drivers/video:     fb driver now clears framebuffer initially.  Eliminates (or minimizes) initial garbage on the display.
    configs/open1788:  Initialization now follows the pattern of other boards.  Add initialization of fb driver.
    configs/open1788:  Add a configuration for testing the framebuffer driver.

STM32 Tickless: The attached patch removes the restriction to 16bit counts when a 32bit timer is used for the new tickless on the stm32. As it is now, the restriction is very limiting, especially if one wants high granularity and large achievable intervals and has the hardware (namely the 32bit timers) available.

drivers/xbee: Fixes a few warnings

* drivers/xbee: Fixes a few warnings

* configs/clicker2-stm32: Updates sections about i8sak usage in the README

Approved-by: Gregory Nutt <gnutt@nuttx.org>

drivers/wireless:  Adds XBee S2C (802.15.4 firmware) support. XBee driver emulates mac802154 interface

* drivers/wireless/xbee: Adds xbee_netdev. Very similar to mac802154_netdev

* configs/same70-xplained: Starts adding support for XBee radio

* drivers/wireless/ieee802154/xbee: More structuring of XBee driver

* drivers/wireless/ieee802154/xbee: More Xbee work. Starts adding support on Clicker2

* drivers/wireless/ieee802154/xbee: More XBee MAC code

* configs/clicker2-stm32: More work to add XBee radio support

* drivers/wireless/ieee802154/xbee: Most of driver is now structured. No build errors

* configs/clicker2-stm32: Adjustments to XBee click module support

* drivers/xbee: Changes md_ prefix to xd_ prefix for xbeenet_driver_s fields

* drivers/xbee: XBee network device now passes MAC events via IOCTL

* drivers/xbee: Support querying device for parameters, setting parameters, and structures association/startpan logic

* configs/clicker2-stm32: Fixes Xbee lower half ATTN poll logic

* drivers/xbee: Removes dependce on CONFIG_IEEE802154_NETDEV

* drivers/xbee: Supports MAC RESET.request primitive

* drivers/xbee: Exposes generic AT query to the rest of driver

* drivers/xbee: Sets local values when writing setting change to Xbee device

* drivers/xbee: Finish association logic

* drivers/xbee: Adds xbee_get_mhrlen( ) allocating enough space for API frame header to frame

* drivers/xbee: Finishes transmit/receive logic

* drivers/xbee: Fixes xbee_netdev to match logic in mac802154_netdev.c

* drivers/xbee: Rearranges logic to prevent a loop condition where recursion could potentially occur to the point of deadlocking the system

Approved-by: Gregory Nutt <gnutt@nuttx.org>

    Merged in merlin17/nuttx/mac802154-sock (pull request #479)

    wireless/ieee802154: Adds support for receiving MAC events via IOCTL through socket interface. Other small fixes and cleanup

    * ioctl: Cleans up MAC802154IOC values
    * wireless/ieee802154: Cleans up MAC802154IOC_NOTIFY_REGISTER logic in character driver
    * wireless/ieee802154/mac802154_netdev:  Adds support for MAC event notification via IOCTL
    * wireless/ieee802154/mac802154: Changes reset logic. No longer reset extended address.
    * wireless/ieee802154: Cleans up MAC802154IOC logic

        Moves MAC802154IOC from ieee802154_ioctl.h and renames ieee802154_ioctl.h to ieee802154_device.h since it only contains types relevant to the MAC char device now.

    * wireless/ieee802154/mac802154_device: Cleans up IOCTL logic for recent changes.
    * drivers/wireless/ieee802154/mrf24j40: Adds missing break in case statement
    * wireless/ieee802154/mac802154_netdev: Starts adding support for passing MAC events via IOCTL
    * wireless/ieee802154/mac802154: Fixes issue with receiver enable logic
    * wireless/ieee802154/mac802154: Fixes issue where extended address is cleared and not rewritten after radio reset
    * configs/clicker2-stm32/mrf24j40-mac: Enables RAMLOG and wireless driver logging
    * wireless/ieee802154/mac802154: Fixes poll logic meant to automatically choose address mode based on short address range.

Approved-by: Gregory Nutt <gnutt@nuttx.org>

Added initialization code and Kconfig entries for LIS3DSH accelerometer on STM32F4Discovery + associated changes to LIS3DSH driver

Approved-by: Gregory Nutt <gnutt@nuttx.org>

driver on STM32F4Discovery rev. C boards and attach the associated interrupt callback.

Added the argument parameter (FAR void *arg) to the interrupt handler provided by the LIS3DSH
driver to fit the definition for ISRs in xcpt_t.

Changed the check for working queue availability in lis3dsh interrupt handler to use work_available()
and not crash in case of an overrun.

stm32x i2c fixes

Approved-by: Gregory Nutt <gnutt@nuttx.org>

  Injecting data errors would cause the driver to
  continually reenter the isr with BERR an RxNE.
  This fix allows the error to be cleared and
  propagated to the waiting task.

  Injecting data errors would cause the driver to
  continually reenter the isr with BERR an RxNE.
  This fix allows the error to be cleared and
  propagated to the waiting task.

Rename CONFIG_AUDIO_DEVICES to CONFIG_DRIVERS_AUDIO to conform better to the evolving configuration naming standard.

Rename CONFIG_VIDEO_DEVICES to CONFIG_DRIVERS_VIDEO to conform better to the evolving configuration naming standard.

sim/configs/fb:  Add a configuration for non-graphical testing of the frambuffer character driver using apps/example/fb

drivers/video/fb.c and include/nuttx/video.fb.h:  Some improvements and fixes from early testing sith the sim/fb cnofiguration.

latest updates on lc823450

* arch/arm/src/lc823450: Conform to the NuttX coding style

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* arch/arm/src/lc823450: Merge the latest fix in lc823450_rtc.c

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* arch/arm/src/lc823450: Add ADC driver

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* arch/arm/src/lc823450: Add watchdog driver

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* configs/lc823450-xgevk: Enable ADC and watchdog driver

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

Approved-by: Gregory Nutt <gnutt@nuttx.org>

drivers/video/fb.c:  Add support for LCD drivers that use a simulated framebuffer and must receive explicit notification when there is an update to a region in the framebuffer.

    drivers/video/fb.c:  Framebuffer driver is code complete but as of yet untested.
    drivers/video/fb.c:  Add framebuffer character device.  This is basically only the framework for the driver; a lot of logic is still missing.

Master

* smps.c: fix error messages

* stm32f33xxx_hrtim.h: fix definition

* stm32_hrtim: fix pclk calculation

* stm32_hrtim.c: cosmetics

* smps.h: cosmetics

* add upper-half driver for high power LED driver (powerled)

* stm32f334-disco: beginning of lower half driver for high power LED (powerled)

Approved-by: Gregory Nutt <gnutt@nuttx.org>

:Remove CONFIG_NET_6LOWPAN_FRAMELEN.  In this case where multiple radios are support3d, this may not be a constant.  6LoWPAN now always queries the driver to get the maximum frame length.