Refactor serial configuratin; AVR teensy Kconfig now builds

git-svn-id: https://nuttx.svn.sourceforge.net/svnroot/nuttx/trunk@5092 7fd9a85b-ad96-42d3-883c-3090e2eb8679

8 files changed, 385 insertions, 374 deletions

diff --git a/apps/examples/nsh/Kconfig b/apps/examples/nsh/Kconfig
index 289c7e515e..309aa925eb 100644
--- a/apps/examples/nsh/Kconfig
+++ b/apps/examples/nsh/Kconfig
@@ -6,6 +6,8 @@
 config EXAMPLES_NSH
 	bool "NuttShell (NSH) example"
 	default n
+	select NSH_LIBRARY
+	select SYSTEM_READLINE
 	---help---
 		Enable the NuttShell (NSH) example
 
diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index a48619140d..66fc415138 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -3260,4 +3260,5 @@
 	* Kconfig: Serial 2STOP setting must be integer 0/1, not a boolean.
 	* lib/misc/sendfile.c and include/sys/sendfile.h:  Add a Linux style
 	  sendfile() (non-standard!)
-
+	* Kconfig: Refactor serial settings (moved from chip to drivers/serial).
+	  AVR "teensy" now builds with Kconfig (contributed by Richard Cochran).
diff --git a/nuttx/arch/arm/src/lpc43xx/Kconfig b/nuttx/arch/arm/src/lpc43xx/Kconfig
index 68d705e3ef..351b940aa1 100644
--- a/nuttx/arch/arm/src/lpc43xx/Kconfig
+++ b/nuttx/arch/arm/src/lpc43xx/Kconfig
@@ -256,6 +256,7 @@ config LPC43_TMR3
 
 config LPC43_USART0
 	bool "USART0"
+	select ARCH_HAS_USART0
 	default n
 
 config LPC43_UART1
@@ -264,10 +265,12 @@ config LPC43_UART1
 
 config LPC43_USART2
 	bool "USART2"
+	select ARCH_HAS_USART2
 	default n
 
 config LPC43_USART3
 	bool "USART3"
+	select ARCH_HAS_USART3
 	default n
 
 config LPC43_USB0
@@ -289,64 +292,9 @@ config LPC43_WWDT
 
 endmenu
 
-menu "USART0 Configuration"
-	depends on LPC43_USART0
-
-config USART0_SERIAL_CONSOLE
-	bool "USART0 serial console"
-	default y
-	---help---
-		Selects the USART0 for the console and ttys0 (default is the USART0).
-
-config USART0_RXBUFSIZE
-	int "USART0 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART0_TXBUFSIZE
-	int "USART0 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART0_BAUD
-	int "USART0 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART0_BITS
-	int "USART0 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART0_PARITY
-	int "USART0 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART0_2STOP
-	int "USART0 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
-endmenu
-
 menu "UART1 Configuration"
 	depends on LPC43_UART1
 
-config UART1_SERIAL_CONSOLE
-	bool "UART1 serial console"
-	default y if !LPC43_USART0
-	---help---
-		Selects the UART1 for the console and ttys0 (default is the UART1).
-
 config UART1_RXBUFSIZE
 	int "UART1 Rx buffer size"
 	default 256
@@ -387,104 +335,6 @@ config UART1_2STOP
 
 endmenu
 
-menu "USART2 Configuration"
-	depends on LPC43_USART2
-
-config USART2_SERIAL_CONSOLE
-	bool "USART2 serial console"
-	default y if !LPC43_USART0 && !LPC43_UART1
-	---help---
-		Selects the USART2 for the console and ttys0 (default is the USART2).
-
-config USART2_RXBUFSIZE
-	int "USART2 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART2_TXBUFSIZE
-	int "USART2 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART2_BAUD
-	int "USART2 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART2_BITS
-	int "USART2 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART2_PARITY
-	int "USART2 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART2_2STOP
-	int "USART2 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
-endmenu
-
-menu "USART3 Configuration"
-	depends on LPC43_USART3
-
-config USART3_SERIAL_CONSOLE
-	bool "USART3 serial console"
-	default y if !LPC43_USART0 && !LPC43_UART1 && !LPC43_USART2
-	---help---
-		Selects the USART3 for the console and ttys0 (default is the USART3).
-
-config USART3_RXBUFSIZE
-	int "USART3 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART3_TXBUFSIZE
-	int "USART3 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART3_BAUD
-	int "USART3 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART3_BITS
-	int "USART3 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART3_PARITY
-	int "USART3 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART3_2STOP
-	int "USART3 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
-endmenu
-
 config SERIAL_TERMIOS
 	bool "Serial driver TERMIOS supported"
 	depends on LPC43_USART0 || LPC43_UART1 || LPC43_USART2 || LPC43_USART3
diff --git a/nuttx/arch/arm/src/stm32/Kconfig b/nuttx/arch/arm/src/stm32/Kconfig
index 695fe8e94d..0aa1f76b71 100644
--- a/nuttx/arch/arm/src/stm32/Kconfig
+++ b/nuttx/arch/arm/src/stm32/Kconfig
@@ -288,14 +288,17 @@ config STM32_TIM14
 
