/*
   * A hwmon driver for the Analog Devices ADT7470
   * Copyright (C) 2007 IBM
   *
   * Author: Darrick J. Wong <djwong@us.ibm.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */

  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

  #include <linux/module.h>
  #include <linux/jiffies.h>
  #include <linux/i2c.h>
  #include <linux/hwmon.h>
  #include <linux/hwmon-sysfs.h>
  #include <linux/err.h>
  #include <linux/mutex.h>
  #include <linux/delay.h>
  #include <linux/log2.h>

  #include <linux/kthread.h>

  #include <linux/slab.h>

  
  /* Addresses to scan */

  static const unsigned short normal_i2c[] = { 0x2C, 0x2E, 0x2F, I2C_CLIENT_END };

  /* ADT7470 registers */
  #define ADT7470_REG_BASE_ADDR			0x20
  #define ADT7470_REG_TEMP_BASE_ADDR		0x20
  #define ADT7470_REG_TEMP_MAX_ADDR		0x29
  #define ADT7470_REG_FAN_BASE_ADDR		0x2A
  #define ADT7470_REG_FAN_MAX_ADDR		0x31
  #define ADT7470_REG_PWM_BASE_ADDR		0x32
  #define ADT7470_REG_PWM_MAX_ADDR		0x35
  #define ADT7470_REG_PWM_MAX_BASE_ADDR		0x38
  #define ADT7470_REG_PWM_MAX_MAX_ADDR		0x3B
  #define ADT7470_REG_CFG				0x40
  #define		ADT7470_FSPD_MASK		0x04
  #define ADT7470_REG_ALARM1			0x41

  #define		ADT7470_R1T_ALARM		0x01
  #define		ADT7470_R2T_ALARM		0x02
  #define		ADT7470_R3T_ALARM		0x04
  #define		ADT7470_R4T_ALARM		0x08
  #define		ADT7470_R5T_ALARM		0x10
  #define		ADT7470_R6T_ALARM		0x20
  #define		ADT7470_R7T_ALARM		0x40
  #define		ADT7470_OOL_ALARM		0x80

  #define ADT7470_REG_ALARM2			0x42

  #define		ADT7470_R8T_ALARM		0x01
  #define		ADT7470_R9T_ALARM		0x02
  #define		ADT7470_R10T_ALARM		0x04
  #define		ADT7470_FAN1_ALARM		0x10
  #define		ADT7470_FAN2_ALARM		0x20
  #define		ADT7470_FAN3_ALARM		0x40
  #define		ADT7470_FAN4_ALARM		0x80

  #define ADT7470_REG_TEMP_LIMITS_BASE_ADDR	0x44
  #define ADT7470_REG_TEMP_LIMITS_MAX_ADDR	0x57
  #define ADT7470_REG_FAN_MIN_BASE_ADDR		0x58
  #define ADT7470_REG_FAN_MIN_MAX_ADDR		0x5F
  #define ADT7470_REG_FAN_MAX_BASE_ADDR		0x60
  #define ADT7470_REG_FAN_MAX_MAX_ADDR		0x67
  #define ADT7470_REG_PWM_CFG_BASE_ADDR		0x68
  #define ADT7470_REG_PWM12_CFG			0x68
  #define		ADT7470_PWM2_AUTO_MASK		0x40
  #define		ADT7470_PWM1_AUTO_MASK		0x80

  #define		ADT7470_PWM_AUTO_MASK		0xC0

  #define ADT7470_REG_PWM34_CFG			0x69
  #define		ADT7470_PWM3_AUTO_MASK		0x40
  #define		ADT7470_PWM4_AUTO_MASK		0x80
  #define	ADT7470_REG_PWM_MIN_BASE_ADDR		0x6A
  #define ADT7470_REG_PWM_MIN_MAX_ADDR		0x6D
  #define ADT7470_REG_PWM_TEMP_MIN_BASE_ADDR	0x6E
  #define ADT7470_REG_PWM_TEMP_MIN_MAX_ADDR	0x71
  #define ADT7470_REG_ACOUSTICS12			0x75
  #define ADT7470_REG_ACOUSTICS34			0x76
  #define ADT7470_REG_DEVICE			0x3D
  #define ADT7470_REG_VENDOR			0x3E
  #define ADT7470_REG_REVISION			0x3F
  #define ADT7470_REG_ALARM1_MASK			0x72
  #define ADT7470_REG_ALARM2_MASK			0x73
  #define ADT7470_REG_PWM_AUTO_TEMP_BASE_ADDR	0x7C
  #define ADT7470_REG_PWM_AUTO_TEMP_MAX_ADDR	0x7D
  #define ADT7470_REG_MAX_ADDR			0x81
  
  #define ADT7470_TEMP_COUNT	10
  #define ADT7470_TEMP_REG(x)	(ADT7470_REG_TEMP_BASE_ADDR + (x))
  #define ADT7470_TEMP_MIN_REG(x) (ADT7470_REG_TEMP_LIMITS_BASE_ADDR + ((x) * 2))
  #define ADT7470_TEMP_MAX_REG(x) (ADT7470_REG_TEMP_LIMITS_BASE_ADDR + \
  				((x) * 2) + 1)
  
  #define ADT7470_FAN_COUNT	4
  #define ADT7470_REG_FAN(x)	(ADT7470_REG_FAN_BASE_ADDR + ((x) * 2))
  #define ADT7470_REG_FAN_MIN(x)	(ADT7470_REG_FAN_MIN_BASE_ADDR + ((x) * 2))
  #define ADT7470_REG_FAN_MAX(x)	(ADT7470_REG_FAN_MAX_BASE_ADDR + ((x) * 2))
  
