This comment adds (1) basic support for AF_BLUETOOTH sockets.  The logic compiles but is still incomplete.  Support for Bluetooth is general is still dependent on CONFIG_EXPERMIMENTAL because it is not yet ready for used.

Squashed commit of the following:

    wireless/bluetooth:  Some small changes that gets to a clean compile by just eliminating some incorrect implementations (still with a lot of warnings.  The logic is still incomplete but now not so lethal.
    wireless/bluetooth:  Restructuring:  Connection interfaces should internal to wireless/bluetooth.  include/nuttx/wireless/bt_conn.h removed and merged with wireless/bluetooth/bt_conn.h.  Several fix to get closer to bt_netdev.c compiling.  Need to design some not interfaces and use some existing interfaces to send and receiv packets.
    wireless/bluetooth: Some organization with some network device compile errors fixed.  Still not even close to compiling.
    net/bluetooth:  Fix numerous compile issues; Still open design issues with regard to the interface with the Bluetooth stack.
    wireless/bluetooth:  Create bt_netdev.c with a crude copy of mac802154_netdev.c.  Does not not even compile yet.
    include/nuttx/net:  Add bluetooth.h.  Content is not yet correct.
    net/netpackets:  Add bluetooth.h.  Update net/bluetooth to use new socket address definition.
    net/bluetooth:  Some fixes for initial build.
    net/bluetooth:  Add initial support for Bluetooth sockets.  The initial cut is just the a clone of the IEEE 802.15.4 socket support with name changes.
    net/ieee802154:  Fix some typos noted when cloning to create net/bluetooth.

Squashed commit of the following:

    net/udp:  Address most of the issues with UDP write buffering.  There is a remaining issue with handling one network going down in a multi-network environment.  None of this has been test but it is certainly ready for test.  Hence, the feature is marked EXPERIMENTAL.
    net/udp:  Some baby steps toward a corrected write buffering design.
    net/udp:  Remove pesky write buffer macros.
    Eliminate trailing space at the end of lines.
    net/udp:  A little more UDP write buffering logic.  Still at least on big gaping hole in the design.
    net/udp:  Undefined CONFIG_NET_SENDTO_TIMEOUT.
    net/udp:  Crude, naive port of the TCP write buffering logic into UDP.  This commit is certainly non-functional and is simply a starting point for the implementatin of UDP write buffering.
    net/udp:  Rename udp/udp_psock_sendto.c udp/udp_psock_sendto_unbuffered.c.

Squashed commit of the following:

    net/udp:  Address most of the issues with UDP write buffering.  There is a remaining issue with handling one network going down in a multi-network environment.  None of this has been test but it is certainly ready for test.  Hence, the feature is marked EXPERIMENTAL.
    net/udp:  Some baby steps toward a corrected write buffering design.
    net/udp:  Remove pesky write buffer macros.
    Eliminate trailing space at the end of lines.
    net/udp:  A little more UDP write buffering logic.  Still at least on big gaping hole in the design.
    net/udp:  Undefined CONFIG_NET_SENDTO_TIMEOUT.
    net/udp:  Crude, naive port of the TCP write buffering logic into UDP.  This commit is certainly non-functional and is simply a starting point for the implementatin of UDP write buffering.
    net/udp:  Rename udp/udp_psock_sendto.c udp/udp_psock_sendto_unbuffered.c.

This change adds support for semi-standard IPPROTO_ICMP AF_INET datagram sockets.  This replaces the old ad hoc, nonstandard way of implementing ping with a more standard, socket interface.

Squashed commit of the following:

    net/icmp:  Finishes off icmp_recvfrom().
    net/icmp:  Add readahead support for IPPROTO_ICMP sockets.
    net/icmp:  Add poll() support for IPPROTO_ICMP sockets.
    net/icmp:  Add a connection structure for IPPROTO_ICMP sockets.
    net/icmp:  Implements sendto for the IPPROTO_ICMP socket.
    net/icmp:  Move icmp_sendto() and icmp_recvfrom() to separate files.  They are likely to be complex (when they are implemented).
    net/icmp:  Hook IPPROTO_ICMP sockets into network.  Fix some naming collisions.  Still missing basic ICMP send/receive logic.
    configs: apps/system/ping current need poll() enabled.
    configs: All defconfig files that use to enable low-level support must now enabled CONFIG_SYSTEM_PING.
    net/icmp:  Adds basic build framework to support IPPROTO_ICMP sockets.

Adds OS internal function nx_write() which is functionally equivalent to write() except that it does not set the errno variable and do not cause cancellation points.

