/****************************************************************************
 * wireless/ieee802154/mac802154_netdev.c
 *
 *   Copyright (C) 2017-2018 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdint.h>
#include <stdbool.h>
#include <time.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>

#include <arpa/inet.h>

#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <nuttx/kmalloc.h>
#include <nuttx/signal.h>
#include <nuttx/wdog.h>
#include <nuttx/wqueue.h>
#include <nuttx/mm/iob.h>
#include <nuttx/net/arp.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/radiodev.h>
#include <nuttx/net/ieee802154.h>
#include <nuttx/net/sixlowpan.h>
#include <nuttx/wireless/ieee802154/ieee802154_mac.h>

#include "mac802154.h"

#if defined(CONFIG_NET_6LOWPAN) || defined(CONFIG_NET_IEEE802154)

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* If processing is not done at the interrupt level, then work queue support
 * is required.
 */

#if !defined(CONFIG_SCHED_WORKQUEUE)
#  error Work queue support is required in this configuration (CONFIG_SCHED_WORKQUEUE)
#endif

/* The low priority work queue is preferred.  If it is not enabled, LPWORK
 * will be the same as HPWORK.
 *
 * NOTE:  However, the network should NEVER run on the high priority work
 * queue!  That queue is intended only to service short back end interrupt
 * processing that never suspends.  Suspending the high priority work queue
 * may bring the system to its knees!
 */

#define WPANWORK LPWORK

/* CONFIG_IEEE802154_NETDEV_NINTERFACES determines the number of physical interfaces
 * that will be supported.
 */

#ifndef CONFIG_IEEE802154_NETDEV_NINTERFACES
# define CONFIG_IEEE802154_NETDEV_NINTERFACES 1
#endif

/* Preferred address size */

#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
#  define MACNET_ADDRSIZE IEEE802154_EADDRSIZE
#else
#  define MACNET_ADDRSIZE IEEE802154_SADDRSIZE
#endif

/* Frame size */

#if defined(CONFIG_NET_IEEE802154_FRAMELEN)
#  define MACNET_FRAMELEN CONFIG_NET_IEEE802154_FRAMELEN
#else
#  define MACNET_FRAMELEN IEEE802154_MAX_PHY_PACKET_SIZE
#endif

#if (CONFIG_MAC802154_NTXDESC < CONFIG_IOB_NBUFFERS)
#  warning "CONFIG_MAC802154_NTXDESC should probably be equal to" \
           "CONFIG_IOB_NBUFFERS to avoid waiting on req_data"
#endif

/* TX poll delay = 1 seconds. CLK_TCK is the number of clock ticks per second */

#define TXPOLL_WDDELAY   (1*CLK_TCK)

/****************************************************************************
 * Private Types
 ****************************************************************************/

/* This is our private version of the MAC callback structure */

struct macnet_callback_s
{
  /* This holds the information visible to the MAC layer */

  struct mac802154_maccb_s mc_cb;      /* Interface understood by the MAC layer */
  FAR struct macnet_driver_s *mc_priv; /* Our priv data */
};

/* The macnet_driver_s encapsulates all state information for a single
 * IEEE802.15.4 MAC interface.
 */

struct macnet_driver_s
{
  /* This holds the information visible to the NuttX network */

  struct radio_driver_s md_dev;   /* Interface understood by the network */
                                  /* Cast compatible with struct macnet_driver_s */

  /* For internal use by this driver */

  sem_t md_exclsem;               /* Exclusive access to struct */
  struct macnet_callback_s md_cb; /* Callback information */
  MACHANDLE md_mac;               /* Contained MAC interface */
  bool md_bifup;                  /* true:ifup false:ifdown */
  WDOG_ID md_txpoll;              /* TX poll timer */
  struct work_s md_pollwork;      /* Defer poll work to the work queue */

  /* Hold a list of events */

  bool md_enableevents : 1;       /* Are events enabled? */
  bool md_eventpending : 1;       /* Is there a get event using the semaphore? */
  sem_t md_eventsem;              /* Signaling semaphore for waiting get event */
  sq_queue_t primitive_queue;     /* For holding primitives to pass along */

  /* MAC Service notification information */

  bool    md_notify_registered;
  pid_t   md_notify_pid;
  struct sigevent md_notify_event;
  struct sigwork_s md_notify_work;

#ifdef CONFIG_NET_6LOWPAN
  struct sixlowpan_reassbuf_s md_iobuffer;
#endif
};

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

/* Utility functions ********************************************************/

static int macnet_update_nvaddr(FAR struct net_driver_s *dev);
static inline void macnet_netmask(FAR struct net_driver_s *dev);

/* IEE802.15.4 MAC callback functions ***************************************/

static int  macnet_notify(FAR struct mac802154_maccb_s *maccb,
                          FAR struct ieee802154_primitive_s *primitive);
static int  macnet_rxframe(FAR struct macnet_driver_s *maccb,
                           FAR struct ieee802154_data_ind_s *ind);

/* Network interface support ************************************************/
/* Common TX logic */

static int  macnet_txpoll_callback(FAR struct net_driver_s *dev);
static void macnet_txpoll_work(FAR void *arg);
static void macnet_txpoll_expiry(int argc, wdparm_t arg, ...);

