x4b

	/* generalised scaling with integer rounding */
	static inline int SCALE(long val, int mul, int div)
	{
	if (val < 0)
	return (val * mul - div / 2) / div;
	else
	return (val * mul + div / 2) / div;
	}

	/* adm9240 internally scales voltage measurements */
	static const u16 nom_mv[] = { 2500, 2700, 3300, 5000, 12000, 2700 };

	static inline unsigned int IN_FROM_REG(u8 reg, int n)
	{
	return SCALE(reg, nom_mv[n], 192);
	}

	static inline u8 IN_TO_REG(unsigned long val, int n)
	{
	val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
	return SCALE(val, 192, nom_mv[n]);
	}

	/* temperature range: -40..125, 127 disables temperature alarm */
	static inline s8 TEMP_TO_REG(long val)
	{
	val = clamp_val(val, -40000, 127000);
	return SCALE(val, 1, 1000);
	}

	/* two fans, each with low fan speed limit */
	static inline unsigned int FAN_FROM_REG(u8 reg, u8 div)
	{
	if (!reg) /* error */
	return -1;

	if (reg == 255)
	return 0;

	return SCALE(1350000, 1, reg * div);
	}

	/* analog out 0..1250mV */
	static inline u8 AOUT_TO_REG(unsigned long val)
	{
	val = clamp_val(val, 0, 1250);
	return SCALE(val, 255, 1250);
	}

	static inline unsigned int AOUT_FROM_REG(u8 reg)
	{
	return SCALE(reg, 1250, 255);
	}

	/* per client data */
	struct adm9240_data {
	struct device *dev;
	struct regmap *regmap;
	struct mutex update_lock;

	u8 fan_div[2]; /* rw fan1_div, read-only accessor */
	u8 vrm; /* -- vrm set on startup, no accessor */
	};

	/* write new fan div, callers must hold data->update_lock */
	static int adm9240_write_fan_div(struct adm9240_data *data, int channel, u8 fan_div)
	{
	unsigned int reg, old, shift = (channel + 2) * 2;
	int err;

	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &reg);
	if (err < 0)
	return err;
	old = (reg >> shift) & 3;
	reg &= ~(3 << shift);
	reg \|= (fan_div << shift);
	err = regmap_write(data->regmap, ADM9240_REG_VID_FAN_DIV, reg);
	if (err < 0)
	return err;
	dev_dbg(data->dev,
	"fan%d clock divider changed from %lu to %lu\n",
	channel + 1, BIT(old), BIT(fan_div));

	return 0;
	}

	/*
	* set fan speed low limit:
	*
	* - value is zero: disable fan speed low limit alarm
	*
	* - value is below fan speed measurement range: enable fan speed low
	* limit alarm to be asserted while fan speed too slow to measure
	*
	* - otherwise: select fan clock divider to suit fan speed low limit,
	* measurement code may adjust registers to ensure fan speed reading
	*/
	static int adm9240_fan_min_write(struct adm9240_data *data, int channel, long val)
	{
	u8 new_div;
	u8 fan_min;
	int err;

	mutex_lock(&data->update_lock);

	if (!val) {
	fan_min = 255;
	new_div = data->fan_div[channel];

	dev_dbg(data->dev, "fan%u low limit set disabled\n", channel + 1);
	} else if (val < 1350000 / (8 * 254)) {
	new_div = 3;
	fan_min = 254;

	dev_dbg(data->dev, "fan%u low limit set minimum %u\n",
	channel + 1, FAN_FROM_REG(254, BIT(new_div)));
	} else {
	unsigned int new_min = 1350000 / val;

	new_div = 0;
	while (new_min > 192 && new_div < 3) {
	new_div++;
	new_min /= 2;
	}
	if (!new_min) /* keep > 0 */
	new_min++;

	fan_min = new_min;

	dev_dbg(data->dev, "fan%u low limit set fan speed %u\n",
	channel + 1, FAN_FROM_REG(new_min, BIT(new_div)));
	}

	if (new_div != data->fan_div[channel]) {
	data->fan_div[channel] = new_div;
	adm9240_write_fan_div(data, channel, new_div);
	}
	err = regmap_write(data->regmap, ADM9240_REG_FAN_MIN(channel), fan_min);

	mutex_unlock(&data->update_lock);

	return err;
	}

	static ssize_t cpu0_vid_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int err;
	u8 vid;