  #define ADT7470_PWM_COUNT	4
  #define ADT7470_REG_PWM(x)	(ADT7470_REG_PWM_BASE_ADDR + (x))
  #define ADT7470_REG_PWM_MAX(x)	(ADT7470_REG_PWM_MAX_BASE_ADDR + (x))
  #define ADT7470_REG_PWM_MIN(x)	(ADT7470_REG_PWM_MIN_BASE_ADDR + (x))
  #define ADT7470_REG_PWM_TMIN(x)	(ADT7470_REG_PWM_TEMP_MIN_BASE_ADDR + (x))
  #define ADT7470_REG_PWM_CFG(x)	(ADT7470_REG_PWM_CFG_BASE_ADDR + ((x) / 2))
  #define ADT7470_REG_PWM_AUTO_TEMP(x)	(ADT7470_REG_PWM_AUTO_TEMP_BASE_ADDR + \
  					((x) / 2))

  #define ALARM2(x)		((x) << 8)

  #define ADT7470_VENDOR		0x41
  #define ADT7470_DEVICE		0x70
  /* datasheet only mentions a revision 2 */
  #define ADT7470_REVISION	0x02
  
  /* "all temps" according to hwmon sysfs interface spec */
  #define ADT7470_PWM_ALL_TEMPS	0x3FF
  
  /* How often do we reread sensors values? (In jiffies) */
  #define SENSOR_REFRESH_INTERVAL	(5 * HZ)
  
  /* How often do we reread sensor limit values? (In jiffies) */
  #define LIMIT_REFRESH_INTERVAL	(60 * HZ)

  /* Wait at least 200ms per sensor for 10 sensors */
  #define TEMP_COLLECTION_TIME	2000

  /* auto update thing won't fire more than every 2s */
  #define AUTO_UPDATE_INTERVAL	2000

  /* datasheet says to divide this number by the fan reading to get fan rpm */
  #define FAN_PERIOD_TO_RPM(x)	((90000 * 60) / (x))
  #define FAN_RPM_TO_PERIOD	FAN_PERIOD_TO_RPM
  #define FAN_PERIOD_INVALID	65535
  #define FAN_DATA_VALID(x)	((x) && (x) != FAN_PERIOD_INVALID)
  
  struct adt7470_data {

  	struct device		*hwmon_dev;

  	struct attribute_group	attrs;
  	struct mutex		lock;
  	char			sensors_valid;
  	char			limits_valid;
  	unsigned long		sensors_last_updated;	/* In jiffies */
  	unsigned long		limits_last_updated;	/* In jiffies */

  	int			num_temp_sensors;	/* -1 = probe */

  	int			temperatures_probed;

  	s8			temp[ADT7470_TEMP_COUNT];
  	s8			temp_min[ADT7470_TEMP_COUNT];
  	s8			temp_max[ADT7470_TEMP_COUNT];
  	u16			fan[ADT7470_FAN_COUNT];
  	u16			fan_min[ADT7470_FAN_COUNT];
  	u16			fan_max[ADT7470_FAN_COUNT];

  	u16			alarm;
  	u16			alarms_mask;

  	u8			force_pwm_max;
  	u8			pwm[ADT7470_PWM_COUNT];
  	u8			pwm_max[ADT7470_PWM_COUNT];
  	u8			pwm_automatic[ADT7470_PWM_COUNT];
  	u8			pwm_min[ADT7470_PWM_COUNT];
  	s8			pwm_tmin[ADT7470_PWM_COUNT];
  	u8			pwm_auto_temp[ADT7470_PWM_COUNT];

  
  	struct task_struct	*auto_update;
  	struct completion	auto_update_stop;
  	unsigned int		auto_update_interval;

  };

  static int adt7470_probe(struct i2c_client *client,
  			 const struct i2c_device_id *id);

  static int adt7470_detect(struct i2c_client *client,

  			  struct i2c_board_info *info);
  static int adt7470_remove(struct i2c_client *client);
  
  static const struct i2c_device_id adt7470_id[] = {

  	{ "adt7470", 0 },

  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, adt7470_id);

  
  static struct i2c_driver adt7470_driver = {

  	.class		= I2C_CLASS_HWMON,

  	.driver = {
  		.name	= "adt7470",
  	},

  	.probe		= adt7470_probe,
  	.remove		= adt7470_remove,
  	.id_table	= adt7470_id,
  	.detect		= adt7470_detect,

  	.address_list	= normal_i2c,

  };
  
  /*
   * 16-bit registers on the ADT7470 are low-byte first.  The data sheet says
   * that the low byte must be read before the high byte.
   */
  static inline int adt7470_read_word_data(struct i2c_client *client, u8 reg)
  {
  	u16 foo;
  	foo = i2c_smbus_read_byte_data(client, reg);
  	foo |= ((u16)i2c_smbus_read_byte_data(client, reg + 1) << 8);
  	return foo;
  }
  
  static inline int adt7470_write_word_data(struct i2c_client *client, u8 reg,
  					  u16 value)
  {
  	return i2c_smbus_write_byte_data(client, reg, value & 0xFF)
  	       && i2c_smbus_write_byte_data(client, reg + 1, value >> 8);
  }
  
  static void adt7470_init_client(struct i2c_client *client)
  {
  	int reg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
  
  	if (reg < 0) {
  		dev_err(&client->dev, "cannot read configuration register
  ");
  	} else {
  		/* start monitoring (and do a self-test) */
  		i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, reg | 3);
  	}
  }

