drivers/hwmon/adm1021.c - pub/scm/linux/kernel/git/ash/linux - Git at Google

 /*
     adm1021.c - Part of lm_sensors, Linux kernel modules for hardware
 		monitoring
     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
     Philip Edelbrock <phil@netroedge.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., 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[] = {
 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };

 enum chips {
 	adm1021, adm1023, max1617, max1617a, thmc10, lm84, gl523sm, mc1066 };

 /* adm1021 constants specified below */

 /* The adm1021 registers */
 /* Read-only */
 /* For nr in 0-1 */
 #define ADM1021_REG_TEMP(nr)		(nr)
 #define ADM1021_REG_STATUS		0x02
 /* 0x41 = AD, 0x49 = TI, 0x4D = Maxim, 0x23 = Genesys , 0x54 = Onsemi */
 #define ADM1021_REG_MAN_ID		0xFE
 /* ADM1021 = 0x0X, ADM1023 = 0x3X */
 #define ADM1021_REG_DEV_ID		0xFF
 /* These use different addresses for reading/writing */
 #define ADM1021_REG_CONFIG_R		0x03
 #define ADM1021_REG_CONFIG_W		0x09
 #define ADM1021_REG_CONV_RATE_R		0x04
 #define ADM1021_REG_CONV_RATE_W		0x0A
 /* These are for the ADM1023's additional precision on the remote temp sensor */
 #define ADM1023_REG_REM_TEMP_PREC	0x10
 #define ADM1023_REG_REM_OFFSET		0x11
 #define ADM1023_REG_REM_OFFSET_PREC	0x12
 #define ADM1023_REG_REM_TOS_PREC	0x13
 #define ADM1023_REG_REM_THYST_PREC	0x14
 /* limits */
 /* For nr in 0-1 */
 #define ADM1021_REG_TOS_R(nr)		(0x05 + 2 * (nr))
 #define ADM1021_REG_TOS_W(nr)		(0x0B + 2 * (nr))
 #define ADM1021_REG_THYST_R(nr)		(0x06 + 2 * (nr))
 #define ADM1021_REG_THYST_W(nr)		(0x0C + 2 * (nr))
 /* write-only */
 #define ADM1021_REG_ONESHOT		0x0F

 /* Initial values */

 /* Note: Even though I left the low and high limits named os and hyst,
 they don't quite work like a thermostat the way the LM75 does.  I.e.,
 a lower temp than THYST actually triggers an alarm instead of
 clearing it.  Weird, ey?   --Phil  */

 /* Each client has this additional data */
 struct adm1021_data {
 	struct device *hwmon_dev;
 	enum chips type;

 	struct mutex update_lock;
 	char valid;		/* !=0 if following fields are valid */
 	char low_power;		/* !=0 if device in low power mode */
 	unsigned long last_updated;	/* In jiffies */

 	int temp_max[2];		/* Register values */
 	int temp_min[2];
 	int temp[2];
 	u8 alarms;
 	/* Special values for ADM1023 only */
 	u8 remote_temp_offset;
 	u8 remote_temp_offset_prec;
 };

 static int adm1021_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id);
 static int adm1021_detect(struct i2c_client *client,
 			  struct i2c_board_info *info);
 static void adm1021_init_client(struct i2c_client *client);
 static int adm1021_remove(struct i2c_client *client);
 static struct adm1021_data *adm1021_update_device(struct device *dev);

 /* (amalysh) read only mode, otherwise any limit's writing confuse BIOS */
 static int read_only;


 static const struct i2c_device_id adm1021_id[] = {
 	{ "adm1021", adm1021 },
 	{ "adm1023", adm1023 },
 	{ "max1617", max1617 },
 	{ "max1617a", max1617a },
 	{ "thmc10", thmc10 },
 	{ "lm84", lm84 },
 	{ "gl523sm", gl523sm },
 	{ "mc1066", mc1066 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adm1021_id);

