From bf162b0730a5800d95099cd63b9ea4c09526c5ac Mon Sep 17 00:00:00 2001
From: Sami Korhonen <samik.korhonen@gmail.com>
Date: Sun, 9 Oct 2016 09:48:29 +0300
Subject: [PATCH] Fix DMA transmit

---
 src/main/drivers/serial_uart_hal.c       |  9 +++------
 src/main/drivers/serial_uart_stm32f7xx.c | 12 +++---------
 2 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/src/main/drivers/serial_uart_hal.c b/src/main/drivers/serial_uart_hal.c
index 22a8bdbc64..5507513379 100644
--- a/src/main/drivers/serial_uart_hal.c
+++ b/src/main/drivers/serial_uart_hal.c
@@ -85,8 +85,6 @@ static void uartReconfigure(uartPort_t *uartPort)
     if (uartPort->port.mode & MODE_TX)
         uartPort->Handle.Init.Mode |= UART_MODE_TX;
 
-    SET_BIT(uartPort->USARTx->CR3, USART_CR3_OVRDIS);
-
 
     usartConfigurePinInversion(uartPort);
 
@@ -131,7 +129,6 @@ static void uartReconfigure(uartPort_t *uartPort)
         }
         else
         {
-            //__HAL_UART_ENABLE_IT(&s->Handle, UART_IT_RXNE);
             /* Enable the UART Parity Error Interrupt */
             SET_BIT(uartPort->USARTx->CR1, USART_CR1_PEIE);
 
@@ -140,7 +137,6 @@ static void uartReconfigure(uartPort_t *uartPort)
 
             /* Enable the UART Data Register not empty Interrupt */
             SET_BIT(uartPort->USARTx->CR1, USART_CR1_RXNEIE);
-            //HAL_UART_Receive_IT(&s->Handle, (uint8_t*)s->port.rxBuffer, 1);
         }
     }
 
@@ -172,7 +168,6 @@ static void uartReconfigure(uartPort_t *uartPort)
             /* Associate the initialized DMA handle to the UART handle */
             __HAL_LINKDMA(&uartPort->Handle, hdmatx, uartPort->txDMAHandle);
 
-//            __HAL_DMA_ENABLE_IT(s->txDMAHandle, DMA_IT_TC|DMA_IT_FE|DMA_IT_TE|DMA_IT_DME);
             __HAL_DMA_SET_COUNTER(&uartPort->txDMAHandle, 0);
         } else {
             __HAL_UART_ENABLE_IT(&uartPort->Handle, UART_IT_TXE);
@@ -254,7 +249,9 @@ void uartStartTxDMA(uartPort_t *s)
 {
     uint16_t size = 0;
     uint32_t fromwhere=0;
-    //HAL_UART_DMAStop(&s->Handle);
+    HAL_UART_StateTypeDef state = HAL_UART_GetState(&s->Handle);
+    if((state & HAL_UART_STATE_BUSY_TX) == HAL_UART_STATE_BUSY_TX)
+        return;
    
     if (s->port.txBufferHead > s->port.txBufferTail) {
         size = s->port.txBufferHead - s->port.txBufferTail;
diff --git a/src/main/drivers/serial_uart_stm32f7xx.c b/src/main/drivers/serial_uart_stm32f7xx.c
index 0b054ddcd0..cb2274a6b8 100644
--- a/src/main/drivers/serial_uart_stm32f7xx.c
+++ b/src/main/drivers/serial_uart_stm32f7xx.c
@@ -309,7 +309,6 @@ void uartIrqHandler(uartPort_t *s)
             s->port.rxBuffer[s->port.rxBufferHead] = rbyte;
             s->port.rxBufferHead = (s->port.rxBufferHead + 1) % s->port.rxBufferSize;
         }
-        //__HAL_UART_CLEAR_IT(huart, UART_IT_RXNE);
         CLEAR_BIT(huart->Instance->CR1, (USART_CR1_PEIE));
 
         /* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
@@ -345,19 +344,16 @@ void uartIrqHandler(uartPort_t *s)
     /* UART in mode Transmitter ------------------------------------------------*/
     if((__HAL_UART_GET_IT(huart, UART_IT_TXE) != RESET))
     {
-      //UART_Transmit_IT(huart);
+        HAL_UART_IRQHandler(huart);
     }
 
     /* UART in mode Transmitter (transmission end) -----------------------------*/
     if((__HAL_UART_GET_IT(huart, UART_IT_TC) != RESET))
     {
-        __HAL_UART_CLEAR_IT(huart, UART_CLEAR_TCF);
+        HAL_UART_IRQHandler(huart);
+        handleUsartTxDma(s);
     }
 
-    /*if(s->txDMAStream && (s->Handle.TxXferCount == 0) && (s->Handle.TxXferSize != 0))
-    {
-        handleUsartTxDma(s);
-    }*/
 }
 
 static void handleUsartTxDma(uartPort_t *s)
@@ -367,7 +363,6 @@ static void handleUsartTxDma(uartPort_t *s)
     else
     {
         s->txDMAEmpty = true;
-        s->Handle.gState = HAL_UART_STATE_READY;
     }
 }
 
@@ -375,7 +370,6 @@ void dmaIRQHandler(dmaChannelDescriptor_t* descriptor)
 {
     uartPort_t *s = &(((uartDevice_t*)(descriptor->userParam))->port);
     HAL_DMA_IRQHandler(&s->txDMAHandle);
-    handleUsartTxDma(s);
 }
 
 uartPort_t *serialUART(UARTDevice device, uint32_t baudRate, portMode_t mode, portOptions_t options)