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Commit ba224e2c authored by Jean Delvare's avatar Jean Delvare Committed by Jean Delvare
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hwmon: New PC87427 hardware monitoring driver 



This is a new hardware monitoring driver for the National Semiconductor
PC87427 Super-I/O chip. It only supports fan speed monitoring for now,
while the chip can do much more.

Thanks to Amir Habibi at Candelis for setting up a test system, and to
Michael Kress for testing several iterations of this driver.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent 8e9afcbb

Documentation/hwmon/pc87427

0 → 100644
+38 −0
Original line number Original line Diff line number Diff line 
Kernel driver pc87427

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



Supported chips:

  * National Semiconductor PC87427

    Prefix: 'pc87427'

    Addresses scanned: none, address read from Super I/O config space

    Datasheet: http://www.winbond.com.tw/E-WINBONDHTM/partner/apc_007.html



Author: Jean Delvare <khali@linux-fr.org>



Thanks to Amir Habibi at Candelis for setting up a test system, and to

Michael Kress for testing several iterations of this driver.





Description

-----------



The National Semiconductor Super I/O chip includes complete hardware

monitoring capabilities. It can monitor up to 18 voltages, 8 fans and

6 temperature sensors. Only the fans are supported at the moment.



This chip also has fan controlling features, which are not yet supported

by this driver either.



The driver assumes that no more than one chip is present, which seems

reasonable.





Fan Monitoring

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



Fan rotation speeds are reported as 14-bit values from a gated clock

signal. Speeds down to 83 RPM can be measured.



An alarm is triggered if the rotation speed drops below a programmable

limit. Another alarm is triggered if the speed is too low to to be measured

(including stalled or missing fan).

drivers/hwmon/Kconfig

+13 −0
Original line number Original line Diff line number Diff line
@@ -353,6 +353,19 @@ config SENSORS_PC87360 
	  This driver can also be built as a module.  If so, the module

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

	  will be called pc87360.

	  will be called pc87360.





config SENSORS_PC87427

	tristate "National Semiconductor PC87427"

	depends on HWMON && EXPERIMENTAL

	help

	  If you say yes here you get access to the hardware monitoring

	  functions of the National Semiconductor PC87427 Super-I/O chip.

	  The chip has two distinct logical devices, one for fan speed

	  monitoring and control, and one for voltage and temperature

	  monitoring. Only fan speed monitoring is supported right now.



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

	  will be called pc87427.



config SENSORS_SIS5595

config SENSORS_SIS5595

	tristate "Silicon Integrated Systems Corp. SiS5595"

	tristate "Silicon Integrated Systems Corp. SiS5595"

	depends on HWMON && I2C && PCI && EXPERIMENTAL

	depends on HWMON && I2C && PCI && EXPERIMENTAL

drivers/hwmon/Makefile

+1 −0
Original line number Original line Diff line number Diff line
@@ -41,6 +41,7 @@ obj-$(CONFIG_SENSORS_LM90) += lm90.o 
obj-$(CONFIG_SENSORS_LM92)	+= lm92.o

obj-$(CONFIG_SENSORS_LM92)	+= lm92.o

obj-$(CONFIG_SENSORS_MAX1619)	+= max1619.o

obj-$(CONFIG_SENSORS_MAX1619)	+= max1619.o

obj-$(CONFIG_SENSORS_PC87360)	+= pc87360.o

obj-$(CONFIG_SENSORS_PC87360)	+= pc87360.o

obj-$(CONFIG_SENSORS_PC87427)	+= pc87427.o

obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o

obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o

obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o

obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o

obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o

obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o

drivers/hwmon/pc87427.c

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+627 −0
Original line number Original line Diff line number Diff line 
/*

 *  pc87427.c - hardware monitoring driver for the

 *              National Semiconductor PC87427 Super-I/O chip

 *  Copyright (C) 2006 Jean Delvare <khali@linux-fr.org>

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License version 2 as

 *  published by the Free Software Foundation.

 *

 *  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.

