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, write to the 20 * Free Software Foundation, Inc., 21 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 22 */ 23 24 #include <linux/nfc.h> 25 26 #include "nfc.h" 27 28 static DEFINE_RWLOCK(proto_tab_lock); 29 static const struct nfc_protocol *proto_tab[NFC_SOCKPROTO_MAX]; 30 31 static int nfc_sock_create(struct net *net, struct socket *sock, int proto, 32 int kern) 33 { 34 int rc = -EPROTONOSUPPORT; 35 36 if (net != &init_net) 37 return -EAFNOSUPPORT; 38 39 if (proto < 0 || proto >= NFC_SOCKPROTO_MAX) 40 return -EINVAL; 41 42 read_lock(&proto_tab_lock); 43 if (proto_tab[proto] && try_module_get(proto_tab[proto]->owner)) { 44 rc = proto_tab[proto]->create(net, sock, proto_tab[proto]); 45 module_put(proto_tab[proto]->owner); 46 } 47 read_unlock(&proto_tab_lock); 48 49 return rc; 50 } 51 52 static struct net_proto_family nfc_sock_family_ops = { 53 .owner = THIS_MODULE, 54 .family = PF_NFC, 55 .create = nfc_sock_create, 56 }; 57 58 int nfc_proto_register(const struct nfc_protocol *nfc_proto) 59 { 60 int rc; 61 62 if (nfc_proto->id < 0 || nfc_proto->id >= NFC_SOCKPROTO_MAX) 63 return -EINVAL; 64 65 rc = proto_register(nfc_proto->proto, 0); 66 if (rc) 67 return rc; 68 69 write_lock(&proto_tab_lock); 70 if (proto_tab[nfc_proto->id]) 71 rc = -EBUSY; 72 else 73 proto_tab[nfc_proto->id] = nfc_proto; 74 write_unlock(&proto_tab_lock); 75 76 return rc; 77 } 78 EXPORT_SYMBOL(nfc_proto_register); 79 80 void nfc_proto_unregister(const struct nfc_protocol *nfc_proto) 81 { 82 write_lock(&proto_tab_lock); 83 proto_tab[nfc_proto->id] = NULL; 84 write_unlock(&proto_tab_lock); 85 86 proto_unregister(nfc_proto->proto); 87 } 88 EXPORT_SYMBOL(nfc_proto_unregister); 89 90 int __init af_nfc_init(void) 91 { 92 return sock_register(&nfc_sock_family_ops); 93 } 94 95 void af_nfc_exit(void) 96 { 97 sock_unregister(PF_NFC); 98 } 99