![Akinobu Mita](/assets/img/avatar_default.png)
Class virtual directory is created as the need arises. But it is not deleted when the class is unregistered. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
984 lines
24 KiB
C
984 lines
24 KiB
C
/*
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* class.c - basic device class management
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*
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* Copyright (c) 2002-3 Patrick Mochel
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* Copyright (c) 2002-3 Open Source Development Labs
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* Copyright (c) 2003-2004 Greg Kroah-Hartman
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* Copyright (c) 2003-2004 IBM Corp.
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*
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* This file is released under the GPLv2
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*
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*/
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#include <linux/device.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/kdev_t.h>
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#include <linux/err.h>
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#include <linux/slab.h>
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#include "base.h"
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extern struct subsystem devices_subsys;
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#define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
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#define to_class(obj) container_of(obj, struct class, subsys.kset.kobj)
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static ssize_t
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class_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
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{
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struct class_attribute * class_attr = to_class_attr(attr);
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struct class * dc = to_class(kobj);
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ssize_t ret = -EIO;
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if (class_attr->show)
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ret = class_attr->show(dc, buf);
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return ret;
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}
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static ssize_t
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class_attr_store(struct kobject * kobj, struct attribute * attr,
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const char * buf, size_t count)
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{
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struct class_attribute * class_attr = to_class_attr(attr);
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struct class * dc = to_class(kobj);
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ssize_t ret = -EIO;
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if (class_attr->store)
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ret = class_attr->store(dc, buf, count);
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return ret;
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}
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static void class_release(struct kobject * kobj)
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{
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struct class *class = to_class(kobj);
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pr_debug("class '%s': release.\n", class->name);
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if (class->class_release)
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class->class_release(class);
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else
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pr_debug("class '%s' does not have a release() function, "
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"be careful\n", class->name);
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}
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static struct sysfs_ops class_sysfs_ops = {
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.show = class_attr_show,
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.store = class_attr_store,
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};
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static struct kobj_type ktype_class = {
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.sysfs_ops = &class_sysfs_ops,
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.release = class_release,
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};
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/* Hotplug events for classes go to the class_obj subsys */
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static decl_subsys(class, &ktype_class, NULL);
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int class_create_file(struct class * cls, const struct class_attribute * attr)
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{
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int error;
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if (cls) {
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error = sysfs_create_file(&cls->subsys.kset.kobj, &attr->attr);
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} else
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error = -EINVAL;
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return error;
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}
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void class_remove_file(struct class * cls, const struct class_attribute * attr)
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{
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if (cls)
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sysfs_remove_file(&cls->subsys.kset.kobj, &attr->attr);
