/*!
 *  @file	wilc_wfi_netdevice.c
 *  @brief	File Operations OS wrapper functionality
 *  @author	mdaftedar
 *  @sa		wilc_wfi_netdevice.h
 *  @date	01 MAR 2012
 *  @version	1.0
 */

#ifdef SIMULATION

#include "wilc_wfi_cfgoperations.h"
#include "host_interface.h"


MODULE_AUTHOR("Mai Daftedar");
MODULE_LICENSE("Dual BSD/GPL");


struct net_device *WILC_WFI_devs[2];

/*
 * Transmitter lockup simulation, normally disabled.
 */
static int lockup;
module_param(lockup, int, 0);

static int timeout = WILC_WFI_TIMEOUT;
module_param(timeout, int, 0);

/*
 * Do we run in NAPI mode?
 */
static int use_napi ;
module_param(use_napi, int, 0);


/*
 * A structure representing an in-flight packet.
 */
struct WILC_WFI_packet {
	struct WILC_WFI_packet *next;
	struct net_device *dev;
	int datalen;
	u8 data[ETH_DATA_LEN];
};



int pool_size = 8;
module_param(pool_size, int, 0);


static void WILC_WFI_TxTimeout(struct net_device *dev);
static void (*WILC_WFI_Interrupt)(int, void *, struct pt_regs *);

/**
 *  @brief      WILC_WFI_SetupPool
 *  @details    Set up a device's packet pool.
 *  @param[in]  struct net_device *dev : Network Device Pointer
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_SetupPool(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	int i;
	struct WILC_WFI_packet *pkt;

	priv->ppool = NULL;
	for (i = 0; i < pool_size; i++) {
		pkt = kmalloc (sizeof (struct WILC_WFI_packet), GFP_KERNEL);
		if (pkt == NULL) {
			PRINT_D(RX_DBG, "Ran out of memory allocating packet pool\n");
			return;
		}
		pkt->dev = dev;
		pkt->next = priv->ppool;
		priv->ppool = pkt;
	}
}

/**
 *  @brief      WILC_WFI_TearDownPool
 *  @details    Internal cleanup function that's called after the network device
 *              driver is unregistered
 *  @param[in]  struct net_device *dev : Network Device Driver
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_TearDownPool(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	struct WILC_WFI_packet *pkt;

	while ((pkt = priv->ppool)) {
		priv->ppool = pkt->next;
		kfree (pkt);
		/* FIXME - in-flight packets ? */
	}
}

/**
 *  @brief      WILC_WFI_GetTxBuffer
 *  @details    Buffer/pool management
 *  @param[in]  net_device *dev : Network Device Driver Structure
 *  @return     struct WILC_WFI_packet
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
struct WILC_WFI_packet *WILC_WFI_GetTxBuffer(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	unsigned long flags;
	struct WILC_WFI_packet *pkt;

	spin_lock_irqsave(&priv->lock, flags);
	pkt = priv->ppool;
	priv->ppool = pkt->next;
	if (priv->ppool == NULL) {
		PRINT_INFO(RX_DBG, "Pool empty\n");
		netif_stop_queue(dev);
	}
	spin_unlock_irqrestore(&priv->lock, flags);
	return pkt;
}
/**
 *  @brief      WILC_WFI_ReleaseBuffer
 *  @details    Buffer/pool management
 *  @param[in]  WILC_WFI_packet *pkt : Structure holding in-flight packet
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_ReleaseBuffer(struct WILC_WFI_packet *pkt)
{
	unsigned long flags;
	struct WILC_WFI_priv *priv = netdev_priv(pkt->dev);

	spin_lock_irqsave(&priv->lock, flags);
	pkt->next = priv->ppool;
	priv->ppool = pkt;
	spin_unlock_irqrestore(&priv->lock, flags);
	if (netif_queue_stopped(pkt->dev) && pkt->next == NULL)
		netif_wake_queue(pkt->dev);
}

/**
 *  @brief      WILC_WFI_EnqueueBuf
 *  @details    Enqueuing packets in an RX buffer queue
 *  @param[in]  WILC_WFI_packet *pkt : Structure holding in-flight packet
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_EnqueueBuf(struct net_device *dev, struct WILC_WFI_packet *pkt)
{
	unsigned long flags;
	struct WILC_WFI_priv *priv = netdev_priv(dev);

	spin_lock_irqsave(&priv->lock, flags);
	pkt->next = priv->rx_queue;   /* FIXME - misorders packets */
	priv->rx_queue = pkt;
	spin_unlock_irqrestore(&priv->lock, flags);
}