/* IOCTL support */

#ifdef CONFIG_NET_STARPOINT
#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
static int macnet_coord_eaddr(FAR struct radio_driver_s *radio,
                              FAR uint8_t *eaddr);
#else
static int macnet_coord_saddr(FAR struct radio_driver_s *radio,
                              FAR uint8_t *saddr);
#endif
#endif

/* NuttX callback functions */

static int  macnet_ifup(FAR struct net_driver_s *dev);
static int  macnet_ifdown(FAR struct net_driver_s *dev);

static void macnet_txavail_work(FAR void *arg);
static int  macnet_txavail(FAR struct net_driver_s *dev);

#ifdef CONFIG_NET_MCASTGROUP
static int  macnet_addmac(FAR struct net_driver_s *dev,
              FAR const uint8_t *mac);
static int  macnet_rmmac(FAR struct net_driver_s *dev,
              FAR const uint8_t *mac);
#endif
#ifdef CONFIG_NETDEV_IOCTL
static int  macnet_ioctl(FAR struct net_driver_s *dev, int cmd,
              unsigned long arg);
#endif
static int macnet_get_mhrlen(FAR struct radio_driver_s *netdev,
              FAR const void *meta);
static int macnet_req_data(FAR struct radio_driver_s *netdev,
              FAR const void *meta, FAR struct iob_s *framelist);
static int macnet_properties(FAR struct radio_driver_s *netdev,
              FAR struct radiodev_properties_s *properties);

/****************************************************************************
 * Private Data
 ****************************************************************************/

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: macnet_update_nvaddr
 *
 * Description:
 *   Advertise the MAC and IPv6 address for this node.
 *
 *
 ****************************************************************************/

static int macnet_update_nvaddr(FAR struct net_driver_s *dev)
{
  FAR struct macnet_driver_s *priv;
  union ieee802154_macarg_u arg;
  int ret;

  DEBUGASSERT(dev != NULL && dev->d_private != NULL);
  priv = (FAR struct macnet_driver_s *)dev->d_private;

#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR

  /* Get the eaddr from the MAC */

  arg.getreq.attr = IEEE802154_ATTR_MAC_EADDR;
  ret = mac802154_ioctl(priv->md_mac, MAC802154IOC_MLME_GET_REQUEST,
                        (unsigned long)((uintptr_t)&arg));
  if (ret < 0)
    {
      wlerr("ERROR: MAC802154IOC_MLME_GET_REQUEST failed: %d\n", ret);
      return ret;
    }
  else
    {
      IEEE802154_EADDRCOPY(dev->d_mac.radio.nv_addr, arg.getreq.attrval.mac.eaddr);
      dev->d_mac.radio.nv_addrlen = IEEE802154_EADDRSIZE;
      return OK;
    }

#else
  uint8_t *saddr;

  /* Get the saddr from the MAC */

  arg.getreq.attr = IEEE802154_ATTR_MAC_SADDR;
  ret = mac802154_ioctl(priv->md_mac, MAC802154IOC_MLME_GET_REQUEST,
                        (unsigned long)((uintptr_t)&arg));
  if (ret < 0)
    {
      wlerr("ERROR: MAC802154IOC_MLME_GET_REQUEST failed: %d\n", ret);
      return ret;
    }
  else
    {
      /* Set the MAC address as the saddr */

      saddr = arg.getreq.attrval.mac.saddr;

      /* Network layers expect address in Network Order (Big Endian) */

      dev->d_mac.radio.nv_addr[0] = saddr[1];
      dev->d_mac.radio.nv_addr[1] = saddr[0];

      dev->d_mac.radio.nv_addrlen = IEEE802154_SADDRSIZE;
      return OK;
    }
#endif
}

/****************************************************************************
 * Name: macnet_netmask
 *
 * Description:
 *   Create a netmask of a MAC-based IP address which may be based on either
 *   the IEEE 802.15.14 short or extended address of the MAC.
 *
 *    128  112  96   80    64   48   32   16
 *    ---- ---- ---- ----  ---- ---- ---- ----
 *    fe80 0000 0000 0000  0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
 *    fe80 0000 0000 0000  xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
 *
 ****************************************************************************/

static inline void macnet_netmask(FAR struct net_driver_s *dev)
{
  dev->d_ipv6netmask[0]  = 0xffff;
  dev->d_ipv6netmask[1]  = 0xffff;
  dev->d_ipv6netmask[2]  = 0xffff;
  dev->d_ipv6netmask[3]  = 0xffff;
#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
  dev->d_ipv6netmask[4]  = 0;
  dev->d_ipv6netmask[5]  = 0;
  dev->d_ipv6netmask[6]  = 0;
  dev->d_ipv6netmask[7]  = 0;
#else
  dev->d_ipv6netmask[4]  = 0xffff;
  dev->d_ipv6netmask[5]  = 0xffff;
  dev->d_ipv6netmask[6]  = 0xffff;
  dev->d_ipv6netmask[7]  = 0;
#endif
}

/****************************************************************************
 * Name: macnet_notify
 *
 * Description:
 *
 ****************************************************************************/

static int macnet_notify(FAR struct mac802154_maccb_s *maccb,
                         FAR struct ieee802154_primitive_s *primitive)
{
  FAR struct macnet_callback_s *cb =
    (FAR struct macnet_callback_s *)maccb;
  FAR struct macnet_driver_s *priv;

  DEBUGASSERT(cb != NULL && cb->mc_priv != NULL);
  priv = cb->mc_priv;