Adds OS internal functions nx_send(), ns_recv(), and nx_recvfrom() which are functionally equivalent to send(), recv(), and recvfrom() except that they do not set the errno variable and do not cause cancellation points.

    psock_close() and net_close() are internal OS functions and should not set the errno variable.

    psock_ioctl() and netdev_ioctl() are internal OS functions and should not set the errno variable.

    net_dupsd() and net_dupsd2() are internal OS functions and should not set the errno variable.

    net/ and fs/: net_vfcntl(), file_fcntl(), file_dup(), and file_dup2() are all internal OS interfaces and should not modify the errno value.

    net/: psock_recvfrom() is an internal interface and should not set the errno nor should it be a cancellation point.

    net/: psock_accept() is not a cancellation point.

    net/: psock_getsockopt() and psock_socket*9 are an internal interfaces and should not set the errno.

    net/: psock_getsockopt() is an internal interface and should not set the errno.

    net/: psock_listen() is an internal interface and should not set the errno.

    net/: psock_connect(( is an internal interface and should not set the errno nor should it be a cancellation point.

    net/: psock_bind() is an internal interface and should not set the errno.

    net/: psock_accept() is an internal interface and should not set the errno.

include/nuttx/net/net.h:  Add missing semicolon in prototype.  Fixes error in certain combinations of configuration options.

net_timedwait() and net_lockedwait() no longer return errors via errno but returned negated errno values like other internal OS functions.

commit 7029dffd02156bcbfa84262671c2ca766a117191
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 29 12:02:13 2017 -0600

    6LoWPAN PktRadio: Add missing MetaData-related prototypes and initialization logic.  Perform a major renaming to make room in the 6LoWPAN name space for packet radios.

commit e2012f7c1df14155c0bfd45d7f1cb3f71b259f48
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 29 10:16:23 2017 -0600

    6LoWPAN PktRadio:  Some initial changes to support raw packet radios without IEEE 802.15.4 with 6LoWPAN.

commit c6dbf9178539b7da75e492ffd1d1f93c9c326299
Merge: da782d6cdf 5889ce65
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 29 07:30:08 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit da782d6cdff5980d71aaa2da5f9c28ab3438d085
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 29 07:26:48 2017 -0600

    Spirit:  Completes port of the spirit radio library to NuttX.

commit 63f3595c47dca13952d28b518c7f0a8d6ae9037a
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 17:42:51 2017 -0600

    Spirit:  Bring in a couple ore more radio interface functions.

commit 692a27da396b7683749790923d8fa085091764f1
Merge: 27c0a6ec08 38f79543
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 15:49:37 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 27c0a6ec0813187f125922c81189a70cf04d83d4
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 15:47:27 2017 -0600

    Spirit:  Bring in a couple ore more radio interface functions.

commit 96657af2831487724723a60084831619257fd953
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 14:20:14 2017 -0600

    Spirit:  Bring in more radio interface functions.

commit 640d55399b54a019be68825668fca1446abd082f
Merge: 3fcf84a9a2 47791442
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 12:01:43 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 3fcf84a9a2673e1e1466ce5b114d7b73c257e515
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 12:00:31 2017 -0600

    Spirit: Brings in the last of the PktCommon interfaces.

commit d26ebd901ba4ba84910e99b4e728b98c30fa4c0b
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 09:54:52 2017 -0600

    Spirit: Add a few more PktCommon interfaces.

commit b5cb8041d50233a4abb8fb4d1dcef5428ae2c2b2
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 09:33:31 2017 -0600

    libc/termios:  Remember block comments before empty file sections.

commit 0fcab2c1c8c74442d40bd5e8c6af50a34f8a5821
Author: Sebastien Lorquet <sebastien@lorquet.fr>
Date:   Fri Jul 28 09:31:00 2017 -0600

    tcdrain implementation based on a new term ioctl

commit 797d4adf7d41068c671f0217d369b797b269de1a
Author: Stefan Kolb <Stefan.Kolb@avat.de>
Date:   Fri Jul 28 09:19:04 2017 -0600

    We discovered a problem with the samv7 mcan driver which results, under some circumstances, in a very high CPU load.

    The problem occurs, and is easily reproducible, if the device is connected to a CAN network with a wrongly configured CAN speed (baud rate). In our tests we set the CAN speed of the device to 1000000 and the speed of the other CAN nodes to 500000. The device is restarted and sends a CANopen “bootup message” to the CAN network. This results in huge amount of errors messages on the CAN bus, probably because of the CAN feature for acknowledging error messages. The error messages can’t be read by the device because of the misconfigured CAN speed, instead the CAN chip reports lots of errors, which are reported to the application which uses the CAN driver (CONFIG_CAN_ERRORS is enabled).