/**
 *  @brief      WILC_WFI_DequeueBuf
 *  @details    Dequeuing packets from the RX buffer queue
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @return     WILC_WFI_packet *pkt : Structure holding in-flight pac
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
struct WILC_WFI_packet *WILC_WFI_DequeueBuf(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	struct WILC_WFI_packet *pkt;
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);
	pkt = priv->rx_queue;
	if (pkt != NULL)
		priv->rx_queue = pkt->next;
	spin_unlock_irqrestore(&priv->lock, flags);
	return pkt;
}
/**
 *  @brief      WILC_WFI_RxInts
 *  @details    Enable and disable receive interrupts.
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @param[in]	enable : Enable/Disable flag
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
static void WILC_WFI_RxInts(struct net_device *dev, int enable)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	priv->rx_int_enabled = enable;
}

/**
 *  @brief      WILC_WFI_Open
 *  @details    Open Network Device Driver, called when the network
 *              interface is opened. It starts the interface's transmit queue.
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @param[in]	enable : Enable/Disable flag
 *  @return     int : Returns 0 upon success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Open(struct net_device *dev)
{
	/* request_region(), request_irq(), ....  (like fops->open) */
	/*
	 * Assign the hardware address of the board: use "\0SNULx", where
	 * x is 0 or 1. The first byte is '\0' to avoid being a multicast
	 * address (the first byte of multicast addrs is odd).
	 */
	memcpy(dev->dev_addr, "\0WLAN0", ETH_ALEN);
	if (dev == WILC_WFI_devs[1])
		dev->dev_addr[ETH_ALEN - 1]++;  /* \0SNUL1 */

	WILC_WFI_InitHostInt(dev);
	netif_start_queue(dev);
	return 0;
}
/**
 *  @brief      WILC_WFI_Release
 *  @details    Release Network Device Driver, called when the network
 *              interface is stopped or brought down. This function marks
 *              the network driver as not being able to transmit
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @return     int : Return 0 on Success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Release(struct net_device *dev)
{
	/* release ports, irq and such -- like fops->close */

	netif_stop_queue(dev); /* can't transmit any more */

	return 0;
}
/**
 *  @brief      WILC_WFI_Config
 *  @details    Configuration changes (passed on by ifconfig)
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @param[in]	struct ifmap *map : Contains the ioctl implementation for the
 *              network driver.
 *  @return     int : Return 0 on Success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Config(struct net_device *dev, struct ifmap *map)
{
	if (dev->flags & IFF_UP) /* can't act on a running interface */
		return -EBUSY;

	/* Don't allow changing the I/O address */
	if (map->base_addr != dev->base_addr) {
		PRINT_D(RX_DBG, KERN_WARNING "WILC_WFI: Can't change I/O address\n");
		return -EOPNOTSUPP;
	}

	/* Allow changing the IRQ */
	if (map->irq != dev->irq) {
		dev->irq = map->irq;
		/* request_irq() is delayed to open-time */
	}

	/* ignore other fields */
	return 0;
}
/**
 *  @brief      WILC_WFI_Rx
 *  @details    Receive a packet: retrieve, encapsulate and pass over to upper
 *              levels
 *  @param[in]   net_device *dev : Network Device Driver Structure
 *  @param[in]	WILC_WFI_packet :
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_Rx(struct net_device *dev, struct WILC_WFI_packet *pkt)
{
	int i;
	struct sk_buff *skb;
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	s8 rssi;
	/*
	 * The packet has been retrieved from the transmission
	 * medium. Build an skb around it, so upper layers can handle it
	 */


	skb = dev_alloc_skb(pkt->datalen + 2);
	if (!skb) {
		if (printk_ratelimit())
			PRINT_D(RX_DBG, "WILC_WFI rx: low on mem - packet dropped\n");
		priv->stats.rx_dropped++;
		goto out;
	}
	skb_reserve(skb, 2);  /* align IP on 16B boundary */
	memcpy(skb_put(skb, pkt->datalen), pkt->data, pkt->datalen);