  /* Probe for temperature sensors.  Assumes lock is held */
  static int adt7470_read_temperatures(struct i2c_client *client,
  				     struct adt7470_data *data)

  {

  	unsigned long res;

  	int i;

  	u8 cfg, pwm[4], pwm_cfg[2];

  	/* save pwm[1-4] config register */
  	pwm_cfg[0] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM_CFG(0));
  	pwm_cfg[1] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM_CFG(2));
  
  	/* set manual pwm to whatever it is set to now */
  	for (i = 0; i < ADT7470_FAN_COUNT; i++)
  		pwm[i] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM(i));
  
  	/* put pwm in manual mode */
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(0),
  		pwm_cfg[0] & ~(ADT7470_PWM_AUTO_MASK));
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(2),
  		pwm_cfg[1] & ~(ADT7470_PWM_AUTO_MASK));
  
  	/* write pwm control to whatever it was */
  	for (i = 0; i < ADT7470_FAN_COUNT; i++)
  		i2c_smbus_write_byte_data(client, ADT7470_REG_PWM(i), pwm[i]);

  	/* start reading temperature sensors */
  	cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
  	cfg |= 0x80;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);

  	/* Delay is 200ms * number of temp sensors. */

  	res = msleep_interruptible((data->num_temp_sensors >= 0 ?
  				    data->num_temp_sensors * 200 :
  				    TEMP_COLLECTION_TIME));

  
  	/* done reading temperature sensors */
  	cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
  	cfg &= ~0x80;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);

  	/* restore pwm[1-4] config registers */
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(0), pwm_cfg[0]);
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(2), pwm_cfg[1]);

  	if (res) {

  		pr_err("ha ha, interrupted
  ");

  		return -EAGAIN;
  	}
  
  	/* Only count fans if we have to */
  	if (data->num_temp_sensors >= 0)
  		return 0;
  
  	for (i = 0; i < ADT7470_TEMP_COUNT; i++) {

  		data->temp[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_TEMP_REG(i));

  		if (data->temp[i])
  			data->num_temp_sensors = i + 1;
  	}
  	data->temperatures_probed = 1;
  	return 0;
  }

  static int adt7470_update_thread(void *p)
  {
  	struct i2c_client *client = p;
  	struct adt7470_data *data = i2c_get_clientdata(client);
  
  	while (!kthread_should_stop()) {
  		mutex_lock(&data->lock);
  		adt7470_read_temperatures(client, data);
  		mutex_unlock(&data->lock);
  		if (kthread_should_stop())
  			break;
  		msleep_interruptible(data->auto_update_interval);
  	}
  
  	complete_all(&data->auto_update_stop);
  	return 0;
  }
  
  static struct adt7470_data *adt7470_update_device(struct device *dev)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);
  	unsigned long local_jiffies = jiffies;
  	u8 cfg;
  	int i;
  	int need_sensors = 1;
  	int need_limits = 1;
  
  	/*
  	 * Figure out if we need to update the shadow registers.
  	 * Lockless means that we may occasionally report out of
  	 * date data.
  	 */
  	if (time_before(local_jiffies, data->sensors_last_updated +
  			SENSOR_REFRESH_INTERVAL) &&
  	    data->sensors_valid)
  		need_sensors = 0;
  
  	if (time_before(local_jiffies, data->limits_last_updated +
  			LIMIT_REFRESH_INTERVAL) &&
  	    data->limits_valid)
  		need_limits = 0;
  
  	if (!need_sensors && !need_limits)
  		return data;
  
  	mutex_lock(&data->lock);
  	if (!need_sensors)
  		goto no_sensor_update;
  
  	if (!data->temperatures_probed)
  		adt7470_read_temperatures(client, data);
  	else

  		for (i = 0; i < ADT7470_TEMP_COUNT; i++)

  			data->temp[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_TEMP_REG(i));

  	for (i = 0; i < ADT7470_FAN_COUNT; i++)
  		data->fan[i] = adt7470_read_word_data(client,
  						ADT7470_REG_FAN(i));
  
  	for (i = 0; i < ADT7470_PWM_COUNT; i++) {
  		int reg;
  		int reg_mask;
  
  		data->pwm[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_REG_PWM(i));
  
  		if (i % 2)
  			reg_mask = ADT7470_PWM2_AUTO_MASK;
  		else
  			reg_mask = ADT7470_PWM1_AUTO_MASK;
  
  		reg = ADT7470_REG_PWM_CFG(i);
  		if (i2c_smbus_read_byte_data(client, reg) & reg_mask)
  			data->pwm_automatic[i] = 1;
  		else
  			data->pwm_automatic[i] = 0;
  
  		reg = ADT7470_REG_PWM_AUTO_TEMP(i);
  		cfg = i2c_smbus_read_byte_data(client, reg);
  		if (!(i % 2))
  			data->pwm_auto_temp[i] = cfg >> 4;
  		else
  			data->pwm_auto_temp[i] = cfg & 0xF;
  	}
  
  	if (i2c_smbus_read_byte_data(client, ADT7470_REG_CFG) &
  	    ADT7470_FSPD_MASK)
  		data->force_pwm_max = 1;
  	else
  		data->force_pwm_max = 0;

  	data->alarm = i2c_smbus_read_byte_data(client, ADT7470_REG_ALARM1);
  	if (data->alarm & ADT7470_OOL_ALARM)
  		data->alarm |= ALARM2(i2c_smbus_read_byte_data(client,
  							ADT7470_REG_ALARM2));

  	data->alarms_mask = adt7470_read_word_data(client,
  						   ADT7470_REG_ALARM1_MASK);
  