    The CAN errors are reported from the CAN chip via interrupts and thus the interrupt load is very high in this scenario. To fix the problem the driver now disables each RX error interrupt after it is occurred. The RX error interrupts are turned back on if at least one CAN message is received successfully.

commit e298f48e96d9e34017dcab8e4d87032862ae9322
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 28 09:06:26 2017 -0600

    Spirit:  Bring in PktStack interfaces.

commit 4a0f00a7058312dcf6ac392689b9f69112f613ec
Merge: 855cf97130 b458934a
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 18:05:02 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 855cf9713052a851a1daeb3842db2edd6ff6f658
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 18:03:56 2017 -0600

    Spirit Network Driver:  Add some hooks that will eventually support address filtering.

commit 3b3fb24ea86cf8233b034871d5c550f47ab852e6
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 17:13:21 2017 -0600

    Spirit: Add a PktStack header file.

commit 705e8fff6a21264ab751fb34c107cb109430ac89
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 15:00:03 2017 -0600

    Spirit:  Bring in last of timer interfaces.

commit f8984b2f82e165f5bba132d6b099222d1beb1fbd
Merge: cb79778a30 f287cc25
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 11:57:01 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit cb79778a3044ae97a1cc615dfa24099144f04bd0
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 11:46:31 2017 -0600

    Spirit:  Bring in last of QI interfaces.

commit 0245b330a33aa73531b82ae261b1312be9922e0f
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 10:14:34 2017 -0600

    Spirit:  Add general interfaces.

commit 121845a8f229ec2c88e5721da5512135f6624ee5
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Thu Jul 27 09:41:23 2017 -0600

    Spirit:  Bring in last of GPIO interfaces.

commit 279bfcc92bcd0cfa48c0ed7862fa2b75fbee99b8
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 17:09:19 2017 -0600

    Spirit: Add some missing configuration options: Add register -level debug options.

commit 4be89324a5908e35afc70373c279f4d05f62b48f
Merge: 66e87f9bb3 598386ef
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 15:36:20 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 66e87f9bb3ef75fddf25400bc08475c5e6ad4c30
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 15:19:56 2017 -0600

    Spirit:  Brings in last of PktBasic logic.

commit 8b4c89d6a103003fa04363e2c2ae7b9ee390bf49
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 11:55:50 2017 -0600

    Spirit:  Bring in AES and MBUS logic.

commit d00022d39ab0ce839de29386949481e5c24feff3
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 09:22:03 2017 -0600

    Spirit:  Bring in remainder of calibration interfaces.

commit 40b4b2f902e04293f8940551a97a9a24a48988dd
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 08:44:32 2017 -0600

    Spirit:  Bring in DirectRF interfaces.

commit 7c109608e1a2989f3edbc2fd939a2d225fff382a
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Wed Jul 26 07:46:19 2017 -0600

    Spirit: Add CSMA support.

commit 0f88896595d162c4ac6138e7b1af2fc35c865b3d
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 18:57:43 2017 -0600

    Spirit:  Add some initial TX logic to network driver.

commit 4dc7058dfcdcf40980578680b7e1a4206dea4ea2
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 17:02:11 2017 -0600

    Spirit: Completes ports of spirit_management.* files

commit c904eef51d929e041b87d0c8aff6fa3c2f895341
Merge: 91e985a877 c9ff8cba
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 15:15:04 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 91e985a87729017a66d19276c4d47681064f95ea
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 15:13:54 2017 -0600

    Spirit:  Add a few more functions that will soon be needed for packet transmission.

commit b5981d29983907c2194fbc26af4b72ad532bee78
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 13:30:07 2017 -0600

    Spirit:  Finish off some initialization issues; Started some interrupt handling logic.

commit c21073e0bc2870b3d9ba40bdfdfd5151ce4f5890
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 09:35:52 2017 -0600

    Spirit:  Completes very basic radio initialization for network driver

commit 1b544334361c54f46bcf0ba313c125932e8dafc6
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Tue Jul 25 07:58:30 2017 -0600

    Spirit: Add more radio initialization logic... getting closer.

commit 45d1047db60843c57d394ec910c63e7c127671e0
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 19:15:33 2017 -0600

    Spirit: add some CSMA initialization logic

commit bcf55c71336d48947fe19bb09a799169852301c2
Merge: 89e9d426e9 2fc0fbcf
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 16:47:11 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 89e9d426e91c056e659fccf5e5c4392618f8f777
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 16:44:19 2017 -0600

    Update some comments

commit 9c5d8a5833350006ed389e898b11c8c8a20e5f4f
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 16:15:54 2017 -0600

    Spirit:  Rename drivers/wireless/spirit/src to lib.  Move Spirit network driver out of IEEE802.15.4 into drivers/wireless/spirit/drivers

commit cabc0ec9e6eb558dcb715ab17264383aa0105e7a
Merge: 87b616414a 6bd744c4
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 15:38:40 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 87b616414a79c01a71acea78f8258e05325c1996
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 15:37:27 2017 -0600

    Spirit radio driver is mutating into a standalone network driver.

commit 507798233868a661ae8adad3e3aa117075a7a146
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 13:32:08 2017 -0600

