stm32g0: add usart.

include/libopencm3/stm32/g0/usart.h

@@ -0,0 +1,48 @@
+/** @defgroup usart_defines USART Defines
+ *
+ * @ingroup STM32G0xx_defines
+ *
+ * @brief <b>Defined Constants and Types for the STM32G0xx USART</b>
+ *
+ * @version 1.0.0
+ *
+ * LGPL License Terms @ref lgpl_license
+ *  */
+/*
+ * This file is part of the libopencm3 project.
+ *
+ * This library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef LIBOPENCM3_USART_H
+#define LIBOPENCM3_USART_H
+
+#include <libopencm3/stm32/common/usart_common_all.h>
+#include <libopencm3/stm32/common/usart_common_v2.h>
+
+/**@{*/
+
+/** @defgroup usart_reg_base USART register base addresses
+ * Holds all the U(S)ART peripherals supported.
+ * @{
+ */
+#define USART1				USART1_BASE
+#define USART2				USART2_BASE
+#define USART3				USART3_BASE
+#define USART4				USART4_BASE
+#define LPUART1				LPUART1_BASE
+/**@}*/
+
+/**@}*/
+#endif

include/libopencm3/stm32/usart.h

@@ -38,6 +38,8 @@
 #       include <libopencm3/stm32/l1/usart.h>
 #elif defined(STM32L4)
 #       include <libopencm3/stm32/l4/usart.h>
+#elif defined(STM32G0)
+#       include <libopencm3/stm32/g0/usart.h>
 #else
 #       error "stm32 family not defined."
 #endif

lib/stm32/g0/Makefile

@@ -40,6 +40,7 @@ OBJS += gpio_common_all.o gpio_common_f0234.o
 OBJS += pwr.o
 OBJS += rcc.o rcc_common_all.o
 OBJS += iwdg_common_all.o
+OBJS += usart_common_all.o usart_common_v2.o
 
 VPATH +=../:../../cm3:../common