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/*
* All the USB notify logic
*
* (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
*
* notifier functions originally based on those in kernel/sys.c
* but fixed up to not be so broken.
*
* Released under the GPLv2 only.
* SPDX-License-Identifier: GPL-2.0
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/notifier.h>
#include <linux/usb.h>
#include <linux/mutex.h>
#include "usb.h"
static BLOCKING_NOTIFIER_HEAD(usb_notifier_list);
/**
* usb_register_notify - register a notifier callback whenever a usb change happens
* @nb: pointer to the notifier block for the callback events.
*
* These changes are either USB devices or busses being added or removed.
*/
void usb_register_notify(struct notifier_block *nb)
{
blocking_notifier_chain_register(&usb_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(usb_register_notify);
/**
* usb_unregister_notify - unregister a notifier callback
* @nb: pointer to the notifier block for the callback events.
*
* usb_register_notify() must have been previously called for this function
* to work properly.
*/
void usb_unregister_notify(struct notifier_block *nb)
{
blocking_notifier_chain_unregister(&usb_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(usb_unregister_notify);
void usb_notify_add_device(struct usb_device *udev)
{
blocking_notifier_call_chain(&usb_notifier_list, USB_DEVICE_ADD, udev);
}
void usb_notify_remove_device(struct usb_device *udev)
{
/* Protect against simultaneous usbfs open */
mutex_lock(&usbfs_mutex);
blocking_notifier_call_chain(&usb_notifier_list,
USB_DEVICE_REMOVE, udev);
mutex_unlock(&usbfs_mutex);
}
void usb_notify_add_bus(struct usb_bus *ubus)
{
blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_ADD, ubus);
}
void usb_notify_remove_bus(struct usb_bus *ubus)
{
blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_REMOVE, ubus);
}