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authorJean Delvare <khali@linux-fr.org>2006-12-12 18:18:29 +0100
committerJean Delvare <khali@arrakis.delvare>2006-12-12 18:18:29 +0100
commitba224e2c4f0a706714ccb483b0c21d32f5994f67 (patch)
tree572d75a19909ec69a3298135a1646dceffbc584f /drivers/hwmon/pc87427.c
parent8e9afcbbdef71aeeb510732f4f8d5ac3de863df0 (diff)
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: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/hwmon/pc87427.c')
-rw-r--r--drivers/hwmon/pc87427.c627
1 files changed, 627 insertions, 0 deletions
diff --git a/drivers/hwmon/pc87427.c b/drivers/hwmon/pc87427.c
new file mode 100644
index 00000000000..affa21a5ccf
--- /dev/null
+++ b/drivers/hwmon/pc87427.c
@@ -0,0 +1,627 @@
+/*
+ * 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);