Remove CONFIG_NET_MULTILINK. This increases code size by a little, but greatly reduces the complexity of the network code.

drivers/net/tun.c

@@ -1189,12 +1189,8 @@ static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
       int intf;
       FAR struct ifreq *ifr = (FAR struct ifreq *)arg;
 
-#ifdef CONFIG_NET_MULTILINK
       if (!ifr || ((ifr->ifr_flags & IFF_MASK) != IFF_TUN &&
                    (ifr->ifr_flags & IFF_MASK) != IFF_TAP))
-#else
-      if (!ifr || (ifr->ifr_flags & IFF_MASK) != IFF_TUN)
-#endif
         {
           return -EINVAL;
         }
@@ -1226,7 +1222,6 @@ static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
       priv = filep->f_priv;
       strncpy(ifr->ifr_name, priv->dev.d_ifname, IFNAMSIZ);
 
-#ifdef CONFIG_NET_MULTILINK
       if ((ifr->ifr_flags & IFF_MASK) == IFF_TAP)
         {
           /* TAP device -> handling raw Ethernet packets
@@ -1243,7 +1238,6 @@ static int tun_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
 
           priv->dev.d_llhdrlen = 0;
         }
-#endif
 
       tundev_unlock(tun);
 

drivers/wireless/spirit/include/spirit_linearfifo.h

@@ -1,5 +1,5 @@
 /******************************************************************************
- * include/nuttx/wireless/spirit/include/spirit_Linearfifo.h
+ * include/nuttx/wireless/spirit/include/spirit_linearfifo.h
  * Configuration and management of SPIRIT Fifo.
  *
  *   Copyright(c) 2015 STMicroelectronics

drivers/wireless/spirit/lib/spirit_linearfifo.c

@@ -1,5 +1,5 @@
 /******************************************************************************
- * drivers/wireless/spirit/lib/spirit_Linearfifo.c
+ * drivers/wireless/spirit/lib/spirit_linearfifo.c
  * Configuration and management of SPIRIT Fifo.
  *
  *  Copyright(c) 2015 STMicroelectronics
@@ -40,7 +40,7 @@
 
 #include <assert.h>
 
-#include "spirit_Linearfifo.h"
+#include "spirit_linearfifo.h"
 #include "spirit_spi.h"
 
 /******************************************************************************

fs/nfs/nfs_vfsops.c

@@ -1808,9 +1808,9 @@ static int nfs_bind(FAR struct inode *blkdriver, FAR const void *data,
   /* But don't let the buffer size exceed the MSS of the socket type.
    *
    * In the case where there are multiple network devices with different
-   * link layer protocols (CONFIG_NET_MULTILINK), each network device
+   * link layer protocols, each network device may support a different
-   * may support a different UDP MSS value.  Here we arbitrarily select
+   * UDP MSS value.  Here we arbitrarily select the minimum MSS for
-   * the minimum MSS for that case.
+   * that case.
    */
 
   if (buflen > MIN_IPv4_UDP_MSS)

include/nuttx/net/netconfig.h

@@ -89,10 +89,6 @@
  * can be found. For Ethernet, this should be set to 14. For SLIP, this
  * should be set to 0.
  *
- * If CONFIG_NET_MULTILINK is defined, then multiple link protocols are
- * supported concurrently.  In this case, the size of link layer header
- * varies and is obtained from the network device structure.
- *
  * There are other device-specific features that at tied to the link layer:
  *
  *   - Maximum Transfer Unit (MTU)
@@ -138,132 +134,61 @@
 #  endif
 #endif
 
-#if defined(CONFIG_NET_MULTILINK)
+/* We are supporting multiple network devices using different link layer
-   /* We are supporting multiple network devices using different link layer
  * protocols.  Get the size of the link layer header from the device
  * structure.
  */
 
-#  define NET_LL_HDRLEN(d) ((d)->d_llhdrlen)
+#define NET_LL_HDRLEN(d) ((d)->d_llhdrlen)
-#  define NET_DEV_MTU(d)   ((d)->d_mtu)
+#define NET_DEV_MTU(d)   ((d)->d_mtu)
 
-#  ifdef CONFIG_NET_ETHERNET
+#ifdef CONFIG_NET_ETHERNET
 #  define _MIN_ETH_MTU   CONFIG_NET_ETH_MTU
 #  define _MAX_ETH_MTU   CONFIG_NET_ETH_MTU
-#  else
+#else
 #  define _MIN_ETH_MTU   UINT16_MAX
 #  define _MAX_ETH_MTU   0
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_LOOPBACK
+#ifdef CONFIG_NET_LOOPBACK
 #  define _MIN_LO_MTU    MIN(_MIN_ETH_MTU,1518)
 #  define _MAX_LO_MTU    MAX(_MAX_ETH_MTU,574)
-#  else
+#else
 #  define _MIN_LO_MTU   _MIN_ETH_MTU
 #  define _MAX_LO_MTU   _MAX_ETH_MTU
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_SLIP
+#ifdef CONFIG_NET_SLIP
 #  define _MIN_SLIP_MTU  MIN(_MIN_LO_MTU,CONFIG_NET_SLIP_MTU)
 #  define _MAX_SLIP_MTU  MAX(_MAX_LO_MTU,CONFIG_NET_SLIP_MTU)
-#  else
+#else
 #  define _MIN_SLIP_MTU  _MIN_LO_MTU
 #  define _MAX_SLIP_MTU  _MAX_LO_MTU
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_TUN
+#ifdef CONFIG_NET_TUN
 #  define _MIN_TUN_MTU   MIN(_MIN_SLIP_MTU,CONFIG_NET_TUN_MTU)
 #  define _MAX_TUN_MTU   MAX(_MAX_SLIP_MTU,CONFIG_NET_TUN_MTU)
-#  else
+#else
 #  define _MIN_TUN_MTU   _MIN_SLIP_MTU
 #  define _MAX_TUN_MTU   _MAX_SLIP_MTU
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_6LOWPAN
+#ifdef CONFIG_NET_6LOWPAN
 #  define _MIN_6LOWPAN_MTU  MIN(_MIN_TUN_MTU,CONFIG_NET_6LOWPAN_MTU)
 #  define _MAX_6LOWPAN_MTU  MAX(_MAX_TUN_MTU,CONFIG_NET_6LOWPAN_MTU)
-#  else
+#else
 #  define _MIN_6LOWPAN_MTU  _MIN_TUN_MTU
 #  define _MAX_6LOWPAN_MTU  _MAX_TUN_MTU
-#  endif
+#endif
 
-#  define MIN_NET_DEV_MTU  _MIN_6LOWPAN_MTU
+#define MIN_NET_DEV_MTU  _MIN_6LOWPAN_MTU
-#  define MAX_NET_DEV_MTU  _MAX_6LOWPAN_MTU
+#define MAX_NET_DEV_MTU  _MAX_6LOWPAN_MTU
 