 *

 *  Supports the following chips:

 *

 *  Chip        #vin    #fan    #pwm    #temp   devid

 *  PC87427     -       8       -       -       0xF2

 *

 *  This driver assumes that no more than one chip is present.

 *  Only fan inputs are supported so far, although the chip can do much more.

 */



#include <linux/module.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/jiffies.h>

#include <linux/platform_device.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/err.h>

#include <linux/mutex.h>

#include <linux/sysfs.h>

#include <asm/io.h>



static struct platform_device *pdev;



#define DRVNAME "pc87427"



/* The lock mutex protects both the I/O accesses (needed because the

   device is using banked registers) and the register cache (needed to keep

   the data in the registers and the cache in sync at any time). */

struct pc87427_data {

	struct class_device *class_dev;

	struct mutex lock;

	int address[2];

	const char *name;



	unsigned long last_updated;	/* in jiffies */

	u8 fan_enabled;			/* bit vector */

	u16 fan[8];			/* register values */

	u16 fan_min[8];			/* register values */

	u8 fan_status[8];		/* register values */

};



/*

 * Super-I/O registers and operations

 */



#define SIOREG_LDSEL	0x07	/* Logical device select */

#define SIOREG_DEVID	0x20	/* Device ID */

#define SIOREG_ACT	0x30	/* Device activation */

#define SIOREG_MAP	0x50	/* I/O or memory mapping */

#define SIOREG_IOBASE	0x60	/* I/O base address */



static const u8 logdev[2] = { 0x09, 0x14 };

static const char *logdev_str[2] = { DRVNAME " FMC", DRVNAME " HMC" };

#define LD_FAN		0

#define LD_IN		1

#define LD_TEMP		1



static inline void superio_outb(int sioaddr, int reg, int val)

{

	outb(reg, sioaddr);

	outb(val, sioaddr + 1);

}



static inline int superio_inb(int sioaddr, int reg)

{

	outb(reg, sioaddr);

	return inb(sioaddr + 1);

}



static inline void superio_exit(int sioaddr)

{

	outb(0x02, sioaddr);

	outb(0x02, sioaddr + 1);

}



/*

 * Logical devices

 */



#define REGION_LENGTH		32

#define PC87427_REG_BANK	0x0f

#define BANK_FM(nr)		(nr)

#define BANK_FT(nr)		(0x08 + (nr))

#define BANK_FC(nr)		(0x10 + (nr) * 2)



/*

 * I/O access functions

 */



/* ldi is the logical device index */

static inline int pc87427_read8(struct pc87427_data *data, u8 ldi, u8 reg)

{

	return inb(data->address[ldi] + reg);

}



/* Must be called with data->lock held, except during init */

static inline int pc87427_read8_bank(struct pc87427_data *data, u8 ldi,

				     u8 bank, u8 reg)

{

	outb(bank, data->address[ldi] + PC87427_REG_BANK);

	return inb(data->address[ldi] + reg);

}



/* Must be called with data->lock held, except during init */

static inline void pc87427_write8_bank(struct pc87427_data *data, u8 ldi,

				       u8 bank, u8 reg, u8 value)

{

	outb(bank, data->address[ldi] + PC87427_REG_BANK);

	outb(value, data->address[ldi] + reg);

}



/*

 * Fan registers and conversions

 */



/* fan data registers are 16-bit wide */

#define PC87427_REG_FAN			0x12

#define PC87427_REG_FAN_MIN		0x14

#define PC87427_REG_FAN_STATUS		0x10



#define FAN_STATUS_STALL		(1 << 3)

#define FAN_STATUS_LOSPD		(1 << 1)

#define FAN_STATUS_MONEN		(1 << 0)



/* Dedicated function to read all registers related to a given fan input.

   This saves us quite a few locks and bank selections.

