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Commit 4453d736 authored by Guenter Roeck's avatar Guenter Roeck Committed by Linus Torvalds
Browse files

hwmon: add support for JEDEC JC 42.4 compliant temperature sensors 



[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: default avatarGuenter Roeck <guenter.roeck@ericsson.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 920fa1ff

Documentation/hwmon/jc42

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+97 −0
Original line number Diff line number Diff line 
Kernel driver jc42

==================



Supported chips:

  * Analog Devices ADT7408

    Prefix: 'adt7408'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf

  * IDT TSE2002B3, TS3000B3

    Prefix: 'tse2002b3', 'ts3000b3'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://www.idt.com/products/getdoc.cfm?docid=18715691

	http://www.idt.com/products/getdoc.cfm?docid=18715692

  * Maxim MAX6604

    Prefix: 'max6604'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf

  * Microchip MCP9805, MCP98242, MCP98243, MCP9843

    Prefixes: 'mcp9805', 'mcp98242', 'mcp98243', 'mcp9843'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf

	http://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf

	http://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf

  * NXP Semiconductors SE97, SE97B

    Prefix: 'se97'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://www.nxp.com/documents/data_sheet/SE97.pdf

	http://www.nxp.com/documents/data_sheet/SE97B.pdf

  * NXP Semiconductors SE98

    Prefix: 'se98'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://www.nxp.com/documents/data_sheet/SE98.pdf

  * ON Semiconductor CAT34TS02, CAT6095

    Prefix: 'cat34ts02', 'cat6095'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheet:

	http://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF

	http://www.onsemi.com/pub/Collateral/CAT6095-D.PDF

  * ST Microelectronics STTS424, STTS424E02

    Prefix: 'stts424'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheets:

	http://www.st.com/stonline/products/literature/ds/13447/stts424.pdf

	http://www.st.com/stonline/products/literature/ds/13448/stts424e02.pdf

  * JEDEC JC 42.4 compliant temperature sensor chips

    Prefix: 'jc42'

    Addresses scanned: I2C 0x18 - 0x1f

    Datasheet: -



Author:

	Guenter Roeck <guenter.roeck@ericsson.com>





Description

-----------



This driver implements support for JEDEC JC 42.4 compliant temperature sensors.

The driver auto-detects the chips listed above, but can be manually instantiated

to support other JC 42.4 compliant chips.



Example: the following will load the driver for a generic JC 42.4 compliant

temperature sensor at address 0x18 on I2C bus #1:



# modprobe jc42

# echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device



A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum,

and critical temperature can be configured. There are alarms for high, low,

and critical thresholds.



There is also an hysteresis to control the thresholds for resetting alarms.

Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5,

3.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those

limits. The chip supports only a single register to configure the hysteresis,

which applies to all limits. This register can be written by writing into

temp1_crit_hyst. Other hysteresis attributes are read-only.



Sysfs entries

-------------



temp1_input		Temperature (RO)

temp1_min		Minimum temperature (RW)

temp1_max		Maximum temperature (RW)

temp1_crit		Critical high temperature (RW)



temp1_crit_hyst		Critical hysteresis temperature (RW)

temp1_max_hyst		Maximum hysteresis temperature (RO)



temp1_min_alarm		Temperature low alarm

temp1_max_alarm		Temperature high alarm

temp1_crit_alarm	Temperature critical alarm

MAINTAINERS

+7 −0
Original line number Diff line number Diff line
@@ -3211,6 +3211,13 @@ F: Documentation/video4linux/*.ivtv 
F:	drivers/media/video/ivtv/

F:	include/linux/ivtv*



JC42.4 TEMPERATURE SENSOR DRIVER

M:	Guenter Roeck <linux@roeck-us.net>

L:	lm-sensors@lm-sensors.org

S:	Maintained

F:	drivers/hwmon/jc42.c

F:	Documentation/hwmon/jc42



JFS FILESYSTEM

M:	Dave Kleikamp <shaggy@linux.vnet.ibm.com>

L:	jfs-discussion@lists.sourceforge.net

drivers/hwmon/Kconfig

+11 −0
Original line number Diff line number Diff line
@@ -463,6 +463,17 @@ config SENSORS_JZ4740 
	  This driver can also be build as a module. If so, the module will be

	  called jz4740-hwmon.