  /* Handle the special case for data indications or "incoming frames" */

  if (primitive->type == IEEE802154_PRIMITIVE_IND_DATA)
    {
      return macnet_rxframe(priv, &primitive->u.dataind);
    }

  /* If there is a registered notification receiver, queue the event and signal
   * the receiver. Events should be popped from the queue from the application
   * at a reasonable rate in order for the MAC layer to be able to allocate new
   * notifications.
   */

  if (priv->md_enableevents)
    {
      /* Get exclusive access to the driver structure.  We don't care about any
       * signals so if we see one, just go back to trying to get access again
       */

      while (nxsem_wait(&priv->md_exclsem) < 0);

      sq_addlast((FAR sq_entry_t *)primitive, &priv->primitive_queue);

      /* Check if there is a read waiting for data */

      if (priv->md_eventpending)
        {
          /* Wake the thread waiting for the data transmission */

          priv->md_eventpending = false;
          nxsem_post(&priv->md_eventsem);
        }

      if (priv->md_notify_registered)
        {
          priv->md_notify_event.sigev_value.sival_int = primitive->type;
          nxsig_notification(priv->md_notify_pid, &priv->md_notify_event,
                             SI_QUEUE, &priv->md_notify_work);
        }

      nxsem_post(&priv->md_exclsem);
      return OK;
    }

  /* By returning a negative value, we let the MAC know that we don't want the
   * primitive and it will free it for us
   */

  return -1;
}

/****************************************************************************
 * Name: macnet_rxframe
 *
 * Description:
 *   Handle received frames forward by the IEEE 802.15.4 MAC.
 *
 * Returned Value:
 *   Zero (OK) is returned on success; a negated errno value is returned on
 *   any failure.  On success, the ind and its contained iob will be freed.
 *   The ind will be intact if this function returns a failure.
 *
 ****************************************************************************/

static int macnet_rxframe(FAR struct macnet_driver_s *priv,
                          FAR struct ieee802154_data_ind_s *ind)
{
  FAR struct iob_s *iob;
  int ret;

  /* Ignore the frame if the network is not up */

  if (!priv->md_bifup)
    {
      wlwarn("WARNING: Dropped... Network is down\n");
      return -ENETDOWN;
    }

  /* Peek the IOB contained the frame in the struct ieee802154_data_ind_s */

  DEBUGASSERT(priv != NULL && ind != NULL && ind->frame != NULL);
  iob = ind->frame;

  /* Remove the IOB containing the frame. */

  ind->frame = NULL;

  net_lock();

  /* Transfer the frame to the network logic */

#ifdef CONFIG_NET_IEEE802154
  /* Invoke the PF_IEEE802154 tap first.  If the frame matches
   * with a connected PF_IEEE802145 socket, it will take the
   * frame and return success.
   */

  ret = ieee802154_input(&priv->md_dev, iob, (FAR void *)ind);
  if (ret < 0)
#endif
#ifdef CONFIG_NET_6LOWPAN
    {
      /* If the frame is not a 6LoWPAN frame, then return an error.  The
       * first byte following the MAC head at the io_offset should be a
       * valid IPHC header.
       */

      if ((iob->io_data[iob->io_offset] & SIXLOWPAN_DISPATCH_NALP_MASK) ==
          SIXLOWPAN_DISPATCH_NALP)
        {
          wlwarn("WARNING: Dropped... Not a 6LoWPAN frame: %02x\n",
                 iob->io_data[iob->io_offset]);
          ret = -EINVAL;
        }
      else
        {
          /* Make sure the our single packet buffer is attached */

          priv->md_dev.r_dev.d_buf = priv->md_iobuffer.rb_buf;

          /* And give the packet to 6LoWPAN */

          ret = sixlowpan_input(&priv->md_dev, iob, (FAR void *)ind);
        }
    }

  if (ret < 0)
#endif
    {
      net_unlock();
      ind->frame = iob;
      return ret;
    }

  /* Increment statistics */

  NETDEV_RXPACKETS(&priv->md_dev.r_dev);
  NETDEV_RXIPV6(&priv->md_dev.r_dev);

  net_unlock();

  /* sixlowpan_input() will free the IOB, but we must free the struct
   * ieee802154_primitive_s container here.
   */

  ieee802154_primitive_free((FAR struct ieee802154_primitive_s *)ind);
  return OK;
}

/****************************************************************************
 * Name: macnet_txpoll_callback
 *
 * Description:
 *   The transmitter is available, check if the network has any outgoing
 *   packets ready to send.  This is a callback from devif_poll().
 *   devif_poll() may be called:
 *
 *   1. When the preceding TX packet send is complete,
 *   2. When the preceding TX packet send timesout and the interface is reset
 *   3. During normal TX polling
 *
 * Input Parameters:
 *   dev - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   OK on success; a negated errno on failure
 *
 * Assumptions:
 *   The network is locked.
 *
 ****************************************************************************/

static int macnet_txpoll_callback(FAR struct net_driver_s *dev)
{
  /* If zero is returned, the polling will continue until all connections have
   * been examined.
   */

  return 0;
}

/****************************************************************************
 * Name: macnet_txpoll_work
 *
 * Description:
 *   Perform periodic polling from the worker thread
 *
 * Input Parameters:
 *   arg - The argument passed when work_queue() as called.
 *
 * Returned Value:
 *   OK on success
 *
 * Assumptions:
 *   The network is locked.
 *
 ****************************************************************************/

static void macnet_txpoll_work(FAR void *arg)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)arg;

