[sam] 2 bugfix to SPI library.

- begin() after end() now works.
- unconnected SPI pin is selected as CS when old (non extended) API is used.

Author: cmaglie

build/shared/revisions.txt

@@ -20,6 +20,8 @@ ARDUINO 1.5.3 BETA
 
 [libraries]
 * sam: Added CAN library (still in early stage of development) (Palliser)
+* sam: Bugfix SPI library: begin() after end() now works (stimmer)
+* sam: Bugfix SPI library: incorrent pin configuration in non-extended mode.
 
 [firmwares]
 * Arduino Due: fixed USB2Serial garbage at startup (https://github.com/arduino/Arduino/pull/1267)

hardware/arduino/sam/libraries/SPI/SPI.cpp

@@ -13,13 +13,14 @@
 SPIClass::SPIClass(Spi *_spi, uint32_t _id, void(*_initCb)(void)) :
 	spi(_spi), id(_id), initCb(_initCb)
 {
-	initCb();
+	// Empty
+}
 
+void SPIClass::begin() {
+	initCb();
 	SPI_Configure(spi, id, SPI_MR_MSTR | SPI_MR_PS | SPI_MR_MODFDIS);
 	SPI_Enable(spi);
-}
 
-void SPIClass::begin() {
 	// NPCS control is left to the user
 
 	// Default speed set to 4Mhz

hardware/arduino/sam/variants/arduino_due_x/variant.h

@@ -84,7 +84,7 @@ extern "C"{
 #define BOARD_SPI_SS1        (4u)
 #define BOARD_SPI_SS2        (52u)
 #define BOARD_SPI_SS3        PIN_SPI_SS3
-#define BOARD_SPI_DEFAULT_SS BOARD_SPI_SS2
+#define BOARD_SPI_DEFAULT_SS BOARD_SPI_SS3
 
 #define BOARD_PIN_TO_SPI_PIN(x) \
 	(x==BOARD_SPI_SS0 ? PIN_SPI_SS0 : \