config SENSORS_JC42

	tristate "JEDEC JC42.4 compliant temperature sensors"

	help

	  If you say yes here you get support for Jedec JC42.4 compliant

	  temperature sensors. Support will include, but not be limited to,

	  ADT7408, CAT34TS02,, CAT6095, MAX6604, MCP9805, MCP98242, MCP98243,

	  MCP9843, SE97, SE98, STTS424, TSE2002B3, and TS3000B3.



	  This driver can also be built as a module.  If so, the module

	  will be called jc42.



config SENSORS_LM63

	tristate "National Semiconductor LM63 and LM64"

	depends on I2C

drivers/hwmon/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ obj-$(CONFIG_SENSORS_I5K_AMB) += i5k_amb.o 
obj-$(CONFIG_SENSORS_IBMAEM)	+= ibmaem.o

obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o

obj-$(CONFIG_SENSORS_IT87)	+= it87.o

obj-$(CONFIG_SENSORS_JC42)	+= jc42.o

obj-$(CONFIG_SENSORS_JZ4740)	+= jz4740-hwmon.o

obj-$(CONFIG_SENSORS_K8TEMP)	+= k8temp.o

obj-$(CONFIG_SENSORS_K10TEMP)	+= k10temp.o

drivers/hwmon/jc42.c

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+593 −0
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/*

 * jc42.c - driver for Jedec JC42.4 compliant temperature sensors

 *

 * Copyright (c) 2010  Ericsson AB.

 *

 * Derived from lm77.c by Andras BALI <drewie@freemail.hu>.

 *

 * JC42.4 compliant temperature sensors are typically used on memory modules.

 *

 * 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, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, I2C_CLIENT_END };



/* JC42 registers. All registers are 16 bit. */

#define JC42_REG_CAP		0x00

#define JC42_REG_CONFIG		0x01

#define JC42_REG_TEMP_UPPER	0x02

#define JC42_REG_TEMP_LOWER	0x03

#define JC42_REG_TEMP_CRITICAL	0x04

#define JC42_REG_TEMP		0x05

#define JC42_REG_MANID		0x06

#define JC42_REG_DEVICEID	0x07



/* Status bits in temperature register */

#define JC42_ALARM_CRIT_BIT	15

#define JC42_ALARM_MAX_BIT	14

#define JC42_ALARM_MIN_BIT	13



/* Configuration register defines */

#define JC42_CFG_CRIT_ONLY	(1 << 2)

#define JC42_CFG_SHUTDOWN	(1 << 8)

#define JC42_CFG_HYST_SHIFT	9

#define JC42_CFG_HYST_MASK	0x03



/* Capabilities */

#define JC42_CAP_RANGE		(1 << 2)