  /* Lock the network and serialize driver operations if necessary.
   * NOTE: Serialization is only required in the case where the driver work
   * is performed on an LP worker thread and where more than one LP worker
   * thread has been configured.
   */

  net_lock();

#ifdef CONFIG_NET_6LOWPAN
  /* Make sure the our single packet buffer is attached */

  priv->md_dev.r_dev.d_buf = priv->md_iobuffer.rb_buf;
#endif

  /* Then perform the poll */

  (void)devif_timer(&priv->md_dev.r_dev, macnet_txpoll_callback);

  /* Setup the watchdog poll timer again */

  (void)wd_start(priv->md_txpoll, TXPOLL_WDDELAY, macnet_txpoll_expiry, 1,
                 (wdparm_t)priv);
  net_unlock();
}

/****************************************************************************
 * Name: macnet_txpoll_expiry
 *
 * Description:
 *   Periodic timer handler.  Called from the timer interrupt handler.
 *
 * Input Parameters:
 *   argc - The number of available arguments
 *   arg  - The first argument
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *   Global interrupts are disabled by the watchdog logic.
 *
 ****************************************************************************/

static void macnet_txpoll_expiry(int argc, wdparm_t arg, ...)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)arg;

  /* Schedule to perform the interrupt processing on the worker thread. */

  work_queue(WPANWORK, &priv->md_pollwork, macnet_txpoll_work, priv, 0);
}

/****************************************************************************
 * Name: macnet_coord_eaddr
 *
 * Description:
 *   Get the extended address of the PAN coordinator.
 *
 * Input Parameters:
 *   radio - Reference to a radio network driver state instance.
 *   eaddr - The location in which to return the extended address.
 *
 * Returned Value:
 *   Zero (OK) on success; a negated errno value on failure.
 *
 ****************************************************************************/

#if defined(CONFIG_NET_STARPOINT) && defined(CONFIG_NET_6LOWPAN_EXTENDEDADDR)
static int macnet_coord_eaddr(FAR struct radio_driver_s *radio,
                              FAR uint8_t *eaddr)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)radio;
  union ieee802154_macarg_u arg;
  int ret;

  arg.getreq.attr = IEEE802154_ATTR_MAC_COORD_EADDR ;
  ret = mac802154_ioctl(priv->md_mac, MAC802154IOC_MLME_GET_REQUEST,
                        (unsigned long)((uintptr_t)&arg));
  if (ret < 0)
    {
      nerr("ERROR: MAC802154IOC_MLME_GET_REQUEST failed: %d\n", ret);
      return ret;
    }

  IEEE802154_EADDRCOPY(eaddr, arg.getreq.attrval.mac.eaddr);
  return OK;
}
#endif

/****************************************************************************
 * Name: macnet_coord_saddr
 *
 * Description:
 *   Get the short address of the PAN coordinator.
 *
 * Input Parameters:
 *   radio - Reference to a radio network driver state instance.
 *   saddr - The location in which to return the short address.
 *
 * Returned Value:
 *   Zero (OK) on success; a negated errno value on failure.
 *
 ****************************************************************************/

#if defined(CONFIG_NET_STARPOINT) && !defined(CONFIG_NET_6LOWPAN_EXTENDEDADDR)
static int macnet_coord_saddr(FAR struct radio_driver_s *radio,
                              FAR uint8_t *saddr)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)radio;
  union ieee802154_macarg_u arg;
  int ret;

  arg.getreq.attr = IEEE802154_ATTR_MAC_COORD_SADDR ;
  ret = mac802154_ioctl(priv->md_mac, MAC802154IOC_MLME_GET_REQUEST,
                        (unsigned long)((uintptr_t)&arg));
  if (ret < 0)
    {
      nerr("ERROR: MAC802154IOC_MLME_GET_REQUEST failed: %d\n", ret);
      return ret;
    }

  IEEE802154_SADDRCOPY(saddr, arg.getreq.attrval.mac.saddr);
  return OK;
}
#endif

/****************************************************************************
 * Name: macnet_ifup
 *
 * Description:
 *   Creates a MAC-based IP address from the IEEE 802.15.14 short or extended
 *   address assigned to the node.
 *
 *    128  112  96   80    64   48   32   16
 *    ---- ---- ---- ----  ---- ---- ---- ----
 *    fe80 0000 0000 0000  0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
 *    fe80 0000 0000 0000  xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
 *
 * Input Parameters:
 *   dev - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static int macnet_ifup(FAR struct net_driver_s *dev)
{
  FAR struct macnet_driver_s *priv =
    (FAR struct macnet_driver_s *)dev->d_private;
  int ret;

  ret = macnet_update_nvaddr(dev);
  if (ret == OK)
    {
      uint8_t *nvaddr = dev->d_mac.radio.nv_addr;

      /* Set the IP address based on the addressing assigned to the node */

      dev->d_ipv6addr[0]  = HTONS(CONFIG_IEEE802154_NETDEV_DEFAULT_PREFIX_0);
      dev->d_ipv6addr[1]  = HTONS(CONFIG_IEEE802154_NETDEV_DEFAULT_PREFIX_1);
      dev->d_ipv6addr[2]  = HTONS(CONFIG_IEEE802154_NETDEV_DEFAULT_PREFIX_2);
      dev->d_ipv6addr[3]  = HTONS(CONFIG_IEEE802154_NETDEV_DEFAULT_PREFIX_3);

