/*
   * lm80.c - From lm_sensors, Linux kernel modules for hardware
   * monitoring
   * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
   * and Philip Edelbrock <phil@netroedge.com>
   *
   * Ported to Linux 2.6 by Tiago Sousa <mirage@kaotik.org>
   *
   * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
   */

  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/slab.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>

  
  /* Addresses to scan */

  static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
  						0x2e, 0x2f, I2C_CLIENT_END };

  /* Many LM80 constants specified below */
  
  /* The LM80 registers */
  #define LM80_REG_IN_MAX(nr)		(0x2a + (nr) * 2)
  #define LM80_REG_IN_MIN(nr)		(0x2b + (nr) * 2)
  #define LM80_REG_IN(nr)			(0x20 + (nr))
  
  #define LM80_REG_FAN1			0x28
  #define LM80_REG_FAN2			0x29
  #define LM80_REG_FAN_MIN(nr)		(0x3b + (nr))
  
  #define LM80_REG_TEMP			0x27
  #define LM80_REG_TEMP_HOT_MAX		0x38
  #define LM80_REG_TEMP_HOT_HYST		0x39
  #define LM80_REG_TEMP_OS_MAX		0x3a
  #define LM80_REG_TEMP_OS_HYST		0x3b
  
  #define LM80_REG_CONFIG			0x00
  #define LM80_REG_ALARM1			0x01
  #define LM80_REG_ALARM2			0x02
  #define LM80_REG_MASK1			0x03
  #define LM80_REG_MASK2			0x04
  #define LM80_REG_FANDIV			0x05
  #define LM80_REG_RES			0x06
  
  
  /* Conversions. Rounding and limit checking is only done on the TO_REG
     variants. Note that you should be a bit careful with which arguments
     these macros are called: arguments may be evaluated more than once.
     Fixing this is just not worth it. */

  #define IN_TO_REG(val)		(SENSORS_LIMIT(((val) + 5) / 10, 0, 255))
  #define IN_FROM_REG(val)	((val) * 10)

  
  static inline unsigned char FAN_TO_REG(unsigned rpm, unsigned div)
  {
  	if (rpm == 0)
  		return 255;
  	rpm = SENSORS_LIMIT(rpm, 1, 1000000);

  	return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254);

  }

  #define FAN_FROM_REG(val, div)	((val) == 0 ? -1 : \
  				(val) == 255 ? 0 : 1350000/((div) * (val)))

  
  static inline long TEMP_FROM_REG(u16 temp)
  {
  	long res;
  
  	temp >>= 4;
  	if (temp < 0x0800)
  		res = 625 * (long) temp;
  	else
  		res = ((long) temp - 0x01000) * 625;
  
  	return res / 10;
  }

  #define TEMP_LIMIT_FROM_REG(val)	(((val) > 0x80 ? \
  	(val) - 0x100 : (val)) * 1000)

  #define TEMP_LIMIT_TO_REG(val)		SENSORS_LIMIT((val) < 0 ? \
  	((val) - 500) / 1000 : ((val) + 500) / 1000, 0, 255)

  
  #define DIV_FROM_REG(val)		(1 << (val))
  
  /*
   * Client data (each client gets its own)
   */
  
  struct lm80_data {

  	struct device *hwmon_dev;

  	struct mutex update_lock;

  	char valid;		/* !=0 if following fields are valid */
  	unsigned long last_updated;	/* In jiffies */
  
  	u8 in[7];		/* Register value */
  	u8 in_max[7];		/* Register value */
  	u8 in_min[7];		/* Register value */
  	u8 fan[2];		/* Register value */
  	u8 fan_min[2];		/* Register value */
  	u8 fan_div[2];		/* Register encoding, shifted right */
  	u16 temp;		/* Register values, shifted right */
  	u8 temp_hot_max;	/* Register value */
  	u8 temp_hot_hyst;	/* Register value */
  	u8 temp_os_max;		/* Register value */
  	u8 temp_os_hyst;	/* Register value */
  	u16 alarms;		/* Register encoding, combined */
  };

  /*

   * Functions declaration
   */

  static int lm80_probe(struct i2c_client *client,
  		      const struct i2c_device_id *id);

  static int lm80_detect(struct i2c_client *client, struct i2c_board_info *info);

  static void lm80_init_client(struct i2c_client *client);

  static int lm80_remove(struct i2c_client *client);

  static struct lm80_data *lm80_update_device(struct device *dev);
  static int lm80_read_value(struct i2c_client *client, u8 reg);
  static int lm80_write_value(struct i2c_client *client, u8 reg, u8 value);
  