 /* This is the driver that will be inserted */
 static struct i2c_driver adm1021_driver = {
 	.class		= I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "adm1021",
 	},
 	.probe		= adm1021_probe,
 	.remove		= adm1021_remove,
 	.id_table	= adm1021_id,
 	.detect		= adm1021_detect,
 	.address_list	= normal_i2c,
 };

 static ssize_t show_temp(struct device *dev,
 			 struct device_attribute *devattr, char *buf)
 {
 	int index = to_sensor_dev_attr(devattr)->index;
 	struct adm1021_data *data = adm1021_update_device(dev);

 	return sprintf(buf, "%d\n", data->temp[index]);
 }

 static ssize_t show_temp_max(struct device *dev,
 			     struct device_attribute *devattr, char *buf)
 {
 	int index = to_sensor_dev_attr(devattr)->index;
 	struct adm1021_data *data = adm1021_update_device(dev);

 	return sprintf(buf, "%d\n", data->temp_max[index]);
 }

 static ssize_t show_temp_min(struct device *dev,
 			     struct device_attribute *devattr, char *buf)
 {
 	int index = to_sensor_dev_attr(devattr)->index;
 	struct adm1021_data *data = adm1021_update_device(dev);

 	return sprintf(buf, "%d\n", data->temp_min[index]);
 }

 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
 			  char *buf)
 {
 	int index = to_sensor_dev_attr(attr)->index;
 	struct adm1021_data *data = adm1021_update_device(dev);
 	return sprintf(buf, "%u\n", (data->alarms >> index) & 1);
 }

 static ssize_t show_alarms(struct device *dev,
 			   struct device_attribute *attr,
 			   char *buf)
 {
 	struct adm1021_data *data = adm1021_update_device(dev);
 	return sprintf(buf, "%u\n", data->alarms);
 }

 static ssize_t set_temp_max(struct device *dev,
 			    struct device_attribute *devattr,
 			    const char *buf, size_t count)
 {
 	int index = to_sensor_dev_attr(devattr)->index;
 	struct i2c_client *client = to_i2c_client(dev);
 	struct adm1021_data *data = i2c_get_clientdata(client);
 	long temp = simple_strtol(buf, NULL, 10) / 1000;

 	mutex_lock(&data->update_lock);
 	data->temp_max[index] = SENSORS_LIMIT(temp, -128, 127);
 	if (!read_only)
 		i2c_smbus_write_byte_data(client, ADM1021_REG_TOS_W(index),
 					  data->temp_max[index]);
 	mutex_unlock(&data->update_lock);

 	return count;
 }

 static ssize_t set_temp_min(struct device *dev,
 			    struct device_attribute *devattr,
 			    const char *buf, size_t count)
 {
 	int index = to_sensor_dev_attr(devattr)->index;
 	struct i2c_client *client = to_i2c_client(dev);
 	struct adm1021_data *data = i2c_get_clientdata(client);
 	long temp = simple_strtol(buf, NULL, 10) / 1000;

 	mutex_lock(&data->update_lock);
 	data->temp_min[index] = SENSORS_LIMIT(temp, -128, 127);
 	if (!read_only)
 		i2c_smbus_write_byte_data(client, ADM1021_REG_THYST_W(index),
 					  data->temp_min[index]);
 	mutex_unlock(&data->update_lock);

 	return count;
 }

 static ssize_t show_low_power(struct device *dev,
 			      struct device_attribute *devattr, char *buf)
 {
 	struct adm1021_data *data = adm1021_update_device(dev);
 	return sprintf(buf, "%d\n", data->low_power);
 }

 static ssize_t set_low_power(struct device *dev,
 			     struct device_attribute *devattr,
 			     const char *buf, size_t count)
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	struct adm1021_data *data = i2c_get_clientdata(client);
 	int low_power = simple_strtol(buf, NULL, 10) != 0;

 	mutex_lock(&data->update_lock);
 	if (low_power != data->low_power) {
 		int config = i2c_smbus_read_byte_data(
 			client, ADM1021_REG_CONFIG_R);
 		data->low_power = low_power;
 		i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
 			(config & 0xBF) | (low_power << 6));
 	}
 	mutex_unlock(&data->update_lock);

 	return count;
 }


 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
 			  set_temp_max, 0);
 static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp_min,
 			  set_temp_min, 0);
 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_max,
 			  set_temp_max, 1);
 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_min,
 			  set_temp_min, 1);
 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 5);
 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);

