src/main/drivers/serial_uart.c

   1 /*
   2  * This file is part of Cleanflight.
   3  *
   4  * Cleanflight is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * Cleanflight is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * Authors:
  20  * Dominic Clifton - Serial port abstraction, Separation of common STM32 code for cleanflight, various cleanups.
  21  * Hamasaki/Timecop - Initial baseflight code
  22 */
  23 #include <stdbool.h>
  24 #include <stdint.h>
  25
  26 #include "platform.h"
  27
  28 #include "build/build_config.h"
  29
  30 #include "common/utils.h"
  31
  32 #include "drivers/uart_inverter.h"
  33
  34 #include "serial.h"
  35 #include "serial_uart.h"
  36 #include "serial_uart_impl.h"
  37
  38 static void usartConfigurePinInversion(uartPort_t *uartPort) {
  39 #if !defined(USE_UART_INVERTER) && !defined(STM32F7)
  40     UNUSED(uartPort);
  41 #else
  42     bool inverted = uartPort->port.options & SERIAL_INVERTED;
  43
  44 #ifdef USE_UART_INVERTER
  45     uartInverterLine_e invertedLines = UART_INVERTER_LINE_NONE;
  46     if (uartPort->port.mode & MODE_RX) {
  47         invertedLines |= UART_INVERTER_LINE_RX;
  48     }
  49     if (uartPort->port.mode & MODE_TX) {
  50         invertedLines |= UART_INVERTER_LINE_TX;
  51     }
  52     uartInverterSet(uartPort->USARTx, invertedLines, inverted);
  53 #endif
  54
  55 #endif
  56 }
  57
  58 static void uartReconfigure(uartPort_t *uartPort)
  59 {
  60     USART_InitTypeDef USART_InitStructure;
  61     USART_Cmd(uartPort->USARTx, DISABLE);
  62
  63     USART_InitStructure.USART_BaudRate = uartPort->port.baudRate;
  64
  65     // according to the stm32 documentation wordlen has to be 9 for parity bits
  66     // this does not seem to matter for rx but will give bad data on tx!
  67     if (uartPort->port.options & SERIAL_PARITY_EVEN) {
  68         USART_InitStructure.USART_WordLength = USART_WordLength_9b;
  69     } else {
  70         USART_InitStructure.USART_WordLength = USART_WordLength_8b;
  71     }
  72
  73     USART_InitStructure.USART_StopBits = (uartPort->port.options & SERIAL_STOPBITS_2) ? USART_StopBits_2 : USART_StopBits_1;
  74     USART_InitStructure.USART_Parity   = (uartPort->port.options & SERIAL_PARITY_EVEN) ? USART_Parity_Even : USART_Parity_No;
  75
  76     USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  77     USART_InitStructure.USART_Mode = 0;
  78     if (uartPort->port.mode & MODE_RX)
  79         USART_InitStructure.USART_Mode |= USART_Mode_Rx;
  80     if (uartPort->port.mode & MODE_TX)
  81         USART_InitStructure.USART_Mode |= USART_Mode_Tx;
  82
  83     USART_Init(uartPort->USARTx, &USART_InitStructure);
  84
  85     usartConfigurePinInversion(uartPort);
  86
  87     if (uartPort->port.options & SERIAL_BIDIR)
  88         USART_HalfDuplexCmd(uartPort->USARTx, ENABLE);
  89     else
  90         USART_HalfDuplexCmd(uartPort->USARTx, DISABLE);
  91
  92     USART_Cmd(uartPort->USARTx, ENABLE);
  93 }
  94
  95 serialPort_t *uartOpen(USART_TypeDef *USARTx, serialReceiveCallbackPtr rxCallback, void *rxCallbackData, uint32_t baudRate, portMode_t mode, portOptions_t options)
  96 {
  97     uartPort_t *s = NULL;
  98
  99     if (false) {
 100 #ifdef USE_UART1
 101     } else if (USARTx == USART1) {
 102         s = serialUART1(baudRate, mode, options);
 103
 104 #endif
 105 #ifdef USE_UART2
 106     } else if (USARTx == USART2) {
 107         s = serialUART2(baudRate, mode, options);
 108 #endif
 109 #ifdef USE_UART3
 110     } else if (USARTx == USART3) {
 111         s = serialUART3(baudRate, mode, options);
 112 #endif
 113 #ifdef USE_UART4
 114     } else if (USARTx == UART4) {
 115         s = serialUART4(baudRate, mode, options);
 116 #endif
 117 #ifdef USE_UART5
 118     } else if (USARTx == UART5) {
 119         s = serialUART5(baudRate, mode, options);
 120 #endif
 121 #ifdef USE_UART6
 122     } else if (USARTx == USART6) {
 123         s = serialUART6(baudRate, mode, options);
 124 #endif
 125 #ifdef USE_UART7
 126     } else if (USARTx == UART7) {
 127         s = serialUART7(baudRate, mode, options);
 128 #endif
 129 #ifdef USE_UART8
 130     } else if (USARTx == UART8) {