  	data->sensors_last_updated = local_jiffies;
  	data->sensors_valid = 1;
  
  no_sensor_update:

  	if (!need_limits)

  		goto out;
  
  	for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
  		data->temp_min[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_TEMP_MIN_REG(i));
  		data->temp_max[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_TEMP_MAX_REG(i));
  	}
  
  	for (i = 0; i < ADT7470_FAN_COUNT; i++) {
  		data->fan_min[i] = adt7470_read_word_data(client,
  						ADT7470_REG_FAN_MIN(i));
  		data->fan_max[i] = adt7470_read_word_data(client,
  						ADT7470_REG_FAN_MAX(i));
  	}
  
  	for (i = 0; i < ADT7470_PWM_COUNT; i++) {
  		data->pwm_max[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_REG_PWM_MAX(i));
  		data->pwm_min[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_REG_PWM_MIN(i));
  		data->pwm_tmin[i] = i2c_smbus_read_byte_data(client,
  						ADT7470_REG_PWM_TMIN(i));
  	}
  
  	data->limits_last_updated = local_jiffies;
  	data->limits_valid = 1;
  
  out:
  	mutex_unlock(&data->lock);
  	return data;
  }

  static ssize_t show_auto_update_interval(struct device *dev,
  					 struct device_attribute *devattr,
  					 char *buf)
  {
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->auto_update_interval);
  }
  
  static ssize_t set_auto_update_interval(struct device *dev,
  					struct device_attribute *devattr,
  					const char *buf,
  					size_t count)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);
  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = SENSORS_LIMIT(temp, 0, 60000);
  
  	mutex_lock(&data->lock);
  	data->auto_update_interval = temp;
  	mutex_unlock(&data->lock);
  
  	return count;
  }

  static ssize_t show_num_temp_sensors(struct device *dev,
  				     struct device_attribute *devattr,
  				     char *buf)
  {
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->num_temp_sensors);
  }
  
  static ssize_t set_num_temp_sensors(struct device *dev,
  				    struct device_attribute *devattr,
  				    const char *buf,
  				    size_t count)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);
  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = SENSORS_LIMIT(temp, -1, 10);
  
  	mutex_lock(&data->lock);
  	data->num_temp_sensors = temp;

  	if (temp < 0)
  		data->temperatures_probed = 0;

  	mutex_unlock(&data->lock);
  
  	return count;
  }

  static ssize_t show_temp_min(struct device *dev,
  			     struct device_attribute *devattr,
  			     char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", 1000 * data->temp_min[attr->index]);
  }
  
  static ssize_t set_temp_min(struct device *dev,
  			    struct device_attribute *devattr,
  			    const char *buf,
  			    size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;

  	temp = DIV_ROUND_CLOSEST(temp, 1000);

  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->temp_min[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_TEMP_MIN_REG(attr->index),
  				  temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_temp_max(struct device *dev,
  			     struct device_attribute *devattr,
  			     char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", 1000 * data->temp_max[attr->index]);
  }
  
  static ssize_t set_temp_max(struct device *dev,
  			    struct device_attribute *devattr,
  			    const char *buf,
  			    size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;

  	temp = DIV_ROUND_CLOSEST(temp, 1000);

  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->temp_max[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_TEMP_MAX_REG(attr->index),
  				  temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
  			 char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", 1000 * data->temp[attr->index]);
  }

  static ssize_t show_alarm_mask(struct device *dev,

  			   struct device_attribute *devattr,
  			   char *buf)
  {

  	struct adt7470_data *data = adt7470_update_device(dev);

  	return sprintf(buf, "%x
  ", data->alarms_mask);

  }
  
  static ssize_t show_fan_max(struct device *dev,
  			    struct device_attribute *devattr,
  			    char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  
  	if (FAN_DATA_VALID(data->fan_max[attr->index]))
  		return sprintf(buf, "%d
  ",
  			       FAN_PERIOD_TO_RPM(data->fan_max[attr->index]));
  	else
  		return sprintf(buf, "0
  ");
  }
  
  static ssize_t set_fan_max(struct device *dev,
  			   struct device_attribute *devattr,
  			   const char *buf, size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp) || !temp)

  		return -EINVAL;

  	temp = FAN_RPM_TO_PERIOD(temp);

  	temp = SENSORS_LIMIT(temp, 1, 65534);

  
  	mutex_lock(&data->lock);
  	data->fan_max[attr->index] = temp;
  	adt7470_write_word_data(client, ADT7470_REG_FAN_MAX(attr->index), temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_fan_min(struct device *dev,
  			    struct device_attribute *devattr,
  			    char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  
  	if (FAN_DATA_VALID(data->fan_min[attr->index]))
  		return sprintf(buf, "%d
  ",
  			       FAN_PERIOD_TO_RPM(data->fan_min[attr->index]));
  	else
  		return sprintf(buf, "0
  ");
  }
  
  static ssize_t set_fan_min(struct device *dev,
  			   struct device_attribute *devattr,
  			   const char *buf, size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp) || !temp)

  		return -EINVAL;

  	temp = FAN_RPM_TO_PERIOD(temp);

  	temp = SENSORS_LIMIT(temp, 1, 65534);

  
  	mutex_lock(&data->lock);
  	data->fan_min[attr->index] = temp;
  	adt7470_write_word_data(client, ADT7470_REG_FAN_MIN(attr->index), temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_fan(struct device *dev, struct device_attribute *devattr,
  			char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  
  	if (FAN_DATA_VALID(data->fan[attr->index]))
  		return sprintf(buf, "%d
  ",
  			       FAN_PERIOD_TO_RPM(data->fan[attr->index]));
  	else
  		return sprintf(buf, "0
  ");
  }
  