 /* For the loopback device, we will use the largest MTU */
 
 #  define NET_LO_MTU        MAX_NET_DEV_MTU
 
-#elif defined(CONFIG_NET_SLIP)
-   /* There is no link layer header with SLIP */
-
-#  ifndef CONFIG_NET_IPv4
-#    error SLIP requires IPv4 support
-#  endif
-
-#  define NET_LL_HDRLEN(d)  0
-#  define NET_DEV_MTU(d)    CONFIG_NET_SLIP_MTU
-#  define MIN_NET_DEV_MTU   CONFIG_NET_SLIP_MTU
-#  define MAX_NET_DEV_MTU   CONFIG_NET_SLIP_MTU
-
-#elif defined(CONFIG_NET_TUN)
-   /* There is no link layer header with TUN */
-
-#  define NET_LL_HDRLEN(d)  0
-#  define NET_DEV_MTU(d)    CONFIG_NET_TUN_MTU
-#  define MIN_NET_DEV_MTU   CONFIG_NET_TUN_MTU
-#  define MAX_NET_DEV_MTU   CONFIG_NET_TUN_MTU
-
-#elif defined(CONFIG_NET_ETHERNET)
-   /* Assume standard Ethernet link layer header */
-
-#  define NET_LL_HDRLEN(d)  14
-#  define NET_DEV_MTU(d)    CONFIG_NET_ETH_MTU
-#  define MIN_NET_DEV_MTU   CONFIG_NET_ETH_MTU
-#  define MAX_NET_DEV_MTU   CONFIG_NET_ETH_MTU
-
-#elif defined(CONFIG_NET_LOOPBACK)
-  /* Force the loopback MTU to some reasonable size.  We could do something smarter, but
-   * The case where the local loopback device is the only device is very unusal.
-   */
-
-#  define NET_LO_MTU        1518
-
-   /* Assume standard Ethernet link layer header */
-
-#  define NET_LL_HDRLEN(d)  0
-#  define NET_DEV_MTU(d)    NET_LO_MTU
-#  define MIN_NET_DEV_MTU   NET_LO_MTU
-#  define MAX_NET_DEV_MTU   NET_LO_MTU
-
-#elif defined(CONFIG_NET_6LOWPAN)
-   /* There is no link layer header with 6LoWPAN */
-
-#  ifndef CONFIG_NET_IPv6
-#    error 6LoWPAN requires IP6v support
-#  endif
-
-#  define NET_LL_HDRLEN(d)  0
-#  define NET_DEV_MTU(d)    CONFIG_NET_6LOWPAN_MTU
-#  define MIN_NET_DEV_MTU   CONFIG_NET_6LOWPAN_MTU
-#  define MAX_NET_DEV_MTU   CONFIG_NET_6LOWPAN_MTU
-
-/* For the IEEE802.15.4 MAC device, we will use the packet MTU
- * (which is probably much larger than the IEEE802.15.4 fram size)
- */
-
-#  define NET_LO_MTU        MAX_NET_DEV_MTU
-
-#else
-  /* Perhaps only Unix domain sockets or the loopback device */
-
-#  define NET_LL_HDRLEN(d)  0
-#  define NET_DEV_MTU(d)    0
-#  define MIN_NET_DEV_MTU   0
-#  define MAX_NET_DEV_MTU   0
-
-#endif /* MULTILINK, SLIP, TUN, LOOPBACK, 6LoWOPAN, or ETHERNET */
-
 /* Layer 3/4 Configuration Options ******************************************/
 
 /* IP configuration options */
@@ -324,102 +249,80 @@
 
 #ifdef CONFIG_NET_ETHERNET
 #  define ETH_UDP_MSS(h)        (CONFIG_NET_ETH_MTU - ETH_HDRLEN - UDP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_UDP_MSS(h)    ETH_UDP_MSS(h)
-#    define __MAX_UDP_MSS(h)    ETH_UDP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_6LOWPAN
 #  define IEEE802154_UDP_MSS(h) (CONFIG_NET_6LOWPAN_MTU - UDP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_UDP_MSS(h)    IEEE802154_UDP_MSS(h)
-#    define __MAX_UDP_MSS(h)    IEEE802154_UDP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_LOOPBACK
 #  define LO_UDP_MSS(h)         (NET_LO_MTU - UDP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_UDP_MSS(h)    LO_UDP_MSS(h)
-#    define __MAX_UDP_MSS(h)    LO_UDP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_SLIP
 #  define SLIP_UDP_MSS(h)       (CONFIG_NET_SLIP_MTU - UDP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_UDP_MSS(h)    SLIP_UDP_MSS(h)
-#    define __MAX_UDP_MSS(h)    SLIP_UDP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_TUN
 #  define TUN_UDP_MSS(h)        (CONFIG_NET_TUN_MTU - UDP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_UDP_MSS(h)    TUN_UDP_MSS(h)
-#    define __MAX_UDP_MSS(h)    TUN_UDP_MSS(h)
-#  endif
 #endif
 
