You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
113 lines
2.6 KiB
113 lines
2.6 KiB
/*
|
|
hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
|
|
|
|
This file defines the sysfs class "hwmon", for use by sensors drivers.
|
|
|
|
Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.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; version 2 of the License.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/kdev_t.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/hwmon.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
#define HWMON_ID_PREFIX "hwmon"
|
|
#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
|
|
|
|
static struct class *hwmon_class;
|
|
|
|
static DEFINE_IDR(hwmon_idr);
|
|
static DEFINE_SPINLOCK(idr_lock);
|
|
|
|
/**
|
|
* hwmon_device_register - register w/ hwmon
|
|
* @dev: the device to register
|
|
*
|
|
* hwmon_device_unregister() must be called when the device is no
|
|
* longer needed.
|
|
*
|
|
* Returns the pointer to the new device.
|
|
*/
|
|
struct device *hwmon_device_register(struct device *dev)
|
|
{
|
|
struct device *hwdev;
|
|
int id, err;
|
|
|
|
again:
|
|
if (unlikely(idr_pre_get(&hwmon_idr, GFP_KERNEL) == 0))
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
spin_lock(&idr_lock);
|
|
err = idr_get_new(&hwmon_idr, NULL, &id);
|
|
spin_unlock(&idr_lock);
|
|
|
|
if (unlikely(err == -EAGAIN))
|
|
goto again;
|
|
else if (unlikely(err))
|
|
return ERR_PTR(err);
|
|
|
|
id = id & MAX_ID_MASK;
|
|
hwdev = device_create(hwmon_class, dev, MKDEV(0, 0), NULL,
|
|
HWMON_ID_FORMAT, id);
|
|
|
|
if (IS_ERR(hwdev)) {
|
|
spin_lock(&idr_lock);
|
|
idr_remove(&hwmon_idr, id);
|
|
spin_unlock(&idr_lock);
|
|
}
|
|
|
|
return hwdev;
|
|
}
|
|
|
|
/**
|
|
* hwmon_device_unregister - removes the previously registered class device
|
|
*
|
|
* @dev: the class device to destroy
|
|
*/
|
|
void hwmon_device_unregister(struct device *dev)
|
|
{
|
|
int id;
|
|
|
|
if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
|
|
device_unregister(dev);
|
|
spin_lock(&idr_lock);
|
|
idr_remove(&hwmon_idr, id);
|
|
spin_unlock(&idr_lock);
|
|
} else
|
|
dev_dbg(dev->parent,
|
|
"hwmon_device_unregister() failed: bad class ID!\n");
|
|
}
|
|
|
|
static int __init hwmon_init(void)
|
|
{
|
|
hwmon_class = class_create(THIS_MODULE, "hwmon");
|
|
if (IS_ERR(hwmon_class)) {
|
|
printk(KERN_ERR "hwmon.c: couldn't create sysfs class\n");
|
|
return PTR_ERR(hwmon_class);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void __exit hwmon_exit(void)
|
|
{
|
|
class_destroy(hwmon_class);
|
|
}
|
|
|
|
subsys_initcall(hwmon_init);
|
|
module_exit(hwmon_exit);
|
|
|
|
EXPORT_SYMBOL_GPL(hwmon_device_register);
|
|
EXPORT_SYMBOL_GPL(hwmon_device_unregister);
|
|
|
|
MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
|
|
MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
|