	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
	if (err < 0)
	return err;
	vid = regval & 0x0f;
	err = regmap_read(data->regmap, ADM9240_REG_VID4, &regval);
	if (err < 0)
	return err;
	vid \|= (regval & 1) << 4;
	return sprintf(buf, "%d\n", vid_from_reg(vid, data->vrm));
	}
	static DEVICE_ATTR_RO(cpu0_vid);

	static ssize_t aout_output_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int err;

	err = regmap_read(data->regmap, ADM9240_REG_ANALOG_OUT, &regval);
	if (err)
	return err;

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

	static ssize_t aout_output_store(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t count)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	long val;
	int err;

	err = kstrtol(buf, 10, &val);
	if (err)
	return err;

	err = regmap_write(data->regmap, ADM9240_REG_ANALOG_OUT, AOUT_TO_REG(val));
	return err < 0 ? err : count;
	}
	static DEVICE_ATTR_RW(aout_output);

	static struct attribute *adm9240_attrs[] = {
	&dev_attr_aout_output.attr,
	&dev_attr_cpu0_vid.attr,
	NULL
	};

	ATTRIBUTE_GROUPS(adm9240);

	/* sensor chip detect and driver install */

	/* Return 0 if detection is successful, -ENODEV otherwise */
	static int adm9240_detect(struct i2c_client *new_client,
	struct i2c_board_info *info)
	{
	struct i2c_adapter *adapter = new_client->adapter;
	const char *name = "";
	int address = new_client->addr;
	u8 man_id, die_rev;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
	return -ENODEV;

	/* verify chip: reg address should match i2c address */
	if (i2c_smbus_read_byte_data(new_client, ADM9240_REG_I2C_ADDR) != address)
	return -ENODEV;

	/* check known chip manufacturer */
	man_id = i2c_smbus_read_byte_data(new_client, ADM9240_REG_MAN_ID);
	if (man_id == 0x23)
	name = "adm9240";
	else if (man_id == 0xda)
	name = "ds1780";
	else if (man_id == 0x01)
	name = "lm81";
	else
	return -ENODEV;

	/* successful detect, print chip info */
	die_rev = i2c_smbus_read_byte_data(new_client, ADM9240_REG_DIE_REV);
	dev_info(&adapter->dev, "found %s revision %u\n",
	man_id == 0x23 ? "ADM9240" :
	man_id == 0xda ? "DS1780" : "LM81", die_rev);

	strscpy(info->type, name, I2C_NAME_SIZE);

	return 0;
	}

	static int adm9240_init_client(struct adm9240_data *data)
	{
	unsigned int regval;
	u8 conf, mode;
	int err;

	err = regmap_raw_read(data->regmap, ADM9240_REG_CONFIG, &conf, 1);
	if (err < 0)
	return err;
	err = regmap_raw_read(data->regmap, ADM9240_REG_TEMP_CONF, &mode, 1);
	if (err < 0)
	return err;
	mode &= 3;

	data->vrm = vid_which_vrm(); /* need this to report vid as mV */

	dev_info(data->dev, "Using VRM: %d.%d\n", data->vrm / 10,
	data->vrm % 10);

	if (conf & 1) { /* measurement cycle running: report state */

	dev_info(data->dev, "status: config 0x%02x mode %u\n",
	conf, mode);

	} else { /* cold start: open limits before starting chip */
	int i;

	for (i = 0; i < 6; i++) {
	err = regmap_write(data->regmap,
	ADM9240_REG_IN_MIN(i), 0);
	if (err < 0)
	return err;
	err = regmap_write(data->regmap,
	ADM9240_REG_IN_MAX(i), 255);
	if (err < 0)
	return err;
	}
	for (i = 0; i < 2; i++) {
	err = regmap_write(data->regmap,
	ADM9240_REG_FAN_MIN(i), 255);
	if (err < 0)
	return err;
	}
	for (i = 0; i < 2; i++) {
	err = regmap_write(data->regmap,
	ADM9240_REG_TEMP_MAX(i), 127);
	if (err < 0)
	return err;
	}