/* Manufacturer IDs */

#define ADT_MANID		0x11d4  /* Analog Devices */

#define MAX_MANID		0x004d  /* Maxim */

#define IDT_MANID		0x00b3  /* IDT */

#define MCP_MANID		0x0054  /* Microchip */

#define NXP_MANID		0x1131  /* NXP Semiconductors */

#define ONS_MANID		0x1b09  /* ON Semiconductor */

#define STM_MANID		0x104a  /* ST Microelectronics */



/* Supported chips */



/* Analog Devices */

#define ADT7408_DEVID		0x0801

#define ADT7408_DEVID_MASK	0xffff



/* IDT */

#define TS3000B3_DEVID		0x2903  /* Also matches TSE2002B3 */

#define TS3000B3_DEVID_MASK	0xffff



/* Maxim */

#define MAX6604_DEVID		0x3e00

#define MAX6604_DEVID_MASK	0xffff



/* Microchip */

#define MCP98242_DEVID		0x2000

#define MCP98242_DEVID_MASK	0xfffc



#define MCP98243_DEVID		0x2100

#define MCP98243_DEVID_MASK	0xfffc



#define MCP9843_DEVID		0x0000	/* Also matches mcp9805 */

#define MCP9843_DEVID_MASK	0xfffe



/* NXP */

#define SE97_DEVID		0xa200

#define SE97_DEVID_MASK		0xfffc



#define SE98_DEVID		0xa100

#define SE98_DEVID_MASK		0xfffc



/* ON Semiconductor */

#define CAT6095_DEVID		0x0800	/* Also matches CAT34TS02 */

#define CAT6095_DEVID_MASK	0xffe0



/* ST Microelectronics */

#define STTS424_DEVID		0x0101

#define STTS424_DEVID_MASK	0xffff



#define STTS424E_DEVID		0x0000

#define STTS424E_DEVID_MASK	0xfffe



static u16 jc42_hysteresis[] = { 0, 1500, 3000, 6000 };



struct jc42_chips {

	u16 manid;

	u16 devid;

	u16 devid_mask;

};



static struct jc42_chips jc42_chips[] = {

	{ ADT_MANID, ADT7408_DEVID, ADT7408_DEVID_MASK },

	{ IDT_MANID, TS3000B3_DEVID, TS3000B3_DEVID_MASK },

	{ MAX_MANID, MAX6604_DEVID, MAX6604_DEVID_MASK },

	{ MCP_MANID, MCP98242_DEVID, MCP98242_DEVID_MASK },

	{ MCP_MANID, MCP98243_DEVID, MCP98243_DEVID_MASK },

	{ MCP_MANID, MCP9843_DEVID, MCP9843_DEVID_MASK },

	{ NXP_MANID, SE97_DEVID, SE97_DEVID_MASK },

	{ ONS_MANID, CAT6095_DEVID, CAT6095_DEVID_MASK },

	{ NXP_MANID, SE98_DEVID, SE98_DEVID_MASK },

	{ STM_MANID, STTS424_DEVID, STTS424_DEVID_MASK },

	{ STM_MANID, STTS424E_DEVID, STTS424E_DEVID_MASK },

};



/* Each client has this additional data */

struct jc42_data {

	struct device	*hwmon_dev;

	struct mutex	update_lock;	/* protect register access */

	bool		extended;	/* true if extended range supported */

	bool		valid;

	unsigned long	last_updated;	/* In jiffies */

	u16		orig_config;	/* original configuration */

	u16		config;		/* current configuration */

	u16		temp_input;	/* Temperatures */

	u16		temp_crit;

	u16		temp_min;

	u16		temp_max;

};



static int jc42_probe(struct i2c_client *client,

		      const struct i2c_device_id *id);

static int jc42_detect(struct i2c_client *client, struct i2c_board_info *info);

static int jc42_remove(struct i2c_client *client);

static int jc42_read_value(struct i2c_client *client, u8 reg);

static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value);



static struct jc42_data *jc42_update_device(struct device *dev);



static const struct i2c_device_id jc42_id[] = {

	{ "adt7408", 0 },

	{ "cat94ts02", 0 },

	{ "cat6095", 0 },

	{ "jc42", 0 },

	{ "max6604", 0 },

	{ "mcp9805", 0 },

	{ "mcp98242", 0 },

	{ "mcp98243", 0 },

	{ "mcp9843", 0 },

	{ "se97", 0 },

	{ "se97b", 0 },

	{ "se98", 0 },

	{ "stts424", 0 },

	{ "tse2002b3", 0 },

	{ "ts3000b3", 0 },

	{ }

};

MODULE_DEVICE_TABLE(i2c, jc42_id);



#ifdef CONFIG_PM



static int jc42_suspend(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct jc42_data *data = i2c_get_clientdata(client);



	data->config |= JC42_CFG_SHUTDOWN;

	jc42_write_value(client, JC42_REG_CONFIG, data->config);

	return 0;