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}
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static struct class *class_get(struct class *cls)
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{
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if (cls)
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return container_of(subsys_get(&cls->subsys), struct class, subsys);
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return NULL;
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}
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static void class_put(struct class * cls)
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{
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if (cls)
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subsys_put(&cls->subsys);
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}
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static int add_class_attrs(struct class * cls)
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{
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int i;
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int error = 0;
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if (cls->class_attrs) {
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for (i = 0; attr_name(cls->class_attrs[i]); i++) {
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error = class_create_file(cls,&cls->class_attrs[i]);
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if (error)
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goto Err;
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}
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}
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Done:
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return error;
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Err:
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while (--i >= 0)
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class_remove_file(cls,&cls->class_attrs[i]);
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goto Done;
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}
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static void remove_class_attrs(struct class * cls)
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{
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int i;
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if (cls->class_attrs) {
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for (i = 0; attr_name(cls->class_attrs[i]); i++)
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class_remove_file(cls,&cls->class_attrs[i]);
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}
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}
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int class_register(struct class * cls)
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{
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int error;
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pr_debug("device class '%s': registering\n", cls->name);
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INIT_LIST_HEAD(&cls->children);
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INIT_LIST_HEAD(&cls->devices);
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INIT_LIST_HEAD(&cls->interfaces);
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init_MUTEX(&cls->sem);
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error = kobject_set_name(&cls->subsys.kset.kobj, "%s", cls->name);
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if (error)
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return error;
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subsys_set_kset(cls, class_subsys);
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error = subsystem_register(&cls->subsys);
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if (!error) {
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error = add_class_attrs(class_get(cls));
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class_put(cls);
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}
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return error;
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}
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void class_unregister(struct class * cls)
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{
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pr_debug("device class '%s': unregistering\n", cls->name);
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if (cls->virtual_dir)
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kobject_unregister(cls->virtual_dir);
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remove_class_attrs(cls);
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subsystem_unregister(&cls->subsys);
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}
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static void class_create_release(struct class *cls)
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{
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pr_debug("%s called for %s\n", __FUNCTION__, cls->name);
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kfree(cls);
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}
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static void class_device_create_release(struct class_device *class_dev)
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{
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pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
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kfree(class_dev);
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}
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/* needed to allow these devices to have parent class devices */
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static int class_device_create_uevent(struct class_device *class_dev,
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char **envp, int num_envp,
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char *buffer, int buffer_size)