  static ssize_t show_force_pwm_max(struct device *dev,
  				  struct device_attribute *devattr,
  				  char *buf)
  {
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->force_pwm_max);
  }
  
  static ssize_t set_force_pwm_max(struct device *dev,
  				 struct device_attribute *devattr,
  				 const char *buf,
  				 size_t count)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	u8 reg;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;

  	mutex_lock(&data->lock);
  	data->force_pwm_max = temp;
  	reg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
  	if (temp)
  		reg |= ADT7470_FSPD_MASK;
  	else
  		reg &= ~ADT7470_FSPD_MASK;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, reg);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm(struct device *dev, struct device_attribute *devattr,
  			char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->pwm[attr->index]);
  }
  
  static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
  			const char *buf, size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->pwm[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM(attr->index), temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm_max(struct device *dev,
  			    struct device_attribute *devattr,
  			    char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->pwm_max[attr->index]);
  }
  
  static ssize_t set_pwm_max(struct device *dev,
  			   struct device_attribute *devattr,
  			   const char *buf,
  			   size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->pwm_max[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_MAX(attr->index),
  				  temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm_min(struct device *dev,
  			    struct device_attribute *devattr,
  			    char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", data->pwm_min[attr->index]);
  }
  
  static ssize_t set_pwm_min(struct device *dev,
  			   struct device_attribute *devattr,
  			   const char *buf,
  			   size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->pwm_min[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_MIN(attr->index),
  				  temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm_tmax(struct device *dev,
  			     struct device_attribute *devattr,
  			     char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	/* the datasheet says that tmax = tmin + 20C */
  	return sprintf(buf, "%d
  ", 1000 * (20 + data->pwm_tmin[attr->index]));
  }
  
  static ssize_t show_pwm_tmin(struct device *dev,
  			     struct device_attribute *devattr,
  			     char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", 1000 * data->pwm_tmin[attr->index]);
  }
  
  static ssize_t set_pwm_tmin(struct device *dev,
  			    struct device_attribute *devattr,
  			    const char *buf,
  			    size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	long temp;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;

  	temp = DIV_ROUND_CLOSEST(temp, 1000);

  	temp = SENSORS_LIMIT(temp, 0, 255);

  
  	mutex_lock(&data->lock);
  	data->pwm_tmin[attr->index] = temp;
  	i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_TMIN(attr->index),
  				  temp);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm_auto(struct device *dev,
  			     struct device_attribute *devattr,
  			     char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	return sprintf(buf, "%d
  ", 1 + data->pwm_automatic[attr->index]);
  }
  
  static ssize_t set_pwm_auto(struct device *dev,
  			    struct device_attribute *devattr,
  			    const char *buf,
  			    size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	int pwm_auto_reg = ADT7470_REG_PWM_CFG(attr->index);
  	int pwm_auto_reg_mask;

  	long temp;

  	u8 reg;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;

  	if (attr->index % 2)
  		pwm_auto_reg_mask = ADT7470_PWM2_AUTO_MASK;
  	else
  		pwm_auto_reg_mask = ADT7470_PWM1_AUTO_MASK;
  
  	if (temp != 2 && temp != 1)
  		return -EINVAL;
  	temp--;
  
  	mutex_lock(&data->lock);
  	data->pwm_automatic[attr->index] = temp;
  	reg = i2c_smbus_read_byte_data(client, pwm_auto_reg);
  	if (temp)
  		reg |= pwm_auto_reg_mask;
  	else
  		reg &= ~pwm_auto_reg_mask;
  	i2c_smbus_write_byte_data(client, pwm_auto_reg, reg);
  	mutex_unlock(&data->lock);
  
  	return count;
  }
  
  static ssize_t show_pwm_auto_temp(struct device *dev,
  				  struct device_attribute *devattr,
  				  char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  	u8 ctrl = data->pwm_auto_temp[attr->index];
  
  	if (ctrl)
  		return sprintf(buf, "%d
  ", 1 << (ctrl - 1));
  	else
  		return sprintf(buf, "%d
  ", ADT7470_PWM_ALL_TEMPS);
  }
  
  static int cvt_auto_temp(int input)
  {
  	if (input == ADT7470_PWM_ALL_TEMPS)
  		return 0;

  	if (input < 1 || !is_power_of_2(input))

  		return -EINVAL;
  	return ilog2(input) + 1;
  }
  
  static ssize_t set_pwm_auto_temp(struct device *dev,
  				 struct device_attribute *devattr,
  				 const char *buf,
  				 size_t count)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct i2c_client *client = to_i2c_client(dev);
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	int pwm_auto_reg = ADT7470_REG_PWM_AUTO_TEMP(attr->index);

  	long temp;

  	u8 reg;

  	if (kstrtol(buf, 10, &temp))

  		return -EINVAL;
  
  	temp = cvt_auto_temp(temp);

  	if (temp < 0)
  		return temp;
  
  	mutex_lock(&data->lock);
  	data->pwm_automatic[attr->index] = temp;
  	reg = i2c_smbus_read_byte_data(client, pwm_auto_reg);
  
  	if (!(attr->index % 2)) {
  		reg &= 0xF;
  		reg |= (temp << 4) & 0xF0;
  	} else {
  		reg &= 0xF0;
  		reg |= temp & 0xF;
  	}
  
