[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/net/nfc/netlink.c b/ap/os/linux/linux-3.4.x/net/nfc/netlink.c
new file mode 100644
index 0000000..6404052
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/nfc/netlink.c
@@ -0,0 +1,713 @@
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ *    Aloisio Almeida Jr <aloisio.almeida@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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
+
+#include <net/genetlink.h>
+#include <linux/nfc.h>
+#include <linux/slab.h>
+
+#include "nfc.h"
+
+static struct genl_multicast_group nfc_genl_event_mcgrp = {
+	.name = NFC_GENL_MCAST_EVENT_NAME,
+};
+
+struct genl_family nfc_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = 0,
+	.name = NFC_GENL_NAME,
+	.version = NFC_GENL_VERSION,
+	.maxattr = NFC_ATTR_MAX,
+};
+
+static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
+	[NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
+	[NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
+				.len = NFC_DEVICE_NAME_MAXSIZE },
+	[NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
+	[NFC_ATTR_COMM_MODE] = { .type = NLA_U8 },
+	[NFC_ATTR_RF_MODE] = { .type = NLA_U8 },
+	[NFC_ATTR_DEVICE_POWERED] = { .type = NLA_U8 },
+};
+
+static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
+				struct netlink_callback *cb, int flags)
+{
+	void *hdr;
+
+	hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
+			  &nfc_genl_family, flags, NFC_CMD_GET_TARGET);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
+
+	NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target->idx);
+	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, target->supported_protocols);
+	NLA_PUT_U16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res);
+	NLA_PUT_U8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res);
+	if (target->nfcid1_len > 0)
+		NLA_PUT(msg, NFC_ATTR_TARGET_NFCID1, target->nfcid1_len,
+			target->nfcid1);
+	if (target->sensb_res_len > 0)
+		NLA_PUT(msg, NFC_ATTR_TARGET_SENSB_RES, target->sensb_res_len,
+			target->sensb_res);
+	if (target->sensf_res_len > 0)
+		NLA_PUT(msg, NFC_ATTR_TARGET_SENSF_RES, target->sensf_res_len,
+			target->sensf_res);
+
+	return genlmsg_end(msg, hdr);
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+	return -EMSGSIZE;
+}
+
+static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+
+	rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
+			 nfc_genl_family.attrbuf,
+			 nfc_genl_family.maxattr,
+			 nfc_genl_policy);
+	if (rc < 0)
+		return ERR_PTR(rc);
+
+	if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
+		return ERR_PTR(-EINVAL);
+
+	idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return ERR_PTR(-ENODEV);
+
+	return dev;
+}
+
+static int nfc_genl_dump_targets(struct sk_buff *skb,
+				 struct netlink_callback *cb)
+{
+	int i = cb->args[0];
+	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
+	int rc;
+
+	if (!dev) {
+		dev = __get_device_from_cb(cb);
+		if (IS_ERR(dev))
+			return PTR_ERR(dev);
+
+		cb->args[1] = (long) dev;
+	}
+
+	spin_lock_bh(&dev->targets_lock);
+
+	cb->seq = dev->targets_generation;
+
+	while (i < dev->n_targets) {
+		rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
+					  NLM_F_MULTI);
+		if (rc < 0)
+			break;
+
+		i++;
+	}
+
+	spin_unlock_bh(&dev->targets_lock);
+
+	cb->args[0] = i;
+
+	return skb->len;
+}
+
+static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
+{
+	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
+
+	if (dev)
+		nfc_put_device(dev);
+
+	return 0;
+}
+
+int nfc_genl_targets_found(struct nfc_dev *dev)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	dev->genl_data.poll_req_pid = 0;
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+	if (!msg)
+		return -ENOMEM;
+
+	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+			  NFC_EVENT_TARGETS_FOUND);
+	if (!hdr)
+		goto free_msg;
+
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+
+	genlmsg_end(msg, hdr);
+
+	return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+free_msg:
+	nlmsg_free(msg);
+	return -EMSGSIZE;
+}
+
+int nfc_genl_device_added(struct nfc_dev *dev)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+			  NFC_EVENT_DEVICE_ADDED);
+	if (!hdr)
+		goto free_msg;
+
+	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
+	NLA_PUT_U8(msg, NFC_ATTR_DEVICE_POWERED, dev->dev_up);
+
+	genlmsg_end(msg, hdr);
+
+	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
+
+	return 0;
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+free_msg:
+	nlmsg_free(msg);
+	return -EMSGSIZE;
+}
+
