SPI bit order: Add configuration setting to indicate if an architecture-specif SPI implementation does or does not support LSB bit order.

arch/arm/Kconfig

@@ -51,6 +51,7 @@ config ARCH_CHIP_DM320
 config ARCH_CHIP_EFM32
 	bool "Energy Micro"
 	select ARCH_HAVE_CMNVECTOR
+	select ARCH_HAVE_SPI_BITORDER
 	select ARMV7M_CMNVECTOR
 	---help---
 		Energy Micro EFM32 microcontrollers (ARM Cortex-M).
@@ -206,14 +207,15 @@ config ARCH_CHIP_SAM34
 config ARCH_CHIP_SAMV7
 	bool "Atmel SAMV7"
 	select ARCH_HAVE_CMNVECTOR
-	select ARMV7M_CMNVECTOR
 	select ARCH_CORTEXM7
 	select ARCH_HAVE_MPU
-	select ARM_HAVE_MPU_UNIFIED
 	select ARCH_HAVE_RAMFUNCS
 	select ARCH_HAVE_TICKLESS
-	select ARMV7M_HAVE_STACKCHECK
 	select ARCH_HAVE_I2CRESET
+	select ARCH_HAVE_SPI_CS_CONTROL
+	select ARM_HAVE_MPU_UNIFIED
+	select ARMV7M_CMNVECTOR
+	select ARMV7M_HAVE_STACKCHECK
 	---help---
 		Atmel SAMV7 (ARM Cortex-M7) architectures
 
@@ -221,11 +223,12 @@ config ARCH_CHIP_STM32
 	bool "STMicro STM32 F1/F2/F3/F4"
 	select ARCH_HAVE_CMNVECTOR
 	select ARCH_HAVE_MPU
-	select ARM_HAVE_MPU_UNIFIED
 	select ARCH_HAVE_I2CRESET
 	select ARCH_HAVE_HEAPCHECK
 	select ARCH_HAVE_TICKLESS
 	select ARCH_HAVE_TIMEKEEPING
+	select ARCH_HAVE_SPI_BITORDER
+	select ARM_HAVE_MPU_UNIFIED
 	select ARMV7M_HAVE_STACKCHECK
 	---help---
 		STMicro STM32 architectures (ARM Cortex-M3/4).
@@ -233,12 +236,13 @@ config ARCH_CHIP_STM32
 config ARCH_CHIP_STM32F7
 	bool "STMicro STM32 F7"
 	select ARCH_HAVE_CMNVECTOR
-	select ARMV7M_CMNVECTOR
 	select ARCH_CORTEXM7
 	select ARCH_HAVE_MPU
-	select ARM_HAVE_MPU_UNIFIED
 	select ARCH_HAVE_I2CRESET
 	select ARCH_HAVE_HEAPCHECK
+	select ARCH_HAVE_SPI_BITORDER
+	select ARM_HAVE_MPU_UNIFIED
+	select ARMV7M_CMNVECTOR
 	select ARMV7M_HAVE_STACKCHECK
 	---help---
 		STMicro STM32 architectures (ARM Cortex-M7).
@@ -246,13 +250,14 @@ config ARCH_CHIP_STM32F7
 config ARCH_CHIP_STM32L4
 	bool "STMicro STM32 L4"
 	select ARCH_HAVE_CMNVECTOR
-	select ARMV7M_CMNVECTOR
 	select ARCH_CORTEXM4
 	select ARCH_HAVE_MPU
-	select ARM_HAVE_MPU_UNIFIED
 	select ARCH_HAVE_I2CRESET
 	select ARCH_HAVE_HEAPCHECK
 	select ARCH_HAVE_TICKLESS
+	select ARCH_HAVE_SPI_BITORDER
+	select ARM_HAVE_MPU_UNIFIED
+	select ARMV7M_CMNVECTOR
 	select ARMV7M_HAVE_STACKCHECK
 	---help---
 		STMicro STM32 architectures (ARM Cortex-M4).

drivers/lcd/memlcd.c

@@ -67,6 +67,10 @@
 #  error CONFIG_SPI_HWFEATURES=y and CONFIG_SPI_BITORDER=y required by this driver
 #endif
 
+#ifndef CONFIG_ARCH_HAVE_SPI_BITORDER
+#  warning This platform does not support SPI LSB-bit order
+#endif
+
 /* Cisplay resolution */
 
 #if defined CONFIG_MEMLCD_LS013B7DH01

drivers/spi/Kconfig

@@ -55,27 +55,42 @@ config SPI_HWFEATURES
 		basically the OR of any specific hardware feature and eanbles
 		the SPI hwfeatures() interface method.
 
+config ARCH_HAVE_SPI_CRCGENERATION
+	bool
+	default n
+
 config SPI_CRCGENERATION
 	bool
 	default n
 	select SPI_HWFEATURES
+	depends on ARCH_HAVE_SPI_CRCGENERATION
 	---help---
 		Selected by MCU Kconfig logic if implementation supports automatic
 		generation of SPI CRCs.  Enables the HWFEAT_CRCGENERATION option
 		as well as the hwfeartures() interface method.
 
+config ARCH_HAVE_SPI_CS_CONTROL
+	bool
+	default n
+
 config SPI_CS_CONTROL
 	bool "SPI CS Behavior Control"
 	default n
 	select SPI_HWFEATURES
+	depends on ARCH_HAVE_SPI_CS_CONTROL
 	---help---
 		Enables possibilities to define the behavior of CS.
 		Also enables the hwfeatures() interface method.
 
+config ARCH_HAVE_SPI_BITORDER
+	bool
+	default n
+
 config SPI_BITORDER
 	bool "SPI Bit Order Control"
 	default n
 	select SPI_HWFEATURES
+	depends on ARCH_HAVE_SPI_BITORDER
 	---help---
 		Enables capability to select MSB- or LSB-first hardware feature for
 		data transfers.

drivers/wireless/pn532.c

@@ -65,6 +65,10 @@
 #  error CONFIG_SPI_HWFEATURES=y and CONFIG_SPI_BITORDER=y required by this driver
 #endif
 
+#ifndef CONFIG_ARCH_HAVE_SPI_BITORDER
+#  warning This platform does not support SPI LSB-bit order
+#endif
+
 #ifdef CONFIG_WL_PN532_DEBUG
 #  define pn532err    _err
 #  define pn532info   _info