atsam: Add support for the SAM3X8C micro-controller

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

src/atsam/Kconfig

@@ -20,6 +20,9 @@ choice
     config MACH_SAM3X8E
         bool "SAM3x8e (Arduino Due)"
         select MACH_SAM3X
+    config MACH_SAM3X8C
+        bool "SAM3x8c (Printrboard G2)"
+        select MACH_SAM3X
     config MACH_SAM4S8C
         bool "SAM4s8c (Duet Maestro)"
         select MACH_SAM4S
@@ -42,6 +45,7 @@ config MACH_SAM4E
 config MCU
     string
     default "sam3x8e" if MACH_SAM3X8E
+    default "sam3x8c" if MACH_SAM3X8C
     default "sam4s8c" if MACH_SAM4S8C
     default "sam4e8e" if MACH_SAM4E8E
 

src/atsam/Makefile

@@ -15,6 +15,7 @@ CFLAGS-$(CONFIG_MACH_SAM3X) += -Ilib/sam3x/include
 CFLAGS-$(CONFIG_MACH_SAM4S) += -Ilib/sam4s/include
 CFLAGS-$(CONFIG_MACH_SAM4E) += -Ilib/sam4e/include
 CFLAGS-$(CONFIG_MACH_SAM3X8E) += -D__SAM3X8E__
+CFLAGS-$(CONFIG_MACH_SAM3X8C) += -D__SAM3X8C__
 CFLAGS-$(CONFIG_MACH_SAM4S8C) += -D__SAM4S8C__
 CFLAGS-$(CONFIG_MACH_SAM4E8E) += -D__SAM4E8E__
 CFLAGS += -mthumb $(CFLAGS-y) -Ilib/cmsis-core

src/atsam/gpio.c

@@ -14,6 +14,8 @@
 static Pio * const digital_regs[] = {
 #if CONFIG_MACH_SAM3X8E
     PIOA, PIOB, PIOC, PIOD
+#elif CONFIG_MACH_SAM3X8C
+    PIOA, PIOB
 #elif CONFIG_MACH_SAM4S8C
     PIOA, PIOB, PIOC
 #elif CONFIG_MACH_SAM4E8E