1/*
2 * Copyright (C) 2011 Instituto Nokia de Tecnologia
3 *
4 * Authors:
5 *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
6 *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22#include <linux/nfc.h>
23#include <linux/module.h>
24
25#include "nfc.h"
26
27static DEFINE_RWLOCK(proto_tab_lock);
28static const struct nfc_protocol *proto_tab[NFC_SOCKPROTO_MAX];
29
30static int nfc_sock_create(struct net *net, struct socket *sock, int proto,
31			   int kern)
32{
33	int rc = -EPROTONOSUPPORT;
34
35	if (net != &init_net)
36		return -EAFNOSUPPORT;
37
38	if (proto < 0 || proto >= NFC_SOCKPROTO_MAX)
39		return -EINVAL;
40
41	read_lock(&proto_tab_lock);
42	if (proto_tab[proto] &&	try_module_get(proto_tab[proto]->owner)) {
43		rc = proto_tab[proto]->create(net, sock, proto_tab[proto]);
44		module_put(proto_tab[proto]->owner);
45	}
46	read_unlock(&proto_tab_lock);
47
48	return rc;
49}
50
51static struct net_proto_family nfc_sock_family_ops = {
52	.owner  = THIS_MODULE,
53	.family = PF_NFC,
54	.create = nfc_sock_create,
55};
56
57int nfc_proto_register(const struct nfc_protocol *nfc_proto)
58{
59	int rc;
60
61	if (nfc_proto->id < 0 || nfc_proto->id >= NFC_SOCKPROTO_MAX)
62		return -EINVAL;
63
64	rc = proto_register(nfc_proto->proto, 0);
65	if (rc)
66		return rc;
67
68	write_lock(&proto_tab_lock);
69	if (proto_tab[nfc_proto->id])
70		rc = -EBUSY;
71	else
72		proto_tab[nfc_proto->id] = nfc_proto;
73	write_unlock(&proto_tab_lock);
74
75	return rc;
76}
77EXPORT_SYMBOL(nfc_proto_register);
78
79void nfc_proto_unregister(const struct nfc_protocol *nfc_proto)
80{
81	write_lock(&proto_tab_lock);
82	proto_tab[nfc_proto->id] = NULL;
83	write_unlock(&proto_tab_lock);
84
85	proto_unregister(nfc_proto->proto);
86}
87EXPORT_SYMBOL(nfc_proto_unregister);
88
89int __init af_nfc_init(void)
90{
91	return sock_register(&nfc_sock_family_ops);
92}
93
94void af_nfc_exit(void)
95{
96	sock_unregister(PF_NFC);
97}
98