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{
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pr_debug("%s called for %s\n", __FUNCTION__, class_dev->class_id);
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return 0;
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}
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/**
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* class_create - create a struct class structure
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* @owner: pointer to the module that is to "own" this struct class
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* @name: pointer to a string for the name of this class.
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*
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* This is used to create a struct class pointer that can then be used
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* in calls to class_device_create().
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*
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* Note, the pointer created here is to be destroyed when finished by
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* making a call to class_destroy().
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*/
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struct class *class_create(struct module *owner, const char *name)
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{
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struct class *cls;
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int retval;
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cls = kzalloc(sizeof(*cls), GFP_KERNEL);
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if (!cls) {
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retval = -ENOMEM;
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goto error;
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}
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cls->name = name;
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cls->owner = owner;
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cls->class_release = class_create_release;
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cls->release = class_device_create_release;
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retval = class_register(cls);
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if (retval)
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goto error;
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return cls;
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error:
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kfree(cls);
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return ERR_PTR(retval);
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}
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/**
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* class_destroy - destroys a struct class structure
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* @cls: pointer to the struct class that is to be destroyed
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*
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* Note, the pointer to be destroyed must have been created with a call
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* to class_create().
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*/
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void class_destroy(struct class *cls)
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{
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if ((cls == NULL) || (IS_ERR(cls)))
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return;
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class_unregister(cls);
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}
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/* Class Device Stuff */
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int class_device_create_file(struct class_device * class_dev,
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const struct class_device_attribute * attr)
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{
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int error = -EINVAL;
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if (class_dev)
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error = sysfs_create_file(&class_dev->kobj, &attr->attr);
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return error;
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}
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void class_device_remove_file(struct class_device * class_dev,
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const struct class_device_attribute * attr)
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{
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if (class_dev)
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sysfs_remove_file(&class_dev->kobj, &attr->attr);
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}
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int class_device_create_bin_file(struct class_device *class_dev,
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struct bin_attribute *attr)
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{
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int error = -EINVAL;
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if (class_dev)
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error = sysfs_create_bin_file(&class_dev->kobj, attr);
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return error;
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}
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void class_device_remove_bin_file(struct class_device *class_dev,
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struct bin_attribute *attr)
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{
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if (class_dev)
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sysfs_remove_bin_file(&class_dev->kobj, attr);
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}
