/* * 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. * */ #include <linux/kernel.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); }