 config STM32_USART1
 	bool "USART1"
+	select ARCH_HAS_USART1
 	default n
 
 config STM32_USART2
 	bool "USART2"
+	select ARCH_HAS_USART2
 	default n
 
 config STM32_USART3
 	bool "USART3"
+	select ARCH_HAS_USART3
 	default n
 
 config STM32_UART4
@@ -309,6 +312,7 @@ config STM32_UART5
 config STM32_USART6
 	bool "USART6"
 	default n
+	select ARCH_HAS_USART6
 	depends on STM32_STM32F20XX || STM32_STM32F40XX
 
 config STM32_USB
@@ -1420,53 +1424,6 @@ config STM32_TIM14_DAC2
 
 endchoice
 
-menu "USART1 Configuration"
-	depends on STM32_USART1
-
-config USART1_SERIAL_CONSOLE
-	bool "USART1 serial console"
-	default y
-	---help---
-		Selects the USART1 for the console and ttys0 (default is the USART1).
-
-config USART1_RXBUFSIZE
-	int "USART1 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART1_TXBUFSIZE
-	int "USART1 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART1_BAUD
-	int "USART1 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART1_BITS
-	int "USART1 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART1_PARITY
-	int "USART1 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART1_2STOP
-	int "USART1 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
 config USART1_RXDMA
 	bool "USART1 Rx DMA"
 	default n
@@ -1474,55 +1431,6 @@ config USART1_RXDMA
 	---help---
 		In high data rate usage, Rx DMA may eliminate Rx overrun errors
 
-endmenu
-
-menu "USART2 Configuration"
-	depends on STM32_USART2
-
-config USART2_SERIAL_CONSOLE
-	bool "USART2 serial console"
-	default y if !STM32_USART1
-	---help---
-		Selects the USART2 for the console and ttys0 (default is the USART2).
-
-config USART2_RXBUFSIZE
-	int "USART2 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART2_TXBUFSIZE
-	int "USART2 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART2_BAUD
-	int "USART2 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART2_BITS
-	int "USART2 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART2_PARITY
-	int "USART2 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART2_2STOP
-	int "USART2 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
 config USART2_RXDMA
 	bool "USART2 Rx DMA"
 	default n
@@ -1530,55 +1438,6 @@ config USART2_RXDMA
 	---help---
 		In high data rate usage, Rx DMA may eliminate Rx overrun errors
 
-endmenu
-
-menu "USART3 Configuration"
-	depends on STM32_USART3
-
-config USART3_SERIAL_CONSOLE
-	bool "USART3 serial console"
-	default y if !STM32_USART1 && !STM32_USART2
-	---help---
-		Selects the USART3 for the console and ttys0 (default is the USART3).
-
-config USART3_RXBUFSIZE
-	int "USART3 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART3_TXBUFSIZE
-	int "USART3 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART3_BAUD
-	int "USART3 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART3_BITS
-	int "USART3 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART3_PARITY
-	int "USART3 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART3_2STOP
-	int "USART3 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
 config USART3_RXDMA
 	bool "USART3 Rx DMA"
 	default n
@@ -1586,8 +1445,6 @@ config USART3_RXDMA
 	---help---
 		In high data rate usage, Rx DMA may eliminate Rx overrun errors
 
-endmenu
-
 menu "UART4 Configuration"
 	depends on STM32_UART4
 
@@ -1700,53 +1557,6 @@ config UART5_RXDMA
 
 endmenu
 
-menu "USART6 Configuration"
-	depends on STM32_USART6
-
-config USART6_SERIAL_CONSOLE
-	bool "USART6 serial console"
-	default y if !STM32_USART1 && !STM32_USART2 && !STM32_USART3 && !STM32_UART4 && !STM32_UART5
-	---help---
-		Selects the USART6 for the console and ttys0 (default is the USART6).
-
-config USART6_RXBUFSIZE
-	int "USART6 Rx buffer size"
-	default 256
-	---help---
-		Characters are buffered as received.  This specific the size of the receive
-		buffer.
-
-config USART6_TXBUFSIZE
-	int "USART6 Tx buffer size"
-	default 256
-	---help---
-		Characters are buffered before being sent.  This specific the size of the
-		transmit buffer
-
-config USART6_BAUD
-	int "USART6 BAUD"
-	default 11520
-	---help---
-		The configured BAUD of the UART
-
-config USART6_BITS
-	int "USART6 number of bits"
-	default 8
-	---help---
-		The number of bits.  Must be either 7 or 8.
-
-config USART6_PARITY
-	int "USART6 parity"
-	default 0
-	---help---
-		0=no parity, 1=odd parity, 2=even parity
-
-config USART6_2STOP
-	int "USART6 two stop bits"
-	default 0
-	---help---
-		0=1 stop bit, 1=Two stop bits.  Default: 1 stop bit
-
 config USART6_RXDMA
 	bool "USART6 Rx DMA"
 	default n
@@ -1754,8 +1564,6 @@ config USART6_RXDMA
 	---help---
 		In high data rate usage, Rx DMA may eliminate Rx overrun errors
 