    Spirit: More radio initialization logic

commit 33af25704ce9ca83d576300d153cfe31cc6d2576
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 12:19:14 2017 -0600

    Spirit:  Beginning of radio initialization logic

commit 97b20014c016e55952a8f9d8f4ae29e2cc555b23
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Mon Jul 24 09:42:06 2017 -0600

    Spirit: More initialization logic.

commit 295d8e27824c0417fccea2344b30bb5c93ffbabe
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sun Jul 23 15:39:53 2017 -0600

    Spirit:  Add header file containing enumeration of commands.

commit 8a2d9dd8eb9cc70cbcdd1b913fc9022b9c9ec8da
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sun Jul 23 11:33:50 2017 -0600

    Spirit:  Add GPIO initialization logic

commit 8b6d80c44f92024c45a6ba63ba1af3fdafe94dc3
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sun Jul 23 10:07:25 2017 -0600

    Spirit:  Add interrupt control logic.

commit 423f846fe5c914f92a4bfea4d9d1fa33de1c77a5
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 19:06:52 2017 -0600

    Spirit: Yet a little more radio initialization logic.

commit 5895b979823e51ddde5ad52e6de66a8ad662e883
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 15:36:05 2017 -0600

    Spirit: A little more radio initialization logic.

commit 86311ab30aad386203c181c792847dd1d37f9a02
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 13:02:32 2017 -0600

    Spirit: A miniscule amount of radio initialization logic.

commit ad55e89d5ee12ea1eeea95fcd38ff3da0db4416a
Merge: 90a7666655 f4e46b0d
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 10:56:30 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 90a766665534b05da0157dbc383cb06a98c86a79
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 10:52:52 2017 -0600

    Spirit1:  A few fixes for a clean build of initial configuration (not much there yet)

commit bbbf04c223230a52a7705a2161128265cfbaa480
Merge: 623d54a7f7 2319ea53
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 09:53:57 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 623d54a7f719e9032099f88f38203efee4b80722
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 09:43:52 2017 -0600

    b-l475e-iot01a: Add a configuration for testing sprit radio.

commit d309d73d9f4665f9d870eb03531f450043d9389d
Merge: 52c3ddfae6 d88dc9b2
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 09:02:06 2017 -0600

    Merge remote-tracking branch 'origin/master' into spirit

commit 52c3ddfae6802e111c2b5cf1207baf21a61dd00b
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Sat Jul 22 08:33:04 2017 -0600

    Spirit:  Add register definition header file.

commit 8d842ab5e8f9ca653b42f9ee88dc279f06b4fa98
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 17:27:03 2017 -0600

    b-l475e-iot01a: Add initial, unverified support for the SPSRGF/Spirit1 module.

commit 73d902a1048616fb9c2dd2147cabcd8ee78e19ac
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 15:49:43 2017 -0600

    Spirit: Fixes to get skeleton IEEE 802.15.4 driver build.

commit ebc5a8387bb94f0cc3827533795f3e4a33207e67
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 15:16:29 2017 -0600

    Spirit1:  Add framework for IEEE 802.15.4 driver.  Does not yet build.

commit 52e195a7ae14ddb18bdd56258f4877381d2501ca
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 14:02:42 2017 -0600

    Spirit:  A little more SPI logic.

commit 90048d0c5b8a5af4d81a15d99535c84ed38d8ae9
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 11:19:06 2017 -0600

    Spirit: Build directories setup.  Some initial files added, mostly just to verify build.

commit 8273a381ac1f6bb081b292b5e73226185e9e634c
Author: Gregory Nutt <gnutt@nuttx.org>
Date:   Fri Jul 21 08:34:04 2017 -0600

    USB composite:  Remove references to CDC/ACM and USB MSC from composite logic.  They are no longer coupled.

Sockets:  Initial steps to adde a socket interface to the networking.  Each address family will have an interface that describes how to perform socket operations on that address family.  Currently only a couple of methods are defined in the table as a proof of concept.  More to come.  Currently there are only tables for the INET/INET6 family, the Unix LOCAL family, and the raw PACKET family.  Hopefully there will be AF_IEEE802154 and AF_BLUETOOTH comming down the pike.

include/nuttx/net and net/: Move private prototype of netdev_foreach() from the public include/nuttx/net/net.h to the private net/netdev/ndetdev.h header file where it belongs.

Networking: Add registration support for integrated ieee80211 wireless drivers.  Rename CONFIG_IEEE802154 to CONFIG_WIRELESS_IEEE8021514 following the convention of including the location of the configuration variable as a part of its name.

net/: Finish IEEE802154->6LOWPAN renaming; remove PF_IEEE804154; Move 6LoWPAN menu to inside Internet Protocol Menu

nuttx/graphics and include: Replace irqsave() with enter_critical_section(); replace irqrestore() with leave_critical_section()