  	i2c_smbus_write_byte_data(client, pwm_auto_reg, reg);
  	mutex_unlock(&data->lock);
  
  	return count;
  }

  static ssize_t show_alarm(struct device *dev,
  			  struct device_attribute *devattr,
  			  char *buf)
  {
  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  	struct adt7470_data *data = adt7470_update_device(dev);
  
  	if (data->alarm & attr->index)
  		return sprintf(buf, "1
  ");
  	else
  		return sprintf(buf, "0
  ");
  }
  
  static DEVICE_ATTR(alarm_mask, S_IRUGO, show_alarm_mask, NULL);

  static DEVICE_ATTR(num_temp_sensors, S_IWUSR | S_IRUGO, show_num_temp_sensors,
  		   set_num_temp_sensors);

  static DEVICE_ATTR(auto_update_interval, S_IWUSR | S_IRUGO,
  		   show_auto_update_interval, set_auto_update_interval);

  
  static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 0);
  static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 1);
  static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 2);
  static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 3);
  static SENSOR_DEVICE_ATTR(temp5_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 4);
  static SENSOR_DEVICE_ATTR(temp6_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 5);
  static SENSOR_DEVICE_ATTR(temp7_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 6);
  static SENSOR_DEVICE_ATTR(temp8_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 7);
  static SENSOR_DEVICE_ATTR(temp9_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 8);
  static SENSOR_DEVICE_ATTR(temp10_max, S_IWUSR | S_IRUGO, show_temp_max,
  		    set_temp_max, 9);
  
  static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 0);
  static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 1);
  static SENSOR_DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 2);
  static SENSOR_DEVICE_ATTR(temp4_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 3);
  static SENSOR_DEVICE_ATTR(temp5_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 4);
  static SENSOR_DEVICE_ATTR(temp6_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 5);
  static SENSOR_DEVICE_ATTR(temp7_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 6);
  static SENSOR_DEVICE_ATTR(temp8_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 7);
  static SENSOR_DEVICE_ATTR(temp9_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 8);
  static SENSOR_DEVICE_ATTR(temp10_min, S_IWUSR | S_IRUGO, show_temp_min,
  		    set_temp_min, 9);
  
  static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
  static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
  static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
  static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
  static SENSOR_DEVICE_ATTR(temp5_input, S_IRUGO, show_temp, NULL, 4);
  static SENSOR_DEVICE_ATTR(temp6_input, S_IRUGO, show_temp, NULL, 5);
  static SENSOR_DEVICE_ATTR(temp7_input, S_IRUGO, show_temp, NULL, 6);
  static SENSOR_DEVICE_ATTR(temp8_input, S_IRUGO, show_temp, NULL, 7);
  static SENSOR_DEVICE_ATTR(temp9_input, S_IRUGO, show_temp, NULL, 8);
  static SENSOR_DEVICE_ATTR(temp10_input, S_IRUGO, show_temp, NULL, 9);

  static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R1T_ALARM);
  static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R2T_ALARM);
  static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R3T_ALARM);
  static SENSOR_DEVICE_ATTR(temp4_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R4T_ALARM);
  static SENSOR_DEVICE_ATTR(temp5_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R5T_ALARM);
  static SENSOR_DEVICE_ATTR(temp6_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R6T_ALARM);
  static SENSOR_DEVICE_ATTR(temp7_alarm, S_IRUGO, show_alarm, NULL,
  			  ADT7470_R7T_ALARM);
  static SENSOR_DEVICE_ATTR(temp8_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_R8T_ALARM));
  static SENSOR_DEVICE_ATTR(temp9_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_R9T_ALARM));
  static SENSOR_DEVICE_ATTR(temp10_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_R10T_ALARM));

  static SENSOR_DEVICE_ATTR(fan1_max, S_IWUSR | S_IRUGO, show_fan_max,
  		    set_fan_max, 0);
  static SENSOR_DEVICE_ATTR(fan2_max, S_IWUSR | S_IRUGO, show_fan_max,
  		    set_fan_max, 1);
  static SENSOR_DEVICE_ATTR(fan3_max, S_IWUSR | S_IRUGO, show_fan_max,
  		    set_fan_max, 2);
  static SENSOR_DEVICE_ATTR(fan4_max, S_IWUSR | S_IRUGO, show_fan_max,
  		    set_fan_max, 3);
  
  static SENSOR_DEVICE_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan_min,
  		    set_fan_min, 0);
  static SENSOR_DEVICE_ATTR(fan2_min, S_IWUSR | S_IRUGO, show_fan_min,
  		    set_fan_min, 1);
  static SENSOR_DEVICE_ATTR(fan3_min, S_IWUSR | S_IRUGO, show_fan_min,
  		    set_fan_min, 2);
  static SENSOR_DEVICE_ATTR(fan4_min, S_IWUSR | S_IRUGO, show_fan_min,
  		    set_fan_min, 3);
  
  static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0);
  static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1);
  static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 2);
  static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan, NULL, 3);

  static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_FAN1_ALARM));
  static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_FAN2_ALARM));
  static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_FAN3_ALARM));
  static SENSOR_DEVICE_ATTR(fan4_alarm, S_IRUGO, show_alarm, NULL,
  			  ALARM2(ADT7470_FAN4_ALARM));

  static SENSOR_DEVICE_ATTR(force_pwm_max, S_IWUSR | S_IRUGO,
  		    show_force_pwm_max, set_force_pwm_max, 0);
  