-endmenu
-
 config SERIAL_TERMIOS
 	bool "Serial driver TERMIOS supported"
 	depends on STM32_USART1 || STM32_USART2 || STM32_USART3 || STM32_UART4 || STM32_UART5 || STM32_USART6
diff --git a/nuttx/arch/avr/Kconfig b/nuttx/arch/avr/Kconfig
index 0fe839b795..0108371425 100644
--- a/nuttx/arch/avr/Kconfig
+++ b/nuttx/arch/avr/Kconfig
@@ -116,4 +116,12 @@ source arch/avr/src/atmega/Kconfig
 source arch/avr/src/avr32/Kconfig
 source arch/avr/src/at32uc3/Kconfig
 
+config AVR_USART0
+	bool "USART0 specific serial device driver settings"
+	select ARCH_HAS_USART0
+
+config AVR_USART1
+	bool "USART1 specific serial device driver settings"
+	select ARCH_HAS_USART1
+
 endif
diff --git a/nuttx/arch/mips/src/pic32mx/Kconfig b/nuttx/arch/mips/src/pic32mx/Kconfig
index 7c2c9bb23d..908046f833 100644
--- a/nuttx/arch/mips/src/pic32mx/Kconfig
+++ b/nuttx/arch/mips/src/pic32mx/Kconfig
@@ -909,12 +909,6 @@ endmenu
 menu "UART1 Configuration"
 	depends on PIC32MX_UART1
 
-config UART1_SERIAL_CONSOLE
-	bool "UART1 serial console"
-	default y
-	---help---
-		Selects the UART1 for the console and ttys0.  Default: UART1 (if enabled).
-
 config UART1_RXBUFSIZE
 	int "UART1 Rx buffer size"
 	default 256
@@ -956,12 +950,6 @@ endmenu
 menu "UART2 Configuration"
 	depends on PIC32MX_UART2
 
-config UART2_SERIAL_CONSOLE
-	bool "UART2 serial console"
-	default y if !PIC32MX_UART1
-	---help---
-		Selects the UART2 for the console and ttys0.  Default: UART2 (if enabled).
-
 config UART2_RXBUFSIZE
 	int "UART2 Rx buffer size"
 	default 256
@@ -1003,12 +991,6 @@ endmenu
 menu "UART3 Configuration"
 	depends on PIC32MX_UART3
 
-config UART3_SERIAL_CONSOLE
-	bool "UART3 serial console"
-	default y if !PIC32MX_UART1 && !PIC32MX_UART2
-	---help---
-		Selects the UART3 for the console and ttys0.  Default: UART3 (if enabled).
-
 config UART3_RXBUFSIZE
 	int "UART3 Rx buffer size"
 	default 256
diff --git a/nuttx/drivers/serial/Kconfig b/nuttx/drivers/serial/Kconfig
index 96052fad38..df80a1ded5 100644
--- a/nuttx/drivers/serial/Kconfig
+++ b/nuttx/drivers/serial/Kconfig
@@ -282,4 +282,358 @@ config CONFIG_SERIAL_NPOLLWAITERS
 