	/* start measurement cycle */
	err = regmap_write(data->regmap, ADM9240_REG_CONFIG, 1);
	if (err < 0)
	return err;

	dev_info(data->dev,
	"cold start: config was 0x%02x mode %u\n", conf, mode);
	}

	/* read fan divs */
	err = regmap_read(data->regmap, ADM9240_REG_VID_FAN_DIV, &regval);
	if (err < 0)
	return err;
	data->fan_div[0] = (regval >> 4) & 3;
	data->fan_div[1] = (regval >> 6) & 3;
	return 0;
	}

	static int adm9240_chip_read(struct device dev, u32 attr, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	u8 regs[2];
	int err;

	switch (attr) {
	case hwmon_chip_alarms:
	err = regmap_bulk_read(data->regmap, ADM9240_REG_INT(0), &regs, 2);
	if (err < 0)
	return err;
	*val = regs[0] \| regs[1] << 8;
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_intrusion_read(struct device dev, u32 attr, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int err;

	switch (attr) {
	case hwmon_intrusion_alarm:
	err = regmap_read(data->regmap, ADM9240_REG_INT(1), &regval);
	if (err < 0)
	return err;
	*val = !!(regval & BIT(4));
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_intrusion_write(struct device *dev, u32 attr, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	int err;

	switch (attr) {
	case hwmon_intrusion_alarm:
	if (val)
	return -EINVAL;
	err = regmap_write(data->regmap, ADM9240_REG_CHASSIS_CLEAR, 0x80);
	if (err < 0)
	return err;
	dev_dbg(data->dev, "chassis intrusion latch cleared\n");
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_in_read(struct device dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int reg;
	int err;

	switch (attr) {
	case hwmon_in_input:
	reg = ADM9240_REG_IN(channel);
	break;
	case hwmon_in_min:
	reg = ADM9240_REG_IN_MIN(channel);
	break;
	case hwmon_in_max:
	reg = ADM9240_REG_IN_MAX(channel);
	break;
	case hwmon_in_alarm:
	if (channel < 4) {
	reg = ADM9240_REG_INT(0);
	} else {
	reg = ADM9240_REG_INT(1);
	channel -= 4;
	}
	err = regmap_read(data->regmap, reg, &regval);
	if (err < 0)
	return err;
	*val = !!(regval & BIT(channel));
	return 0;
	default:
	return -EOPNOTSUPP;
	}
	err = regmap_read(data->regmap, reg, &regval);
	if (err < 0)
	return err;
	*val = IN_FROM_REG(regval, channel);
	return 0;
	}

	static int adm9240_in_write(struct device *dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	int reg;

	switch (attr) {
	case hwmon_in_min:
	reg = ADM9240_REG_IN_MIN(channel);
	break;
	case hwmon_in_max:
	reg = ADM9240_REG_IN_MAX(channel);
	break;
	default:
	return -EOPNOTSUPP;
	}
	return regmap_write(data->regmap, reg, IN_TO_REG(val, channel));
	}

	static int adm9240_fan_read(struct device dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int err;

	switch (attr) {
	case hwmon_fan_input:
	mutex_lock(&data->update_lock);
	err = regmap_read(data->regmap, ADM9240_REG_FAN(channel), &regval);
	if (err < 0) {
	mutex_unlock(&data->update_lock);
	return err;
	}
	if (regval == 255 && data->fan_div[channel] < 3) {
	/* adjust fan clock divider on overflow */
	err = adm9240_write_fan_div(data, channel,
	++data->fan_div[channel]);
	if (err) {
	mutex_unlock(&data->update_lock);
	return err;
	}
	}
	*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
	mutex_unlock(&data->update_lock);
	break;
	case hwmon_fan_div:
	*val = BIT(data->fan_div[channel]);
	break;
	case hwmon_fan_min:
	err = regmap_read(data->regmap, ADM9240_REG_FAN_MIN(channel), &regval);
	if (err < 0)
	return err;
	*val = FAN_FROM_REG(regval, BIT(data->fan_div[channel]));
	break;
	case hwmon_fan_alarm:
	err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
	if (err < 0)
	return err;
	*val = !!(regval & BIT(channel + 6));
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_fan_write(struct device *dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	int err;