#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
      dev->d_ipv6addr[4]  = HTONS((uint16_t)nvaddr[0] << 8 | (uint16_t)nvaddr[1]);
      dev->d_ipv6addr[5]  = HTONS((uint16_t)nvaddr[2] << 8 | (uint16_t)nvaddr[3]);
      dev->d_ipv6addr[6]  = HTONS((uint16_t)nvaddr[4] << 8 | (uint16_t)nvaddr[5]);
      dev->d_ipv6addr[7]  = HTONS((uint16_t)nvaddr[6] << 8 | (uint16_t)nvaddr[7]);

      /* Invert the U/L bit */

      dev->d_ipv6addr[4] ^= HTONS(0x0200);
#else

      dev->d_ipv6addr[4]  = 0;
      dev->d_ipv6addr[5]  = HTONS(0x00ff);
      dev->d_ipv6addr[6]  = HTONS(0xfe00);
      dev->d_ipv6addr[7]  = HTONS((uint16_t)nvaddr[0] << 8 |  (uint16_t)nvaddr[1]);
#endif

      wlinfo("Bringing up: %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
             dev->d_ipv6addr[0], dev->d_ipv6addr[1], dev->d_ipv6addr[2],
             dev->d_ipv6addr[3], dev->d_ipv6addr[4], dev->d_ipv6addr[5],
             dev->d_ipv6addr[6], dev->d_ipv6addr[7]);

#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
      wlinfo("             Node: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
             dev->d_mac.radio.nv_addr[0], dev->d_mac.radio.nv_addr[1],
             dev->d_mac.radio.nv_addr[2], dev->d_mac.radio.nv_addr[3],
             dev->d_mac.radio.nv_addr[4], dev->d_mac.radio.nv_addr[5],
             dev->d_mac.radio.nv_addr[6], dev->d_mac.radio.nv_addr[7]);
#else
      wlinfo("             Node: %02x:%02x\n",
             dev->d_mac.radio.nv_addr[0], dev->d_mac.radio.nv_addr[1]);
#endif

      /* Set and activate a timer process */

      (void)wd_start(priv->md_txpoll, TXPOLL_WDDELAY, macnet_txpoll_expiry,
                     1, (wdparm_t)priv);

      ret = OK;
    }

  /* The interface is now up */

  priv->md_bifup = true;
  return ret;
}

/****************************************************************************
 * Name: macnet_ifdown
 *
 * Description:
 *   NuttX Callback: Stop the interface.
 *
 * Input Parameters:
 *   dev - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static int macnet_ifdown(FAR struct net_driver_s *dev)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)dev->d_private;
  irqstate_t flags;

  /* Disable interruption */

  flags = enter_critical_section();

  /* Cancel the TX poll timer and TX timeout timers */

  wd_cancel(priv->md_txpoll);

  /* Put the EMAC in its reset, non-operational state.  This should be
   * a known configuration that will guarantee the macnet_ifup() always
   * successfully brings the interface back up.
   */

  /* Mark the device "down" */

  priv->md_bifup = false;
  leave_critical_section(flags);
  return OK;
}

/****************************************************************************
 * Name: macnet_txavail_work
 *
 * Description:
 *   Perform an out-of-cycle poll on the worker thread.
 *
 * Input Parameters:
 *   arg - Reference to the NuttX driver state structure (cast to void*)
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *   Called on the higher priority worker thread.
 *
 ****************************************************************************/

static void macnet_txavail_work(FAR void *arg)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)arg;

  wlinfo("ifup=%u\n", priv->md_bifup);

  /* Lock the network and serialize driver operations if necessary.
   * NOTE: Serialization is only required in the case where the driver work
   * is performed on an LP worker thread and where more than one LP worker
   * thread has been configured.
   */

  net_lock();

  /* Ignore the notification if the interface is not yet up */

  if (priv->md_bifup)
    {
#ifdef CONFIG_NET_6LOWPAN
      /* Make sure the our single packet buffer is attached */

      priv->md_dev.r_dev.d_buf = priv->md_iobuffer.rb_buf;
#endif

      /* Then poll the network for new XMIT data */

      (void)devif_poll(&priv->md_dev.r_dev, macnet_txpoll_callback);
    }

  net_unlock();
}

/****************************************************************************
 * Name: macnet_txavail
 *
 * Description:
 *   Driver callback invoked when new TX data is available.  This is a
 *   stimulus perform an out-of-cycle poll and, thereby, reduce the TX
 *   latency.
 *
 * Input Parameters:
 *   dev - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *   Called in normal user mode
 *
 ****************************************************************************/

static int macnet_txavail(FAR struct net_driver_s *dev)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)dev->d_private;

  wlinfo("Available=%u\n", work_available(&priv->md_pollwork));

  /* Is our single work structure available?  It may not be if there are
   * pending interrupt actions and we will have to ignore the Tx
   * availability action.
   */

  if (work_available(&priv->md_pollwork))
    {
      /* Schedule to serialize the poll on the worker thread. */

      work_queue(WPANWORK, &priv->md_pollwork, macnet_txavail_work, priv, 0);
    }

  return OK;
}

/****************************************************************************
 * Name: macnet_addmac
 *
 * Description:
 *   NuttX Callback: Add the specified MAC address to the hardware multicast
 *   address filtering
 *
 * Input Parameters:
 *   dev  - Reference to the NuttX driver state structure
 *   mac  - The MAC address to be added
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