  /*
   * Driver data (common to all clients)
   */

  static const struct i2c_device_id lm80_id[] = {

  	{ "lm80", 0 },

  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, lm80_id);

  static struct i2c_driver lm80_driver = {

  	.class		= I2C_CLASS_HWMON,

  	.driver = {

  		.name	= "lm80",
  	},

  	.probe		= lm80_probe,
  	.remove		= lm80_remove,
  	.id_table	= lm80_id,
  	.detect		= lm80_detect,

  	.address_list	= normal_i2c,

  };
  
  /*
   * Sysfs stuff
   */
  
  #define show_in(suffix, value) \

  static ssize_t show_in_##suffix(struct device *dev, \
  	struct device_attribute *attr, char *buf) \

  { \

  	int nr = to_sensor_dev_attr(attr)->index; \

  	struct lm80_data *data = lm80_update_device(dev); \

  	return sprintf(buf, "%d
  ", IN_FROM_REG(data->value[nr])); \

  }

  show_in(min, in_min)
  show_in(max, in_max)
  show_in(input, in)

  
  #define set_in(suffix, value, reg) \

  static ssize_t set_in_##suffix(struct device *dev, \
  	struct device_attribute *attr, const char *buf, size_t count) \

  { \

  	int nr = to_sensor_dev_attr(attr)->index; \

  	struct i2c_client *client = to_i2c_client(dev); \
  	struct lm80_data *data = i2c_get_clientdata(client); \
  	long val = simple_strtol(buf, NULL, 10); \

  \

  	mutex_lock(&data->update_lock);\

  	data->value[nr] = IN_TO_REG(val); \
  	lm80_write_value(client, reg(nr), data->value[nr]); \

  	mutex_unlock(&data->update_lock);\

  	return count; \
  }

  set_in(min, in_min, LM80_REG_IN_MIN)
  set_in(max, in_max, LM80_REG_IN_MAX)
  
  #define show_fan(suffix, value) \

  static ssize_t show_fan_##suffix(struct device *dev, \
  	struct device_attribute *attr, char *buf) \

  { \

  	int nr = to_sensor_dev_attr(attr)->index; \

  	struct lm80_data *data = lm80_update_device(dev); \

  	return sprintf(buf, "%d
  ", FAN_FROM_REG(data->value[nr], \
  		       DIV_FROM_REG(data->fan_div[nr]))); \

  }

  show_fan(min, fan_min)
  show_fan(input, fan)

  static ssize_t show_fan_div(struct device *dev, struct device_attribute *attr,
  	char *buf)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct lm80_data *data = lm80_update_device(dev);
  	return sprintf(buf, "%d
  ", DIV_FROM_REG(data->fan_div[nr]));

  }

  static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
  	const char *buf, size_t count)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct i2c_client *client = to_i2c_client(dev);
  	struct lm80_data *data = i2c_get_clientdata(client);
  	long val = simple_strtoul(buf, NULL, 10);
  
  	mutex_lock(&data->update_lock);
  	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
  	lm80_write_value(client, LM80_REG_FAN_MIN(nr + 1), data->fan_min[nr]);
  	mutex_unlock(&data->update_lock);
  	return count;

  }

  
  /* Note: we save and restore the fan minimum here, because its value is
     determined in part by the fan divisor.  This follows the principle of

     least surprise; the user doesn't expect the fan minimum to change just

     because the divisor changed. */

  static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
  	const char *buf, size_t count)

  {

  	int nr = to_sensor_dev_attr(attr)->index;

  	struct i2c_client *client = to_i2c_client(dev);
  	struct lm80_data *data = i2c_get_clientdata(client);
  	unsigned long min, val = simple_strtoul(buf, NULL, 10);
  	u8 reg;
  
  	/* Save fan_min */

  	mutex_lock(&data->update_lock);

  	min = FAN_FROM_REG(data->fan_min[nr],
  			   DIV_FROM_REG(data->fan_div[nr]));
  
  	switch (val) {

  	case 1:
  		data->fan_div[nr] = 0;
  		break;
  	case 2:
  		data->fan_div[nr] = 1;
  		break;
  	case 4:
  		data->fan_div[nr] = 2;
  		break;
  	case 8:
  		data->fan_div[nr] = 3;
  		break;

  	default:
  		dev_err(&client->dev, "fan_div value %ld not "
  			"supported. Choose one of 1, 2, 4 or 8!
  ", val);

  		mutex_unlock(&data->update_lock);

  		return -EINVAL;
  	}
  
  	reg = (lm80_read_value(client, LM80_REG_FANDIV) & ~(3 << (2 * (nr + 1))))
  	    | (data->fan_div[nr] << (2 * (nr + 1)));
  	lm80_write_value(client, LM80_REG_FANDIV, reg);
  