 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 static DEVICE_ATTR(low_power, S_IWUSR | S_IRUGO, show_low_power, set_low_power);

 static struct attribute *adm1021_attributes[] = {
 	&sensor_dev_attr_temp1_max.dev_attr.attr,
 	&sensor_dev_attr_temp1_min.dev_attr.attr,
 	&sensor_dev_attr_temp1_input.dev_attr.attr,
 	&sensor_dev_attr_temp2_max.dev_attr.attr,
 	&sensor_dev_attr_temp2_min.dev_attr.attr,
 	&sensor_dev_attr_temp2_input.dev_attr.attr,
 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
 	&dev_attr_alarms.attr,
 	&dev_attr_low_power.attr,
 	NULL
 };

 static const struct attribute_group adm1021_group = {
 	.attrs = adm1021_attributes,
 };

 /* Return 0 if detection is successful, -ENODEV otherwise */
 static int adm1021_detect(struct i2c_client *client,
 			  struct i2c_board_info *info)
 {
 	struct i2c_adapter *adapter = client->adapter;
 	const char *type_name;
 	int conv_rate, status, config, man_id, dev_id;

 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
 		pr_debug("adm1021: detect failed, "
 			 "smbus byte data not supported!\n");
 		return -ENODEV;
 	}

 	status = i2c_smbus_read_byte_data(client, ADM1021_REG_STATUS);
 	conv_rate = i2c_smbus_read_byte_data(client,
 					     ADM1021_REG_CONV_RATE_R);
 	config = i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R);

 	/* Check unused bits */
 	if ((status & 0x03) || (config & 0x3F) || (conv_rate & 0xF8)) {
 		pr_debug("adm1021: detect failed, chip not detected!\n");
 		return -ENODEV;
 	}

 	/* Determine the chip type. */
 	man_id = i2c_smbus_read_byte_data(client, ADM1021_REG_MAN_ID);
 	dev_id = i2c_smbus_read_byte_data(client, ADM1021_REG_DEV_ID);

 	if (man_id == 0x4d && dev_id == 0x01)
 		type_name = "max1617a";
 	else if (man_id == 0x41) {
 		if ((dev_id & 0xF0) == 0x30)
 			type_name = "adm1023";
 		else
 			type_name = "adm1021";
 	} else if (man_id == 0x49)
 		type_name = "thmc10";
 	else if (man_id == 0x23)
 		type_name = "gl523sm";
 	else if (man_id == 0x54)
 		type_name = "mc1066";
 	/* LM84 Mfr ID in a different place, and it has more unused bits */
 	else if (conv_rate == 0x00
 		 && (config & 0x7F) == 0x00
 		 && (status & 0xAB) == 0x00)
 		type_name = "lm84";
 	else
 		type_name = "max1617";

 	pr_debug("adm1021: Detected chip %s at adapter %d, address 0x%02x.\n",
 		 type_name, i2c_adapter_id(adapter), client->addr);
 	strlcpy(info->type, type_name, I2C_NAME_SIZE);

 	return 0;
 }

 static int adm1021_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
 	struct adm1021_data *data;
 	int err;

 	data = kzalloc(sizeof(struct adm1021_data), GFP_KERNEL);
 	if (!data) {
 		pr_debug("adm1021: detect failed, kzalloc failed!\n");
 		err = -ENOMEM;
 		goto error0;
 	}

 	i2c_set_clientdata(client, data);
 	data->type = id->driver_data;
 	mutex_init(&data->update_lock);

 	/* Initialize the ADM1021 chip */
 	if (data->type != lm84 && !read_only)
 		adm1021_init_client(client);

 	/* Register sysfs hooks */
 	if ((err = sysfs_create_group(&client->dev.kobj, &adm1021_group)))
 		goto error1;

 	data->hwmon_dev = hwmon_device_register(&client->dev);
 	if (IS_ERR(data->hwmon_dev)) {
 		err = PTR_ERR(data->hwmon_dev);
 		goto error3;
 	}

 	return 0;

 error3:
 	sysfs_remove_group(&client->dev.kobj, &adm1021_group);
 error1:
 	kfree(data);
 error0:
 	return err;
 }

 static void adm1021_init_client(struct i2c_client *client)
 {
 	/* Enable ADC and disable suspend mode */
 	i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
 		i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R) & 0xBF);
 	/* Set Conversion rate to 1/sec (this can be tinkered with) */
 	i2c_smbus_write_byte_data(client, ADM1021_REG_CONV_RATE_W, 0x04);
 }

 static int adm1021_remove(struct i2c_client *client)
 {
 	struct adm1021_data *data = i2c_get_clientdata(client);