+int nfc_genl_device_removed(struct nfc_dev *dev)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!msg)
+		return -ENOMEM;
+
+	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+			  NFC_EVENT_DEVICE_REMOVED);
+	if (!hdr)
+		goto free_msg;
+
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+
+	genlmsg_end(msg, hdr);
+
+	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
+
+	return 0;
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+free_msg:
+	nlmsg_free(msg);
+	return -EMSGSIZE;
+}
+
+static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev,
+				u32 pid, u32 seq,
+				struct netlink_callback *cb,
+				int flags)
+{
+	void *hdr;
+
+	hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags,
+			  NFC_CMD_GET_DEVICE);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	if (cb)
+		genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
+
+	NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+	NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
+	NLA_PUT_U8(msg, NFC_ATTR_DEVICE_POWERED, dev->dev_up);
+
+	return genlmsg_end(msg, hdr);
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+	return -EMSGSIZE;
+}
+
+static int nfc_genl_dump_devices(struct sk_buff *skb,
+				 struct netlink_callback *cb)
+{
+	struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
+	struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
+	bool first_call = false;
+
+	if (!iter) {
+		first_call = true;
+		iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL);
+		if (!iter)
+			return -ENOMEM;
+		cb->args[0] = (long) iter;
+	}
+
+	mutex_lock(&nfc_devlist_mutex);
+
+	cb->seq = nfc_devlist_generation;
+
+	if (first_call) {
+		nfc_device_iter_init(iter);
+		dev = nfc_device_iter_next(iter);
+	}
+
+	while (dev) {
+		int rc;
+
+		rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid,
+					  cb->nlh->nlmsg_seq, cb, NLM_F_MULTI);
+		if (rc < 0)
+			break;
+
+		dev = nfc_device_iter_next(iter);
+	}
+
+	mutex_unlock(&nfc_devlist_mutex);
+
+	cb->args[1] = (long) dev;
+
+	return skb->len;
+}
+
+static int nfc_genl_dump_devices_done(struct netlink_callback *cb)
+{
+	struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
+
+	nfc_device_iter_exit(iter);
+	kfree(iter);
+
+	return 0;
+}
+
+int nfc_genl_dep_link_up_event(struct nfc_dev *dev, u32 target_idx,
+			       u8 comm_mode, u8 rf_mode)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	pr_debug("DEP link is up\n");
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+	if (!msg)
+		return -ENOMEM;
+
+	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0, NFC_CMD_DEP_LINK_UP);
+	if (!hdr)
+		goto free_msg;
+
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+	if (rf_mode == NFC_RF_INITIATOR)
+		NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target_idx);
+	NLA_PUT_U8(msg, NFC_ATTR_COMM_MODE, comm_mode);
+	NLA_PUT_U8(msg, NFC_ATTR_RF_MODE, rf_mode);
+
+	genlmsg_end(msg, hdr);
+
+	dev->dep_link_up = true;
+
+	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
+
+	return 0;
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+free_msg:
+	nlmsg_free(msg);
+	return -EMSGSIZE;
+}
+
+int nfc_genl_dep_link_down_event(struct nfc_dev *dev)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	pr_debug("DEP link is down\n");
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+	if (!msg)
+		return -ENOMEM;
+
+	hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+			  NFC_CMD_DEP_LINK_DOWN);
+	if (!hdr)
+		goto free_msg;
+
+	NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
+
+	genlmsg_end(msg, hdr);
+
+	genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
+
+	return 0;
+
+nla_put_failure:
+	genlmsg_cancel(msg, hdr);
+free_msg:
+	nlmsg_free(msg);
+	return -EMSGSIZE;
+}
+
+static int nfc_genl_get_device(struct sk_buff *skb, struct genl_info *info)
+{
+	struct sk_buff *msg;
+	struct nfc_dev *dev;
+	u32 idx;
+	int rc = -ENOBUFS;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!msg) {
+		rc = -ENOMEM;
+		goto out_putdev;
+	}
+
+	rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq,
+				  NULL, 0);
+	if (rc < 0)
+		goto out_free;
+
+	nfc_put_device(dev);
+
+	return genlmsg_reply(msg, info);
+
+out_free:
+	nlmsg_free(msg);
+out_putdev:
+	nfc_put_device(dev);
+	return rc;
+}
+
+static int nfc_genl_dev_up(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	rc = nfc_dev_up(dev);
+
+	nfc_put_device(dev);
+	return rc;
+}
+
+static int nfc_genl_dev_down(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	rc = nfc_dev_down(dev);
+
+	nfc_put_device(dev);
+	return rc;
+}
+
+static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+	u32 protocols;