#ifdef CONFIG_NET_MCASTGROUP
static int macnet_addmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)dev->d_private;

  /* Add the MAC address to the hardware multicast routing table.  Not used
   * with IEEE 802.15.4 radios.
   */

  return -ENOSYS;
}
#endif

/****************************************************************************
 * Name: macnet_rmmac
 *
 * Description:
 *   NuttX Callback: Remove the specified MAC address from the hardware multicast
 *   address filtering
 *
 * Input Parameters:
 *   dev  - Reference to the NuttX driver state structure
 *   mac  - The MAC address to be removed
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

#ifdef CONFIG_NET_MCASTGROUP
static int macnet_rmmac(FAR struct net_driver_s *dev, FAR const uint8_t *mac)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)dev->d_private;

  /* Remove the MAC address from the hardware multicast routing table  Not used
   * with IEEE 802.15.4 radios.
   */

  return -ENOSYS;
}
#endif

/****************************************************************************
 * Name: macnet_ioctl
 *
 * Description:
 *   Handle network IOCTL commands directed to this device.
 *
 * Input Parameters:
 *   dev - Reference to the NuttX driver state structure
 *   cmd - The IOCTL command
 *   arg - The argument for the IOCTL command
 *
 * Returned Value:
 *   OK on success; Negated errno on failure.
 *
 * Assumptions:
 *
 ****************************************************************************/

#ifdef CONFIG_NETDEV_IOCTL
static int macnet_ioctl(FAR struct net_driver_s *dev, int cmd,
                        unsigned long arg)
{
  FAR struct macnet_driver_s *priv = (FAR struct macnet_driver_s *)dev->d_private;
  int ret = -EINVAL;

  ret = nxsem_wait(&priv->md_exclsem);
  if (ret < 0)
    {
      wlerr("ERROR: nxsem_wait failed: %d\n", ret);
      return ret;
    }

  /* Check for IOCTLs aimed at the IEEE802.15.4 MAC layer */

  if (_MAC802154IOCVALID(cmd))
    {
      FAR struct ieee802154_netmac_s *netmac =
        (FAR struct ieee802154_netmac_s *)arg;

      if (netmac != NULL)
        {
          unsigned long macarg = (unsigned int)((uintptr_t)&netmac->u);

          switch (cmd)
            {
              /* Command:     MAC802154IOC_NOTIFY_REGISTER
               * Description: Register to receive a signal whenever there is a
               *              event primitive sent from the MAC layer.
               * Argument:    A read-only pointer to an instance of struct
               *              macnet_notify_s
               * Return:      Zero (OK) on success.  Minus one will be returned on
               *              failure with the errno value set appropriately.
               */

              case MAC802154IOC_NOTIFY_REGISTER:
                {
                  /* Save the notification events */

                  priv->md_notify_event       = netmac->u.event;
                  priv->md_notify_pid         = getpid();
                  priv->md_notify_registered  = true;
                  ret = OK;
                }
                break;

              case MAC802154IOC_GET_EVENT:
                {
                  FAR struct ieee802154_primitive_s *primitive;

                  while (1)
                    {
                      /* Try popping an event off the queue */

                      primitive = (FAR struct ieee802154_primitive_s *)
                                    sq_remfirst(&priv->primitive_queue);

                      /* If there was an event to pop off, copy it into the user
                       * data and free it from the MAC layer's memory.
                       */

                      if (primitive != NULL)
                        {
                          memcpy(&netmac->u, primitive,
                                 sizeof(struct ieee802154_primitive_s));

                          /* Free the event */

                          ieee802154_primitive_free(primitive);
                          ret = OK;
                          break;
                        }

                      /* There can only be one getevent pending at a time */

                      if (priv->md_eventpending)
                        {
                          ret = -EAGAIN;
                          break;
                        }

                      priv->md_eventpending = true;
                      nxsem_post(&priv->md_exclsem);

                      /* Wait to be signaled when an event is queued */

                      ret = nxsem_wait(&priv->md_eventsem);
                      if (ret < 0)
                        {
                          DEBUGASSERT(ret == -EINTR || ret == -ECANCELED);
                          priv->md_eventpending = false;
                          return ret;
                        }

                      /* Get exclusive access again, then loop back around and try and
                       * pop an event off the queue
                       */

                      ret = nxsem_wait(&priv->md_exclsem);
                      if (ret < 0)
                        {
                          wlerr("ERROR: nxsem_wait failed: %d\n", ret);
                          return ret;
                        }
                    }
                }
                break;

              case MAC802154IOC_ENABLE_EVENTS:
                {
                  priv->md_enableevents = netmac->u.enable;
                  ret = OK;
                }
                break;

              default:
                {
                  ret = mac802154_ioctl(priv->md_mac, cmd, macarg);
                }
                break;
            }
        }
    }