	if (priv->monitor_flag) {
		PRINT_INFO(RX_DBG, "In monitor device name %s\n", dev->name);
		priv = wiphy_priv(priv->dev->ieee80211_ptr->wiphy);
		PRINT_D(RX_DBG, "VALUE PASSED IN OF HRWD %p\n", priv->hWILCWFIDrv);
		/* host_int_get_rssi(priv->hWILCWFIDrv, &(rssi)); */
		if (INFO) {
			for (i = 14; i < skb->len; i++)
				PRINT_INFO(RX_DBG, "RXdata[%d] %02x\n", i, skb->data[i]);
		}
		WILC_WFI_monitor_rx(dev, skb);
		return;
	}
out:
	return;
}

/**
 *  @brief      WILC_WFI_Poll
 *  @details    The poll implementation
 *  @param[in]   struct napi_struct *napi :
 *  @param[in]	int budget :
 *  @return     int : Return 0 on Success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
static int WILC_WFI_Poll(struct napi_struct *napi, int budget)
{
	int npackets = 0;
	struct sk_buff *skb;
	struct WILC_WFI_priv  *priv = container_of(napi, struct WILC_WFI_priv, napi);
	struct net_device  *dev =  priv->dev;
	struct WILC_WFI_packet *pkt;

	while (npackets < budget && priv->rx_queue) {
		pkt = WILC_WFI_DequeueBuf(dev);
		skb = dev_alloc_skb(pkt->datalen + 2);
		if (!skb) {
			if (printk_ratelimit())
				PRINT_D(RX_DBG, "WILC_WFI: packet dropped\n");
			priv->stats.rx_dropped++;
			WILC_WFI_ReleaseBuffer(pkt);
			continue;
		}
		skb_reserve(skb, 2);  /* align IP on 16B boundary */
		memcpy(skb_put(skb, pkt->datalen), pkt->data, pkt->datalen);
		skb->dev = dev;
		skb->protocol = eth_type_trans(skb, dev);
		skb->ip_summed = CHECKSUM_UNNECESSARY;  /* don't check it */
		netif_receive_skb(skb);
		/* Maintain stats */
		npackets++;
		WILC_WFI_update_stats(priv->dev->ieee80211_ptr->wiphy, pkt->datalen, WILC_WFI_RX_PKT);
		WILC_WFI_ReleaseBuffer(pkt);
	}
	/* If we processed all packets, we're done; tell the kernel and re-enable ints */
	if (npackets < budget) {
		napi_complete(napi);
		WILC_WFI_RxInts(dev, 1);
	}
	return npackets;
}

/**
 *  @brief      WILC_WFI_Poll
 *  @details    The typical interrupt entry point
 *  @param[in]   struct napi_struct *napi :
 *  @param[in]	int budget :
 *  @return     int : Return 0 on Success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
static void WILC_WFI_RegularInterrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	int statusword;
	struct WILC_WFI_priv *priv;
	struct WILC_WFI_packet *pkt = NULL;
	/*
	 * As usual, check the "device" pointer to be sure it is
	 * really interrupting.
	 * Then assign "struct device *dev"
	 */
	struct net_device *dev = (struct net_device *)dev_id;
	/* ... and check with hw if it's really ours */

	/* paranoid */
	if (!dev)
		return;

	/* Lock the device */
	priv = netdev_priv(dev);
	spin_lock(&priv->lock);

	/* retrieve statusword: real netdevices use I/O instructions */
	statusword = priv->status;
	priv->status = 0;
	if (statusword & WILC_WFI_RX_INTR) {
		/* send it to WILC_WFI_rx for handling */
		pkt = priv->rx_queue;
		if (pkt) {
			priv->rx_queue = pkt->next;
			WILC_WFI_Rx(dev, pkt);
		}
	}
	if (statusword & WILC_WFI_TX_INTR) {
		/* a transmission is over: free the skb */
		WILC_WFI_update_stats(priv->dev->ieee80211_ptr->wiphy, priv->tx_packetlen, WILC_WFI_TX_PKT);
		dev_kfree_skb(priv->skb);
	}

