stm32f1: unify UART0 use

boards/iot-lab_M3/include/board.h

@@ -38,7 +38,8 @@
  * @{
  */
 #define STDIO               UART_0
-#define STDIO_BAUDRATE      (115200)
+#define STDIO_BAUDRATE      (115200U)
+#define STDIO_BUFSIZE       (64U)
 /** @} */
 
 /**

boards/msbiot/include/board.h

@@ -40,6 +40,7 @@
  */
 #define STDIO               UART_0
 #define STDIO_BAUDRATE      (115200U)
+#define STDIO_BUFSIZE       (64U)
 /** @} */
 
 /**

cpu/stm32f0/Makefile.include

@@ -7,6 +7,9 @@ export USEMODULE += cortex-m0_common
 # define path to cortex-m common module, which is needed for this CPU
 export CORTEX_COMMON = $(RIOTCPU)/cortex-m0_common/
 
+# this CPU implementation makes use of the ringbuffer, so include the lib module
+export USEMODULE += lib
+
 # define the linker script to use for this CPU. The CPU_MODEL variable is defined in the
 # board's Makefile.include. This enables multiple STMF0 controllers with different memory to
 # use the same code-base.

cpu/stm32f0/syscalls.c

@@ -30,6 +30,8 @@
 
 #include "thread.h"
 #include "kernel.h"
+#include "mutex.h"
+#include "ringbuffer.h"
 #include "irq.h"
 #include "board.h"
 #include "periph/uart.h"

cpu/stm32f1/Makefile.include

@@ -4,6 +4,9 @@ export CFLAGS += -DCOREIF_NG=1
 # tell the build system that the CPU depends on the Cortex-M common files
 export USEMODULE += cortex-m3_common
 
+# this CPU implementation makes use of the ringbuffer, so include the lib module
+export USEMODULE += lib
+
 # define path to cortex-m common module, which is needed for this CPU
 export CORTEXM_COMMON = $(RIOTCPU)/cortex-m3_common/
 

cpu/stm32f1/periph/uart.c

@@ -29,11 +29,6 @@
 #include "sched.h"
 #include "thread.h"
 
-#ifdef MODULE_UART0
-#include "board_uart0.h"
-#endif
-
-
 /**
  * @brief Each UART device has to store two callbacks.
  */
@@ -296,28 +291,17 @@ static inline void irq_handler(uint8_t uartnum, USART_TypeDef *dev)
 {
     if (dev->SR & USART_SR_RXNE) {
         char data = (char)dev->DR;
-#ifdef MODULE_UART0
-        if (uart0_handler_pid) {
-            uart0_handle_incoming(data);
-
-            uart0_notify_thread();
-        }
-#else
         config[uartnum].rx_cb(config[uartnum].arg, data);
-#endif
     }
     else if (dev->SR & USART_SR_ORE) {
         /* ORE is cleared by reading SR and DR sequentially */
         dev->DR;
     }
     else if (dev->SR & USART_SR_TXE) {
-#ifdef MODULE_UART0
-        dev->SR &= ~(USART_SR_TXE);
-#else
-        config[uartnum].tx_cb(config[uartnum].arg);
-#endif
+        if (config[uartnum].tx_cb(config[uartnum].arg) == 0) {
+            dev->CR1 &= ~(USART_CR1_TXEIE);
+        }
     }
-
     if (sched_context_switch_request) {
         thread_yield();
     }

cpu/stm32f1/syscalls.c

@@ -28,28 +28,62 @@
 #include <sys/unistd.h>
 #include <stdint.h>
 
+#include "board.h"
 #include "thread.h"
 #include "kernel.h"
+#include "mutex.h"
+#include "ringbuffer.h"
 #include "irq.h"
 #include "periph/uart.h"
 
+#ifdef MODULE_UART0
+#include "board_uart0.h"
+#endif
+
 /**
  * manage the heap
  */
 extern uint32_t _end;                       /* address of last used memory cell */
 caddr_t heap_top = (caddr_t)&_end + 4;
 
+#ifndef MODULE_UART0
+/**
+ * @brief use mutex for waiting on incoming UART chars
+ */
+static mutex_t uart_rx_mutex;
+static char rx_buf_mem[STDIO_BUFSIZE];
+static ringbuffer_t rx_buf;
+#endif
+
+/**
+ * @brief Receive a new character from the UART and put it into the receive buffer
+ */
+void rx_cb(void *arg, char data)
+{
+#ifndef MODULE_UART0
+    (void)arg;
+
+    ringbuffer_add_one(&rx_buf, data);
+    mutex_unlock(&uart_rx_mutex);
+#else
+    if (uart0_handler_pid) {
+        uart0_handle_incoming(data);
+
+        uart0_notify_thread();
+    }
+#endif
+}
 
 /**
  * @brief Initialize NewLib, called by __libc_init_array() from the startup script
  */
 void _init(void)
 {
-#ifdef MODULE_UART0
-    uart_init(UART_0, 115200, NULL, NULL, NULL);
-#else
-    uart_init_blocking(UART_0, 115200);
+#ifndef MODULE_UART0
+    mutex_init(&uart_rx_mutex);
+    ringbuffer_init(&rx_buf, rx_buf_mem, STDIO_BUFSIZE);
 #endif
+    uart_init(STDIO, STDIO_BAUDRATE, rx_cb, 0, 0);
 }
 
 /**
@@ -155,11 +189,15 @@ int _open_r(struct _reent *r, const char *name, int mode)
  */
 int _read_r(struct _reent *r, int fd, void *buffer, unsigned int count)
 {
-    char c;
-    char *buff = (char*)buffer;
-    uart_read_blocking(UART_0, &c);
-    buff[0] = c;
-    return 1;
+#ifndef MODULE_UART0
+    while (rx_buf.avail == 0) {
+        mutex_lock(&uart_rx_mutex);
+    }
+    return ringbuffer_get(&rx_buf, (char*)buffer, rx_buf.avail);
+#else
+    r->_errno = ENODEV;
+    return -1;
+#endif
 }
 
 /**

cpu/stm32f4/Makefile.include

@@ -4,6 +4,9 @@ export CFLAGS += -DCOREIF_NG=1
 # export the peripheral drivers to be linked into the final binary
 export USEMODULE += periph
 
+# this CPU implementation makes use of the ringbuffer, so include the lib module
+export USEMODULE += lib
+
 # tell the build system that the CPU depends on the Cortex-M common files
 export USEMODULE += cortex-m4_common
 

cpu/stm32f4/syscalls.c

@@ -31,6 +31,8 @@
 #include "board.h"
 #include "thread.h"
 #include "kernel.h"
+#include "mutex.h"
+#include "ringbuffer.h"
 #include "irq.h"
 #include "periph/uart.h"