NFC: add NFC socket family

[pandora-kernel.git] / net / nfc / af_nfc.c

diff --git a/net/nfc/af_nfc.c b/net/nfc/af_nfc.c
new file mode 100644 (file)
index 0000000..e982cef
--- /dev/null
+++ b/net/nfc/af_nfc.c
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the
+ * Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/nfc.h>
+
+#include "nfc.h"
+
+static DEFINE_RWLOCK(proto_tab_lock);
+static const struct nfc_protocol *proto_tab[NFC_SOCKPROTO_MAX];
+
+static int nfc_sock_create(struct net *net, struct socket *sock, int proto,
+                                                               int kern)
+{
+       int rc = -EPROTONOSUPPORT;
+
+       if (net != &init_net)
+               return -EAFNOSUPPORT;
+
+       if (proto < 0 || proto >= NFC_SOCKPROTO_MAX)
+               return -EINVAL;
+
+       read_lock(&proto_tab_lock);
+       if (proto_tab[proto] && try_module_get(proto_tab[proto]->owner)) {
+               rc = proto_tab[proto]->create(net, sock, proto_tab[proto]);
+               module_put(proto_tab[proto]->owner);
+       }
+       read_unlock(&proto_tab_lock);
+
+       return rc;
+}
+
+static struct net_proto_family nfc_sock_family_ops = {
+       .owner  = THIS_MODULE,
+       .family = PF_NFC,
+       .create = nfc_sock_create,
+};
+
+int nfc_proto_register(const struct nfc_protocol *nfc_proto)
+{
+       int rc;
+
+       if (nfc_proto->id < 0 || nfc_proto->id >= NFC_SOCKPROTO_MAX)
+               return -EINVAL;
+
+       rc = proto_register(nfc_proto->proto, 0);
+       if (rc)
+               return rc;
+
+       write_lock(&proto_tab_lock);
+       if (proto_tab[nfc_proto->id])
+               rc = -EBUSY;
+       else
+               proto_tab[nfc_proto->id] = nfc_proto;
+       write_unlock(&proto_tab_lock);
+
+       return rc;
+}
+EXPORT_SYMBOL(nfc_proto_register);
+
+void nfc_proto_unregister(const struct nfc_protocol *nfc_proto)
+{
+       write_lock(&proto_tab_lock);
+       proto_tab[nfc_proto->id] = NULL;
+       write_unlock(&proto_tab_lock);
+
+       proto_unregister(nfc_proto->proto);
+}
+EXPORT_SYMBOL(nfc_proto_unregister);
+
+int __init af_nfc_init(void)
+{
+       return sock_register(&nfc_sock_family_ops);
+}
+
+void af_nfc_exit(void)
+{
+       sock_unregister(PF_NFC);
+}