diff --git a/src/drivers/boards/common/board_common.h b/src/drivers/boards/common/board_common.h
index d98e218924..c35b7c5c61 100644
--- a/src/drivers/boards/common/board_common.h
+++ b/src/drivers/boards/common/board_common.h
@@ -48,6 +48,50 @@
  * Definitions
  ************************************************************************************/
 
+/* SPI bus defining tools
+ * For new boards we use a board_config.h to define all the SPI functionality
+ *  A board provides SPI bus definitions and a set of buses that should be
+ *  enumerated as well as chip selects that will be interatorable
+ *
+ * We will use these in macros place of the spi_dev_e enumeration to select a
+ * specific SPI device on given SPI1 bus.
+ *
+ * These macros will define BUS:DEV For clarity and indexing
+ *
+ * The board config then defines:
+ * 1) PX4_SPI_BUS_xxx Ids -the buses as a 1 based PX4_SPI_BUS_xxx as n+1 aping to SPI n
+ *       where n is {1-highest SPI supported by SoC}
+ * 2) PX4_SPIDEV_yyyy handles - PX4_SPIDEV_xxxxx handles using the macros below.
+ * 3) PX4_xxxx_BUS_CS_GPIO - a set of chip selects that are indexed by the handles. and of set to 0 are
+ *       ignored.
+ * 4) PX4_xxxx_BUS_FIRST_CS and PX4_xxxxx_BUS_LAST_CS as  PX4_SPIDEV_lll for the first CS and
+ *       PX4_SPIDEV_hhhh as the last CS
+ *
+ * Example:
+ *
+ * The PX4_SPI_BUS_xxx
+ * #define PX4_SPI_BUS_SENSORS  1
+ * #define PX4_SPI_BUS_MEMORY   2
+ *
+ * the PX4_SPIDEV_yyyy
+ * #define PX4_SPIDEV_ICM_20689      PX4_MK_SPI_SEL(PX4_SPI_BUS_SENSORS,0)
+ * #define PX4_SPIDEV_ICM_20602      PX4_MK_SPI_SEL(PX4_SPI_BUS_SENSORS,1)
+ * #define PX4_SPIDEV_BMI055_GYRO    PX4_MK_SPI_SEL(PX4_SPI_BUS_SENSORS,2)
+ *
+ * The PX4_xxxx_BUS_CS_GPIO
+ * #define PX4_SENSOR_BUS_CS_GPIO    {GPIO_SPI_CS_ICM20689, GPIO_SPI_CS_ICM20602, GPIO_SPI_CS_BMI055_GYR,...
+ *
+ * The PX4_xxxx_BUS_FIRST_CS and PX4_xxxxx_BUS_LAST_CS
+ * #define PX4_SENSORS_BUS_FIRST_CS  PX4_SPIDEV_ICM_20689
+*  #define PX4_SENSORS_BUS_LAST_CS   PX4_SPIDEV_BMI055_ACCEL
+ *
+ *
+ */
+
+#define PX4_MK_SPI_SEL(b,d)       ((((b) & 0xf) << 4) + ((d) & 0xf))
+#define PX4_SPI_BUS_ID(bd)        (((bd) >> 4) & 0xf)
+#define PX4_SPI_DEV_ID(bd)        ((bd) & 0xf)
+
 /************************************************************************************
  * Private Functions
  ************************************************************************************/
@@ -99,3 +143,18 @@ __EXPORT int board_get_dma_usage(uint16_t *dma_total, uint16_t *dma_used, uint16
 #else
 #define board_get_dma_usage(dma_total,dma_used, dma_peak_used) (-ENOMEM)
 #endif
+
+/************************************************************************************
+ * Name: board_rc_input
+ *
+ * Description:
+ *   All boards my optionally provide this API to invert the Serial RC input.
+ *   This is needed on SoCs that support the notion RXINV or TXINV as apposed to
+ *   and external XOR controlled by a GPIO
+ *
+ ************************************************************************************/
+#if defined(INVERT_RC_INPUT)
+#  if !defined(GPIO_SBUS_INV)
+__EXPORT void board_rc_input(bool invert_on);
+#  endif
+#endif
diff --git a/src/drivers/boards/common/board_dma_alloc.c b/src/drivers/boards/common/board_dma_alloc.c
index 9ba4f23483..c0f90fb89c 100644
--- a/src/drivers/boards/common/board_dma_alloc.c
+++ b/src/drivers/boards/common/board_dma_alloc.c
@@ -46,7 +46,7 @@
 
 #include <stdint.h>
 #include <errno.h>
-#include <nuttx/gran.h>
+#include <nuttx/mm/gran.h>
 
 #include <systemlib/perf_counter.h>