}



static int jc42_resume(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct jc42_data *data = i2c_get_clientdata(client);



	data->config &= ~JC42_CFG_SHUTDOWN;

	jc42_write_value(client, JC42_REG_CONFIG, data->config);

	return 0;

}



static const struct dev_pm_ops jc42_dev_pm_ops = {

	.suspend = jc42_suspend,

	.resume = jc42_resume,

};



#define JC42_DEV_PM_OPS (&jc42_dev_pm_ops)

#else

#define JC42_DEV_PM_OPS NULL

#endif /* CONFIG_PM */



/* This is the driver that will be inserted */

static struct i2c_driver jc42_driver = {

	.class		= I2C_CLASS_HWMON,

	.driver = {

		.name	= "jc42",

		.pm = JC42_DEV_PM_OPS,

	},

	.probe		= jc42_probe,

	.remove		= jc42_remove,

	.id_table	= jc42_id,

	.detect		= jc42_detect,

	.address_list	= normal_i2c,

};



#define JC42_TEMP_MIN_EXTENDED	(-40000)

#define JC42_TEMP_MIN		0

#define JC42_TEMP_MAX		125000



static u16 jc42_temp_to_reg(int temp, bool extended)

{

	int ntemp = SENSORS_LIMIT(temp,

				  extended ? JC42_TEMP_MIN_EXTENDED :

				  JC42_TEMP_MIN, JC42_TEMP_MAX);



	/* convert from 0.001 to 0.0625 resolution */

	return (ntemp * 2 / 125) & 0x1fff;

}



static int jc42_temp_from_reg(s16 reg)

{

	reg &= 0x1fff;



	/* sign extend register */

	if (reg & 0x1000)

		reg |= 0xf000;



	/* convert from 0.0625 to 0.001 resolution */

	return reg * 125 / 2;

}



/* sysfs stuff */



/* read routines for temperature limits */

#define show(value)	\

static ssize_t show_##value(struct device *dev,				\

			    struct device_attribute *attr,		\

			    char *buf)					\

{									\

	struct jc42_data *data = jc42_update_device(dev);		\

	if (IS_ERR(data))						\

		return PTR_ERR(data);					\

	return sprintf(buf, "%d\n", jc42_temp_from_reg(data->value));	\

}



show(temp_input);

show(temp_crit);

show(temp_min);

show(temp_max);



/* read routines for hysteresis values */

static ssize_t show_temp_crit_hyst(struct device *dev,

				   struct device_attribute *attr, char *buf)

{

	struct jc42_data *data = jc42_update_device(dev);

	int temp, hyst;



	if (IS_ERR(data))

		return PTR_ERR(data);



	temp = jc42_temp_from_reg(data->temp_crit);

	hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)

			       & JC42_CFG_HYST_MASK];

	return sprintf(buf, "%d\n", temp - hyst);

}



static ssize_t show_temp_max_hyst(struct device *dev,

				  struct device_attribute *attr, char *buf)

{

	struct jc42_data *data = jc42_update_device(dev);

	int temp, hyst;



	if (IS_ERR(data))

		return PTR_ERR(data);



	temp = jc42_temp_from_reg(data->temp_max);

	hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)

			       & JC42_CFG_HYST_MASK];

	return sprintf(buf, "%d\n", temp - hyst);

}



/* write routines */

#define set(value, reg)	\

static ssize_t set_##value(struct device *dev,				\

			   struct device_attribute *attr,		\

			   const char *buf, size_t count)		\

{									\

	struct i2c_client *client = to_i2c_client(dev);			\

	struct jc42_data *data = i2c_get_clientdata(client);		\

	int err, ret = count;						\

	long val;							\

	if (strict_strtol(buf, 10, &val) < 0)				\

		return -EINVAL;						\

	mutex_lock(&data->update_lock);					\

	data->value = jc42_temp_to_reg(val, data->extended);		\

	err = jc42_write_value(client, reg, data->value);		\

	if (err < 0)							\

		ret = err;						\

	mutex_unlock(&data->update_lock);				\

	return ret;							\

}



set(temp_min, JC42_REG_TEMP_LOWER);

set(temp_max, JC42_REG_TEMP_UPPER);

set(temp_crit, JC42_REG_TEMP_CRITICAL);



/* JC42.4 compliant chips only support four hysteresis values.