	/* Unlock the device and we are done */
	spin_unlock(&priv->lock);
	if (pkt)
		WILC_WFI_ReleaseBuffer(pkt);  /* Do this outside the lock! */
	return;
}
/**
 *  @brief      WILC_WFI_NapiInterrupt
 *  @details    A NAPI interrupt handler
 *  @param[in]   irq:
 *  @param[in]	dev_id:
 *  @param[in]	pt_regs:
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
static void WILC_WFI_NapiInterrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	int statusword;
	struct WILC_WFI_priv *priv;

	/*
	 * As usual, check the "device" pointer for shared handlers.
	 * Then assign "struct device *dev"
	 */
	struct net_device *dev = (struct net_device *)dev_id;
	/* ... and check with hw if it's really ours */

	/* paranoid */
	if (!dev)
		return;

	/* Lock the device */
	priv = netdev_priv(dev);
	spin_lock(&priv->lock);

	/* retrieve statusword: real netdevices use I/O instructions */
	statusword = priv->status;
	priv->status = 0;
	if (statusword & WILC_WFI_RX_INTR) {
		WILC_WFI_RxInts(dev, 0);   /* Disable further interrupts */
		napi_schedule(&priv->napi);
	}
	if (statusword & WILC_WFI_TX_INTR) {
		/* a transmission is over: free the skb */

		WILC_WFI_update_stats(priv->dev->ieee80211_ptr->wiphy, priv->tx_packetlen, WILC_WFI_TX_PKT);
		dev_kfree_skb(priv->skb);
	}

	/* Unlock the device and we are done */
	spin_unlock(&priv->lock);
	return;
}

/**
 *  @brief      MI_WFI_HwTx
 *  @details    Transmit a packet (low level interface)
 *  @param[in]   buf:
 *  @param[in]	len:
 *  @param[in]	net_device *dev:
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_HwTx(char *buf, int len, struct net_device *dev)
{
	/*
	 * This function deals with hw details. This interface loops
	 * back the packet to the other WILC_WFI interface (if any).
	 * In other words, this function implements the WILC_WFI behaviour,
	 * while all other procedures are rather device-independent
	 */
	struct iphdr *ih;
	struct net_device *dest;
	struct WILC_WFI_priv *priv;
	u32 *saddr, *daddr;
	struct WILC_WFI_packet *tx_buffer;


	/* I am paranoid. Ain't I? */
	if (len < sizeof(struct ethhdr) + sizeof(struct iphdr)) {
		PRINT_D(RX_DBG, "WILC_WFI: Hmm... packet too short (%i octets)\n",
			len);
		return;
	}

	if (0) {  /* enable this conditional to look at the data */
		int i;
		PRINT_D(RX_DBG, "len is %i", len);
		for (i = 14; i < len; i++)
			PRINT_D(RX_DBG, "TXdata[%d] %02x\n", i, buf[i] & 0xff);
		/*   PRINT_D(RX_DBG, "\n"); */
	}
	/*
	 * Ethhdr is 14 bytes, but the kernel arranges for iphdr
	 * to be aligned (i.e., ethhdr is unaligned)
	 */
	ih = (struct iphdr *)(buf + sizeof(struct ethhdr));
	saddr = &ih->saddr;
	daddr = &ih->daddr;

	((u8 *)saddr)[2] ^= 1;  /* change the third octet (class C) */
	((u8 *)daddr)[2] ^= 1;

	ih->check = 0;          /* and rebuild the checksum (ip needs it) */
	ih->check = ip_fast_csum((unsigned char *)ih, ih->ihl);


	if (dev == WILC_WFI_devs[0])
		PRINT_D(RX_DBG, "%08x:%05i --> %08x:%05i\n",
			ntohl(ih->saddr), ntohs(((struct tcphdr *)(ih + 1))->source),
			ntohl(ih->daddr), ntohs(((struct tcphdr *)(ih + 1))->dest));
	else
		PRINT_D(RX_DBG, "%08x:%05i <-- %08x:%05i\n",
			ntohl(ih->daddr), ntohs(((struct tcphdr *)(ih + 1))->dest),
			ntohl(ih->saddr), ntohs(((struct tcphdr *)(ih + 1))->source));