-#ifdef CONFIG_NET_MULTILINK
+#ifdef CONFIG_NET_ETHERNET
-#  ifdef CONFIG_NET_ETHERNET
 #  define __MIN_UDP_MSS(h)         ETH_UDP_MSS(h)
 #  define __MAX_UDP_MSS(h)         ETH_UDP_MSS(h)
 #  define __ETH_MIN_UDP_MSS(h)     ETH_UDP_MSS(h)
 #  define __ETH_MAX_UDP_MSS(h)     ETH_UDP_MSS(h)
-#  else
+#else
 #  define __ETH_MIN_UDP_MSS(h)     INT_MAX
 #  define __ETH_MAX_UDP_MSS(h)     0
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_6LOWPAN
+#ifdef CONFIG_NET_6LOWPAN
 #  undef  __MIN_UDP_MSS
 #  undef  __MIN_UDP_MSS
 #  define __MIN_UDP_MSS(h)         MIN(IEEE802154_UDP_MSS(h),__ETH_MIN_UDP_MSS(h))
 #  define __MAX_UDP_MSS(h)         MAX(IEEE802154_UDP_MSS(h),__ETH_MAX_UDP_MSS(h))
 #  define __6LOWPAN_MIN_UDP_MSS(h) MIN(IEEE802154_UDP_MSS(h),__ETH_MIN_UDP_MSS(h))
 #  define __6LOWPAN_MAX_UDP_MSS(h) MAX(IEEE802154_UDP_MSS(h),__ETH_MAX_UDP_MSS(h))
-#  else
+#else
 #  define __6LOWPAN_MIN_UDP_MSS(h) __ETH_MIN_UDP_MSS(h)
 #  define __6LOWPAN_MAX_UDP_MSS(h) __ETH_MAX_UDP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_LOOPBACK
+#ifdef CONFIG_NET_LOOPBACK
 #  undef  __MIN_UDP_MSS
 #  undef  __MIN_UDP_MSS
 #  define __MIN_UDP_MSS(h)        MIN(LO_UDP_MSS(h),__6LOWPAN_MIN_UDP_MSS(h))
 #  define __MAX_UDP_MSS(h)        MAX(LO_UDP_MSS(h),__6LOWPAN_MAX_UDP_MSS(h))
 #  define __LOOP_MIN_UDP_MSS(h)   MIN(LO_UDP_MSS(h),__6LOWPAN_MIN_UDP_MSS(h))
 #  define __LOOP_MAX_UDP_MSS(h)   MAX(LO_UDP_MSS(h),__6LOWPAN_MAX_UDP_MSS(h))
-#  else
+#else
 #  define __LOOP_MIN_UDP_MSS(h) __6LOWPAN_MIN_UDP_MSS(h)
 #  define __LOOP_MAX_UDP_MSS(h) __6LOWPAN_MAX_UDP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_SLIP
+#ifdef CONFIG_NET_SLIP
 #  undef  __MIN_UDP_MSS
 #  undef  __MIN_UDP_MSS
 #  define __MIN_UDP_MSS(h)      MIN(SLIP_UDP_MSS(h),__LOOP_MIN_UDP_MSS(h))
 #  define __MAX_UDP_MSS(h)      MAX(SLIP_UDP_MSS(h),__LOOP_MAX_UDP_MSS(h))
 #  define __SLIP_MIN_UDP_MSS(h) MIN(SLIP_UDP_MSS(h),__LOOP_MIN_UDP_MSS(h))
 #  define __SLIP_MAX_UDP_MSS(h) MAX(SLIP_UDP_MSS(h),__LOOP_MAX_UDP_MSS(h))
-#  else
+#else
 #  define __SLIP_MIN_UDP_MSS(h) __LOOP_MIN_UDP_MSS(h)
 #  define __SLIP_MAX_UDP_MSS(h) __LOOP_MAX_UDP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_TUN
+#ifdef CONFIG_NET_TUN
 #  undef  __MIN_UDP_MSS
 #  undef  __MIN_UDP_MSS
 #  define __MIN_UDP_MSS(h)      MIN(TUN_UDP_MSS(h),__SLIP_MIN_UDP_MSS(h))
 #  define __MAX_UDP_MSS(h)      MAX(TUN_UDP_MSS(h),__SLIP_MAX_UDP_MSS(h))
 #  define __TUN_MIN_UDP_MSS(h)  MIN(TUN_UDP_MSS(h),__SLIP_MIN_UDP_MSS(h))
 #  define __TUN_MAX_UDP_MSS(h)  MAX(TUN_UDP_MSS(h),__SLIP_MAX_UDP_MSS(h))
-#  else
+#else
 #  define __TUN_MIN_UDP_MSS(h) __SLIP_MIN_UDP_MSS(h)
 #  define __TUN_MAX_UDP_MSS(h) __SLIP_MAX_UDP_MSS(h)
-#  endif
 #endif
 
  #ifdef CONFIG_NET_IPv4
@@ -507,9 +410,8 @@
  * than NET_DEV_MTU(dev) - NET_LL_HDRLEN(dev) - IPvN_HDRLEN - TCP_HDRLEN.
  *
  * In the case where there are multiple network devices with different
- * link layer protocols (CONFIG_NET_MULTILINK), each network device
+ * link layer protocols, each network device may support a different UDP
- * may support a different UDP MSS value.  Here we arbitrarily select
+ * MSS value.  Here we arbitrarily select the minimum MSS for that case.
- * the minimum MSS for that case.
  *
  * REVISIT: TCP_HDRLEN is not really a constant!
  */
@@ -520,103 +422,80 @@
 
 #ifdef CONFIG_NET_ETHERNET
 #  define ETH_TCP_MSS(h)        (CONFIG_NET_ETH_MTU - ETH_HDRLEN - TCP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_TCP_MSS(h)    ETH_TCP_MSS(h)
-#    define __MAX_TCP_MSS(h)    ETH_TCP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_6LOWPAN
 #  define IEEE802154_TCP_MSS(h) (CONFIG_NET_6LOWPAN_MTU - TCP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_TCP_MSS(h)    IEEE802154_TCP_MSS(h)
-#    define __MAX_TCP_MSS(h)    IEEE802154_TCP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_LOOPBACK
 #  define LO_TCP_MSS(h)         (NET_LO_MTU - TCP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_TCP_MSS(h)    LO_TCP_MSS(h)
-#    define __MAX_TCP_MSS(h)    LO_TCP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_SLIP
 #  define SLIP_TCP_MSS(h)       (CONFIG_NET_SLIP_MTU - TCP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_TCP_MSS(h)    SLIP_TCP_MSS(h)
-#    define __MAX_TCP_MSS(h)    SLIP_TCP_MSS(h)
-#  endif
 #endif
 
 #ifdef CONFIG_NET_TUN
 #  define TUN_TCP_MSS(h)        (CONFIG_NET_TUN_MTU - TCP_HDRLEN - (h))
-#  ifndef CONFIG_NET_MULTILINK
-#    define __MIN_TCP_MSS(h)    TUN_TCP_MSS(h)
-#    define __MAX_TCP_MSS(h)    TUN_TCP_MSS(h)
-#  endif
 #endif
 