	switch (attr) {
	case hwmon_fan_min:
	err = adm9240_fan_min_write(data, channel, val);
	if (err < 0)
	return err;
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_temp_read(struct device dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	unsigned int regval;
	int err, temp;

	switch (attr) {
	case hwmon_temp_input:
	err = regmap_read(data->regmap, ADM9240_REG_TEMP, &regval);
	if (err < 0)
	return err;
	temp = regval << 1;
	err = regmap_read(data->regmap, ADM9240_REG_TEMP_CONF, &regval);
	if (err < 0)
	return err;
	temp \|= regval >> 7;
	val = sign_extend32(temp, 8) 500;
	break;
	case hwmon_temp_max:
	err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(0), &regval);
	if (err < 0)
	return err;
	val = (s8)regval 1000;
	break;
	case hwmon_temp_max_hyst:
	err = regmap_read(data->regmap, ADM9240_REG_TEMP_MAX(1), &regval);
	if (err < 0)
	return err;
	val = (s8)regval 1000;
	break;
	case hwmon_temp_alarm:
	err = regmap_read(data->regmap, ADM9240_REG_INT(0), &regval);
	if (err < 0)
	return err;
	*val = !!(regval & BIT(4));
	break;
	default:
	return -EOPNOTSUPP;
	}
	return 0;
	}

	static int adm9240_temp_write(struct device *dev, u32 attr, int channel, long val)
	{
	struct adm9240_data *data = dev_get_drvdata(dev);
	int reg;

	switch (attr) {
	case hwmon_temp_max:
	reg = ADM9240_REG_TEMP_MAX(0);
	break;
	case hwmon_temp_max_hyst:
	reg = ADM9240_REG_TEMP_MAX(1);
	break;
	default:
	return -EOPNOTSUPP;
	}
	return regmap_write(data->regmap, reg, TEMP_TO_REG(val));
	}

	static int adm9240_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
	int channel, long *val)
	{
	switch (type) {
	case hwmon_chip:
	return adm9240_chip_read(dev, attr, val);
	case hwmon_intrusion:
	return adm9240_intrusion_read(dev, attr, val);
	case hwmon_in:
	return adm9240_in_read(dev, attr, channel, val);
	case hwmon_fan:
	return adm9240_fan_read(dev, attr, channel, val);
	case hwmon_temp:
	return adm9240_temp_read(dev, attr, channel, val);
	default:
	return -EOPNOTSUPP;
	}
	}

	static int adm9240_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
	int channel, long val)
	{
	switch (type) {
	case hwmon_intrusion:
	return adm9240_intrusion_write(dev, attr, val);
	case hwmon_in:
	return adm9240_in_write(dev, attr, channel, val);
	case hwmon_fan:
	return adm9240_fan_write(dev, attr, channel, val);
	case hwmon_temp:
	return adm9240_temp_write(dev, attr, channel, val);
	default:
	return -EOPNOTSUPP;
	}
	}

	static umode_t adm9240_is_visible(const void *_data, enum hwmon_sensor_types type,
	u32 attr, int channel)
	{
	umode_t mode = 0;

