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