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static ssize_t
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class_device_attr_show(struct kobject * kobj, struct attribute * attr,
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char * buf)
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{
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struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
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struct class_device * cd = to_class_dev(kobj);
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ssize_t ret = 0;
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if (class_dev_attr->show)
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ret = class_dev_attr->show(cd, buf);
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return ret;
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}
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static ssize_t
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class_device_attr_store(struct kobject * kobj, struct attribute * attr,
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const char * buf, size_t count)
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{
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struct class_device_attribute * class_dev_attr = to_class_dev_attr(attr);
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struct class_device * cd = to_class_dev(kobj);
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ssize_t ret = 0;
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if (class_dev_attr->store)
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ret = class_dev_attr->store(cd, buf, count);
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return ret;
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}
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static struct sysfs_ops class_dev_sysfs_ops = {
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.show = class_device_attr_show,
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.store = class_device_attr_store,
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};
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static void class_dev_release(struct kobject * kobj)
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{
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struct class_device *cd = to_class_dev(kobj);
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struct class * cls = cd->class;
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pr_debug("device class '%s': release.\n", cd->class_id);
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kfree(cd->devt_attr);
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cd->devt_attr = NULL;
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if (cd->release)
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cd->release(cd);
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else if (cls->release)
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cls->release(cd);
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else {
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printk(KERN_ERR "Class Device '%s' does not have a release() function, "
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"it is broken and must be fixed.\n",
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cd->class_id);
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WARN_ON(1);
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}
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}
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static struct kobj_type ktype_class_device = {
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.sysfs_ops = &class_dev_sysfs_ops,
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.release = class_dev_release,
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};
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static int class_uevent_filter(struct kset *kset, struct kobject *kobj)
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{
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struct kobj_type *ktype = get_ktype(kobj);
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if (ktype == &ktype_class_device) {
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struct class_device *class_dev = to_class_dev(kobj);
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if (class_dev->class)
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return 1;
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}
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return 0;
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}
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static const char *class_uevent_name(struct kset *kset, struct kobject *kobj)
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{
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struct class_device *class_dev = to_class_dev(kobj);
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return class_dev->class->name;
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}
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#ifdef CONFIG_SYSFS_DEPRECATED
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char *make_class_name(const char *name, struct kobject *kobj)
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{
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char *class_name;
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int size;
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size = strlen(name) + strlen(kobject_name(kobj)) + 2;
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class_name = kmalloc(size, GFP_KERNEL);
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if (!class_name)
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return ERR_PTR(-ENOMEM);
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strcpy(class_name, name);
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strcat(class_name, ":");
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strcat(class_name, kobject_name(kobj));