	/*
	 * Ok, now the packet is ready for transmission: first simulate a
	 * receive interrupt on the twin device, then  a
	 * transmission-done on the transmitting device
	 */
	dest = WILC_WFI_devs[dev == WILC_WFI_devs[0] ? 1 : 0];
	priv = netdev_priv(dest);

	tx_buffer = WILC_WFI_GetTxBuffer(dev);
	tx_buffer->datalen = len;
	memcpy(tx_buffer->data, buf, len);
	WILC_WFI_EnqueueBuf(dest, tx_buffer);
	if (priv->rx_int_enabled) {
		priv->status |= WILC_WFI_RX_INTR;
		WILC_WFI_Interrupt(0, dest, NULL);
	}

	priv = netdev_priv(dev);
	priv->tx_packetlen = len;
	priv->tx_packetdata = buf;
	priv->status |= WILC_WFI_TX_INTR;
	if (lockup && ((priv->stats.tx_packets + 1) % lockup) == 0) {
		/* Simulate a dropped transmit interrupt */
		netif_stop_queue(dev);
		PRINT_D(RX_DBG, "Simulate lockup at %ld, txp %ld\n", jiffies,
			(unsigned long) priv->stats.tx_packets);
	} else
		WILC_WFI_Interrupt(0, dev, NULL);

}

/**
 *  @brief      WILC_WFI_Tx
 *  @details    Transmit a packet (called by the kernel)
 *  @param[in]   sk_buff *skb:
 *  @param[in]	net_device *dev:
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Tx(struct sk_buff *skb, struct net_device *dev)
{
	int len;
	char *data, shortpkt[ETH_ZLEN];
	struct WILC_WFI_priv *priv = netdev_priv(dev);

	/* priv = wiphy_priv(priv->dev->ieee80211_ptr->wiphy); */

	/*  if(priv->monitor_flag) */
	/*	 mac80211_hwsim_monitor_rx(skb); */


	data = skb->data;
	len = skb->len;

	if (len < ETH_ZLEN) {
		memset(shortpkt, 0, ETH_ZLEN);
		memcpy(shortpkt, skb->data, skb->len);
		len = ETH_ZLEN;
		data = shortpkt;
	}
	dev->trans_start = jiffies;  /* save the timestamp */

	/* Remember the skb, so we can free it at interrupt time */
	priv->skb = skb;

	/* actual deliver of data is device-specific, and not shown here */
	WILC_WFI_HwTx(data, len, dev);

	return 0;  /* Our simple device can not fail */
}

/**
 *  @brief      WILC_WFI_TxTimeout
 *  @details    Deal with a transmit timeout.
 *  @param[in]	net_device *dev:
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_TxTimeout(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);

	PRINT_D(RX_DBG, "Transmit timeout at %ld, latency %ld\n", jiffies,
		jiffies - dev->trans_start);
	/* Simulate a transmission interrupt to get things moving */
	priv->status = WILC_WFI_TX_INTR;
	WILC_WFI_Interrupt(0, dev, NULL);
	priv->stats.tx_errors++;
	netif_wake_queue(dev);
	return;
}

/**
 *  @brief      WILC_WFI_Ioctl
 *  @details    Ioctl commands
 *  @param[in]	net_device *dev:
 *  @param[in]	ifreq *rq
 *  @param[in]	cmd:
 *  @return     int : Return 0 on Success
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
	PRINT_D(RX_DBG, "ioctl\n");
	return 0;
}

/**
 *  @brief      WILC_WFI_Stat
 *  @details    Return statistics to the caller
 *  @param[in]	net_device *dev:
 *  @return     WILC_WFI_Stats : Return net_device_stats stucture with the
 *              network device driver private data contents.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
struct net_device_stats *WILC_WFI_Stats(struct net_device *dev)
{
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	return &priv->stats;
}

/**
 *  @brief      WILC_WFI_RebuildHeader
 *  @details    This function is called to fill up an eth header, since arp is not
 *              available on the interface
 *  @param[in]	sk_buff *skb:
 *  @return     int : Return 0 on Success
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_RebuildHeader(struct sk_buff *skb)
{
	struct ethhdr *eth = (struct ethhdr *) skb->data;
	struct net_device *dev = skb->dev;

	memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
	memcpy(eth->h_dest, dev->dev_addr, dev->addr_len);
	eth->h_dest[ETH_ALEN - 1]   ^= 0x01;  /* dest is us xor 1 */
	return 0;
}
/**
 *  @brief      WILC_WFI_RebuildHeader
 *  @details    This function is called to fill up an eth header, since arp is not
 *              available on the interface
 *  @param[in]	sk_buff *skb:
 *  @param[in]	struct net_device *dev:
 *  @param[in]   unsigned short type:
 *  @param[in]   const void *saddr,
 *  @param[in]   const void *daddr:
 *  @param[in]          unsigned int len
 *  @return     int : Return 0 on Success
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_Header(struct sk_buff *skb, struct net_device *dev,
		    unsigned short type, const void *daddr, const void *saddr,
		    unsigned int len)
{
	struct ethhdr *eth = (struct ethhdr *)skb_push(skb, ETH_HLEN);

	eth->h_proto = htons(type);
	memcpy(eth->h_source, saddr ? saddr : dev->dev_addr, dev->addr_len);
	memcpy(eth->h_dest,   daddr ? daddr : dev->dev_addr, dev->addr_len);
	eth->h_dest[ETH_ALEN - 1]   ^= 0x01;  /* dest is us xor 1 */
	return dev->hard_header_len;
}

/**
 *  @brief      WILC_WFI_ChangeMtu
 *  @details    The "change_mtu" method is usually not needed.
 *              If you need it, it must be like this.
 *  @param[in]	net_device *dev : Network Device Driver Structure
 *  @param[in]	new_mtu :
 *  @return     int : Returns 0 on Success.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_ChangeMtu(struct net_device *dev, int new_mtu)
{
	unsigned long flags;
	struct WILC_WFI_priv *priv = netdev_priv(dev);
	spinlock_t *lock = &priv->lock;

	/* check ranges */
	if ((new_mtu < 68) || (new_mtu > 1500))
		return -EINVAL;
	/*
	 * Do anything you need, and the accept the value
	 */
	spin_lock_irqsave(lock, flags);
	dev->mtu = new_mtu;
	spin_unlock_irqrestore(lock, flags);
	return 0;  /* success */
}

static const struct header_ops WILC_WFI_header_ops = {
	.create  = WILC_WFI_Header,
	.rebuild = WILC_WFI_RebuildHeader,
	.cache   = NULL,   /* disable caching */
};


static const struct net_device_ops WILC_WFI_netdev_ops = {
	.ndo_open = WILC_WFI_Open,
	.ndo_stop = WILC_WFI_Release,
	.ndo_set_config = WILC_WFI_Config,
	.ndo_start_xmit = WILC_WFI_Tx,
	.ndo_do_ioctl = WILC_WFI_Ioctl,
	.ndo_get_stats = WILC_WFI_Stats,
	.ndo_change_mtu = WILC_WFI_ChangeMtu,
	.ndo_tx_timeout = WILC_WFI_TxTimeout,
};

/**
 *  @brief      WILC_WFI_Init
 *  @details    The init function (sometimes called probe).
 *              It is invoked by register_netdev()
 *  @param[in]	net_device *dev:
 *  @return     NONE
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
void WILC_WFI_Init(struct net_device *dev)
{
	struct WILC_WFI_priv *priv;


	/*
	 * Then, assign other fields in dev, using ether_setup() and some
	 * hand assignments
	 */
	ether_setup(dev);  /* assign some of the fields */
	/* 1- Allocate space */

	dev->netdev_ops      = &WILC_WFI_netdev_ops;
	dev->header_ops      = &WILC_WFI_header_ops;
	dev->watchdog_timeo = timeout;
	/* keep the default flags, just add NOARP */
	dev->flags           |= IFF_NOARP;
	dev->features        |= NETIF_F_NO_CSUM;
	/*
	 * Then, initialize the priv field. This encloses the statistics
	 * and a few private fields.
	 */
	priv = netdev_priv(dev);
	memset(priv, 0, sizeof(struct WILC_WFI_priv));
	priv->dev = dev;
	netif_napi_add(dev, &priv->napi, WILC_WFI_Poll, 2);
	/* The last parameter above is the NAPI "weight". */
	spin_lock_init(&priv->lock);
	WILC_WFI_RxInts(dev, 1);           /* enable receive interrupts */
	WILC_WFI_SetupPool(dev);
}

/**
 *  @brief      WILC_WFI_Stat
 *  @details    Return statistics to the caller
 *  @param[in]	net_device *dev:
 *  @return     WILC_WFI_Stats : Return net_device_stats stucture with the
 *              network device driver private data contents.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */

void WILC_WFI_Cleanup(void)
{
	int i;
	struct WILC_WFI_priv *priv[2];

