/*
 * Copyright 2007, 2008, 2009 Siemens AG
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * 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.
 *
 * Written by:
 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
 * Sergey Lapin <slapin@ossfans.org>
 * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
 */

#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/crc-ccitt.h>
#include <linux/ieee802154.h>

#include <net/mac802154.h>
#include <net/netlink.h>
#include <net/cfg802154.h>
#include <linux/nl802154.h>

#include "ieee802154_i.h"

static netdev_tx_t mac802154_monitor_xmit(struct sk_buff *skb,
					  struct net_device *dev)
{
	struct ieee802154_sub_if_data *sdata;
	u8 chan, page;

	sdata = netdev_priv(dev);

	/* FIXME: locking */
	chan = sdata->hw->phy->current_channel;
	page = sdata->hw->phy->current_page;

	if (chan == MAC802154_CHAN_NONE) /* not initialized */
		return NETDEV_TX_OK;

	if (WARN_ON(page >= WPAN_NUM_PAGES) ||
	    WARN_ON(chan >= WPAN_NUM_CHANNELS))
		return NETDEV_TX_OK;

	skb->skb_iif = dev->ifindex;
	dev->stats.tx_packets++;
	dev->stats.tx_bytes += skb->len;

	return mac802154_tx(sdata->hw, skb, page, chan);
}


void mac802154_monitors_rx(struct ieee802154_local *local, struct sk_buff *skb)
{
	struct sk_buff *skb2;
	struct ieee802154_sub_if_data *sdata;
	u16 crc = crc_ccitt(0, skb->data, skb->len);
	u8 *data;

	rcu_read_lock();
	list_for_each_entry_rcu(sdata, &local->slaves, list) {
		if (sdata->type != IEEE802154_DEV_MONITOR ||
		    !netif_running(sdata->dev))
			continue;

		skb2 = skb_clone(skb, GFP_ATOMIC);
		skb2->dev = sdata->dev;
		skb2->pkt_type = PACKET_HOST;
		data = skb_put(skb2, 2);
		data[0] = crc & 0xff;
		data[1] = crc >> 8;

		netif_rx_ni(skb2);
	}
	rcu_read_unlock();
}

static const struct net_device_ops mac802154_monitor_ops = {
	.ndo_open		= mac802154_slave_open,
	.ndo_stop		= mac802154_slave_close,
	.ndo_start_xmit		= mac802154_monitor_xmit,
};

void mac802154_monitor_setup(struct net_device *dev)
{
	struct ieee802154_sub_if_data *sdata;

	dev->addr_len		= 0;
	dev->hard_header_len	= 0;
	dev->needed_tailroom	= 2; /* room for FCS */
	dev->mtu		= IEEE802154_MTU;
	dev->tx_queue_len	= 10;
	dev->type		= ARPHRD_IEEE802154_MONITOR;
	dev->flags		= IFF_NOARP | IFF_BROADCAST;
	dev->watchdog_timeo	= 0;

	dev->destructor		= free_netdev;
	dev->netdev_ops		= &mac802154_monitor_ops;
	dev->ml_priv		= &mac802154_mlme_reduced;

	sdata = netdev_priv(dev);
	sdata->type = IEEE802154_DEV_MONITOR;

	sdata->chan = MAC802154_CHAN_NONE; /* not initialized */
	sdata->page = 0;
}