  /* Okay, we have no idea what this command is.. just give to the
   * IEEE802.15.4 MAC layer without modification.
   */

  else
   {
     ret = mac802154_ioctl(priv->md_mac, cmd, arg);
   }

  nxsem_post(&priv->md_exclsem);
  return ret;
}
#endif

/****************************************************************************
 * Name: macnet_get_mhrlen
 *
 * Description:
 *   Calculate the MAC header length given the frame meta-data.
 *
 * Input Parameters:
 *   netdev    - The network device that will mediate the MAC interface
 *   meta      - Obfuscated metadata structure needed to create the radio
 *               MAC header
 *
 * Returned Value:
 *   A non-negative MAC header length is returned on success; a negated
 *   errno value is returned on any failure.
 *
 ****************************************************************************/

static int macnet_get_mhrlen(FAR struct radio_driver_s *netdev,
                             FAR const void *meta)
{
  FAR struct macnet_driver_s *priv =
    (FAR struct macnet_driver_s *)netdev;
  FAR const struct ieee802154_frame_meta_s *pktmeta =
    (FAR const struct ieee802154_frame_meta_s *)meta;

  DEBUGASSERT(priv != NULL && priv->md_mac != NULL && pktmeta != NULL);
  return mac802154_get_mhrlen(priv->md_mac, pktmeta);
}

/****************************************************************************
 * Name: macnet_req_data
 *
 * Description:
 *   Requests the transfer of a list of frames to the MAC.
 *
 * Input Parameters:
 *   netdev    - The network device that will mediate the MAC interface
 *   meta      - Obfuscated metadata structure needed to create the radio
 *               MAC header
 *   framelist - Head of a list of frames to be transferred.
 *
 * Returned Value:
 *   Zero (OK) returned on success; a negated errno value is returned on
 *   any failure.
 *
 ****************************************************************************/

static int macnet_req_data(FAR struct radio_driver_s *netdev,
                           FAR const void *meta, FAR struct iob_s *framelist)
{
  FAR struct macnet_driver_s *priv =
    (FAR struct macnet_driver_s *)netdev;
  FAR const struct ieee802154_frame_meta_s *pktmeta =
    (FAR const struct ieee802154_frame_meta_s *)meta;
  FAR struct iob_s *iob;
  int ret;

  wlinfo("Received framelist\n");

  DEBUGASSERT(priv != NULL && pktmeta != NULL && framelist != NULL);

  /* Add the incoming list of frames to the MAC's outgoing queue */

  for (iob = framelist; iob != NULL; iob = framelist)
    {
      /* Increment statistics */

      NETDEV_TXPACKETS(&priv->md_dev.r_dev);

      /* Remove the IOB from the queue */

      framelist     = iob->io_flink;
      iob->io_flink = NULL;

      /* Transfer the frame to the MAC.  mac802154_req_data will return
       * -EINTR if a signal is received during certain phases of processing.
       * In this context we just need to ignore -EINTR errors and try again.
       */

      do
        {
          ret = mac802154_req_data(priv->md_mac, pktmeta, iob);
        }
      while (ret == -EINTR);

      if (ret < 0)
        {
          wlerr("ERROR: mac802154_req_data failed: %d\n", ret);

          iob_free(iob, IOBUSER_WIRELESS_MAC802154_NETDEV);
          for (iob = framelist; iob != NULL; iob = framelist)
            {
              /* Remove the IOB from the queue and free */

              framelist = iob->io_flink;
              iob_free(iob, IOBUSER_WIRELESS_MAC802154_NETDEV);
            }

          NETDEV_TXERRORS(&priv->md_dev.r_dev);
          return ret;
        }

      NETDEV_TXDONE(&priv->md_dev.r_dev);
    }

  return OK;
}

/****************************************************************************
 * Name: macnet_properties
 *
 * Description:
 *   Different packet radios may have different properties.  If there are
 *   multiple packet radios, then those properties have to be queried at
 *   run time.  This information is provided to the 6LoWPAN network via the
 *   following structure.
 *
 * Input Parameters:
 *   netdev     - The network device to be queried
 *   properties - Location where radio properties will be returned.
 *
 * Returned Value:
 *   Zero (OK) returned on success; a negated errno value is returned on
 *   any failure.
 *
 ****************************************************************************/

static int macnet_properties(FAR struct radio_driver_s *netdev,
                             FAR struct radiodev_properties_s *properties)
{
  DEBUGASSERT(netdev != NULL && properties != NULL);
  memset(properties, 0, sizeof(struct radiodev_properties_s));

  /* General */

  properties->sp_addrlen  = MACNET_ADDRSIZE;  /* Length of an address */
  properties->sp_framelen = MACNET_FRAMELEN;  /* Fixed frame length */

  /* Multicast address (uses broadcast address)
   *
   * For meshes (only) a multicast address candetermined by the first 3 bits
   * of a short address (RFC 4944):
   *
   *   0xxxxxxx xxxxxxxx: Unicast address
   *   100xxxxx xxxxxxxx: Multicast address
   *   101xxxxx xxxxxxxx: Reserved
   *   110xxxxx xxxxxxxx: Reserved
   *   111xxxxx xxxxxxxx: Reserved
   *
   * Otherwise, Multicast is implemented with the broadcast address
   * (qualified by the destination PANID).
   */

  properties->sp_mcast.nv_addrlen = IEEE802154_SADDRSIZE;
  memset(properties->sp_mcast.nv_addr, 0xff, RADIO_MAX_ADDRLEN);

  /* Broadcast address */

  properties->sp_bcast.nv_addrlen = IEEE802154_SADDRSIZE;
  memset(properties->sp_mcast.nv_addr, 0xff, RADIO_MAX_ADDRLEN);