	/*if(hwsim_mon!=NULL)
	 * {
	 *      PRINT_D(RX_DBG, "Freeing monitor interface\n");
	 *      unregister_netdev(hwsim_mon);
	 *      free_netdev(hwsim_mon);
	 * }*/
	for (i = 0; i < 2; i++) {
		priv[i] = netdev_priv(WILC_WFI_devs[i]);

		if (WILC_WFI_devs[i]) {
			PRINT_D(RX_DBG, "Unregistering\n");
			unregister_netdev(WILC_WFI_devs[i]);
			WILC_WFI_TearDownPool(WILC_WFI_devs[i]);
			free_netdev(WILC_WFI_devs[i]);
			PRINT_D(RX_DBG, "[NETDEV]Stopping interface\n");
			WILC_WFI_DeInitHostInt(WILC_WFI_devs[i]);
			WILC_WFI_WiphyFree(WILC_WFI_devs[i]);
		}

	}
	/* unregister_netdev(hwsim_mon); */
	WILC_WFI_deinit_mon_interface();
	return;
}


void StartConfigSim(void);







/**
 *  @brief      WILC_WFI_Stat
 *  @details    Return statistics to the caller
 *  @param[in]	net_device *dev:
 *  @return     WILC_WFI_Stats : Return net_device_stats stucture with the
 *              network device driver private data contents.
 *  @author	mdaftedar
 *  @date	01 MAR 2012
 *  @version	1.0
 */
int WILC_WFI_InitModule(void)
{

	int result, i, ret = -ENOMEM;
	struct WILC_WFI_priv *priv[2], *netpriv;
	struct wireless_dev *wdev;
	WILC_WFI_Interrupt = use_napi ? WILC_WFI_NapiInterrupt : WILC_WFI_RegularInterrupt;
	char buf[IFNAMSIZ];

	for (i = 0; i < 2; i++)	{

		/* Allocate the net devices */
		WILC_WFI_devs[i] = alloc_netdev(sizeof(struct WILC_WFI_priv), "wlan%d",
						WILC_WFI_Init);
		if (WILC_WFI_devs[i] == NULL)
			goto out;
		/* priv[i] = netdev_priv(WILC_WFI_devs[i]); */

		wdev = WILC_WFI_WiphyRegister(WILC_WFI_devs[i]);
		WILC_WFI_devs[i]->ieee80211_ptr = wdev;
		netpriv = netdev_priv(WILC_WFI_devs[i]);
		netpriv->dev->ieee80211_ptr = wdev;
		netpriv->dev->ml_priv = netpriv;
		wdev->netdev = netpriv->dev;

		/*Registering the net device*/
		result = register_netdev(WILC_WFI_devs[i]);
		if (result)
			PRINT_D(RX_DBG, "WILC_WFI: error %i registering device \"%s\"\n",
				result, WILC_WFI_devs[i]->name);
		else
			ret = 0;
	}


	/*init atmel driver */
	priv[0] = netdev_priv(WILC_WFI_devs[0]);
	priv[1] = netdev_priv(WILC_WFI_devs[1]);

	if (priv[1]->dev->ieee80211_ptr->wiphy->interface_modes && BIT(NL80211_IFTYPE_MONITOR))	{
		/* snprintf(buf, IFNAMSIZ, "mon.%s",  priv[1]->dev->name); */
		/*	WILC_WFI_init_mon_interface(); */
		/*	priv[1]->monitor_flag = 1; */

	}
	priv[0]->bCfgScanning = false;
	priv[0]->u32RcvdChCount = 0;

	WILC_memset(priv[0]->au8AssociatedBss, 0xFF, ETH_ALEN);


	/* ret = host_int_init(&priv[0]->hWILCWFIDrv); */
	/*copy handle to the other driver*/
	/* priv[1]->hWILCWFIDrv = priv[0]->hWILCWFIDrv; */
	if (ret) {
		PRINT_ER("Error Init Driver\n");
	}


out:
	if (ret)
		WILC_WFI_Cleanup();
	return ret;


}


module_init(WILC_WFI_InitModule);
module_exit(WILC_WFI_Cleanup);

#endif