 * Pick best choice and go from there. */

static ssize_t set_temp_crit_hyst(struct device *dev,

				  struct device_attribute *attr,

				  const char *buf, size_t count)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct jc42_data *data = i2c_get_clientdata(client);

	long val;

	int diff, hyst;

	int err;

	int ret = count;



	if (strict_strtoul(buf, 10, &val) < 0)

		return -EINVAL;



	diff = jc42_temp_from_reg(data->temp_crit) - val;

	hyst = 0;

	if (diff > 0) {

		if (diff < 2250)

			hyst = 1;	/* 1.5 degrees C */

		else if (diff < 4500)

			hyst = 2;	/* 3.0 degrees C */

		else

			hyst = 3;	/* 6.0 degrees C */

	}



	mutex_lock(&data->update_lock);

	data->config = (data->config

			& ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT))

	  | (hyst << JC42_CFG_HYST_SHIFT);

	err = jc42_write_value(client, JC42_REG_CONFIG, data->config);

	if (err < 0)

		ret = err;

	mutex_unlock(&data->update_lock);

	return ret;

}



static ssize_t show_alarm(struct device *dev,

			  struct device_attribute *attr, char *buf)

{

	u16 bit = to_sensor_dev_attr(attr)->index;

	struct jc42_data *data = jc42_update_device(dev);

	u16 val;



	if (IS_ERR(data))

		return PTR_ERR(data);



	val = data->temp_input;

	if (bit != JC42_ALARM_CRIT_BIT && (data->config & JC42_CFG_CRIT_ONLY))

		val = 0;

	return sprintf(buf, "%u\n", (val >> bit) & 1);

}



static DEVICE_ATTR(temp1_input, S_IRUGO,

		   show_temp_input, NULL);

static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,

		   show_temp_crit, set_temp_crit);

static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,

		   show_temp_min, set_temp_min);

static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,

		   show_temp_max, set_temp_max);



static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO,

		   show_temp_crit_hyst, set_temp_crit_hyst);

static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,

		   show_temp_max_hyst, NULL);



static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,

			  JC42_ALARM_CRIT_BIT);

static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,

			  JC42_ALARM_MIN_BIT);

static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,

			  JC42_ALARM_MAX_BIT);



static struct attribute *jc42_attributes[] = {

	&dev_attr_temp1_input.attr,

	&dev_attr_temp1_crit.attr,

	&dev_attr_temp1_min.attr,

	&dev_attr_temp1_max.attr,

	&dev_attr_temp1_crit_hyst.attr,

	&dev_attr_temp1_max_hyst.attr,

	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,

	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,

	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,

	NULL

};



static const struct attribute_group jc42_group = {

	.attrs = jc42_attributes,

};



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

static int jc42_detect(struct i2c_client *new_client,

		       struct i2c_board_info *info)

{

	struct i2c_adapter *adapter = new_client->adapter;

	int i, config, cap, manid, devid;



	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |

				     I2C_FUNC_SMBUS_WORD_DATA))

		return -ENODEV;



	cap = jc42_read_value(new_client, JC42_REG_CAP);

	config = jc42_read_value(new_client, JC42_REG_CONFIG);

	manid = jc42_read_value(new_client, JC42_REG_MANID);

	devid = jc42_read_value(new_client, JC42_REG_DEVICEID);



	if (cap < 0 || config < 0 || manid < 0 || devid < 0)

		return -ENODEV;



	if ((cap & 0xff00) || (config & 0xf800))

		return -ENODEV;



	for (i = 0; i < ARRAY_SIZE(jc42_chips); i++) {

		struct jc42_chips *chip = &jc42_chips[i];

		if (manid == chip->manid &&

		    (devid & chip->devid_mask) == chip->devid) {

			strlcpy(info->type, "jc42", I2C_NAME_SIZE);

			return 0;