#ifdef CONFIG_NET_STARPOINT
  /* Star hub node address.
   *
   * If this node is a "point" in a star topology, then the hub node
   * MAC address is the address of the hub/PAN coordinator.
   */

#ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
  (void)macnet_coord_eaddr(netdev, properties->sp_hubnode.nv_addr);
  properties->sp_hubnode.nv_addrlen = IEEE802154_EADDRSIZE;
#else
  (void)macnet_coord_saddr(netdev, properties->sp_hubnode.nv_addr);
  properties->sp_hubnode.nv_addrlen = IEEE802154_SADDRSIZE;
#endif
#endif

  return OK;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: mac802154netdev_register
 *
 * Description:
 *   Register a network driver to access the IEEE 802.15.4 MAC layer from
 *   a socket using 6LoWPAN
 *
 * Input Parameters:
 *   mac - Pointer to the mac layer struct to be registered.
 *
 * Returned Value:
 *   Zero (OK) is returned on success.  Otherwise a negated errno value is
 *   returned to indicate the nature of the failure.
 *
 ****************************************************************************/

int mac802154netdev_register(MACHANDLE mac)
{
  FAR struct macnet_driver_s *priv;
  FAR struct radio_driver_s *radio;
  FAR struct net_driver_s  *dev;
  FAR struct mac802154_maccb_s *maccb;
  int ret;

  DEBUGASSERT(mac != NULL);

  /* Get the interface structure associated with this interface number. */

  priv = (FAR struct macnet_driver_s *)
    kmm_zalloc(sizeof(struct macnet_driver_s));

  if (priv == NULL)
    {
      nerr("ERROR: Failed to allocate the device structure\n");
      return -ENOMEM;
    }

  /* Initialize the driver structure */

  radio               = &priv->md_dev;
  dev                 = &radio->r_dev;
  dev->d_ifup         = macnet_ifup;       /* I/F up (new IP address) callback */
  dev->d_ifdown       = macnet_ifdown;     /* I/F down callback */
  dev->d_txavail      = macnet_txavail;    /* New TX data callback */
#ifdef CONFIG_NET_MCASTGROUP
  dev->d_addmac       = macnet_addmac;     /* Add multicast MAC address */
  dev->d_rmmac        = macnet_rmmac;      /* Remove multicast MAC address */
#endif
 #ifdef CONFIG_NETDEV_IOCTL
  dev->d_ioctl        = macnet_ioctl;      /* Handle network IOCTL commands */
#endif
  dev->d_private      = (FAR void *)priv;  /* Used to recover private state from dev */

  /* Create a watchdog for timing polling for and timing of transmissions */

  priv->md_mac        = mac;               /* Save the MAC interface instance */
  priv->md_txpoll     = wd_create();       /* Create periodic poll timer */

  /* Setup a locking semaphore for exclusive device driver access */

  nxsem_init(&priv->md_exclsem, 0, 1);

  DEBUGASSERT(priv->md_txpoll != NULL);

  /* Set the network mask. */

  macnet_netmask(dev);

  /* Initialize the Network frame-related callbacks */

  radio->r_get_mhrlen = macnet_get_mhrlen;  /* Get MAC header length */
  radio->r_req_data   = macnet_req_data;    /* Enqueue frame for transmission */
  radio->r_properties = macnet_properties;  /* Return radio properties */

  /* Initialize fields related to MAC event handling */

  priv->md_eventpending = false;
  nxsem_init(&priv->md_eventsem, 0, 0);
  nxsem_setprotocol(&priv->md_eventsem, SEM_PRIO_NONE);

  sq_init(&priv->primitive_queue);

  priv->md_enableevents = false;
  priv->md_notify_registered = false;

  /* Initialize the MAC callbacks */

  priv->md_cb.mc_priv = priv;

  maccb           = &priv->md_cb.mc_cb;
  maccb->flink    = NULL;
  maccb->prio     = CONFIG_IEEE802154_NETDEV_RECVRPRIO;
  maccb->notify   = macnet_notify;

  /* Bind the callback structure */

  ret = mac802154_bind(mac, maccb);
  if (ret < 0)
    {
      nerr("ERROR: Failed to bind the MAC callbacks: %d\n", ret);
      goto errout;
    }

  ret = macnet_update_nvaddr(&priv->md_dev.r_dev);
  if (ret < 0)
    {
      nerr("ERROR: Failed updating nvaddr: %d\n", ret);
      goto errout;
    }

#ifdef CONFIG_NET_6LOWPAN
  /* Make sure the our single packet buffer is attached. We must do this before
   * registering the device since, once the device is registered, a packet may
   * be attempted to be forwarded and require the buffer.
   */

  priv->md_dev.r_dev.d_buf = priv->md_iobuffer.rb_buf;
#endif

  /* Register the device with the OS so that socket IOCTLs can be performed */

  (void)netdev_register(&priv->md_dev.r_dev, NET_LL_IEEE802154);

  /* Put the network in the DOWN state, let the user decide when to bring it up */

  dev->d_flags = IFF_DOWN;
  return macnet_ifdown(&priv->md_dev.r_dev);

errout:
  /* Release wdog timers */

  wd_delete(priv->md_txpoll);

  /* Free memory and return the error */

  kmm_free(priv);
  return ret;
}

#endif /* CONFIG_NET && CONFIG_NET_skeleton */