 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&client->dev.kobj, &adm1021_group);

 	kfree(data);
 	return 0;
 }

 static struct adm1021_data *adm1021_update_device(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
 	struct adm1021_data *data = i2c_get_clientdata(client);

 	mutex_lock(&data->update_lock);

 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
 	    || !data->valid) {
 		int i;

 		dev_dbg(&client->dev, "Starting adm1021 update\n");

 		for (i = 0; i < 2; i++) {
 			data->temp[i] = 1000 *
 				(s8) i2c_smbus_read_byte_data(
 					client, ADM1021_REG_TEMP(i));
 			data->temp_max[i] = 1000 *
 				(s8) i2c_smbus_read_byte_data(
 					client, ADM1021_REG_TOS_R(i));
 			data->temp_min[i] = 1000 *
 				(s8) i2c_smbus_read_byte_data(
 					client, ADM1021_REG_THYST_R(i));
 		}
 		data->alarms = i2c_smbus_read_byte_data(client,
 						ADM1021_REG_STATUS) & 0x7c;
 		if (data->type == adm1023) {
 			/* The ADM1023 provides 3 extra bits of precision for
 			 * the remote sensor in extra registers. */
 			data->temp[1] += 125 * (i2c_smbus_read_byte_data(
 				client, ADM1023_REG_REM_TEMP_PREC) >> 5);
 			data->temp_max[1] += 125 * (i2c_smbus_read_byte_data(
 				client, ADM1023_REG_REM_TOS_PREC) >> 5);
 			data->temp_min[1] += 125 * (i2c_smbus_read_byte_data(
 				client, ADM1023_REG_REM_THYST_PREC) >> 5);
 			data->remote_temp_offset =
 				i2c_smbus_read_byte_data(client,
 						ADM1023_REG_REM_OFFSET);
 			data->remote_temp_offset_prec =
 				i2c_smbus_read_byte_data(client,
 						ADM1023_REG_REM_OFFSET_PREC);
 		}
 		data->last_updated = jiffies;
 		data->valid = 1;
 	}

 	mutex_unlock(&data->update_lock);

 	return data;
 }

 static int __init sensors_adm1021_init(void)
 {
 	return i2c_add_driver(&adm1021_driver);
 }

 static void __exit sensors_adm1021_exit(void)
 {
 	i2c_del_driver(&adm1021_driver);
 }

 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl> and "
 		"Philip Edelbrock <phil@netroedge.com>");
 MODULE_DESCRIPTION("adm1021 driver");
 MODULE_LICENSE("GPL");

 module_param(read_only, bool, 0);
 MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");

 module_init(sensors_adm1021_init)
 module_exit(sensors_adm1021_exit)
	/*
	adm1021.c - Part of lm_sensors, Linux kernel modules for hardware
	monitoring
	Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and
	Philip Edelbrock <phil@netroedge.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., 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[] = {
	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };

	enum chips {
	adm1021, adm1023, max1617, max1617a, thmc10, lm84, gl523sm, mc1066 };

	/* adm1021 constants specified below */

	/* The adm1021 registers */
	/* Read-only */
	/* For nr in 0-1 */
	#define ADM1021_REG_TEMP(nr) (nr)
	#define ADM1021_REG_STATUS 0x02
	/* 0x41 = AD, 0x49 = TI, 0x4D = Maxim, 0x23 = Genesys , 0x54 = Onsemi */
	#define ADM1021_REG_MAN_ID 0xFE
	/* ADM1021 = 0x0X, ADM1023 = 0x3X */
	#define ADM1021_REG_DEV_ID 0xFF
	/* These use different addresses for reading/writing */
	#define ADM1021_REG_CONFIG_R 0x03
	#define ADM1021_REG_CONFIG_W 0x09
	#define ADM1021_REG_CONV_RATE_R 0x04
	#define ADM1021_REG_CONV_RATE_W 0x0A
	/* These are for the ADM1023's additional precision on the remote temp sensor */
	#define ADM1023_REG_REM_TEMP_PREC 0x10
	#define ADM1023_REG_REM_OFFSET 0x11
	#define ADM1023_REG_REM_OFFSET_PREC 0x12
	#define ADM1023_REG_REM_TOS_PREC 0x13
	#define ADM1023_REG_REM_THYST_PREC 0x14
	/* limits */
	/* For nr in 0-1 */
	#define ADM1021_REG_TOS_R(nr) (0x05 + 2 * (nr))
	#define ADM1021_REG_TOS_W(nr) (0x0B + 2 * (nr))
	#define ADM1021_REG_THYST_R(nr) (0x06 + 2 * (nr))
	#define ADM1021_REG_THYST_W(nr) (0x0C + 2 * (nr))
	/* write-only */
	#define ADM1021_REG_ONESHOT 0x0F