-#ifdef CONFIG_NET_MULTILINK
+#ifdef CONFIG_NET_ETHERNET
-
-#  ifdef CONFIG_NET_ETHERNET
 #  define __MIN_TCP_MSS(h)         ETH_TCP_MSS(h)
 #  define __MAX_TCP_MSS(h)         ETH_TCP_MSS(h)
 #  define __ETH_MIN_TCP_MSS(h)     ETH_TCP_MSS(h)
 #  define __ETH_MAX_TCP_MSS(h)     ETH_TCP_MSS(h)
-#  else
+#else
 #  define __ETH_MIN_TCP_MSS(h)     INT_MAX
 #  define __ETH_MAX_TCP_MSS(h)     0
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_6LOWPAN
+#ifdef CONFIG_NET_6LOWPAN
 #  undef  __MIN_TCP_MSS
 #  undef  __MAX_TCP_MSS
 #  define __MIN_TCP_MSS(h)         MIN(IEEE802154_TCP_MSS(h),__ETH_MIN_TCP_MSS(h))
 #  define __MAX_TCP_MSS(h)         MAX(IEEE802154_TCP_MSS(h),__ETH_MAX_TCP_MSS(h))
 #  define __6LOWPAN_MIN_TCP_MSS(h) MIN(IEEE802154_TCP_MSS(h),__ETH_MIN_TCP_MSS(h))
 #  define __6LOWPAN_MAX_TCP_MSS(h) MAX(IEEE802154_TCP_MSS(h),__ETH_MAX_TCP_MSS(h))
-#  else
+#else
 #  define __6LOWPAN_MIN_TCP_MSS(h) __ETH_MIN_TCP_MSS(h)
 #  define __6LOWPAN_MAX_TCP_MSS(h) __ETH_MAX_TCP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_LOOPBACK
+#ifdef CONFIG_NET_LOOPBACK
 #  undef  __MIN_TCP_MSS
 #  undef  __MAX_TCP_MSS
 #  define __MIN_TCP_MSS(h)         MIN(LO_TCP_MSS(h),__6LOWPAN_MIN_TCP_MSS(h))
 #  define __MAX_TCP_MSS(h)         MAX(LO_TCP_MSS(h),__6LOWPAN_MAX_TCP_MSS(h))
 #  define __LOOP_MIN_TCP_MSS(h)    MIN(LO_TCP_MSS(h),__6LOWPAN_MIN_TCP_MSS(h))
 #  define __LOOP_MAX_TCP_MSS(h)    MAX(LO_TCP_MSS(h),__6LOWPAN_MAX_TCP_MSS(h))
-#  else
+#else
 #  define __LOOP_MIN_TCP_MSS(h)   __6LOWPAN_MIN_TCP_MSS(h)
 #  define __LOOP_MAX_TCP_MSS(h)   __6LOWPAN_MAX_TCP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_SLIP
+#ifdef CONFIG_NET_SLIP
 #  undef  __MIN_TCP_MSS
 #  undef  __MAX_TCP_MSS
 #  define __MIN_TCP_MSS(h)        MIN(SLIP_TCP_MSS(h),__LOOP_MIN_TCP_MSS(h))
 #  define __MAX_TCP_MSS(h)        MAX(SLIP_TCP_MSS(h),__LOOP_MAX_TCP_MSS(h))
 #  define __SLIP_MIN_TCP_MSS(h)   MIN(SLIP_TCP_MSS(h),__LOOP_MIN_TCP_MSS(h))
 #  define __SLIP_MAX_TCP_MSS(h)   MAX(SLIP_TCP_MSS(h),__LOOP_MAX_TCP_MSS(h))
-#  else
+#else
 #  define __SLIP_MIN_TCP_MSS(h)   __LOOP_MIN_TCP_MSS(h)
 #  define __SLIP_MAX_TCP_MSS(h)   __LOOP_MAX_TCP_MSS(h)
-#  endif
+#endif
 
-#  ifdef CONFIG_NET_TUN
+#ifdef CONFIG_NET_TUN
 #  undef  __MIN_TCP_MSS
 #  undef  __MAX_TCP_MSS
 #  define __MIN_TCP_MSS(h)        MIN(TUN_TCP_MSS(h),__SLIP_MIN_TCP_MSS(h))
 #  define __MAX_TCP_MSS(h)        MAX(TUN_TCP_MSS(h),__SLIP_MAX_TCP_MSS(h))
 #  define __TUN_MIN_TCP_MSS(h)    MIN(TUN_TCP_MSS(h),__SLIP_MIN_TCP_MSS(h))
 #  define __TUN_MAX_TCP_MSS(h)    MAX(TUN_TCP_MSS(h),__SLIP_MAX_TCP_MSS(h))
-#  else
+#else
 #  define __TUN_MIN_TCP_MSS(h)    __SLIP_MIN_TCP_MSS(h)
 #  define __TUN_MAX_TCP_MSS(h)    __SLIP_MAX_TCP_MSS(h)
-#  endif
 #endif
 
 /* If IPv4 is supported, it will have the larger MSS.
@@ -653,8 +532,6 @@
  * Should be set low (i.e., to the size of the d_buf buffer) is the
  * application is slow to process incoming data, or high (32768 bytes)
  * if the application processes data quickly.
- *
- * See the note above regarding the TCP MSS and CONFIG_NET_MULTILINK.
  */
 
 #define NET_LO_TCP_RECVWNDO LO_TCP_MSS(0)
@@ -677,40 +554,12 @@
 #  endif
 #endif
 
-#if defined(CONFIG_NET_MULTILINK)
+/* We are supporting multiple network devices using different link layer
-  /* We are supporting multiple network devices using different link layer
  * protocols.  Get the size of the receive window from the device
  * structure.
  */
 
-#  define NET_DEV_RCVWNDO(d)  ((d)->d_recvwndo)
+#define NET_DEV_RCVWNDO(d)  ((d)->d_recvwndo)
-
-#elif defined(CONFIG_NET_ETHERNET)
-   /* Only Ethernet.. use the configured Ethernet receive window size */
-
-#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_ETH_TCP_RECVWNDO
-
-#elif defined(CONFIG_NET_6LOWPAN)
-   /* Only 6LoWPAN.. use the configured 6LoWPAN receive window size */
-
-#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_6LOWPAN_TCP_RECVWNDO
-
-#elif defined(CONFIG_NET_SLIP)
-   /* Only SLIP.. use the configured SLIP receive window size */
-
-#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_SLIP_TCP_RECVWNDO
-
-#elif defined(CONFIG_NET_TUN)
-   /* Only SLIP.. use the configured SLIP receive window size */
-
-#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_TUN_TCP_RECVWNDO
-
-#else /* if defined(CONFIG_NET_LOOPBACK) */
-   /* Only loal loopback.. use the fixed loopback receive window size */
-
-#  define NET_DEV_RCVWNDO(d)  NET_LO_TCP_RECVWNDO
-
-#endif /* MULTILINK, ETHERNET, 6LoWPAN, SLIP, TUN, or LOOPBACK */
 
 /* How long a connection should stay in the TIME_WAIT state.
  *

include/nuttx/net/netdev.h

@@ -227,7 +227,6 @@ struct net_driver_s
 
   uint8_t d_flags;
 
-#ifdef CONFIG_NET_MULTILINK
   /* Multi network devices using multiple data links protocols are selected */
 
   uint8_t d_lltype;             /* See enum net_lltype_e */
@@ -236,7 +235,6 @@ struct net_driver_s
 #ifdef CONFIG_NET_TCP
   uint16_t d_recvwndo;          /* TCP receive window size */
 #endif
-#endif
 
 #if defined(CONFIG_NET_ETHERNET) || defined(CONFIG_NET_6LOWPAN)
   /* Link layer address */
@@ -674,13 +672,7 @@ uint16_t ipv6_chksum(FAR struct net_driver_s *dev);
  ****************************************************************************/
 
 #ifdef CONFIG_NET_IPv4
-#if defined(CONFIG_NET_MULTILINK)
 #  define netdev_ipv4_hdrlen(dev) (dev->d_llhdrlen)
-#elif defined(CONFIG_NET_ETHERNET)
-#  define netdev_ipv4_hdrlen(dev) ETH_HDRLEN
-#else /* if defined(CONFIG_NET_SLIP) */
-#  define netdev_ipv4_hdrlen(dev) 0
-#endif
 #endif /* CONFIG_NET_IPv4 */
 
 /****************************************************************************
@@ -695,13 +687,7 @@ uint16_t ipv6_chksum(FAR struct net_driver_s *dev);
  ****************************************************************************/
 