   Must be called with data->lock held.

   nr is from 0 to 7 */

static void pc87427_readall_fan(struct pc87427_data *data, u8 nr)

{

	int iobase = data->address[LD_FAN];



	outb(BANK_FM(nr), iobase + PC87427_REG_BANK);

	data->fan[nr] = inw(iobase + PC87427_REG_FAN);

	data->fan_min[nr] = inw(iobase + PC87427_REG_FAN_MIN);

	data->fan_status[nr] = inb(iobase + PC87427_REG_FAN_STATUS);

	/* Clear fan alarm bits */

	outb(data->fan_status[nr], iobase + PC87427_REG_FAN_STATUS);

}



/* The 2 LSB of fan speed registers are used for something different.

   The actual 2 LSB of the measurements are not available. */

static inline unsigned long fan_from_reg(u16 reg)

{

	reg &= 0xfffc;

	if (reg == 0x0000 || reg == 0xfffc)

		return 0;

	return 5400000UL / reg;

}



/* The 2 LSB of the fan speed limit registers are not significant. */

static inline u16 fan_to_reg(unsigned long val)

{

	if (val < 83UL)

		return 0xffff;

	if (val >= 1350000UL)

		return 0x0004;

	return ((1350000UL + val / 2) / val) << 2;

}



/*

 * Data interface

 */



static struct pc87427_data *pc87427_update_device(struct device *dev)

{

	struct pc87427_data *data = dev_get_drvdata(dev);

	int i;



	mutex_lock(&data->lock);

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

	 && data->last_updated)

		goto done;



	/* Fans */

	for (i = 0; i < 8; i++) {

		if (!(data->fan_enabled & (1 << i)))

			continue;

		pc87427_readall_fan(data, i);

	}

	data->last_updated = jiffies;



done:

	mutex_unlock(&data->lock);

	return data;

}



static ssize_t show_fan_input(struct device *dev, struct device_attribute

			      *devattr, char *buf)

{

	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	struct pc87427_data *data = pc87427_update_device(dev);

	int nr = attr->index;



	return sprintf(buf, "%lu\n", fan_from_reg(data->fan[nr]));

}



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 pc87427_data *data = pc87427_update_device(dev);

	int nr = attr->index;



	return sprintf(buf, "%lu\n", fan_from_reg(data->fan_min[nr]));

}



static ssize_t show_fan_alarm(struct device *dev, struct device_attribute

			      *devattr, char *buf)

{

	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	struct pc87427_data *data = pc87427_update_device(dev);

	int nr = attr->index;



	return sprintf(buf, "%d\n", !!(data->fan_status[nr]

				       & FAN_STATUS_LOSPD));

}



static ssize_t show_fan_fault(struct device *dev, struct device_attribute

			      *devattr, char *buf)

{

	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	struct pc87427_data *data = pc87427_update_device(dev);

	int nr = attr->index;



	return sprintf(buf, "%d\n", !!(data->fan_status[nr]

				       & FAN_STATUS_STALL));

}



static ssize_t set_fan_min(struct device *dev, struct device_attribute

			   *devattr, const char *buf, size_t count)

{

	struct pc87427_data *data = dev_get_drvdata(dev);

	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	int nr = attr->index;

	unsigned long val = simple_strtoul(buf, NULL, 10);

	int iobase = data->address[LD_FAN];



	mutex_lock(&data->lock);

	outb(BANK_FM(nr), iobase + PC87427_REG_BANK);

	/* The low speed limit registers are read-only while monitoring

	   is enabled, so we have to disable monitoring, then change the

	   limit, and finally enable monitoring again. */

	outb(0, iobase + PC87427_REG_FAN_STATUS);

	data->fan_min[nr] = fan_to_reg(val);

	outw(data->fan_min[nr], iobase + PC87427_REG_FAN_MIN);

	outb(FAN_STATUS_MONEN, iobase + PC87427_REG_FAN_STATUS);

	mutex_unlock(&data->lock);



	return count;

}



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(fan3_input, S_IRUGO, show_fan_input, NULL, 2);

static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, show_fan_input, NULL, 3);

static SENSOR_DEVICE_ATTR(fan5_input, S_IRUGO, show_fan_input, NULL, 4);

static SENSOR_DEVICE_ATTR(fan6_input, S_IRUGO, show_fan_input, NULL, 5);

static SENSOR_DEVICE_ATTR(fan7_input, S_IRUGO, show_fan_input, NULL, 6);

static SENSOR_DEVICE_ATTR(fan8_input, S_IRUGO, show_fan_input, NULL, 7);