	/* Initial values */

	/* Note: Even though I left the low and high limits named os and hyst,
	they don't quite work like a thermostat the way the LM75 does. I.e.,
	a lower temp than THYST actually triggers an alarm instead of
	clearing it. Weird, ey? --Phil */

	/* Each client has this additional data */
	struct adm1021_data {
	struct device *hwmon_dev;
	enum chips type;

	struct mutex update_lock;
	char valid; /* !=0 if following fields are valid */
	char low_power; /* !=0 if device in low power mode */
	unsigned long last_updated; /* In jiffies */

	int temp_max[2]; /* Register values */
	int temp_min[2];
	int temp[2];
	u8 alarms;
	/* Special values for ADM1023 only */
	u8 remote_temp_offset;
	u8 remote_temp_offset_prec;
	};

	static int adm1021_probe(struct i2c_client *client,
	const struct i2c_device_id *id);
	static int adm1021_detect(struct i2c_client *client,
	struct i2c_board_info *info);
	static void adm1021_init_client(struct i2c_client *client);
	static int adm1021_remove(struct i2c_client *client);
	static struct adm1021_data adm1021_update_device(struct device dev);

	/* (amalysh) read only mode, otherwise any limit's writing confuse BIOS */
	static int read_only;


	static const struct i2c_device_id adm1021_id[] = {
	{ "adm1021", adm1021 },
	{ "adm1023", adm1023 },
	{ "max1617", max1617 },
	{ "max1617a", max1617a },
	{ "thmc10", thmc10 },
	{ "lm84", lm84 },
	{ "gl523sm", gl523sm },
	{ "mc1066", mc1066 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, adm1021_id);

	/* This is the driver that will be inserted */
	static struct i2c_driver adm1021_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
	.name = "adm1021",
	},
	.probe = adm1021_probe,
	.remove = adm1021_remove,
	.id_table = adm1021_id,
	.detect = adm1021_detect,
	.address_list = normal_i2c,
	};

	static ssize_t show_temp(struct device *dev,
	struct device_attribute devattr, char buf)
	{
	int index = to_sensor_dev_attr(devattr)->index;
	struct adm1021_data *data = adm1021_update_device(dev);

	return sprintf(buf, "%d\n", data->temp[index]);
	}

	static ssize_t show_temp_max(struct device *dev,
	struct device_attribute devattr, char buf)
	{
	int index = to_sensor_dev_attr(devattr)->index;
	struct adm1021_data *data = adm1021_update_device(dev);

	return sprintf(buf, "%d\n", data->temp_max[index]);
	}

	static ssize_t show_temp_min(struct device *dev,
	struct device_attribute devattr, char buf)
	{
	int index = to_sensor_dev_attr(devattr)->index;
	struct adm1021_data *data = adm1021_update_device(dev);

	return sprintf(buf, "%d\n", data->temp_min[index]);
	}

	static ssize_t show_alarm(struct device dev, struct device_attribute attr,
	char *buf)
	{
	int index = to_sensor_dev_attr(attr)->index;
	struct adm1021_data *data = adm1021_update_device(dev);
	return sprintf(buf, "%u\n", (data->alarms >> index) & 1);
	}

	static ssize_t show_alarms(struct device *dev,
	struct device_attribute *attr,
	char *buf)
	{
	struct adm1021_data *data = adm1021_update_device(dev);
	return sprintf(buf, "%u\n", data->alarms);
	}

	static ssize_t set_temp_max(struct device *dev,
	struct device_attribute *devattr,
	const char *buf, size_t count)
	{
	int index = to_sensor_dev_attr(devattr)->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct adm1021_data *data = i2c_get_clientdata(client);
	long temp = simple_strtol(buf, NULL, 10) / 1000;

	mutex_lock(&data->update_lock);
	data->temp_max[index] = SENSORS_LIMIT(temp, -128, 127);
	if (!read_only)
	i2c_smbus_write_byte_data(client, ADM1021_REG_TOS_W(index),
	data->temp_max[index]);
	mutex_unlock(&data->update_lock);