 #ifdef CONFIG_NET_IPv6
-#if defined(CONFIG_NET_MULTILINK)
 #  define netdev_ipv6_hdrlen(dev) dev->d_llhdrlen
-#elif defined(CONFIG_NET_ETHERNET)
-#  define netdev_ipv6_hdrlen(dev) ETH_HDRLEN
-#else /* if defined(CONFIG_NET_SLIP) */
-#  define netdev_ipv6_hdrlen(dev) 0
-#endif
 #endif /* CONFIG_NET_IPv6 */
 
 #endif /* __INCLUDE_NUTTX_NET_NETDEV_H */

net/Kconfig

@@ -110,10 +110,6 @@ endmenu # Driver buffer configuration
 
 menu "Data link support"
 
-config NET_MULTILINK
-	bool
-	default n
-
 config NET_USER_DEVFMT
 	bool "User provided devfmt"
 	default n
@@ -124,7 +120,6 @@ config NET_USER_DEVFMT
 config NET_ETHERNET
 	bool "Ethernet support"
 	default y
-	select NET_MULTILINK if NET_6LOWPAN || NET_LOOPBACK || NET_SLIP || NET_TUN
 	---help---
 		If NET_SLIP is not selected, then Ethernet will be used (there is
 		no need to define anything special in the configuration file to use
@@ -133,8 +128,6 @@ config NET_ETHERNET
 config NET_6LOWPAN
 	bool "6LoWPAN support"
 	default n
-	select NET_MULTILINK if NET_ETHERNET || NET_LOOPBACK || NET_SLIP || NET_TUN
-	select NET_MULTILINK if WIRELESS_IEEE802 && WIRELESS_PKTRADIO
 	select NETDEV_IOCTL
 	select NET_HAVE_STAR
 	depends on NET_IPv6
@@ -145,14 +138,12 @@ config NET_6LOWPAN
 config NET_LOOPBACK
 	bool "Local loopback"
 	default n
-	select NET_MULTILINK if NET_ETHERNET || NET_6LOWPAN || NET_SLIP || NET_TUN
 	---help---
 		Add support for the local network loopback device, lo.
 
 config NET_SLIP
 	bool "SLIP support"
 	default n
-	select NET_MULTILINK if NET_ETHERNET || NET_6LOWPAN || NET_LOOPBACK || NET_TUN
 	---help---
 		Enables building of the SLIP driver. SLIP requires
 		at least one IP protocol selected.
@@ -198,7 +189,6 @@ endif # NET_SLIP
 config NET_TUN
 	bool "TUN Virtual Network Device support"
 	default n
-	select NET_MULTILINK if NET_ETHERNET || NET_6LOWPAN || NET_LOOPBACK || NET_SLIP
 	select ARCH_HAVE_NETDEV_STATISTICS
 
 if NET_TUN

net/arp/arp_send.c

@@ -231,7 +231,6 @@ int arp_send(in_addr_t ipaddr)
       goto errout;
     }
 
-#ifdef CONFIG_NET_MULTILINK
   /* ARP support is only built if the Ethernet data link is supported.
    * Continue and send the ARP request only if this device uses the
    * Ethernet data link protocol.
@@ -241,7 +240,6 @@ int arp_send(in_addr_t ipaddr)
     {
       return OK;
     }
-#endif
 
   /* Check if the destination address is on the local network. */
 

net/devif/devif_poll.c

@@ -124,12 +124,8 @@ static void devif_packet_conversion(FAR struct net_driver_s *dev,
 {
   if (dev->d_len > 0)
     {
-#ifdef CONFIG_NET_MULTILINK
-      /* Handle the case where multiple link layer protocols are supported */
-
       if (dev->d_lltype == NET_LL_IEEE802154 ||
           dev->d_lltype == NET_LL_PKTRADIO)
-#endif
         {
           FAR struct ipv6_hdr_s *ipv6 = (FAR struct ipv6_hdr_s *)dev->d_buf;
 

net/devif/ipv6_input.c

@@ -410,13 +410,7 @@ int ipv6_input(FAR struct net_driver_s *dev)
          * logic will be called to create the IEEE80215.4 frames.
          */
 
-#ifdef CONFIG_NET_MULTILINK
-        /* Handle the case where multiple link layer protocols are supported */
-
         if (dev->d_len > 0 && dev->d_lltype == CONFIG_NET_6LOWPAN)
-#else
-        if (dev->d_len > 0)
-#endif
           {
             /* Let 6LoWPAN handle the TCP output */
 
@@ -460,13 +454,7 @@ int ipv6_input(FAR struct net_driver_s *dev)
          * logic will be called to create the IEEE80215.4 frames.
          */
 
-#ifdef CONFIG_NET_MULTILINK
-        /* Handle the case where multiple link layer protocols are supported */
-
         if (dev->d_len > 0 && dev->d_lltype == CONFIG_NET_6LOWPAN)
-#else
-        if (dev->d_len > 0)
-#endif
           {
             /* Let 6LoWPAN handle the ICMPv6 output */
 

net/icmpv6/icmpv6.h

@@ -93,10 +93,8 @@ struct icmpv6_notify_s
 
 struct icmpv6_rnotify_s
 {
-#ifdef CONFIG_NET_MULTILINK
   FAR struct icmpv6_notify_s *rn_flink; /* Supports singly linked list */
   char rn_ifname[IFNAMSIZ];             /* Device name */
-#endif
   sem_t rn_sem;                         /* Will wake up the waiter */
   int rn_result;                        /* The result of the wait */
 };

net/icmpv6/icmpv6_advertise.c

@@ -164,9 +164,7 @@ void icmpv6_advertise(FAR struct net_driver_s *dev,
    * and use our MAC as the new source address
    */
 
-#ifdef CONFIG_NET_MULTILINK
   if (dev->d_lltype == NET_LL_ETHERNET)
-#endif
     {
       FAR struct eth_hdr_s *eth = ETHBUF;
 

net/icmpv6/icmpv6_autoconfig.c

@@ -356,7 +356,6 @@ int icmpv6_autoconfig(FAR struct net_driver_s *dev)
   DEBUGASSERT(dev);
   ninfo("Auto-configuring %s\n", dev->d_ifname);
 
-#ifdef CONFIG_NET_MULTILINK
   /* Only Ethernet devices are supported for now */
 
   if (dev->d_lltype != NET_LL_ETHERNET)
@@ -364,7 +363,6 @@ int icmpv6_autoconfig(FAR struct net_driver_s *dev)
       nerr("ERROR: Only Ethernet is supported\n");
       return -ENOSYS;
     }
-#endif
 
   /* The interface should be in the down state */
 

net/icmpv6/icmpv6_input.c

@@ -74,27 +74,7 @@
 #define ICMPv6RADVERTISE \
   ((struct icmpv6_router_advertise_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN])
 
