1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (C) 2011 Instituto Nokia de Tecnologia
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Authors:
6*4882a593Smuzhiyun * Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
7*4882a593Smuzhiyun * Lauro Ramos Venancio <lauro.venancio@openbossa.org>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/nfc.h>
11*4882a593Smuzhiyun #include <linux/module.h>
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #include "nfc.h"
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun static DEFINE_RWLOCK(proto_tab_lock);
16*4882a593Smuzhiyun static const struct nfc_protocol *proto_tab[NFC_SOCKPROTO_MAX];
17*4882a593Smuzhiyun
nfc_sock_create(struct net * net,struct socket * sock,int proto,int kern)18*4882a593Smuzhiyun static int nfc_sock_create(struct net *net, struct socket *sock, int proto,
19*4882a593Smuzhiyun int kern)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun int rc = -EPROTONOSUPPORT;
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun if (net != &init_net)
24*4882a593Smuzhiyun return -EAFNOSUPPORT;
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun if (proto < 0 || proto >= NFC_SOCKPROTO_MAX)
27*4882a593Smuzhiyun return -EINVAL;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun read_lock(&proto_tab_lock);
30*4882a593Smuzhiyun if (proto_tab[proto] && try_module_get(proto_tab[proto]->owner)) {
31*4882a593Smuzhiyun rc = proto_tab[proto]->create(net, sock, proto_tab[proto], kern);
32*4882a593Smuzhiyun module_put(proto_tab[proto]->owner);
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun read_unlock(&proto_tab_lock);
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun return rc;
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun static const struct net_proto_family nfc_sock_family_ops = {
40*4882a593Smuzhiyun .owner = THIS_MODULE,
41*4882a593Smuzhiyun .family = PF_NFC,
42*4882a593Smuzhiyun .create = nfc_sock_create,
43*4882a593Smuzhiyun };
44*4882a593Smuzhiyun
nfc_proto_register(const struct nfc_protocol * nfc_proto)45*4882a593Smuzhiyun int nfc_proto_register(const struct nfc_protocol *nfc_proto)
46*4882a593Smuzhiyun {
47*4882a593Smuzhiyun int rc;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun if (nfc_proto->id < 0 || nfc_proto->id >= NFC_SOCKPROTO_MAX)
50*4882a593Smuzhiyun return -EINVAL;
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun rc = proto_register(nfc_proto->proto, 0);
53*4882a593Smuzhiyun if (rc)
54*4882a593Smuzhiyun return rc;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun write_lock(&proto_tab_lock);
57*4882a593Smuzhiyun if (proto_tab[nfc_proto->id])
58*4882a593Smuzhiyun rc = -EBUSY;
59*4882a593Smuzhiyun else
60*4882a593Smuzhiyun proto_tab[nfc_proto->id] = nfc_proto;
61*4882a593Smuzhiyun write_unlock(&proto_tab_lock);
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun if (rc)
64*4882a593Smuzhiyun proto_unregister(nfc_proto->proto);
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun return rc;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun EXPORT_SYMBOL(nfc_proto_register);
69*4882a593Smuzhiyun
nfc_proto_unregister(const struct nfc_protocol * nfc_proto)70*4882a593Smuzhiyun void nfc_proto_unregister(const struct nfc_protocol *nfc_proto)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun write_lock(&proto_tab_lock);
73*4882a593Smuzhiyun proto_tab[nfc_proto->id] = NULL;
74*4882a593Smuzhiyun write_unlock(&proto_tab_lock);
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun proto_unregister(nfc_proto->proto);
77*4882a593Smuzhiyun }
78*4882a593Smuzhiyun EXPORT_SYMBOL(nfc_proto_unregister);
79*4882a593Smuzhiyun
af_nfc_init(void)80*4882a593Smuzhiyun int __init af_nfc_init(void)
81*4882a593Smuzhiyun {
82*4882a593Smuzhiyun return sock_register(&nfc_sock_family_ops);
83*4882a593Smuzhiyun }
84*4882a593Smuzhiyun
af_nfc_exit(void)85*4882a593Smuzhiyun void af_nfc_exit(void)
86*4882a593Smuzhiyun {
87*4882a593Smuzhiyun sock_unregister(PF_NFC);
88*4882a593Smuzhiyun }
89