		}

	}

	return -ENODEV;

}



static int jc42_probe(struct i2c_client *new_client,

		      const struct i2c_device_id *id)

{

	struct jc42_data *data;

	int config, cap, err;



	data = kzalloc(sizeof(struct jc42_data), GFP_KERNEL);

	if (!data) {

		err = -ENOMEM;

		goto exit;

	}



	i2c_set_clientdata(new_client, data);

	mutex_init(&data->update_lock);



	cap = jc42_read_value(new_client, JC42_REG_CAP);

	if (cap < 0) {

		err = -EINVAL;

		goto exit_free;

	}

	data->extended = !!(cap & JC42_CAP_RANGE);



	config = jc42_read_value(new_client, JC42_REG_CONFIG);

	if (config < 0) {

		err = -EINVAL;

		goto exit_free;

	}

	data->orig_config = config;

	if (config & JC42_CFG_SHUTDOWN) {

		config &= ~JC42_CFG_SHUTDOWN;

		jc42_write_value(new_client, JC42_REG_CONFIG, config);

	}

	data->config = config;



	/* Register sysfs hooks */

	err = sysfs_create_group(&new_client->dev.kobj, &jc42_group);

	if (err)

		goto exit_free;



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

	if (IS_ERR(data->hwmon_dev)) {

		err = PTR_ERR(data->hwmon_dev);

		goto exit_remove;

	}



	return 0;



exit_remove:

	sysfs_remove_group(&new_client->dev.kobj, &jc42_group);

exit_free:

	kfree(data);

exit:

	return err;

}



static int jc42_remove(struct i2c_client *client)

{

	struct jc42_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);

	sysfs_remove_group(&client->dev.kobj, &jc42_group);

	if (data->config != data->orig_config)

		jc42_write_value(client, JC42_REG_CONFIG, data->orig_config);

	kfree(data);

	return 0;

}



/* All registers are word-sized. */

static int jc42_read_value(struct i2c_client *client, u8 reg)

{

	int ret = i2c_smbus_read_word_data(client, reg);

	if (ret < 0)

		return ret;

	return swab16(ret);

}



static int jc42_write_value(struct i2c_client *client, u8 reg, u16 value)

{

	return i2c_smbus_write_word_data(client, reg, swab16(value));

}



static struct jc42_data *jc42_update_device(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct jc42_data *data = i2c_get_clientdata(client);

	struct jc42_data *ret = data;

	int val;



	mutex_lock(&data->update_lock);



	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {

		val = jc42_read_value(client, JC42_REG_TEMP);

		if (val < 0) {

			ret = ERR_PTR(val);

			goto abort;

		}

		data->temp_input = val;



		val = jc42_read_value(client, JC42_REG_TEMP_CRITICAL);

		if (val < 0) {

			ret = ERR_PTR(val);

			goto abort;

		}

		data->temp_crit = val;



		val = jc42_read_value(client, JC42_REG_TEMP_LOWER);

		if (val < 0) {

			ret = ERR_PTR(val);

			goto abort;

		}

		data->temp_min = val;



		val = jc42_read_value(client, JC42_REG_TEMP_UPPER);

		if (val < 0) {

			ret = ERR_PTR(val);

			goto abort;

		}

		data->temp_max = val;



		data->last_updated = jiffies;

		data->valid = true;

	}

abort:

	mutex_unlock(&data->update_lock);

	return ret;

}



static int __init sensors_jc42_init(void)

{

	return i2c_add_driver(&jc42_driver);

}



static void __exit sensors_jc42_exit(void)

{

	i2c_del_driver(&jc42_driver);

}



MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");

MODULE_DESCRIPTION("JC42 driver");

MODULE_LICENSE("GPL");



module_init(sensors_jc42_init);

module_exit(sensors_jc42_exit);