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return class_name;
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}
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static int deprecated_class_uevent(char **envp, int num_envp, int *cur_index,
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char *buffer, int buffer_size,
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int *cur_len,
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struct class_device *class_dev)
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{
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struct device *dev = class_dev->dev;
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char *path;
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if (!dev)
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return 0;
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/* add device, backing this class device (deprecated) */
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path = kobject_get_path(&dev->kobj, GFP_KERNEL);
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add_uevent_var(envp, num_envp, cur_index, buffer, buffer_size,
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cur_len, "PHYSDEVPATH=%s", path);
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kfree(path);
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if (dev->bus)
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add_uevent_var(envp, num_envp, cur_index,
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buffer, buffer_size, cur_len,
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"PHYSDEVBUS=%s", dev->bus->name);
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if (dev->driver)
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add_uevent_var(envp, num_envp, cur_index,
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buffer, buffer_size, cur_len,
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"PHYSDEVDRIVER=%s", dev->driver->name);
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return 0;
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}
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static int make_deprecated_class_device_links(struct class_device *class_dev)
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{
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char *class_name;
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int error;
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if (!class_dev->dev)
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return 0;
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class_name = make_class_name(class_dev->class->name, &class_dev->kobj);
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error = sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
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class_name);
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kfree(class_name);
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return error;
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}
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static void remove_deprecated_class_device_links(struct class_device *class_dev)
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{
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char *class_name;
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if (!class_dev->dev)
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return;
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class_name = make_class_name(class_dev->class->name, &class_dev->kobj);
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sysfs_remove_link(&class_dev->dev->kobj, class_name);
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kfree(class_name);
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}
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#else
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static inline int deprecated_class_uevent(char **envp, int num_envp,
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int *cur_index, char *buffer,
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int buffer_size, int *cur_len,
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struct class_device *class_dev)
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{ return 0; }
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static inline int make_deprecated_class_device_links(struct class_device *cd)
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{ return 0; }
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static void remove_deprecated_class_device_links(struct class_device *cd)
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{ }
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#endif
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static int class_uevent(struct kset *kset, struct kobject *kobj, char **envp,
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int num_envp, char *buffer, int buffer_size)
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{
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struct class_device *class_dev = to_class_dev(kobj);
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int i = 0;
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int length = 0;
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int retval = 0;
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pr_debug("%s - name = %s\n", __FUNCTION__, class_dev->class_id);
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deprecated_class_uevent(envp, num_envp, &i, buffer, buffer_size,
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&length, class_dev);
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if (MAJOR(class_dev->devt)) {
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add_uevent_var(envp, num_envp, &i,
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buffer, buffer_size, &length,
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"MAJOR=%u", MAJOR(class_dev->devt));
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add_uevent_var(envp, num_envp, &i,
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buffer, buffer_size, &length,
