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 #include <linux/module.h> 26 27 #include "nfc.h" 28 29 static DEFINE_RWLOCK(proto_tab_lock); 30 static const struct nfc_protocol *proto_tab[NFC_SOCKPROTO_MAX]; 31 32 static int nfc_sock_create(struct net *net, struct socket *sock, int proto, 33 int kern) 34 { 35 int rc = -EPROTONOSUPPORT; 36 37 if (net != &init_net) 38 return -EAFNOSUPPORT; 39 40 if (proto < 0 || proto >= NFC_SOCKPROTO_MAX) 41 return -EINVAL; 42 43 read_lock(&proto_tab_lock); 44 if (proto_tab[proto] && try_module_get(proto_tab[proto]->owner)) { 45 rc = proto_tab[proto]->create(net, sock, proto_tab[proto]); 46 module_put(proto_tab[proto]->owner); 47 } 48 read_unlock(&proto_tab_lock); 49 50 return rc; 51 } 52 53 static struct net_proto_family nfc_sock_family_ops = { 54 .owner = THIS_MODULE, 55 .family = PF_NFC, 56 .create = nfc_sock_create, 57 }; 58 59 int nfc_proto_register(const struct nfc_protocol *nfc_proto) 60 { 61 int rc; 62 63 if (nfc_proto->id < 0 || nfc_proto->id >= NFC_SOCKPROTO_MAX) 64 return -EINVAL; 65 66 rc = proto_register(nfc_proto->proto, 0); 67 if (rc) 68 return rc; 69 70 write_lock(&proto_tab_lock); 71 if (proto_tab[nfc_proto->id]) 72 rc = -EBUSY; 73 else 74 proto_tab[nfc_proto->id] = nfc_proto; 75 write_unlock(&proto_tab_lock); 76 77 return rc; 78 } 79 EXPORT_SYMBOL(nfc_proto_register); 80 81 void nfc_proto_unregister(const struct nfc_protocol *nfc_proto) 82 { 83 write_lock(&proto_tab_lock); 84 proto_tab[nfc_proto->id] = NULL; 85 write_unlock(&proto_tab_lock); 86 87 proto_unregister(nfc_proto->proto); 88 } 89 EXPORT_SYMBOL(nfc_proto_unregister); 90 91 int __init af_nfc_init(void) 92 { 93 return sock_register(&nfc_sock_family_ops); 94 } 95 96 void af_nfc_exit(void) 97 { 98 sock_unregister(PF_NFC); 99 } 100