	return count;
	}

	static ssize_t set_temp_min(struct device *dev,
	struct device_attribute *devattr,
	const char *buf, size_t count)
	{
	int index = to_sensor_dev_attr(devattr)->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct adm1021_data *data = i2c_get_clientdata(client);
	long temp = simple_strtol(buf, NULL, 10) / 1000;

	mutex_lock(&data->update_lock);
	data->temp_min[index] = SENSORS_LIMIT(temp, -128, 127);
	if (!read_only)
	i2c_smbus_write_byte_data(client, ADM1021_REG_THYST_W(index),
	data->temp_min[index]);
	mutex_unlock(&data->update_lock);

	return count;
	}

	static ssize_t show_low_power(struct device *dev,
	struct device_attribute devattr, char buf)
	{
	struct adm1021_data *data = adm1021_update_device(dev);
	return sprintf(buf, "%d\n", data->low_power);
	}

	static ssize_t set_low_power(struct device *dev,
	struct device_attribute *devattr,
	const char *buf, size_t count)
	{
	struct i2c_client *client = to_i2c_client(dev);
	struct adm1021_data *data = i2c_get_clientdata(client);
	int low_power = simple_strtol(buf, NULL, 10) != 0;

	mutex_lock(&data->update_lock);
	if (low_power != data->low_power) {
	int config = i2c_smbus_read_byte_data(
	client, ADM1021_REG_CONFIG_R);
	data->low_power = low_power;
	i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
	(config & 0xBF) \| (low_power << 6));
	}
	mutex_unlock(&data->update_lock);

	return count;
	}


	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
	static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR \| S_IRUGO, show_temp_max,
	set_temp_max, 0);
	static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR \| S_IRUGO, show_temp_min,
	set_temp_min, 0);
	static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
	static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR \| S_IRUGO, show_temp_max,
	set_temp_max, 1);
	static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR \| S_IRUGO, show_temp_min,
	set_temp_min, 1);
	static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
	static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 5);
	static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
	static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
	static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);

	static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
	static DEVICE_ATTR(low_power, S_IWUSR \| S_IRUGO, show_low_power, set_low_power);

	static struct attribute *adm1021_attributes[] = {
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_min.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp2_max.dev_attr.attr,
	&sensor_dev_attr_temp2_min.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_fault.dev_attr.attr,
	&dev_attr_alarms.attr,
	&dev_attr_low_power.attr,
	NULL
	};

	static const struct attribute_group adm1021_group = {
	.attrs = adm1021_attributes,
	};

	/* Return 0 if detection is successful, -ENODEV otherwise */
	static int adm1021_detect(struct i2c_client *client,
	struct i2c_board_info *info)
	{
	struct i2c_adapter *adapter = client->adapter;
	const char *type_name;
	int conv_rate, status, config, man_id, dev_id;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
	pr_debug("adm1021: detect failed, "
	"smbus byte data not supported!\n");
	return -ENODEV;
	}

	status = i2c_smbus_read_byte_data(client, ADM1021_REG_STATUS);
	conv_rate = i2c_smbus_read_byte_data(client,
	ADM1021_REG_CONV_RATE_R);
	config = i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R);

	/* Check unused bits */
	if ((status & 0x03) \|\| (config & 0x3F) \|\| (conv_rate & 0xF8)) {
	pr_debug("adm1021: detect failed, chip not detected!\n");
	return -ENODEV;
	}

	/* Determine the chip type. */
	man_id = i2c_smbus_read_byte_data(client, ADM1021_REG_MAN_ID);
	dev_id = i2c_smbus_read_byte_data(client, ADM1021_REG_DEV_ID);

	if (man_id == 0x4d && dev_id == 0x01)
	type_name = "max1617a";
	else if (man_id == 0x41) {
	if ((dev_id & 0xF0) == 0x30)
	type_name = "adm1023";
	else
	type_name = "adm1021";
	} else if (man_id == 0x49)
	type_name = "thmc10";
	else if (man_id == 0x23)
	type_name = "gl523sm";
	else if (man_id == 0x54)
	type_name = "mc1066";
	/* LM84 Mfr ID in a different place, and it has more unused bits */
	else if (conv_rate == 0x00
	&& (config & 0x7F) == 0x00
	&& (status & 0xAB) == 0x00)
	type_name = "lm84";
	else
	type_name = "max1617";

	pr_debug("adm1021: Detected chip %s at adapter %d, address 0x%02x.\n",
	type_name, i2c_adapter_id(adapter), client->addr);
	strlcpy(info->type, type_name, I2C_NAME_SIZE);

	return 0;
	}

	static int adm1021_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct adm1021_data *data;
	int err;

	data = kzalloc(sizeof(struct adm1021_data), GFP_KERNEL);
	if (!data) {
	pr_debug("adm1021: detect failed, kzalloc failed!\n");
	err = -ENOMEM;
	goto error0;
	}

	i2c_set_clientdata(client, data);
	data->type = id->driver_data;
	mutex_init(&data->update_lock);