 131         s = serialUART8(baudRate, mode, options);
 132 #endif
 133
 134     } else {
 135         return (serialPort_t *)s;
 136     }
 137
 138     // common serial initialisation code should move to serialPort::init()
 139     s->port.rxBufferHead = s->port.rxBufferTail = 0;
 140     s->port.txBufferHead = s->port.txBufferTail = 0;
 141     // callback works for IRQ-based RX ONLY
 142     s->port.rxCallback = rxCallback;
 143     s->port.rxCallbackData = rxCallbackData;
 144     s->port.mode = mode;
 145     s->port.baudRate = baudRate;
 146     s->port.options = options;
 147
 148     uartReconfigure(s);
 149
 150     if (mode & MODE_RX) {
 151         USART_ClearITPendingBit(s->USARTx, USART_IT_RXNE);
 152         USART_ITConfig(s->USARTx, USART_IT_RXNE, ENABLE);
 153     }
 154
 155     if (mode & MODE_TX) {
 156         USART_ITConfig(s->USARTx, USART_IT_TXE, ENABLE);
 157     }
 158
 159     USART_Cmd(s->USARTx, ENABLE);
 160
 161     return (serialPort_t *)s;
 162 }
 163
 164 void uartSetBaudRate(serialPort_t *instance, uint32_t baudRate)
 165 {
 166     uartPort_t *uartPort = (uartPort_t *)instance;
 167     uartPort->port.baudRate = baudRate;
 168     uartReconfigure(uartPort);
 169 }
 170
 171 void uartSetMode(serialPort_t *instance, portMode_t mode)
 172 {
 173     uartPort_t *uartPort = (uartPort_t *)instance;
 174     uartPort->port.mode = mode;
 175     uartReconfigure(uartPort);
 176 }
 177
 178 uint32_t uartTotalRxBytesWaiting(const serialPort_t *instance)
 179 {
 180     const uartPort_t *s = (const uartPort_t*)instance;
 181
 182     if (s->port.rxBufferHead >= s->port.rxBufferTail) {
 183         return s->port.rxBufferHead - s->port.rxBufferTail;
 184     } else {
 185         return s->port.rxBufferSize + s->port.rxBufferHead - s->port.rxBufferTail;
 186     }
 187 }
 188
 189 uint32_t uartTotalTxBytesFree(const serialPort_t *instance)
 190 {
 191     const uartPort_t *s = (const uartPort_t*)instance;
 192
 193     uint32_t bytesUsed;
 194
 195     if (s->port.txBufferHead >= s->port.txBufferTail) {
 196         bytesUsed = s->port.txBufferHead - s->port.txBufferTail;
 197     } else {
 198         bytesUsed = s->port.txBufferSize + s->port.txBufferHead - s->port.txBufferTail;
 199     }
 200
 201     return (s->port.txBufferSize - 1) - bytesUsed;
 202 }
 203
 204 bool isUartTransmitBufferEmpty(const serialPort_t *instance)
 205 {
 206     const uartPort_t *s = (const uartPort_t *)instance;
 207     return s->port.txBufferTail == s->port.txBufferHead;
 208 }
 209
 210 uint8_t uartRead(serialPort_t *instance)
 211 {
 212     uint8_t ch;
 213     uartPort_t *s = (uartPort_t *)instance;
 214
 215     ch = s->port.rxBuffer[s->port.rxBufferTail];
 216     if (s->port.rxBufferTail + 1 >= s->port.rxBufferSize) {
 217         s->port.rxBufferTail = 0;
 218     } else {
 219         s->port.rxBufferTail++;
 220     }
 221
 222     return ch;
 223 }
 224
 225 void uartWrite(serialPort_t *instance, uint8_t ch)
 226 {
 227     uartPort_t *s = (uartPort_t *)instance;
 228     s->port.txBuffer[s->port.txBufferHead] = ch;
 229     if (s->port.txBufferHead + 1 >= s->port.txBufferSize) {
 230         s->port.txBufferHead = 0;
 231     } else {
 232         s->port.txBufferHead++;
 233     }
 234
 235     USART_ITConfig(s->USARTx, USART_IT_TXE, ENABLE);
 236 }
 237
 238 bool isUartIdle(serialPort_t *instance)
 239 {
 240     uartPort_t *s = (uartPort_t *)instance;
 241     if(USART_GetFlagStatus(s->USARTx, USART_FLAG_IDLE)) {
 242         uartClearIdleFlag(s);
 243         return true;
 244     } else {
 245         return false;
 246     }
 247 }
 248
 249 const struct serialPortVTable uartVTable[] = {
 250     {
 251         .serialWrite = uartWrite,
 252         .serialTotalRxWaiting = uartTotalRxBytesWaiting,
 253         .serialTotalTxFree = uartTotalTxBytesFree,
 254         .serialRead = uartRead,
 255         .serialSetBaudRate = uartSetBaudRate,
 256         .isSerialTransmitBufferEmpty = isUartTransmitBufferEmpty,
 257         .setMode = uartSetMode,
 258         .isConnected = NULL,
 259         .writeBuf = NULL,
 260         .beginWrite = NULL,
 261         .endWrite = NULL,
 262         .isIdle = isUartIdle,
 263     }
 264 };