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"MINOR=%u", MINOR(class_dev->devt));
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}
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|
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/* terminate, set to next free slot, shrink available space */
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envp[i] = NULL;
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envp = &envp[i];
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num_envp -= i;
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buffer = &buffer[length];
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buffer_size -= length;
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|
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if (class_dev->uevent) {
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/* have the class device specific function add its stuff */
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retval = class_dev->uevent(class_dev, envp, num_envp,
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buffer, buffer_size);
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if (retval)
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pr_debug("class_dev->uevent() returned %d\n", retval);
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} else if (class_dev->class->uevent) {
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/* have the class specific function add its stuff */
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retval = class_dev->class->uevent(class_dev, envp, num_envp,
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buffer, buffer_size);
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if (retval)
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pr_debug("class->uevent() returned %d\n", retval);
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}
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return retval;
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}
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|
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static struct kset_uevent_ops class_uevent_ops = {
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.filter = class_uevent_filter,
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.name = class_uevent_name,
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.uevent = class_uevent,
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};
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|
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static decl_subsys(class_obj, &ktype_class_device, &class_uevent_ops);
|
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|
|
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static int class_device_add_attrs(struct class_device * cd)
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{
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int i;
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int error = 0;
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struct class * cls = cd->class;
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|
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if (cls->class_dev_attrs) {
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for (i = 0; attr_name(cls->class_dev_attrs[i]); i++) {
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error = class_device_create_file(cd,
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&cls->class_dev_attrs[i]);
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if (error)
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goto Err;
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}
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}
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Done:
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return error;
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Err:
|
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while (--i >= 0)
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class_device_remove_file(cd,&cls->class_dev_attrs[i]);
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goto Done;
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}
|
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|
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static void class_device_remove_attrs(struct class_device * cd)
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{
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int i;
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struct class * cls = cd->class;
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|
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if (cls->class_dev_attrs) {
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for (i = 0; attr_name(cls->class_dev_attrs[i]); i++)
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class_device_remove_file(cd,&cls->class_dev_attrs[i]);
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}
|
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}
|
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|
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static int class_device_add_groups(struct class_device * cd)
|
|
{
|
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int i;
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int error = 0;
|
|
|
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if (cd->groups) {
|
|
for (i = 0; cd->groups[i]; i++) {
|
|
error = sysfs_create_group(&cd->kobj, cd->groups[i]);
|
|
if (error) {
|
|
while (--i >= 0)
|
|
sysfs_remove_group(&cd->kobj, cd->groups[i]);
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static void class_device_remove_groups(struct class_device * cd)
|
|
{
|
|
int i;
|
|
if (cd->groups) {
|
|
for (i = 0; cd->groups[i]; i++) {
|
|
sysfs_remove_group(&cd->kobj, cd->groups[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
static ssize_t show_dev(struct class_device *class_dev, char *buf)
|
|
{
|
|
return print_dev_t(buf, class_dev->devt);
|
|
}
|
|
|
|
static ssize_t store_uevent(struct class_device *class_dev,
