fb_notify.c

 1/*
 2 *  linux/drivers/video/fb_notify.c
 3 *
 4 *  Copyright (C) 2006 Antonino Daplas <adaplas@pol.net>
 5 *
 6 *	2001 - Documented with DocBook
 7 *	- Brad Douglas <brad@neruo.com>
 8 *
 9 * This file is subject to the terms and conditions of the GNU General Public
10 * License.  See the file COPYING in the main directory of this archive
11 * for more details.
12 */
13#include <linux/fb.h>
14#include <linux/notifier.h>
15#include <linux/export.h>
16
17static BLOCKING_NOTIFIER_HEAD(fb_notifier_list);
18
19/**
20 *	fb_register_client - register a client notifier
21 *	@nb: notifier block to callback on events
22 *
23 *	Return: 0 on success, negative error code on failure.
24 */
25int fb_register_client(struct notifier_block *nb)
26{
27	return blocking_notifier_chain_register(&fb_notifier_list, nb);
28}
29EXPORT_SYMBOL(fb_register_client);
30
31/**
32 *	fb_unregister_client - unregister a client notifier
33 *	@nb: notifier block to callback on events
34 *
35 *	Return: 0 on success, negative error code on failure.
36 */
37int fb_unregister_client(struct notifier_block *nb)
38{
39	return blocking_notifier_chain_unregister(&fb_notifier_list, nb);
40}
41EXPORT_SYMBOL(fb_unregister_client);
42
43/**
44 * fb_notifier_call_chain - notify clients of fb_events
45 * @val: value passed to callback
46 * @v: pointer passed to callback
47 *
48 * Return: The return value of the last notifier function
49 */
50int fb_notifier_call_chain(unsigned long val, void *v)
51{
52	return blocking_notifier_call_chain(&fb_notifier_list, val, v);
53}
54EXPORT_SYMBOL_GPL(fb_notifier_call_chain);