-#if defined(CONFIG_NET_MULTILINK)
+#define DEV_LLTYPE(d) ((d)->d_lltype)
-#  define DEV_LLTYPE(d) ((d)->d_lltype)
-#elif defined(CONFIG_NET_ETHERNET)
-#  define DEV_LLTYPE(d) NET_LL_ETHERNET
-#elif defined(CONFIG_NET_6LOWPAN)
-#  if defined(CONFIG_WIRELESS_IEEE802154)
-#    define DEV_LLTYPE(d) NET_LL_IEEE802154
-#  elif defined(CONFIG_WIRELESS_PKTRADIO)
-#    define DEV_LLTYPE(d) NET_LL_PKTRADIO
-#  endif
-#elif defined(CONFIG_NET_SLIP)
-#  define DEV_LLTYPE(d) NET_LL_SLIP
-#elif defined(CONFIG_NET_TUN)
-#  define DEV_LLTYPE(d) NET_LL_TUN
-#else /* if defined(CONFIG_NET_LOOPBACK) */
-#  define DEV_LLTYPE(d) NET_LL_LOOPBACK
-#endif
-
-/****************************************************************************
- * Public Data
- ****************************************************************************/
 
 /****************************************************************************
  * Public Functions

net/icmpv6/icmpv6_neighbor.c

@@ -229,19 +229,17 @@ int icmpv6_neighbor(const net_ipv6addr_t ipaddr)
       goto errout;
     }
 
-#ifdef CONFIG_NET_MULTILINK
    * Continue and send the Neighbor Solicitation request only if this
    * device uses the Ethernet data link protocol.
    *
    * REVISIT:  Other link layer protocols may require Neighbor Discovery
-   * as well (but not SLIP which is the only other option at the moment).
+   * as well.
    */
 
   if (dev->d_lltype != NET_LL_ETHERNET)
     {
       return OK;
     }
-#endif
 
   /* Check if the destination address is on the local network. */
 

net/icmpv6/icmpv6_radvertise.c

@@ -211,9 +211,7 @@ void icmpv6_radvertise(FAR struct net_driver_s *dev)
    * and use our MAC as the new source address
    */
 
-#ifdef CONFIG_NET_MULTILINK
   if (dev->d_lltype == NET_LL_ETHERNET)
-#endif
     {
       FAR struct eth_hdr_s *eth = ETHBUF;
 

net/icmpv6/icmpv6_rsolicit.c

@@ -155,9 +155,7 @@ void icmpv6_rsolicit(FAR struct net_driver_s *dev)
   dev->d_len    = IPv6_HDRLEN + l3size;
 
 #ifdef CONFIG_NET_ETHERNET
-#ifdef CONFIG_NET_MULTILINK
   if (dev->d_lltype == NET_LL_ETHERNET)
-#endif
     {
       /* Set the destination IPv6 all-routers multicast Ethernet
        * address

net/icmpv6/icmpv6_solicit.c

@@ -168,9 +168,7 @@ void icmpv6_solicit(FAR struct net_driver_s *dev,
   dev->d_len    = IPv6_HDRLEN + l3size;
 
 #ifdef CONFIG_NET_ETHERNET
-#ifdef CONFIG_NET_MULTILINK
   if (dev->d_lltype == NET_LL_ETHERNET)
-#endif
     {
       FAR struct eth_hdr_s *eth;
 

net/inet/inet_connect.c

@@ -277,7 +277,6 @@ static uint16_t psock_connect_interrupt(FAR struct net_driver_s *dev,
 
       psock_teardown_callbacks(pstate, pstate->tc_result);
 
-#ifdef CONFIG_NET_MULTILINK
       /* When we set up the connection structure, we did not know the size
        * of the initial MSS.  Now that the connection is associated with a
        * network device, we now know the size of link layer header and can
@@ -312,8 +311,6 @@ static uint16_t psock_connect_interrupt(FAR struct net_driver_s *dev,
                   pstate->tc_conn->dev == dev);
       pstate->tc_conn->dev = dev;
 
-#endif /* CONFIG_NET_MULTILINK */
-
       /* Wake up the waiting thread */
 
       sem_post(&pstate->tc_sem);

net/ipforward/ipfwd_forward.c

@@ -147,12 +147,10 @@ static inline bool ipfwd_addrchk(FAR struct forward_s *fwd)
 
   /* REVISIT: Could the MAC address not also be in a routing table? */
 
-#ifdef CONFIG_NET_MULTILINK
   if (fwd->f_dev->d_lltype != NET_LL_ETHERNET)
     {
       return true;
     }
-#endif
 
 #ifdef CONFIG_NET_IPv4
 #ifdef CONFIG_NET_IPv6

net/ipforward/ipfwd_poll.c

@@ -74,12 +74,8 @@ static int ipfwd_packet_proto(FAR struct net_driver_s *dev)
 
   if (dev->d_len > (IPv6_HDRLEN + llhdrlen))
     {
-#ifdef CONFIG_NET_MULTILINK
-      /* Handle the case where multiple link layer protocols are supported */
-
       if (dev->d_lltype == NET_LL_IEEE802154 ||
           dev->d_lltype == NET_LL_PKTRADIO)
-#endif
         {
           /* There should be an IPv6 packet at the beginning of the buffer */
 
@@ -112,13 +108,11 @@ static void ipfwd_packet_conversion(FAR struct net_driver_s *dev, int proto)
 {
   if (dev->d_len > 0)
     {
-#ifdef CONFIG_NET_MULTILINK
-      /* Handle the case where multiple link layer protocols are supported */
-
       if (dev->d_lltype == NET_LL_IEEE802154 ||
           dev->d_lltype == NET_LL_PKTRADIO)
-#endif
         {
+          FAR struct ipv6_hdr_s *ipv6 = (FAR struct ipv6_hdr_s *)dev->d_buf;
+
 #ifdef CONFIG_NET_TCP
           if (proto == IP_PROTO_TCP)
             {

net/ipforward/ipv6_forward.c

@@ -205,16 +205,12 @@ static int ipv6_packet_conversion(FAR struct net_driver_s *dev,
 
   if (dev->d_len > 0)
     {
-#ifdef CONFIG_NET_MULTILINK
-      /* Handle the case where multiple link layer protocols are supported */
-
       if (fwddev->d_lltype != NET_LL_IEEE802154 &&
           fwddev->d_lltype != NET_LL_PKTRADIO)
         {
           nwarn("WARNING:  Unsupported link layer... Not forwarded\n");
         }
       else
-#endif
 #ifdef CONFIG_NET_TCP
       if (ipv6->proto == IP_PROTO_TCP)
         {

net/neighbor/neighbor.h

@@ -74,9 +74,7 @@
 
 struct neighbor_addr_s
 {
-#ifdef CONFIG_NET_MULTILINK
   uint8_t                    na_lltype;
-#endif
   uint8_t                    na_llsize;
 
   union

net/neighbor/neighbor_add.c

@@ -96,12 +96,8 @@ void neighbor_add(FAR net_ipv6addr_t ipaddr, uint8_t lltype,
           break;
         }
 