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(fan5_min, S_IWUSR | S_IRUGO,

			  show_fan_min, set_fan_min, 4);

static SENSOR_DEVICE_ATTR(fan6_min, S_IWUSR | S_IRUGO,

			  show_fan_min, set_fan_min, 5);

static SENSOR_DEVICE_ATTR(fan7_min, S_IWUSR | S_IRUGO,

			  show_fan_min, set_fan_min, 6);

static SENSOR_DEVICE_ATTR(fan8_min, S_IWUSR | S_IRUGO,

			  show_fan_min, set_fan_min, 7);



static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_fan_alarm, NULL, 0);

static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_fan_alarm, NULL, 1);

static SENSOR_DEVICE_ATTR(fan3_alarm, S_IRUGO, show_fan_alarm, NULL, 2);

static SENSOR_DEVICE_ATTR(fan4_alarm, S_IRUGO, show_fan_alarm, NULL, 3);

static SENSOR_DEVICE_ATTR(fan5_alarm, S_IRUGO, show_fan_alarm, NULL, 4);

static SENSOR_DEVICE_ATTR(fan6_alarm, S_IRUGO, show_fan_alarm, NULL, 5);

static SENSOR_DEVICE_ATTR(fan7_alarm, S_IRUGO, show_fan_alarm, NULL, 6);

static SENSOR_DEVICE_ATTR(fan8_alarm, S_IRUGO, show_fan_alarm, NULL, 7);



static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_fan_fault, NULL, 0);

static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_fan_fault, NULL, 1);

static SENSOR_DEVICE_ATTR(fan3_fault, S_IRUGO, show_fan_fault, NULL, 2);

static SENSOR_DEVICE_ATTR(fan4_fault, S_IRUGO, show_fan_fault, NULL, 3);

static SENSOR_DEVICE_ATTR(fan5_fault, S_IRUGO, show_fan_fault, NULL, 4);

static SENSOR_DEVICE_ATTR(fan6_fault, S_IRUGO, show_fan_fault, NULL, 5);

static SENSOR_DEVICE_ATTR(fan7_fault, S_IRUGO, show_fan_fault, NULL, 6);

static SENSOR_DEVICE_ATTR(fan8_fault, S_IRUGO, show_fan_fault, NULL, 7);



static struct attribute *pc87427_attributes_fan[8][5] = {

	{

		&sensor_dev_attr_fan1_input.dev_attr.attr,

		&sensor_dev_attr_fan1_min.dev_attr.attr,

		&sensor_dev_attr_fan1_alarm.dev_attr.attr,

		&sensor_dev_attr_fan1_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan2_input.dev_attr.attr,

		&sensor_dev_attr_fan2_min.dev_attr.attr,

		&sensor_dev_attr_fan2_alarm.dev_attr.attr,

		&sensor_dev_attr_fan2_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan3_input.dev_attr.attr,

		&sensor_dev_attr_fan3_min.dev_attr.attr,

		&sensor_dev_attr_fan3_alarm.dev_attr.attr,

		&sensor_dev_attr_fan3_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan4_input.dev_attr.attr,

		&sensor_dev_attr_fan4_min.dev_attr.attr,

		&sensor_dev_attr_fan4_alarm.dev_attr.attr,

		&sensor_dev_attr_fan4_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan5_input.dev_attr.attr,

		&sensor_dev_attr_fan5_min.dev_attr.attr,

		&sensor_dev_attr_fan5_alarm.dev_attr.attr,

		&sensor_dev_attr_fan5_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan6_input.dev_attr.attr,

		&sensor_dev_attr_fan6_min.dev_attr.attr,

		&sensor_dev_attr_fan6_alarm.dev_attr.attr,

		&sensor_dev_attr_fan6_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan7_input.dev_attr.attr,