  	/* Restore fan_min */
  	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
  	lm80_write_value(client, LM80_REG_FAN_MIN(nr + 1), data->fan_min[nr]);

  	mutex_unlock(&data->update_lock);

  
  	return count;
  }

  static ssize_t show_temp_input1(struct device *dev,
  	struct device_attribute *attr, char *buf)

  {
  	struct lm80_data *data = lm80_update_device(dev);
  	return sprintf(buf, "%ld
  ", TEMP_FROM_REG(data->temp));
  }
  
  #define show_temp(suffix, value) \

  static ssize_t show_temp_##suffix(struct device *dev, \
  	struct device_attribute *attr, char *buf) \

  { \
  	struct lm80_data *data = lm80_update_device(dev); \
  	return sprintf(buf, "%d
  ", TEMP_LIMIT_FROM_REG(data->value)); \
  }
  show_temp(hot_max, temp_hot_max);
  show_temp(hot_hyst, temp_hot_hyst);
  show_temp(os_max, temp_os_max);
  show_temp(os_hyst, temp_os_hyst);
  
  #define set_temp(suffix, value, reg) \

  static ssize_t set_temp_##suffix(struct device *dev, \
  	struct device_attribute *attr, const char *buf, size_t count) \

  { \
  	struct i2c_client *client = to_i2c_client(dev); \
  	struct lm80_data *data = i2c_get_clientdata(client); \
  	long val = simple_strtoul(buf, NULL, 10); \

  \

  	mutex_lock(&data->update_lock); \

  	data->value = TEMP_LIMIT_TO_REG(val); \
  	lm80_write_value(client, reg, data->value); \

  	mutex_unlock(&data->update_lock); \

  	return count; \
  }
  set_temp(hot_max, temp_hot_max, LM80_REG_TEMP_HOT_MAX);
  set_temp(hot_hyst, temp_hot_hyst, LM80_REG_TEMP_HOT_HYST);
  set_temp(os_max, temp_os_max, LM80_REG_TEMP_OS_MAX);
  set_temp(os_hyst, temp_os_hyst, LM80_REG_TEMP_OS_HYST);

  static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
  			   char *buf)

  {
  	struct lm80_data *data = lm80_update_device(dev);
  	return sprintf(buf, "%u
  ", data->alarms);
  }

  static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
  			  char *buf)
  {
  	int bitnr = to_sensor_dev_attr(attr)->index;
  	struct lm80_data *data = lm80_update_device(dev);
  	return sprintf(buf, "%u
  ", (data->alarms >> bitnr) & 1);
  }

  static SENSOR_DEVICE_ATTR(in0_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 0);
  static SENSOR_DEVICE_ATTR(in1_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 1);
  static SENSOR_DEVICE_ATTR(in2_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 2);
  static SENSOR_DEVICE_ATTR(in3_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 3);
  static SENSOR_DEVICE_ATTR(in4_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 4);
  static SENSOR_DEVICE_ATTR(in5_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 5);
  static SENSOR_DEVICE_ATTR(in6_min, S_IWUSR | S_IRUGO,
  		show_in_min, set_in_min, 6);
  static SENSOR_DEVICE_ATTR(in0_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 0);
  static SENSOR_DEVICE_ATTR(in1_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 1);
  static SENSOR_DEVICE_ATTR(in2_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 2);
  static SENSOR_DEVICE_ATTR(in3_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 3);
  static SENSOR_DEVICE_ATTR(in4_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 4);
  static SENSOR_DEVICE_ATTR(in5_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 5);
  static SENSOR_DEVICE_ATTR(in6_max, S_IWUSR | S_IRUGO,
  		show_in_max, set_in_max, 6);
  static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, show_in_input, NULL, 0);
  static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_in_input, NULL, 1);
  static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_in_input, NULL, 2);
  static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_in_input, NULL, 3);
  static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_in_input, NULL, 4);
  static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, show_in_input, NULL, 5);
  static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, show_in_input, NULL, 6);
  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(fan1_input, S_IRUGO, show_fan_input, NULL, 0);
  static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input, NULL, 1);
  static SENSOR_DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO,
  		show_fan_div, set_fan_div, 0);
  static SENSOR_DEVICE_ATTR(fan2_div, S_IWUSR | S_IRUGO,
  		show_fan_div, set_fan_div, 1);

  static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
  static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_hot_max,

  	set_temp_hot_max);

  static DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, show_temp_hot_hyst,

  	set_temp_hot_hyst);

  static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp_os_max,

  	set_temp_os_max);

  static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp_os_hyst,

  	set_temp_os_hyst);

  static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);

  static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
  static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
  static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
  static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
  static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 4);
  static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 5);
  static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 6);
  static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 10);
  static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 11);
  static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 8);
  static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 13);