-#ifdef CONFIG_NET_MULTILINK
       if (g_neighbors[i].ne_addr.na_lltype == lltype &&
           net_ipv6addr_cmp(g_neighbors[i].ne_ipaddr, ipaddr))
-#else
-      if (net_ipv6addr_cmp(g_neighbors[i].ne_ipaddr, ipaddr))
-#endif
         {
           oldest_ndx = i;
           break;
@@ -121,9 +117,7 @@ void neighbor_add(FAR net_ipv6addr_t ipaddr, uint8_t lltype,
   g_neighbors[oldest_ndx].ne_time = 0;
   net_ipv6addr_copy(g_neighbors[oldest_ndx].ne_ipaddr, ipaddr);
 
-#ifdef CONFIG_NET_MULTILINK
   g_neighbors[oldest_ndx].ne_addr.na_lltype = lltype;
-#endif
   g_neighbors[oldest_ndx].ne_addr.na_llsize = netdev_type_lladdrsize(lltype);
 
   memcpy(&g_neighbors[oldest_ndx].ne_addr.u, addr,

net/netdev/netdev.h

@@ -47,31 +47,6 @@
 
 #include <nuttx/net/ip.h>
 
-/****************************************************************************
- * Public Data
- ****************************************************************************/
-
-/* If there is only one supported link layer, then the size of the link
- * layer address is a constant.
- *
- * NOTE: Literal constants are used here to avoid bringing in all of the
- * header files where they are correctly defined.
- */
-
-#ifndef CONFIG_NET_MULTILINK
-#  if defined(CONFIG_NET_ETHERNET)
-#    define NETDEV_LLADDRSIZE    6   /* IFHWADDRLEN */
-#  elif defined(CONFIG_NET_6LOWPAN)
-#    ifdef CONFIG_NET_6LOWPAN_EXTENDEDADDR
-#      define NETDEV_LLADDRSIZE  10  /* NET_6LOWPAN_EADDRSIZE */
-#    else
-#      define NETDEV_LLADDRSIZE  2   /* NET_6LOWPAN_SADDRSIZE */
-#    endif
-#  else
-#    define NETDEV_LLADDRSIZE    0   /* No link layer address */
-#  endif
-#endif
-
 /****************************************************************************
  * Public Data
  ****************************************************************************/
@@ -458,11 +433,7 @@ int netdev_type_lladdrsize(uint8_t lltype);
  *
  ****************************************************************************/
 
-#ifdef CONFIG_NET_MULTILINK
+#define netdev_dev_lladdrsize(dev) netdev_type_lladdrsize((dev)->d_lltype)
-#  define netdev_dev_lladdrsize(dev) netdev_type_lladdrsize((dev)->d_lltype)
-#else
-#  define netdev_dev_lladdrsize(dev) NETDEV_LLADDRSIZE
-#endif
 
 #undef EXTERN
 #ifdef __cplusplus

net/netdev/netdev_ioctl.c

@@ -380,11 +380,7 @@ static int netdev_iee802154_ioctl(FAR struct socket *psock, int cmd,
       /* Find the device with this name */
 
       dev = netdev_findbyname(ifname);
-#ifdef CONFIG_NET_MULTILINK
       if (dev != NULL && dev->d_lltype == NET_LL_IEEE802154)
-#else
-      if (dev != NULL)
-#endif
         {
           /* Perform the device IOCTL */
 
@@ -447,11 +443,7 @@ static int netdev_pktradio_ioctl(FAR struct socket *psock, int cmd,
       /* Find the device with this name */
 
       dev = netdev_findbyname(ifname);
-#ifdef CONFIG_NET_MULTILINK
       if (dev != NULL && dev->d_lltype == NET_LL_PKTRADIO)
-#else
-      if (dev != NULL)
-#endif
         {
           /* Perform the device IOCTL */
 
@@ -825,11 +817,7 @@ static int netdev_ifr_ioctl(FAR struct socket *psock, int cmd,
           if (dev)
             {
 #ifdef CONFIG_NET_ETHERNET
-#ifdef CONFIG_NET_MULTILINK
               if (dev->d_lltype == NET_LL_ETHERNET)
-#else
-              if (true)
-#endif
                 {
                   req->ifr_hwaddr.sa_family = AF_INETX;
                   memcpy(req->ifr_hwaddr.sa_data,
@@ -840,12 +828,8 @@ static int netdev_ifr_ioctl(FAR struct socket *psock, int cmd,
 #endif
 
 #ifdef CONFIG_NET_6LOWPAN
-#ifdef CONFIG_NET_MULTILINK
               if (dev->d_lltype == NET_LL_IEEE802154 ||
                   dev->d_lltype == NET_LL_PKTRADIO)
-#else
-              if (true)
-#endif
                 {
                   req->ifr_hwaddr.sa_family = AF_INETX;
                   memcpy(req->ifr_hwaddr.sa_data,
@@ -868,11 +852,7 @@ static int netdev_ifr_ioctl(FAR struct socket *psock, int cmd,
           if (dev)
             {
 #ifdef CONFIG_NET_ETHERNET
-#ifdef CONFIG_NET_MULTILINK
               if (dev->d_lltype == NET_LL_ETHERNET)
-#else
-              if (true)
-#endif
                 {
                   memcpy(dev->d_mac.ether.ether_addr_octet,
                          req->ifr_hwaddr.sa_data, IFHWADDRLEN);
@@ -882,12 +862,8 @@ static int netdev_ifr_ioctl(FAR struct socket *psock, int cmd,
 #endif
 
 #ifdef CONFIG_NET_6LOWPAN
-#ifdef CONFIG_NET_MULTILINK
               if (dev->d_lltype == NET_LL_IEEE802154 ||
                   dev->d_lltype == NET_LL_PKTRADIO)
-#else
-              if (true)
-#endif
                 {
                   FAR struct sixlowpan_driver_s *radio;
                   struct sixlowpan_properties_s properties;

net/netdev/netdev_register.c

@@ -82,16 +82,6 @@
 #  define NETDEV_DEFAULT_FORMAT NETDEV_LO_FORMAT
 #endif
 
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/* Then next available device number */
-
-#ifndef CONFIG_NET_MULTILINK
-static int g_next_devnum = 0;
-#endif
-
 /****************************************************************************
  * Public Data
  ****************************************************************************/
@@ -119,7 +109,6 @@ struct net_driver_s *g_netdevices = NULL;
  *
  ****************************************************************************/
 
-#ifdef CONFIG_NET_MULTILINK
 static int find_devnum(FAR const char *devfmt)
 {
   FAR struct net_driver_s *curr;
@@ -151,7 +140,6 @@ static int find_devnum(FAR const char *devfmt)
 
   return result;
 }
-#endif
 
 /****************************************************************************
  * Public Functions
@@ -187,11 +175,8 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
 
   if (dev != NULL)
     {
-#ifdef CONFIG_NET_MULTILINK
+      /* Set the protocol used by the device and the size of the link
-      /* We are supporting multiple network devices and using different link
+       * header used by this protocol.
-       * level protocols.  Set the protocol usd by the device and the size
-       * level protocols.  Set the protocol used by the device and the size
-       * of the link header used by this protocol.
        */
 
       switch (lltype)
@@ -273,12 +258,6 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
 
       dev->d_lltype = (uint8_t)lltype;
 