		&sensor_dev_attr_fan7_min.dev_attr.attr,

		&sensor_dev_attr_fan7_alarm.dev_attr.attr,

		&sensor_dev_attr_fan7_fault.dev_attr.attr,

		NULL

	}, {

		&sensor_dev_attr_fan8_input.dev_attr.attr,

		&sensor_dev_attr_fan8_min.dev_attr.attr,

		&sensor_dev_attr_fan8_alarm.dev_attr.attr,

		&sensor_dev_attr_fan8_fault.dev_attr.attr,

		NULL

	}

};



static const struct attribute_group pc87427_group_fan[8] = {

	{ .attrs = pc87427_attributes_fan[0] },

	{ .attrs = pc87427_attributes_fan[1] },

	{ .attrs = pc87427_attributes_fan[2] },

	{ .attrs = pc87427_attributes_fan[3] },

	{ .attrs = pc87427_attributes_fan[4] },

	{ .attrs = pc87427_attributes_fan[5] },

	{ .attrs = pc87427_attributes_fan[6] },

	{ .attrs = pc87427_attributes_fan[7] },

};



static ssize_t show_name(struct device *dev, struct device_attribute

			 *devattr, char *buf)

{

	struct pc87427_data *data = dev_get_drvdata(dev);



	return sprintf(buf, "%s\n", data->name);

}

static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);





/*

 * Device detection, attach and detach

 */



static void __devinit pc87427_init_device(struct device *dev)

{

	struct pc87427_data *data = dev_get_drvdata(dev);

	int i;

	u8 reg;



	/* The FMC module should be ready */

	reg = pc87427_read8(data, LD_FAN, PC87427_REG_BANK);

	if (!(reg & 0x80))

		dev_warn(dev, "FMC module not ready!\n");



	/* Check which fans are enabled */

	for (i = 0; i < 8; i++) {

		reg = pc87427_read8_bank(data, LD_FAN, BANK_FM(i),

					 PC87427_REG_FAN_STATUS);

		if (reg & FAN_STATUS_MONEN)

			data->fan_enabled |= (1 << i);

	}



	if (!data->fan_enabled) {

		dev_dbg(dev, "Enabling all fan inputs\n");

		for (i = 0; i < 8; i++)

			pc87427_write8_bank(data, LD_FAN, BANK_FM(i),

					    PC87427_REG_FAN_STATUS,

					    FAN_STATUS_MONEN);

		data->fan_enabled = 0xff;

	}

}



static int __devinit pc87427_probe(struct platform_device *pdev)

{

	struct pc87427_data *data;

	struct resource *res;

	int i, err;



	if (!(data = kzalloc(sizeof(struct pc87427_data), GFP_KERNEL))) {

		err = -ENOMEM;

		printk(KERN_ERR DRVNAME ": Out of memory\n");

		goto exit;

	}



	/* This will need to be revisited when we add support for

	   temperature and voltage monitoring. */

	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

	data->address[0] = res->start;



	mutex_init(&data->lock);

	data->name = "pc87427";

	platform_set_drvdata(pdev, data);

	pc87427_init_device(&pdev->dev);



	/* Register sysfs hooks */

	if ((err = device_create_file(&pdev->dev, &dev_attr_name)))

		goto exit_kfree;

	for (i = 0; i < 8; i++) {

		if (!(data->fan_enabled & (1 << i)))

			continue;

		if ((err = sysfs_create_group(&pdev->dev.kobj,

					      &pc87427_group_fan[i])))

			goto exit_remove_files;

	}



	data->class_dev = hwmon_device_register(&pdev->dev);

	if (IS_ERR(data->class_dev)) {

		err = PTR_ERR(data->class_dev);

		dev_err(&pdev->dev, "Class registration failed (%d)\n", err);

		goto exit_remove_files;

	}



	return 0;



exit_remove_files:

	for (i = 0; i < 8; i++) {

		if (!(data->fan_enabled & (1 << i)))

			continue;

		sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]);

	}

exit_kfree:

	platform_set_drvdata(pdev, NULL);

	kfree(data);

exit:

	return err;

}



static int __devexit pc87427_remove(struct platform_device *pdev)