	switch (type) {
	case hwmon_chip:
	switch (attr) {
	case hwmon_chip_alarms:
	mode = 0444;
	break;
	default:
	break;
	}
	break;
	case hwmon_intrusion:
	switch (attr) {
	case hwmon_intrusion_alarm:
	mode = 0644;
	break;
	default:
	break;
	}
	break;
	case hwmon_temp:
	switch (attr) {
	case hwmon_temp:
	case hwmon_temp_alarm:
	mode = 0444;
	break;
	case hwmon_temp_max:
	case hwmon_temp_max_hyst:
	mode = 0644;
	break;
	default:
	break;
	}
	break;
	case hwmon_fan:
	switch (attr) {
	case hwmon_fan_input:
	case hwmon_fan_div:
	case hwmon_fan_alarm:
	mode = 0444;
	break;
	case hwmon_fan_min:
	mode = 0644;
	break;
	default:
	break;
	}
	break;
	case hwmon_in:
	switch (attr) {
	case hwmon_in_input:
	case hwmon_in_alarm:
	mode = 0444;
	break;
	case hwmon_in_min:
	case hwmon_in_max:
	mode = 0644;
	break;
	default:
	break;
	}
	break;
	default:
	break;
	}
	return mode;
	}

	static const struct hwmon_ops adm9240_hwmon_ops = {
	.is_visible = adm9240_is_visible,
	.read = adm9240_read,
	.write = adm9240_write,
	};

	static const struct hwmon_channel_info *adm9240_info[] = {
	HWMON_CHANNEL_INFO(chip, HWMON_C_ALARMS),
	HWMON_CHANNEL_INFO(intrusion, HWMON_INTRUSION_ALARM),
	HWMON_CHANNEL_INFO(temp,
	HWMON_T_INPUT \| HWMON_T_MAX \| HWMON_T_MAX_HYST \| HWMON_T_ALARM),
	HWMON_CHANNEL_INFO(in,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM,
	HWMON_I_INPUT \| HWMON_I_MIN \| HWMON_I_MAX \| HWMON_I_ALARM),
	HWMON_CHANNEL_INFO(fan,
	HWMON_F_INPUT \| HWMON_F_MIN \| HWMON_F_DIV \| HWMON_F_ALARM,
	HWMON_F_INPUT \| HWMON_F_MIN \| HWMON_F_DIV \| HWMON_F_ALARM),
	NULL
	};

	static const struct hwmon_chip_info adm9240_chip_info = {
	.ops = &adm9240_hwmon_ops,
	.info = adm9240_info,
	};

	static bool adm9240_volatile_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case ADM9240_REG_IN(0) ... ADM9240_REG_IN(5):
	case ADM9240_REG_FAN(0) ... ADM9240_REG_FAN(1):
	case ADM9240_REG_INT(0) ... ADM9240_REG_INT(1):
	case ADM9240_REG_TEMP:
	case ADM9240_REG_TEMP_CONF:
	case ADM9240_REG_VID_FAN_DIV:
	case ADM9240_REG_VID4:
	case ADM9240_REG_ANALOG_OUT:
	return true;
	default:
	return false;
	}
	}

	static const struct regmap_config adm9240_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.use_single_read = true,
	.use_single_write = true,
	.volatile_reg = adm9240_volatile_reg,
	};

	static int adm9240_probe(struct i2c_client *client)
	{
	struct device *dev = &client->dev;
	struct device *hwmon_dev;
	struct adm9240_data *data;
	int err;

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

	data->dev = dev;
	mutex_init(&data->update_lock);
	data->regmap = devm_regmap_init_i2c(client, &adm9240_regmap_config);
	if (IS_ERR(data->regmap))
	return PTR_ERR(data->regmap);

	err = adm9240_init_client(data);
	if (err < 0)
	return err;

	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, data,
	&adm9240_chip_info,
	adm9240_groups);
	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static const struct i2c_device_id adm9240_id[] = {
	{ "adm9240", adm9240 },
	{ "ds1780", ds1780 },
	{ "lm81", lm81 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, adm9240_id);

	static struct i2c_driver adm9240_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
	.name = "adm9240",
	},
	.probe_new = adm9240_probe,
	.id_table = adm9240_id,
	.detect = adm9240_detect,
	.address_list = normal_i2c,
	};

	module_i2c_driver(adm9240_driver);

	MODULE_AUTHOR("Michiel Rook <michiel@grendelproject.nl>, "
	"Grant Coady <gcoady.lk@gmail.com> and others");
	MODULE_DESCRIPTION("ADM9240/DS1780/LM81 driver");
	MODULE_LICENSE("GPL");