-#else
-     /* Use the default device name */
-
-     devfmt = NETDEV_DEFAULT_FORMAT;
-#endif
-
       /* There are no clients of the device yet */
 
       dev->d_conncb = NULL;
@@ -290,8 +269,7 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
 
       net_lock();
 
-#ifdef CONFIG_NET_MULTILINK
+#ifdef CONFIG_NET_LOOPBACK
-#  ifdef CONFIG_NET_LOOPBACK
       /* The local loopback device is a special case:  There can be only one
        * local loopback device so it is unnumbered.
        */
@@ -301,17 +279,10 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
           devnum = 0;
         }
       else
-#  endif
+#endif
         {
           devnum = find_devnum(devfmt);
         }
-#else
-      /* There is only a single link type.  Finding the next network device
-       * number is simple.
-       */
-
-      devnum = g_next_devnum++;
-#endif
 
 #ifdef CONFIG_NET_USER_DEVFMT
       if (*dev->d_ifname)

net/procfs/netdev_statistics.c

@@ -196,9 +196,8 @@ static int netprocfs_linklayer(FAR struct netprocfs_file_s *netfile)
       status = "DOWN";
     }
 
-#if defined(CONFIG_NET_MULTILINK)
+  /* Select the output appropriate for the link type associated with
-  /* If there are multiple link types being supported, then selected the
+   * this device.
-   * output appropriate for the link type associated with this device.
    */
 
   switch (dev->d_lltype)
@@ -256,38 +255,6 @@ static int netprocfs_linklayer(FAR struct netprocfs_file_s *netfile)
 
   len += snprintf(&netfile->line[len], NET_LINELEN - len,
                   " at %s\n", status);
-
-#elif defined(CONFIG_NET_ETHERNET)
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  "%s\tLink encap:Ethernet HWaddr %s at %s\n",
-                  dev->d_ifname, ether_ntoa(&dev->d_mac.ether), status);
-
-#elif defined(CONFIG_NET_6LOWPAN)
-  len += netprocfs_6lowpan_linklayer(netfile, len);
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  " at %s\n", status);
-
-#elif defined(CONFIG_NET_LOOPBACK)
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  "%s\tLink encap:Local Loopback at %s\n",
-                  dev->d_ifname, status);
-
-#elif defined(CONFIG_NET_SLIP)
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  "%s\tLink encap:SLIP at %s\n",
-                  dev->d_ifname, status);
-
-#elif defined(CONFIG_NET_PPP)
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  "%s\tLink encap:P-t-P at %s\n",
-                  dev->d_ifname, status);
-
-#elif defined(CONFIG_NET_TUN)
-  len += snprintf(&netfile->line[len], NET_LINELEN - len,
-                  "%s\tLink encap:TUN at %s\n",
-                  dev->d_ifname, status);
-#endif
-
   return len;
 }
 

net/sixlowpan/sixlowpan_send.c

@@ -161,7 +161,6 @@ static uint16_t send_interrupt(FAR struct net_driver_s *dev,
 
   ninfo("flags: %04x: %d\n", flags);
 
-#ifdef CONFIG_NET_MULTILINK
   /* Verify that this is a compatible network driver. */
 
   if (dev->d_lltype != NET_LL_IEEE802154 &&
@@ -170,7 +169,6 @@ static uint16_t send_interrupt(FAR struct net_driver_s *dev,
       ninfo("Not a compatible network device\n");
       return flags;
     }
-#endif
 
   /* REVISIT: Verify that this is the correct IEEE802.15.4 network driver to
    * route the outgoing frame(s).  Chances are that there is only one

net/sixlowpan/sixlowpan_tcpsend.c

@@ -350,7 +350,6 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
   struct ipv6tcp_hdr_s ipv6tcp;
   int ret;
 
-#ifdef CONFIG_NET_MULTILINK
   /* Verify that this is an IEEE802.15.4 network driver. */
 
   if (dev->d_lltype != NET_LL_IEEE802154 &&
@@ -359,7 +358,6 @@ static uint16_t tcp_send_interrupt(FAR struct net_driver_s *dev,
       ninfo("Not a compatible network device\n");
       return flags;
     }
-#endif
 
   /* The TCP socket is connected and, hence, should be bound to a device.
    * Make sure that the polling device is the one that we are bound to.
@@ -803,7 +801,6 @@ ssize_t psock_6lowpan_tcp_send(FAR struct socket *psock, FAR const void *buf,
       return (ssize_t)-ENETUNREACH;
     }
 
-#ifdef CONFIG_NET_MULTILINK
   /* Some network devices support different link layer protocols.
    * Check if this device has the hooks to support 6LoWPAN.
    */
@@ -814,7 +811,6 @@ ssize_t psock_6lowpan_tcp_send(FAR struct socket *psock, FAR const void *buf,
       nwarn("WARNING: Not a compatible network device\n");
       return (ssize_t)-ENONET;
     }
-#endif
 
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
   /* Make sure that the IP address mapping is in the Neighbor Table */

net/sixlowpan/sixlowpan_udpsend.c

@@ -213,7 +213,6 @@ ssize_t psock_6lowpan_udp_sendto(FAR struct socket *psock,
       return (ssize_t)-ENETUNREACH;
     }
 
-#ifdef CONFIG_NET_MULTILINK
   /* Some network devices support different link layer protocols.
    * Check if this device has the hooks to support 6LoWPAN.
    */
@@ -224,7 +223,6 @@ ssize_t psock_6lowpan_udp_sendto(FAR struct socket *psock,
       nwarn("WARNING: Not a compatible network device\n");
       return (ssize_t)-ENONET;
     }
-#endif
 
 #ifdef CONFIG_NET_ICMPv6_NEIGHBOR
   /* Make sure that the IP address mapping is in the Neighbor Table */

net/tcp/tcp_send_buffered.c

@@ -284,12 +284,10 @@ static inline bool psock_send_addrchck(FAR struct tcp_conn_s *conn)
 {
   /* REVISIT: Could the MAC address not also be in a routing table? */
 
-#ifdef CONFIG_NET_MULTILINK
   if (conn->dev->d_lltype != NET_LL_ETHERNET)
     {
       return true;
     }
-#endif
 
 #ifdef CONFIG_NET_IPv4
 #ifdef CONFIG_NET_IPv6

net/tcp/tcp_send_unbuffered.c

@@ -235,12 +235,10 @@ static inline bool psock_send_addrchck(FAR struct tcp_conn_s *conn)
 {
   /* REVISIT: Could the MAC address not also be in a routing table? */
 
-#ifdef CONFIG_NET_MULTILINK
   if (conn->dev->d_lltype != NET_LL_ETHERNET)
     {
       return true;
     }
-#endif
 
 #ifdef CONFIG_NET_IPv4
 #ifdef CONFIG_NET_IPv6