|
|
const char *buf, size_t count)
|
|
{
|
|
kobject_uevent(&class_dev->kobj, KOBJ_ADD);
|
|
return count;
|
|
}
|
|
|
|
void class_device_initialize(struct class_device *class_dev)
|
|
{
|
|
kobj_set_kset_s(class_dev, class_obj_subsys);
|
|
kobject_init(&class_dev->kobj);
|
|
INIT_LIST_HEAD(&class_dev->node);
|
|
}
|
|
|
|
int class_device_add(struct class_device *class_dev)
|
|
{
|
|
struct class *parent_class = NULL;
|
|
struct class_device *parent_class_dev = NULL;
|
|
struct class_interface *class_intf;
|
|
int error = -EINVAL;
|
|
|
|
class_dev = class_device_get(class_dev);
|
|
if (!class_dev)
|
|
return -EINVAL;
|
|
|
|
if (!strlen(class_dev->class_id))
|
|
goto out1;
|
|
|
|
parent_class = class_get(class_dev->class);
|
|
if (!parent_class)
|
|
goto out1;
|
|
|
|
parent_class_dev = class_device_get(class_dev->parent);
|
|
|
|
pr_debug("CLASS: registering class device: ID = '%s'\n",
|
|
class_dev->class_id);
|
|
|
|
/* first, register with generic layer. */
|
|
error = kobject_set_name(&class_dev->kobj, "%s", class_dev->class_id);
|
|
if (error)
|
|
goto out2;
|
|
|
|
if (parent_class_dev)
|
|
class_dev->kobj.parent = &parent_class_dev->kobj;
|
|
else
|
|
class_dev->kobj.parent = &parent_class->subsys.kset.kobj;
|
|
|
|
error = kobject_add(&class_dev->kobj);
|
|
if (error)
|
|
goto out2;
|
|
|
|
/* add the needed attributes to this device */
|
|
error = sysfs_create_link(&class_dev->kobj,
|
|
&parent_class->subsys.kset.kobj, "subsystem");
|
|
if (error)
|
|
goto out3;
|
|
class_dev->uevent_attr.attr.name = "uevent";
|
|
class_dev->uevent_attr.attr.mode = S_IWUSR;
|
|
class_dev->uevent_attr.attr.owner = parent_class->owner;
|
|
class_dev->uevent_attr.store = store_uevent;
|
|
error = class_device_create_file(class_dev, &class_dev->uevent_attr);
|
|
if (error)
|
|
goto out3;
|
|
|
|
if (MAJOR(class_dev->devt)) {
|
|
struct class_device_attribute *attr;
|
|
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
|
|
if (!attr) {
|
|
error = -ENOMEM;
|
|
goto out4;
|
|
}
|
|
attr->attr.name = "dev";
|
|
attr->attr.mode = S_IRUGO;
|
|
attr->attr.owner = parent_class->owner;
|
|
attr->show = show_dev;
|
|
error = class_device_create_file(class_dev, attr);
|
|
if (error) {
|
|
kfree(attr);
|
|
goto out4;
|
|
}
|
|
|
|
class_dev->devt_attr = attr;
|
|
}
|
|
|
|
error = class_device_add_attrs(class_dev);
|
|
if (error)
|
|
goto out5;
|
|
|
|
if (class_dev->dev) {
|
|
error = sysfs_create_link(&class_dev->kobj,
|
|
&class_dev->dev->kobj, "device");
|
|
if (error)
|
|
goto out6;
|
|
}
|
|
|
|
error = class_device_add_groups(class_dev);
|
|
if (error)
|
|
goto out7;
|
|
|
|
error = make_deprecated_class_device_links(class_dev);
|
|
if (error)
|
|
goto out8;
|
|
|
|
kobject_uevent(&class_dev->kobj, KOBJ_ADD);
|
|
|
|
/* notify any interfaces this device is now here */
|
|
down(&parent_class->sem);
|
|
list_add_tail(&class_dev->node, &parent_class->children);
|
|
list_for_each_entry(class_intf, &parent_class->interfaces, node) {
|
|
if (class_intf->add)
|
|
class_intf->add(class_dev, class_intf);
|
|
}
|
|
up(&parent_class->sem);
|
|
|
|
goto out1;
|
|
|
|
out8:
|
|
class_device_remove_groups(class_dev);
|
|
out7:
|
|
if (class_dev->dev)
|
|
sysfs_remove_link(&class_dev->kobj, "device");
|
|
out6:
|
|
class_device_remove_attrs(class_dev);
|
|
out5:
|
|
if (class_dev->devt_attr)
|
|
class_device_remove_file(class_dev, class_dev->devt_attr);
|
|
out4:
|
|
class_device_remove_file(class_dev, &class_dev->uevent_attr);
|
|
out3:
|
|
kobject_del(&class_dev->kobj);
|
|
out2:
|
|
if(parent_class_dev)
|
|
class_device_put(parent_class_dev);
|
|
class_put(parent_class);
|
|
out1:
|
|
class_device_put(class_dev);
|
|
return error;
|
|
}
|
|
|
|
int class_device_register(struct class_device *class_dev)
|
|
{
|
|
class_device_initialize(class_dev);
|
|
return class_device_add(class_dev);
|
|
}
|
|
|
|
/**
|
|
* class_device_create - creates a class device and registers it with sysfs
|
|
* @cls: pointer to the struct class that this device should be registered to.
|
|
* @parent: pointer to the parent struct class_device of this new device, if any.
|
|
* @devt: the dev_t for the char device to be added.
|
|
* @device: a pointer to a struct device that is assiociated with this class device.
|
|
* @fmt: string for the class device's name
|
|
*
|
|
* This function can be used by char device classes. A struct
|
|
* class_device will be created in sysfs, registered to the specified
|
|
* class.
|
|
* A "dev" file will be created, showing the dev_t for the device, if
|
|
* the dev_t is not 0,0.
|
|
* If a pointer to a parent struct class_device is passed in, the newly
|
|
* created struct class_device will be a child of that device in sysfs.
|
|
* The pointer to the struct class_device will be returned from the
|
|
* call. Any further sysfs files that might be required can be created
|
|
* using this pointer.
|
|
*
|
|
* Note: the struct class passed to this function must have previously
|
|
* been created with a call to class_create().
|
|
*/
|
|
struct class_device *class_device_create(struct class *cls,
|
|
struct class_device *parent,
|
|
dev_t devt,
|
|
struct device *device,
|
|
const char *fmt, ...)
|
|
{
|
|
va_list args;
|
|
struct class_device *class_dev = NULL;
|
|
int retval = -ENODEV;
|
|
|
|
if (cls == NULL || IS_ERR(cls))
|
|
goto error;
|
|
|
|
class_dev = kzalloc(sizeof(*class_dev), GFP_KERNEL);
|
|
if (!class_dev) {
|
|
retval = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
class_dev->devt = devt;
|
|
class_dev->dev = device;
|
|
class_dev->class = cls;
|
|
class_dev->parent = parent;
|
|
class_dev->release = class_device_create_release;
|
|
class_dev->uevent = class_device_create_uevent;
|
|
|
|
va_start(args, fmt);
|
|
vsnprintf(class_dev->class_id, BUS_ID_SIZE, fmt, args);
|
|
va_end(args);
|
|
retval = class_device_register(class_dev);
|
|
if (retval)
|
|
goto error;
|
|
|
|
return class_dev;
|
|
|
|
error:
|
|
kfree(class_dev);
|
|
return ERR_PTR(retval);
|
|
}
|
|
|
|
void class_device_del(struct class_device *class_dev)
|
|
{
|
|
struct class *parent_class = class_dev->class;
|
|