  static SENSOR_DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 0);
  static SENSOR_DEVICE_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 1);
  static SENSOR_DEVICE_ATTR(pwm3, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 2);
  static SENSOR_DEVICE_ATTR(pwm4, S_IWUSR | S_IRUGO, show_pwm, set_pwm, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_auto_point1_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_min, set_pwm_min, 0);
  static SENSOR_DEVICE_ATTR(pwm2_auto_point1_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_min, set_pwm_min, 1);
  static SENSOR_DEVICE_ATTR(pwm3_auto_point1_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_min, set_pwm_min, 2);
  static SENSOR_DEVICE_ATTR(pwm4_auto_point1_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_min, set_pwm_min, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_auto_point2_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_max, set_pwm_max, 0);
  static SENSOR_DEVICE_ATTR(pwm2_auto_point2_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_max, set_pwm_max, 1);
  static SENSOR_DEVICE_ATTR(pwm3_auto_point2_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_max, set_pwm_max, 2);
  static SENSOR_DEVICE_ATTR(pwm4_auto_point2_pwm, S_IWUSR | S_IRUGO,
  		    show_pwm_max, set_pwm_max, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_auto_point1_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_tmin, set_pwm_tmin, 0);
  static SENSOR_DEVICE_ATTR(pwm2_auto_point1_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_tmin, set_pwm_tmin, 1);
  static SENSOR_DEVICE_ATTR(pwm3_auto_point1_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_tmin, set_pwm_tmin, 2);
  static SENSOR_DEVICE_ATTR(pwm4_auto_point1_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_tmin, set_pwm_tmin, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_auto_point2_temp, S_IRUGO, show_pwm_tmax,
  		    NULL, 0);
  static SENSOR_DEVICE_ATTR(pwm2_auto_point2_temp, S_IRUGO, show_pwm_tmax,
  		    NULL, 1);
  static SENSOR_DEVICE_ATTR(pwm3_auto_point2_temp, S_IRUGO, show_pwm_tmax,
  		    NULL, 2);
  static SENSOR_DEVICE_ATTR(pwm4_auto_point2_temp, S_IRUGO, show_pwm_tmax,
  		    NULL, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, show_pwm_auto,
  		    set_pwm_auto, 0);
  static SENSOR_DEVICE_ATTR(pwm2_enable, S_IWUSR | S_IRUGO, show_pwm_auto,
  		    set_pwm_auto, 1);
  static SENSOR_DEVICE_ATTR(pwm3_enable, S_IWUSR | S_IRUGO, show_pwm_auto,
  		    set_pwm_auto, 2);
  static SENSOR_DEVICE_ATTR(pwm4_enable, S_IWUSR | S_IRUGO, show_pwm_auto,
  		    set_pwm_auto, 3);
  
  static SENSOR_DEVICE_ATTR(pwm1_auto_channels_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_auto_temp, set_pwm_auto_temp, 0);
  static SENSOR_DEVICE_ATTR(pwm2_auto_channels_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_auto_temp, set_pwm_auto_temp, 1);
  static SENSOR_DEVICE_ATTR(pwm3_auto_channels_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_auto_temp, set_pwm_auto_temp, 2);
  static SENSOR_DEVICE_ATTR(pwm4_auto_channels_temp, S_IWUSR | S_IRUGO,
  		    show_pwm_auto_temp, set_pwm_auto_temp, 3);
  
  static struct attribute *adt7470_attr[] =
  {

  	&dev_attr_alarm_mask.attr,

  	&dev_attr_num_temp_sensors.attr,

  	&dev_attr_auto_update_interval.attr,

  	&sensor_dev_attr_temp1_max.dev_attr.attr,
  	&sensor_dev_attr_temp2_max.dev_attr.attr,
  	&sensor_dev_attr_temp3_max.dev_attr.attr,
  	&sensor_dev_attr_temp4_max.dev_attr.attr,
  	&sensor_dev_attr_temp5_max.dev_attr.attr,
  	&sensor_dev_attr_temp6_max.dev_attr.attr,
  	&sensor_dev_attr_temp7_max.dev_attr.attr,
  	&sensor_dev_attr_temp8_max.dev_attr.attr,
  	&sensor_dev_attr_temp9_max.dev_attr.attr,
  	&sensor_dev_attr_temp10_max.dev_attr.attr,
  	&sensor_dev_attr_temp1_min.dev_attr.attr,
  	&sensor_dev_attr_temp2_min.dev_attr.attr,
  	&sensor_dev_attr_temp3_min.dev_attr.attr,
  	&sensor_dev_attr_temp4_min.dev_attr.attr,
  	&sensor_dev_attr_temp5_min.dev_attr.attr,
  	&sensor_dev_attr_temp6_min.dev_attr.attr,
  	&sensor_dev_attr_temp7_min.dev_attr.attr,
  	&sensor_dev_attr_temp8_min.dev_attr.attr,
  	&sensor_dev_attr_temp9_min.dev_attr.attr,
  	&sensor_dev_attr_temp10_min.dev_attr.attr,
  	&sensor_dev_attr_temp1_input.dev_attr.attr,
  	&sensor_dev_attr_temp2_input.dev_attr.attr,
  	&sensor_dev_attr_temp3_input.dev_attr.attr,
  	&sensor_dev_attr_temp4_input.dev_attr.attr,
  	&sensor_dev_attr_temp5_input.dev_attr.attr,
  	&sensor_dev_attr_temp6_input.dev_attr.attr,
  	&sensor_dev_attr_temp7_input.dev_attr.attr,
  	&sensor_dev_attr_temp8_input.dev_attr.attr,
  	&sensor_dev_attr_temp9_input.dev_attr.attr,
  	&sensor_dev_attr_temp10_input.dev_attr.attr,