+
+	pr_debug("Poll start\n");
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+	    !info->attrs[NFC_ATTR_PROTOCOLS])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+	protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->genl_data.genl_data_mutex);
+
+	rc = nfc_start_poll(dev, protocols);
+	if (!rc)
+		dev->genl_data.poll_req_pid = info->snd_pid;
+
+	mutex_unlock(&dev->genl_data.genl_data_mutex);
+
+	nfc_put_device(dev);
+	return rc;
+}
+
+static int nfc_genl_stop_poll(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->genl_data.genl_data_mutex);
+
+	if (dev->genl_data.poll_req_pid != info->snd_pid) {
+		rc = -EBUSY;
+		goto out;
+	}
+
+	rc = nfc_stop_poll(dev);
+	dev->genl_data.poll_req_pid = 0;
+
+out:
+	mutex_unlock(&dev->genl_data.genl_data_mutex);
+	nfc_put_device(dev);
+	return rc;
+}
+
+static int nfc_genl_dep_link_up(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc, tgt_idx;
+	u32 idx;
+	u8 comm;
+
+	pr_debug("DEP link up\n");
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+	    !info->attrs[NFC_ATTR_COMM_MODE])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+	if (!info->attrs[NFC_ATTR_TARGET_INDEX])
+		tgt_idx = NFC_TARGET_IDX_ANY;
+	else
+		tgt_idx = nla_get_u32(info->attrs[NFC_ATTR_TARGET_INDEX]);
+
+	comm = nla_get_u8(info->attrs[NFC_ATTR_COMM_MODE]);
+
+	if (comm != NFC_COMM_ACTIVE && comm != NFC_COMM_PASSIVE)
+		return -EINVAL;
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	rc = nfc_dep_link_up(dev, tgt_idx, comm);
+
+	nfc_put_device(dev);
+
+	return rc;
+}
+
+static int nfc_genl_dep_link_down(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nfc_dev *dev;
+	int rc;
+	u32 idx;
+
+	if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+		return -EINVAL;
+
+	idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+	dev = nfc_get_device(idx);
+	if (!dev)
+		return -ENODEV;
+
+	rc = nfc_dep_link_down(dev);
+
+	nfc_put_device(dev);
+	return rc;
+}
+
+static struct genl_ops nfc_genl_ops[] = {
+	{
+		.cmd = NFC_CMD_GET_DEVICE,
+		.doit = nfc_genl_get_device,
+		.dumpit = nfc_genl_dump_devices,
+		.done = nfc_genl_dump_devices_done,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_DEV_UP,
+		.doit = nfc_genl_dev_up,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_DEV_DOWN,
+		.doit = nfc_genl_dev_down,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_START_POLL,
+		.doit = nfc_genl_start_poll,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_STOP_POLL,
+		.doit = nfc_genl_stop_poll,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_DEP_LINK_UP,
+		.doit = nfc_genl_dep_link_up,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_DEP_LINK_DOWN,
+		.doit = nfc_genl_dep_link_down,
+		.policy = nfc_genl_policy,
+	},
+	{
+		.cmd = NFC_CMD_GET_TARGET,
+		.dumpit = nfc_genl_dump_targets,
+		.done = nfc_genl_dump_targets_done,
+		.policy = nfc_genl_policy,
+	},
+};
+
+static int nfc_genl_rcv_nl_event(struct notifier_block *this,
+				 unsigned long event, void *ptr)
+{
+	struct netlink_notify *n = ptr;
+	struct class_dev_iter iter;
+	struct nfc_dev *dev;
+
+	if (event != NETLINK_URELEASE || n->protocol != NETLINK_GENERIC)
+		goto out;
+
+	pr_debug("NETLINK_URELEASE event from id %d\n", n->pid);
+
+	nfc_device_iter_init(&iter);
+	dev = nfc_device_iter_next(&iter);
+
+	while (dev) {
+		if (dev->genl_data.poll_req_pid == n->pid) {
+			nfc_stop_poll(dev);
+			dev->genl_data.poll_req_pid = 0;
+		}
+		dev = nfc_device_iter_next(&iter);
+	}
+
+	nfc_device_iter_exit(&iter);
+
+out:
+	return NOTIFY_DONE;
+}
+
+void nfc_genl_data_init(struct nfc_genl_data *genl_data)
+{
+	genl_data->poll_req_pid = 0;
+	mutex_init(&genl_data->genl_data_mutex);
+}
+
+void nfc_genl_data_exit(struct nfc_genl_data *genl_data)
+{
+	mutex_destroy(&genl_data->genl_data_mutex);
+}
+
+static struct notifier_block nl_notifier = {
+	.notifier_call  = nfc_genl_rcv_nl_event,
+};
+
+/**
+ * nfc_genl_init() - Initialize netlink interface
+ *
+ * This initialization function registers the nfc netlink family.
+ */
+int __init nfc_genl_init(void)
+{
+	int rc;
+
+	rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops,
+					   ARRAY_SIZE(nfc_genl_ops));
+	if (rc)
+		return rc;
+
+	rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp);
+
+	netlink_register_notifier(&nl_notifier);
+
+	return rc;
+}
+
+/**
+ * nfc_genl_exit() - Deinitialize netlink interface
+ *
+ * This exit function unregisters the nfc netlink family.
+ */
+void nfc_genl_exit(void)
+{
+	netlink_unregister_notifier(&nl_notifier);
+	genl_unregister_family(&nfc_genl_family);
+}