  
  /*
   * Real code
   */

  static struct attribute *lm80_attributes[] = {

  	&sensor_dev_attr_in0_min.dev_attr.attr,
  	&sensor_dev_attr_in1_min.dev_attr.attr,
  	&sensor_dev_attr_in2_min.dev_attr.attr,
  	&sensor_dev_attr_in3_min.dev_attr.attr,
  	&sensor_dev_attr_in4_min.dev_attr.attr,
  	&sensor_dev_attr_in5_min.dev_attr.attr,
  	&sensor_dev_attr_in6_min.dev_attr.attr,
  	&sensor_dev_attr_in0_max.dev_attr.attr,
  	&sensor_dev_attr_in1_max.dev_attr.attr,
  	&sensor_dev_attr_in2_max.dev_attr.attr,
  	&sensor_dev_attr_in3_max.dev_attr.attr,
  	&sensor_dev_attr_in4_max.dev_attr.attr,
  	&sensor_dev_attr_in5_max.dev_attr.attr,
  	&sensor_dev_attr_in6_max.dev_attr.attr,
  	&sensor_dev_attr_in0_input.dev_attr.attr,
  	&sensor_dev_attr_in1_input.dev_attr.attr,
  	&sensor_dev_attr_in2_input.dev_attr.attr,
  	&sensor_dev_attr_in3_input.dev_attr.attr,
  	&sensor_dev_attr_in4_input.dev_attr.attr,
  	&sensor_dev_attr_in5_input.dev_attr.attr,
  	&sensor_dev_attr_in6_input.dev_attr.attr,
  	&sensor_dev_attr_fan1_min.dev_attr.attr,
  	&sensor_dev_attr_fan2_min.dev_attr.attr,
  	&sensor_dev_attr_fan1_input.dev_attr.attr,
  	&sensor_dev_attr_fan2_input.dev_attr.attr,
  	&sensor_dev_attr_fan1_div.dev_attr.attr,
  	&sensor_dev_attr_fan2_div.dev_attr.attr,

  	&dev_attr_temp1_input.attr,
  	&dev_attr_temp1_max.attr,
  	&dev_attr_temp1_max_hyst.attr,
  	&dev_attr_temp1_crit.attr,
  	&dev_attr_temp1_crit_hyst.attr,
  	&dev_attr_alarms.attr,

  	&sensor_dev_attr_in0_alarm.dev_attr.attr,
  	&sensor_dev_attr_in1_alarm.dev_attr.attr,
  	&sensor_dev_attr_in2_alarm.dev_attr.attr,
  	&sensor_dev_attr_in3_alarm.dev_attr.attr,
  	&sensor_dev_attr_in4_alarm.dev_attr.attr,
  	&sensor_dev_attr_in5_alarm.dev_attr.attr,
  	&sensor_dev_attr_in6_alarm.dev_attr.attr,
  	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
  	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,

  	NULL
  };
  
  static const struct attribute_group lm80_group = {
  	.attrs = lm80_attributes,
  };

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

  static int lm80_detect(struct i2c_client *client, struct i2c_board_info *info)

  {

  	struct i2c_adapter *adapter = client->adapter;

  	int i, cur;

  
  	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))

  		return -ENODEV;

  
  	/* Now, we do the remaining detection. It is lousy. */

  	if (lm80_read_value(client, LM80_REG_ALARM2) & 0xc0)

  		return -ENODEV;

  	for (i = 0x2a; i <= 0x3d; i++) {

  		cur = i2c_smbus_read_byte_data(client, i);
  		if ((i2c_smbus_read_byte_data(client, i + 0x40) != cur)
  		 || (i2c_smbus_read_byte_data(client, i + 0x80) != cur)
  		 || (i2c_smbus_read_byte_data(client, i + 0xc0) != cur))

  			return -ENODEV;

  	}

  	strlcpy(info->type, "lm80", I2C_NAME_SIZE);

  	return 0;
  }

  static int lm80_probe(struct i2c_client *client,
  		      const struct i2c_device_id *id)
  {
  	struct lm80_data *data;
  	int err;
  
  	data = kzalloc(sizeof(struct lm80_data), GFP_KERNEL);
  	if (!data) {
  		err = -ENOMEM;
  		goto exit;
  	}
  
  	i2c_set_clientdata(client, data);
  	mutex_init(&data->update_lock);

