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/*
* sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc)
*
* Copyright (c) 2002-3 Patrick Mochel
* 2002-3 Open Source Development Lab
*
* This file is released under the GPLv2
*
* This exports a 'system' bus type.
* By default, a 'sys' bus gets added to the root of the system. There will
* always be core system devices. Devices can use sysdev_register() to
* add themselves as children of the system bus.
*/
#include <linux/config.h>
#include <linux/sysdev.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/pm.h>
#include <linux/device.h>
#include <asm/semaphore.h>
#include "base.h"
extern struct subsystem devices_subsys;
#define to_sysdev(k) container_of(k, struct sys_device, kobj)
#define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr)
static ssize_t
sysdev_show(struct kobject * kobj, struct attribute * attr, char * buffer)
{
struct sys_device * sysdev = to_sysdev(kobj);
struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
if (sysdev_attr->show)
return sysdev_attr->show(sysdev, buffer);
return -EIO;
}
static ssize_t
sysdev_store(struct kobject * kobj, struct attribute * attr,
const char * buffer, size_t count)
{
struct sys_device * sysdev = to_sysdev(kobj);
struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
if (sysdev_attr->store)
return sysdev_attr->store(sysdev, buffer, count);
return -EIO;
}
static struct sysfs_ops sysfs_ops = {
.show = sysdev_show,
.store = sysdev_store,
};
static struct kobj_type ktype_sysdev = {
.sysfs_ops = &sysfs_ops,
};
int sysdev_create_file(struct sys_device * s, struct sysdev_attribute * a)
{
return sysfs_create_file(&s->kobj, &a->attr);
}
void sysdev_remove_file(struct sys_device * s, struct sysdev_attribute * a)
{
sysfs_remove_file(&s->kobj, &a->attr);
}
EXPORT_SYMBOL_GPL(sysdev_create_file);
EXPORT_SYMBOL_GPL(sysdev_remove_file);
#define to_sysdev_class(k) container_of(k, struct sysdev_class, kset.kobj)
#define to_sysdev_class_attr(a) container_of(a, \
struct sysdev_class_attribute, attr)
static ssize_t sysdev_class_show(struct kobject *kobj, struct attribute *attr,
char *buffer)
{
struct sysdev_class * class = to_sysdev_class(kobj);
struct sysdev_class_attribute *class_attr = to_sysdev_class_attr(attr);
if (class_attr->show)
return class_attr->show(class, buffer);
return -EIO;
}
static ssize_t sysdev_class_store(struct kobject *kobj, struct attribute *attr,
const char *buffer, size_t count)
{
struct sysdev_class * class = to_sysdev_class(kobj);
struct sysdev_class_attribute * class_attr = to_sysdev_class_attr(attr);
if (class_attr->store)
return class_attr->store(class, buffer, count);
return -EIO;
}
static struct sysfs_ops sysfs_class_ops = {
.show = sysdev_class_show,
.store = sysdev_class_store,
};
static struct kobj_type ktype_sysdev_class = {
.sysfs_ops = &sysfs_class_ops,
};
int sysdev_class_create_file(struct sysdev_class *c,
struct sysdev_class_attribute *a)
{
return sysfs_create_file(&c->kset.kobj, &a->attr);
}
EXPORT_SYMBOL_GPL(sysdev_class_create_file);
void sysdev_class_remove_file(struct sysdev_class *c,
struct sysdev_class_attribute *a)
{
sysfs_remove_file(&c->kset.kobj, &a->attr);
}
EXPORT_SYMBOL_GPL(sysdev_class_remove_file);
/*
* declare system_subsys
*/
static decl_subsys(system, &ktype_sysdev_class, NULL);
int sysdev_class_register(struct sysdev_class * cls)
{
pr_debug("Registering sysdev class '%s'\n",
kobject_name(&cls->kset.kobj));
INIT_LIST_HEAD(&cls->drivers);
cls->kset.subsys = &system_subsys;
kset_set_kset_s(cls, system_subsys);
return kset_register(&cls->kset);
}
void sysdev_class_unregister(struct sysdev_class * cls)
{
pr_debug("Unregistering sysdev class '%s'\n",
kobject_name(&cls->kset.kobj));
kset_unregister(&cls->kset);
}
EXPORT_SYMBOL_GPL(sysdev_class_register);
EXPORT_SYMBOL_GPL(sysdev_class_unregister);
static LIST_HEAD(sysdev_drivers);
static DECLARE_MUTEX(sysdev_drivers_lock);
/**
* sysdev_driver_register - Register auxillary driver
* @cls: Device class driver belongs to.
* @drv: Driver.
*
* If @cls is valid, then @drv is inserted into @cls->drivers to be
* called on each operation on devices of that class. The refcount
* of @cls is incremented.
* Otherwise, @drv is inserted into sysdev_drivers, and called for
* each device.
*/
int sysdev_driver_register(struct sysdev_class * cls,
struct sysdev_driver * drv)
{
down(&sysdev_drivers_lock);
if (cls && kset_get(&cls->kset)) {
list_add_tail(&drv->entry, &cls->drivers);
/* If devices of this class already exist, tell the driver */
if (drv->add) {
struct sys_device *dev;
list_for_each_entry(dev, &cls->kset.list, kobj.entry)
drv->add(dev);
}
} else
list_add_tail(&drv->entry, &sysdev_drivers);
up(&sysdev_drivers_lock);
return 0;
}
/**
* sysdev_driver_unregister - Remove an auxillary driver.
* @cls: Class driver belongs to.
* @drv: Driver.
*/
void sysdev_driver_unregister(struct sysdev_class * cls,
struct sysdev_driver * drv)
{
down(&sysdev_drivers_lock);
list_del_init(&drv->entry);
if (cls) {
if (drv->remove) {
struct sys_device *dev;
list_for_each_entry(dev, &cls->kset.list, kobj.entry)
drv->remove(dev);
}
kset_put(&cls->kset);
}
up(&sysdev_drivers_lock);
}
EXPORT_SYMBOL_GPL(sysdev_driver_register);
EXPORT_SYMBOL_GPL(sysdev_driver_unregister);
/**
* sysdev_register - add a system device to the tree
* @sysdev: device in question
*
*/
int sysdev_register(struct sys_device * sysdev)
{
int error;
struct sysdev_class * cls = sysdev->cls;
if (!cls)
return -EINVAL;
/* Make sure the kset is set */
sysdev->kobj.kset = &cls->kset;
/* But make sure we point to the right type for sysfs translation */
sysdev->kobj.ktype = &ktype_sysdev;
error = kobject_set_name(&sysdev->kobj, "%s%d",
kobject_name(&cls->kset.kobj), sysdev->id);
if (error)
return error;
pr_debug("Registering sys device '%s'\n", kobject_name(&sysdev->kobj));
/* Register the object */
error = kobject_register(&sysdev->kobj);
if (!error) {
struct sysdev_driver * drv;
down(&sysdev_drivers_lock);
/* Generic notification is implicit, because it's that
* code that should have called us.
*/
/* Notify global drivers */
list_for_each_entry(drv, &sysdev_drivers, entry) {
if (drv->add)
drv->add(sysdev);
}
/* Notify class auxillary drivers */
list_for_each_entry(drv, &cls->drivers, entry) {
if (drv->add)
drv->add(sysdev);
}
up(&sysdev_drivers_lock);
}
return error;
}
void sysdev_unregister(struct sys_device * sysdev)
{
struct sysdev_driver * drv;
down(&sysdev_drivers_lock);
list_for_each_entry(drv, &sysdev_drivers, entry) {
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