 endif
 
+#
+# USARTn_XYZ settings
+#
+
+config ARCH_HAS_USART0
+       bool
+config ARCH_HAS_USART1
+       bool
+config ARCH_HAS_USART2
+       bool
+config ARCH_HAS_USART3
+       bool
+config ARCH_HAS_USART4
+       bool
+config ARCH_HAS_USART5
+       bool
+config ARCH_HAS_USART6
+       bool
+
+choice
+	prompt "Serial console"
+	depends on ARCH_HAS_USART0 || \
+	ARCH_HAS_USART1 || ARCH_HAS_USART2 || ARCH_HAS_USART3 || \
+	ARCH_HAS_USART4 || ARCH_HAS_USART5 || ARCH_HAS_USART6
+
+config USART0_SERIAL_CONSOLE
+	bool "USART0"
+	depends on ARCH_HAS_USART0
+
+config USART1_SERIAL_CONSOLE
+	bool "USART1"
+	depends on ARCH_HAS_USART1
+
+config USART2_SERIAL_CONSOLE
+	bool "USART2"
+	depends on ARCH_HAS_USART2
+
+config USART3_SERIAL_CONSOLE
+	bool "USART3"
+	depends on ARCH_HAS_USART3
+
+config USART4_SERIAL_CONSOLE
+	bool "USART4"
+	depends on ARCH_HAS_USART4
+
+config USART5_SERIAL_CONSOLE
+	bool "USART5"
+	depends on ARCH_HAS_USART5
+
+config USART6_SERIAL_CONSOLE
+	bool "USART6"
+	depends on ARCH_HAS_USART6
+
+endchoice
+
+menu "USART0 Configuration"
+	depends on ARCH_HAS_USART0
+
+config USART0_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART0_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART0_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART0_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART0_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART0_2STOP
+	int "use 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART1 Configuration"
+	depends on ARCH_HAS_USART1
+
+config USART1_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART1_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART1_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART1_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART1_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART1_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART2 Configuration"
+	depends on ARCH_HAS_USART2
+
+config USART2_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART2_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART2_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART2_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART2_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART2_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART3 Configuration"
+	depends on ARCH_HAS_USART3
+
+config USART3_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART3_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART3_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART3_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART3_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART3_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART4 Configuration"
+	depends on ARCH_HAS_USART4
+
+config USART4_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART4_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART4_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART4_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART4_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART4_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART5 Configuration"
+	depends on ARCH_HAS_USART5
+
+config USART5_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART5_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART5_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART5_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART5_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART5_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
+
+endmenu
+
+menu "USART6 Configuration"
+	depends on ARCH_HAS_USART6
+
+config USART6_RXBUFSIZE
+	int "receive buffer size"
+	default 256
+	help
+	  Characters are buffered as they are received. This specifies
+	  the size of the receive buffer.
+
+config USART6_TXBUFSIZE
+	int "transmit buffer size"
+	default 256
+	help
+	  Characters are buffered before being sent.  This specifies
+	  the size of the transmit buffer.
+
+config USART6_BAUD
+	int "baud rate"
+	default 11520
+	help
+	  The configured BAUD of the USART.
+
+config USART6_BITS
+	int "character size"
+	default 8
+	help
+	  The number of bits.  Must be either 7 or 8.
+
+config USART6_PARITY
+	int "parity setting"
+	default 0
+	help
+	  0=no parity, 1=odd parity, 2=even parity
+
+config USART6_2STOP
+	int "uses 2 stop bits"
+	default 0
+	help
+	  1=Two stop bits
 
+endmenu
diff --git a/nuttx/lib/misc/lib_sendfile.c b/nuttx/lib/misc/lib_sendfile.c
index b7959482e3..e4b53d8c87 100644
--- a/nuttx/lib/misc/lib_sendfile.c
+++ b/nuttx/lib/misc/lib_sendfile.c
@@ -125,7 +125,7 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
 
   if (offset)
     {
-      /* Use lseek to get the current position */
+      /* Use lseek to get the current file position */
 
       startpos = lseek(infd, 0, SEEK_CUR);
       if (startpos == (off_t)-1)
@@ -133,7 +133,7 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
           return ERROR;
         }
 
-      /* Use lseek again to set the new position */
+      /* Use lseek again to set the new file position */
 
       if (lseek(infd, *offset, SEEK_SET) == (off_t)-1)
         {
@@ -209,9 +209,11 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
           wrbuffer = iobuffer;
           do
             {
+              /* Write the buffer of data to the outfd */
+
               nbyteswritten = write(outfd, wrbuffer, nbytesread);
 
-              /* Check for a complete (or parial write).  write() should not
+              /* Check for a complete (or parial) write.  write() should not
                * return zero.
                */
 
@@ -261,11 +263,11 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
 
   free(iobuffer);
 
-  /* Get the current file position */
+  /* Return the current file position */
 
   if (offset)
     {
-      /* Use lseek to get the current position */
+      /* Use lseek to get the current file position */
 
       off_t curpos = lseek(infd, 0, SEEK_CUR);
       if (curpos == (off_t)-1)
@@ -277,7 +279,7 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
 
       *offset = curpos;
 
-      /* Use lseek again to restore the original position */
+      /* Use lseek again to restore the original file position */
 
       if (lseek(infd, startpos, SEEK_SET) == (off_t)-1)
         {
@@ -285,6 +287,10 @@ ssize_t sendfile(int outfd, int infd, off_t *offset, size_t count)
         }
     }
 
+  /* Finally return the number of bytes actually transferred (or ERROR
+   * if any failure occurred).
+   */
+
   return ntransferred;
 }