projects/linux·blob master · refs

68 lines · 1.7 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * All the USB notify logic
4 *
5 * (C) Copyright 2005 Greg Kroah-Hartman <[email protected]>
6 *
7 * notifier functions originally based on those in kernel/sys.c
8 * but fixed up to not be so broken.
9 *
10 * Released under the GPLv2 only.
11 */
12
13
14#include <linux/kernel.h>
15#include <linux/export.h>
16#include <linux/notifier.h>
17#include <linux/usb.h>
18#include <linux/mutex.h>
19#include "usb.h"
20
21static BLOCKING_NOTIFIER_HEAD(usb_notifier_list);
22
23/**
24 * usb_register_notify - register a notifier callback whenever a usb change happens
25 * @nb: pointer to the notifier block for the callback events.
26 *
27 * These changes are either USB devices or busses being added or removed.
28 */
29void usb_register_notify(struct notifier_block *nb)
30{
31 blocking_notifier_chain_register(&usb_notifier_list, nb);
32}
33EXPORT_SYMBOL_GPL(usb_register_notify);
34
35/**
36 * usb_unregister_notify - unregister a notifier callback
37 * @nb: pointer to the notifier block for the callback events.
38 *
39 * usb_register_notify() must have been previously called for this function
40 * to work properly.
41 */
42void usb_unregister_notify(struct notifier_block *nb)
43{
44 blocking_notifier_chain_unregister(&usb_notifier_list, nb);
45}
46EXPORT_SYMBOL_GPL(usb_unregister_notify);
47
48
49void usb_notify_add_device(struct usb_device *udev)
50{
51 blocking_notifier_call_chain(&usb_notifier_list, USB_DEVICE_ADD, udev);
52}
53
54void usb_notify_remove_device(struct usb_device *udev)
55{
56 blocking_notifier_call_chain(&usb_notifier_list,
57 USB_DEVICE_REMOVE, udev);
58}
59
60void usb_notify_add_bus(struct usb_bus *ubus)
61{
62 blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_ADD, ubus);
63}
64
65void usb_notify_remove_bus(struct usb_bus *ubus)
66{
67 blocking_notifier_call_chain(&usb_notifier_list, USB_BUS_REMOVE, ubus);
68}