	/* Initialize the ADM1021 chip */
	if (data->type != lm84 && !read_only)
	adm1021_init_client(client);

	/* Register sysfs hooks */
	if ((err = sysfs_create_group(&client->dev.kobj, &adm1021_group)))
	goto error1;

	data->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(data->hwmon_dev)) {
	err = PTR_ERR(data->hwmon_dev);
	goto error3;
	}

	return 0;

	error3:
	sysfs_remove_group(&client->dev.kobj, &adm1021_group);
	error1:
	kfree(data);
	error0:
	return err;
	}

	static void adm1021_init_client(struct i2c_client *client)
	{
	/* Enable ADC and disable suspend mode */
	i2c_smbus_write_byte_data(client, ADM1021_REG_CONFIG_W,
	i2c_smbus_read_byte_data(client, ADM1021_REG_CONFIG_R) & 0xBF);
	/* Set Conversion rate to 1/sec (this can be tinkered with) */
	i2c_smbus_write_byte_data(client, ADM1021_REG_CONV_RATE_W, 0x04);
	}

	static int adm1021_remove(struct i2c_client *client)
	{
	struct adm1021_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &adm1021_group);

	kfree(data);
	return 0;
	}

	static struct adm1021_data adm1021_update_device(struct device dev)
	{
	struct i2c_client *client = to_i2c_client(dev);
	struct adm1021_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	\|\| !data->valid) {
	int i;

	dev_dbg(&client->dev, "Starting adm1021 update\n");

	for (i = 0; i < 2; i++) {
	data->temp[i] = 1000 *
	(s8) i2c_smbus_read_byte_data(
	client, ADM1021_REG_TEMP(i));
	data->temp_max[i] = 1000 *
	(s8) i2c_smbus_read_byte_data(
	client, ADM1021_REG_TOS_R(i));
	data->temp_min[i] = 1000 *
	(s8) i2c_smbus_read_byte_data(
	client, ADM1021_REG_THYST_R(i));
	}
	data->alarms = i2c_smbus_read_byte_data(client,
	ADM1021_REG_STATUS) & 0x7c;
	if (data->type == adm1023) {
	/* The ADM1023 provides 3 extra bits of precision for
	* the remote sensor in extra registers. */
	data->temp[1] += 125 * (i2c_smbus_read_byte_data(
	client, ADM1023_REG_REM_TEMP_PREC) >> 5);
	data->temp_max[1] += 125 * (i2c_smbus_read_byte_data(
	client, ADM1023_REG_REM_TOS_PREC) >> 5);
	data->temp_min[1] += 125 * (i2c_smbus_read_byte_data(
	client, ADM1023_REG_REM_THYST_PREC) >> 5);
	data->remote_temp_offset =
	i2c_smbus_read_byte_data(client,
	ADM1023_REG_REM_OFFSET);
	data->remote_temp_offset_prec =
	i2c_smbus_read_byte_data(client,
	ADM1023_REG_REM_OFFSET_PREC);
	}
	data->last_updated = jiffies;
	data->valid = 1;
	}

	mutex_unlock(&data->update_lock);

	return data;
	}

	static int __init sensors_adm1021_init(void)
	{
	return i2c_add_driver(&adm1021_driver);
	}

	static void __exit sensors_adm1021_exit(void)
	{
	i2c_del_driver(&adm1021_driver);
	}

	MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl> and "
	"Philip Edelbrock <phil@netroedge.com>");
	MODULE_DESCRIPTION("adm1021 driver");
	MODULE_LICENSE("GPL");

	module_param(read_only, bool, 0);
	MODULE_PARM_DESC(read_only, "Don't set any values, read only mode");

	module_init(sensors_adm1021_init)
	module_exit(sensors_adm1021_exit)