  	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp4_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp5_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp6_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp7_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp8_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp9_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp10_alarm.dev_attr.attr,

  	&sensor_dev_attr_fan1_max.dev_attr.attr,
  	&sensor_dev_attr_fan2_max.dev_attr.attr,
  	&sensor_dev_attr_fan3_max.dev_attr.attr,
  	&sensor_dev_attr_fan4_max.dev_attr.attr,
  	&sensor_dev_attr_fan1_min.dev_attr.attr,
  	&sensor_dev_attr_fan2_min.dev_attr.attr,
  	&sensor_dev_attr_fan3_min.dev_attr.attr,
  	&sensor_dev_attr_fan4_min.dev_attr.attr,
  	&sensor_dev_attr_fan1_input.dev_attr.attr,
  	&sensor_dev_attr_fan2_input.dev_attr.attr,
  	&sensor_dev_attr_fan3_input.dev_attr.attr,
  	&sensor_dev_attr_fan4_input.dev_attr.attr,

  	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
  	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
  	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
  	&sensor_dev_attr_fan4_alarm.dev_attr.attr,

  	&sensor_dev_attr_force_pwm_max.dev_attr.attr,
  	&sensor_dev_attr_pwm1.dev_attr.attr,
  	&sensor_dev_attr_pwm2.dev_attr.attr,
  	&sensor_dev_attr_pwm3.dev_attr.attr,
  	&sensor_dev_attr_pwm4.dev_attr.attr,
  	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm2_auto_point1_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm3_auto_point1_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm4_auto_point1_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm2_auto_point2_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm3_auto_point2_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm4_auto_point2_pwm.dev_attr.attr,
  	&sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm2_auto_point1_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm3_auto_point1_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm4_auto_point1_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm2_auto_point2_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm3_auto_point2_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm4_auto_point2_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
  	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
  	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
  	&sensor_dev_attr_pwm4_enable.dev_attr.attr,
  	&sensor_dev_attr_pwm1_auto_channels_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm2_auto_channels_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm3_auto_channels_temp.dev_attr.attr,
  	&sensor_dev_attr_pwm4_auto_channels_temp.dev_attr.attr,
  	NULL
  };

  /* Return 0 if detection is successful, -ENODEV otherwise */

  static int adt7470_detect(struct i2c_client *client,

  			  struct i2c_board_info *info)

  {

  	struct i2c_adapter *adapter = client->adapter;

  	int vendor, device, revision;

  
  	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))

  		return -ENODEV;

  	vendor = i2c_smbus_read_byte_data(client, ADT7470_REG_VENDOR);
  	if (vendor != ADT7470_VENDOR)
  		return -ENODEV;

  	device = i2c_smbus_read_byte_data(client, ADT7470_REG_DEVICE);
  	if (device != ADT7470_DEVICE)
  		return -ENODEV;

  	revision = i2c_smbus_read_byte_data(client, ADT7470_REG_REVISION);
  	if (revision != ADT7470_REVISION)
  		return -ENODEV;

  	strlcpy(info->type, "adt7470", I2C_NAME_SIZE);

  	return 0;
  }
  
  static int adt7470_probe(struct i2c_client *client,
  			 const struct i2c_device_id *id)
  {
  	struct adt7470_data *data;
  	int err;
  
  	data = kzalloc(sizeof(struct adt7470_data), GFP_KERNEL);
  	if (!data) {
  		err = -ENOMEM;
  		goto exit;
  	}

  	data->num_temp_sensors = -1;

  	data->auto_update_interval = AUTO_UPDATE_INTERVAL;

  	i2c_set_clientdata(client, data);
  	mutex_init(&data->lock);

  
  	dev_info(&client->dev, "%s chip found
  ", client->name);
  
  	/* Initialize the ADT7470 chip */
  	adt7470_init_client(client);
  
  	/* Register sysfs hooks */
  	data->attrs.attrs = adt7470_attr;
  	if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs)))

  		goto exit_free;

  	data->hwmon_dev = hwmon_device_register(&client->dev);
  	if (IS_ERR(data->hwmon_dev)) {
  		err = PTR_ERR(data->hwmon_dev);

  		goto exit_remove;
  	}

  	init_completion(&data->auto_update_stop);
  	data->auto_update = kthread_run(adt7470_update_thread, client,
  					dev_name(data->hwmon_dev));

  	if (IS_ERR(data->auto_update)) {
  		err = PTR_ERR(data->auto_update);

  		goto exit_unregister;

  	}

  	return 0;

  exit_unregister:
  	hwmon_device_unregister(data->hwmon_dev);

  exit_remove:
  	sysfs_remove_group(&client->dev.kobj, &data->attrs);

  exit_free:
  	kfree(data);
  exit:
  	return err;
  }

  static int adt7470_remove(struct i2c_client *client)

  {
  	struct adt7470_data *data = i2c_get_clientdata(client);

  	kthread_stop(data->auto_update);
  	wait_for_completion(&data->auto_update_stop);

  	hwmon_device_unregister(data->hwmon_dev);

  	sysfs_remove_group(&client->dev.kobj, &data->attrs);

  	kfree(data);
  	return 0;
  }
  
  static int __init adt7470_init(void)
  {
  	return i2c_add_driver(&adt7470_driver);
  }
  
  static void __exit adt7470_exit(void)
  {
  	i2c_del_driver(&adt7470_driver);
  }
  
  MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
  MODULE_DESCRIPTION("ADT7470 driver");
  MODULE_LICENSE("GPL");
  
  module_init(adt7470_init);
  module_exit(adt7470_exit);