struct class_device *parent_device = class_dev->parent;
|
|
struct class_interface *class_intf;
|
|
|
|
if (parent_class) {
|
|
down(&parent_class->sem);
|
|
list_del_init(&class_dev->node);
|
|
list_for_each_entry(class_intf, &parent_class->interfaces, node)
|
|
if (class_intf->remove)
|
|
class_intf->remove(class_dev, class_intf);
|
|
up(&parent_class->sem);
|
|
}
|
|
|
|
if (class_dev->dev) {
|
|
remove_deprecated_class_device_links(class_dev);
|
|
sysfs_remove_link(&class_dev->kobj, "device");
|
|
}
|
|
sysfs_remove_link(&class_dev->kobj, "subsystem");
|
|
class_device_remove_file(class_dev, &class_dev->uevent_attr);
|
|
if (class_dev->devt_attr)
|
|
class_device_remove_file(class_dev, class_dev->devt_attr);
|
|
class_device_remove_attrs(class_dev);
|
|
class_device_remove_groups(class_dev);
|
|
|
|
kobject_uevent(&class_dev->kobj, KOBJ_REMOVE);
|
|
kobject_del(&class_dev->kobj);
|
|
|
|
class_device_put(parent_device);
|
|
class_put(parent_class);
|
|
}
|
|
|
|
void class_device_unregister(struct class_device *class_dev)
|
|
{
|
|
pr_debug("CLASS: Unregistering class device. ID = '%s'\n",
|
|
class_dev->class_id);
|
|
class_device_del(class_dev);
|
|
class_device_put(class_dev);
|
|
}
|
|
|
|
/**
|
|
* class_device_destroy - removes a class device that was created with class_device_create()
|
|
* @cls: the pointer to the struct class that this device was registered * with.
|
|
* @devt: the dev_t of the device that was previously registered.
|
|
*
|
|
* This call unregisters and cleans up a class device that was created with a
|
|
* call to class_device_create()
|
|
*/
|
|
void class_device_destroy(struct class *cls, dev_t devt)
|
|
{
|
|
struct class_device *class_dev = NULL;
|
|
struct class_device *class_dev_tmp;
|
|
|
|
down(&cls->sem);
|
|
list_for_each_entry(class_dev_tmp, &cls->children, node) {
|
|
if (class_dev_tmp->devt == devt) {
|
|
class_dev = class_dev_tmp;
|
|
break;
|
|
}
|
|
}
|
|
up(&cls->sem);
|
|
|
|
if (class_dev)
|
|
class_device_unregister(class_dev);
|
|
}
|
|
|
|
int class_device_rename(struct class_device *class_dev, char *new_name)
|
|
{
|
|
int error = 0;
|
|
char *old_class_name = NULL, *new_class_name = NULL;
|
|
|
|
class_dev = class_device_get(class_dev);
|
|
if (!class_dev)
|
|
return -EINVAL;
|
|
|
|
pr_debug("CLASS: renaming '%s' to '%s'\n", class_dev->class_id,
|
|
new_name);
|
|
|
|
#ifdef CONFIG_SYSFS_DEPRECATED
|
|
if (class_dev->dev)
|
|
old_class_name = make_class_name(class_dev->class->name,
|
|
&class_dev->kobj);
|
|
#endif
|
|
|
|
strlcpy(class_dev->class_id, new_name, KOBJ_NAME_LEN);
|
|
|
|
error = kobject_rename(&class_dev->kobj, new_name);
|
|
|
|
#ifdef CONFIG_SYSFS_DEPRECATED
|
|
if (class_dev->dev) {
|
|
new_class_name = make_class_name(class_dev->class->name,
|
|
&class_dev->kobj);
|
|
sysfs_create_link(&class_dev->dev->kobj, &class_dev->kobj,
|
|
new_class_name);
|
|
sysfs_remove_link(&class_dev->dev->kobj, old_class_name);
|
|
}
|
|
#endif
|
|
class_device_put(class_dev);
|
|
|
|
kfree(old_class_name);
|
|
kfree(new_class_name);
|
|
|
|
return error;
|
|
}
|
|
|
|
struct class_device * class_device_get(struct class_device *class_dev)
|
|
{
|
|
if (class_dev)
|
|
return to_class_dev(kobject_get(&class_dev->kobj));
|
|
return NULL;
|
|
}
|
|
|
|
void class_device_put(struct class_device *class_dev)
|
|
{
|
|
if (class_dev)
|
|
kobject_put(&class_dev->kobj);
|
|
}
|
|
|
|
|
|
int class_interface_register(struct class_interface *class_intf)
|
|
{
|
|
struct class *parent;
|
|
struct class_device *class_dev;
|
|
struct device *dev;
|
|
|
|
if (!class_intf || !class_intf->class)
|
|
return -ENODEV;
|
|
|
|
parent = class_get(class_intf->class);
|
|
if (!parent)
|
|
return -EINVAL;
|
|
|
|
down(&parent->sem);
|
|
list_add_tail(&class_intf->node, &parent->interfaces);
|
|
if (class_intf->add) {
|
|
list_for_each_entry(class_dev, &parent->children, node)
|
|
class_intf->add(class_dev, class_intf);
|
|
}
|
|
if (class_intf->add_dev) {
|
|
list_for_each_entry(dev, &parent->devices, node)
|
|
class_intf->add_dev(dev, class_intf);
|
|
}
|
|
up(&parent->sem);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void class_interface_unregister(struct class_interface *class_intf)
|
|
{
|
|
struct class * parent = class_intf->class;
|
|
struct class_device *class_dev;
|
|
struct device *dev;
|
|
|
|
if (!parent)
|
|
return;
|
|
|
|
down(&parent->sem);
|
|
list_del_init(&class_intf->node);
|
|
if (class_intf->remove) {
|
|
list_for_each_entry(class_dev, &parent->children, node)
|
|
class_intf->remove(class_dev, class_intf);
|
|
}
|
|
if (class_intf->remove_dev) {
|
|
list_for_each_entry(dev, &parent->devices, node)
|
|
class_intf->remove_dev(dev, class_intf);
|
|
}
|
|
up(&parent->sem);
|
|
|
|
class_put(parent);
|
|
}
|
|
|
|
int __init classes_init(void)
|
|
{
|
|
int retval;
|
|
|
|
retval = subsystem_register(&class_subsys);
|
|
if (retval)
|
|
return retval;
|
|
|
|
/* ick, this is ugly, the things we go through to keep from showing up
|
|
* in sysfs... */
|
|
subsystem_init(&class_obj_subsys);
|
|
if (!class_obj_subsys.kset.subsys)
|
|
class_obj_subsys.kset.subsys = &class_obj_subsys;
|
|
return 0;
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(class_create_file);
|
|
EXPORT_SYMBOL_GPL(class_remove_file);
|
|
EXPORT_SYMBOL_GPL(class_register);
|
|
EXPORT_SYMBOL_GPL(class_unregister);
|
|
EXPORT_SYMBOL_GPL(class_create);
|
|
EXPORT_SYMBOL_GPL(class_destroy);
|
|
|
|
EXPORT_SYMBOL_GPL(class_device_register);
|
|
EXPORT_SYMBOL_GPL(class_device_unregister);
|
|
EXPORT_SYMBOL_GPL(class_device_initialize);
|
|
EXPORT_SYMBOL_GPL(class_device_add);
|
|
EXPORT_SYMBOL_GPL(class_device_del);
|
|
EXPORT_SYMBOL_GPL(class_device_get);
|
|
EXPORT_SYMBOL_GPL(class_device_put);
|
|
EXPORT_SYMBOL_GPL(class_device_create);
|
|
EXPORT_SYMBOL_GPL(class_device_destroy);
|
|
EXPORT_SYMBOL_GPL(class_device_create_file);
|
|
EXPORT_SYMBOL_GPL(class_device_remove_file);
|
|
EXPORT_SYMBOL_GPL(class_device_create_bin_file);
|
|
EXPORT_SYMBOL_GPL(class_device_remove_bin_file);
|
|
|
|
EXPORT_SYMBOL_GPL(class_interface_register);
|
|
EXPORT_SYMBOL_GPL(class_interface_unregister);
|