{

	struct pc87427_data *data = platform_get_drvdata(pdev);

	int i;



	platform_set_drvdata(pdev, NULL);

	hwmon_device_unregister(data->class_dev);

	device_remove_file(&pdev->dev, &dev_attr_name);

	for (i = 0; i < 8; i++) {

		if (!(data->fan_enabled & (1 << i)))

			continue;

		sysfs_remove_group(&pdev->dev.kobj, &pc87427_group_fan[i]);

	}

	kfree(data);



	return 0;

}





static struct platform_driver pc87427_driver = {

	.driver = {

		.owner	= THIS_MODULE,

		.name	= DRVNAME,

	},

	.probe		= pc87427_probe,

	.remove		= __devexit_p(pc87427_remove),

};



static int __init pc87427_device_add(unsigned short address)

{

	struct resource res = {

		.start	= address,

		.end	= address + REGION_LENGTH - 1,

		.name	= logdev_str[0],

		.flags	= IORESOURCE_IO,

	};

	int err;



	pdev = platform_device_alloc(DRVNAME, address);

	if (!pdev) {

		err = -ENOMEM;

		printk(KERN_ERR DRVNAME ": Device allocation failed\n");

		goto exit;

	}



	err = platform_device_add_resources(pdev, &res, 1);

	if (err) {

		printk(KERN_ERR DRVNAME ": Device resource addition failed "

		       "(%d)\n", err);

		goto exit_device_put;

	}



	err = platform_device_add(pdev);

	if (err) {

		printk(KERN_ERR DRVNAME ": Device addition failed (%d)\n",

		       err);

		goto exit_device_put;

	}



	return 0;



exit_device_put:

	platform_device_put(pdev);

exit:

	return err;

}



static int __init pc87427_find(int sioaddr, unsigned short *address)

{

	u16 val;

	int i, err = 0;



	/* Identify device */

	val = superio_inb(sioaddr, SIOREG_DEVID);

	if (val != 0xf2) {	/* PC87427 */

		err = -ENODEV;

		goto exit;

	}



	for (i = 0; i < 2; i++) {

		address[i] = 0;

		/* Select logical device */

		superio_outb(sioaddr, SIOREG_LDSEL, logdev[i]);



		val = superio_inb(sioaddr, SIOREG_ACT);

		if (!(val & 0x01)) {

			printk(KERN_INFO DRVNAME ": Logical device 0x%02x "

			       "not activated\n", logdev[i]);

			continue;

		}



		val = superio_inb(sioaddr, SIOREG_MAP);

		if (val & 0x01) {

			printk(KERN_WARNING DRVNAME ": Logical device 0x%02x "

			       "is memory-mapped, can't use\n", logdev[i]);

			continue;

		}



		val = (superio_inb(sioaddr, SIOREG_IOBASE) << 8)

		    | superio_inb(sioaddr, SIOREG_IOBASE + 1);

		if (!val) {

			printk(KERN_INFO DRVNAME ": I/O base address not set "

			       "for logical device 0x%02x\n", logdev[i]);

			continue;

		}

		address[i] = val;

	}



exit:

	superio_exit(sioaddr);

	return err;

}



static int __init pc87427_init(void)

{

	int err;

	unsigned short address[2];



	if (pc87427_find(0x2e, address)

	 && pc87427_find(0x4e, address))

		return -ENODEV;



	/* For now the driver only handles fans so we only care about the

	   first address. */

	if (!address[0])

		return -ENODEV;



	err = platform_driver_register(&pc87427_driver);

	if (err)

		goto exit;



	/* Sets global pdev as a side effect */

	err = pc87427_device_add(address[0]);

	if (err)

		goto exit_driver;



	return 0;



exit_driver:

	platform_driver_unregister(&pc87427_driver);

exit:

	return err;

}



static void __exit pc87427_exit(void)

{

	platform_device_unregister(pdev);

	platform_driver_unregister(&pc87427_driver);

}



MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");

MODULE_DESCRIPTION("PC87427 hardware monitoring driver");

MODULE_LICENSE("GPL");



module_init(pc87427_init);

module_exit(pc87427_exit);