  
  	/* Initialize the LM80 chip */

  	lm80_init_client(client);

  
  	/* A few vars need to be filled upon startup */

  	data->fan_min[0] = lm80_read_value(client, LM80_REG_FAN_MIN(1));
  	data->fan_min[1] = lm80_read_value(client, LM80_REG_FAN_MIN(2));

  
  	/* Register sysfs hooks */

  	err = sysfs_create_group(&client->dev.kobj, &lm80_group);
  	if (err)

  		goto error_free;

  	data->hwmon_dev = hwmon_device_register(&client->dev);

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

  		goto error_remove;

  	}

  	return 0;

  error_remove:

  	sysfs_remove_group(&client->dev.kobj, &lm80_group);

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

  static int lm80_remove(struct i2c_client *client)

  {

  	struct lm80_data *data = i2c_get_clientdata(client);

  	hwmon_device_unregister(data->hwmon_dev);

  	sysfs_remove_group(&client->dev.kobj, &lm80_group);

  	kfree(data);

  	return 0;
  }
  
  static int lm80_read_value(struct i2c_client *client, u8 reg)
  {
  	return i2c_smbus_read_byte_data(client, reg);
  }
  
  static int lm80_write_value(struct i2c_client *client, u8 reg, u8 value)
  {
  	return i2c_smbus_write_byte_data(client, reg, value);
  }
  
  /* Called when we have found a new LM80. */
  static void lm80_init_client(struct i2c_client *client)
  {
  	/* Reset all except Watchdog values and last conversion values
  	   This sets fan-divs to 2, among others. This makes most other
  	   initializations unnecessary */
  	lm80_write_value(client, LM80_REG_CONFIG, 0x80);
  	/* Set 11-bit temperature resolution */
  	lm80_write_value(client, LM80_REG_RES, 0x08);
  
  	/* Start monitoring */
  	lm80_write_value(client, LM80_REG_CONFIG, 0x01);
  }
  
  static struct lm80_data *lm80_update_device(struct device *dev)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct lm80_data *data = i2c_get_clientdata(client);
  	int i;

  	mutex_lock(&data->update_lock);

  
  	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
  		dev_dbg(&client->dev, "Starting lm80 update
  ");
  		for (i = 0; i <= 6; i++) {
  			data->in[i] =
  			    lm80_read_value(client, LM80_REG_IN(i));
  			data->in_min[i] =
  			    lm80_read_value(client, LM80_REG_IN_MIN(i));
  			data->in_max[i] =
  			    lm80_read_value(client, LM80_REG_IN_MAX(i));
  		}
  		data->fan[0] = lm80_read_value(client, LM80_REG_FAN1);
  		data->fan_min[0] =
  		    lm80_read_value(client, LM80_REG_FAN_MIN(1));
  		data->fan[1] = lm80_read_value(client, LM80_REG_FAN2);
  		data->fan_min[1] =
  		    lm80_read_value(client, LM80_REG_FAN_MIN(2));
  
  		data->temp =
  		    (lm80_read_value(client, LM80_REG_TEMP) << 8) |
  		    (lm80_read_value(client, LM80_REG_RES) & 0xf0);
  		data->temp_os_max =
  		    lm80_read_value(client, LM80_REG_TEMP_OS_MAX);
  		data->temp_os_hyst =
  		    lm80_read_value(client, LM80_REG_TEMP_OS_HYST);
  		data->temp_hot_max =
  		    lm80_read_value(client, LM80_REG_TEMP_HOT_MAX);
  		data->temp_hot_hyst =
  		    lm80_read_value(client, LM80_REG_TEMP_HOT_HYST);
  
  		i = lm80_read_value(client, LM80_REG_FANDIV);
  		data->fan_div[0] = (i >> 2) & 0x03;
  		data->fan_div[1] = (i >> 4) & 0x03;
  		data->alarms = lm80_read_value(client, LM80_REG_ALARM1) +
  		    (lm80_read_value(client, LM80_REG_ALARM2) << 8);
  		data->last_updated = jiffies;
  		data->valid = 1;
  	}

  	mutex_unlock(&data->update_lock);

  
  	return data;
  }
  
  static int __init sensors_lm80_init(void)
  {
  	return i2c_add_driver(&lm80_driver);
  }
  
  static void __exit sensors_lm80_exit(void)
  {
  	i2c_del_driver(&lm80_driver);
  }
  
  MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
  	"Philip Edelbrock <phil@netroedge.com>");
  MODULE_DESCRIPTION("LM80 driver");
  MODULE_LICENSE("GPL");
  
  module_init(sensors_lm80_init);
  module_exit(sensors_lm80_exit);