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(STM32F303xC) && !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 #ifdef STM32F303xC
  56     uint32_t inversionPins = 0;
  57
  58     if (uartPort->port.mode & MODE_TX) {
  59         inversionPins |= USART_InvPin_Tx;
  60     }
  61     if (uartPort->port.mode & MODE_RX) {
  62         inversionPins |= USART_InvPin_Rx;
  63     }
  64
  65     USART_InvPinCmd(uartPort->USARTx, inversionPins, inverted ? ENABLE : DISABLE);
  66 #endif
  67 #endif
  68 }
  69
  70 static void uartReconfigure(uartPort_t *uartPort)
  71 {
  72     USART_InitTypeDef USART_InitStructure;
  73     USART_Cmd(uartPort->USARTx, DISABLE);
  74
  75     USART_InitStructure.USART_BaudRate = uartPort->port.baudRate;
  76
  77     // according to the stm32 documentation wordlen has to be 9 for parity bits
  78     // this does not seem to matter for rx but will give bad data on tx!
  79     if (uartPort->port.options & SERIAL_PARITY_EVEN) {
  80         USART_InitStructure.USART_WordLength = USART_WordLength_9b;
  81     } else {
  82         USART_InitStructure.USART_WordLength = USART_WordLength_8b;
  83     }
  84
  85     USART_InitStructure.USART_StopBits = (uartPort->port.options & SERIAL_STOPBITS_2) ? USART_StopBits_2 : USART_StopBits_1;
  86     USART_InitStructure.USART_Parity   = (uartPort->port.options & SERIAL_PARITY_EVEN) ? USART_Parity_Even : USART_Parity_No;
  87
  88     USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  89     USART_InitStructure.USART_Mode = 0;
  90     if (uartPort->port.mode & MODE_RX)
  91         USART_InitStructure.USART_Mode |= USART_Mode_Rx;
  92     if (uartPort->port.mode & MODE_TX)
  93         USART_InitStructure.USART_Mode |= USART_Mode_Tx;
  94
  95     USART_Init(uartPort->USARTx, &USART_InitStructure);
  96
  97     usartConfigurePinInversion(uartPort);
  98
  99     if (uartPort->port.options & SERIAL_BIDIR)
 100         USART_HalfDuplexCmd(uartPort->USARTx, ENABLE);
 101     else
 102         USART_HalfDuplexCmd(uartPort->USARTx, DISABLE);
 103
 104     USART_Cmd(uartPort->USARTx, ENABLE);
 105 }
 106
 107 serialPort_t *uartOpen(USART_TypeDef *USARTx, serialReceiveCallbackPtr rxCallback, void *rxCallbackData, uint32_t baudRate, portMode_t mode, portOptions_t options)
 108 {
 109     uartPort_t *s = NULL;
 110
 111     if (false) {
 112 #ifdef USE_UART1
 113     } else if (USARTx == USART1) {
 114         s = serialUART1(baudRate, mode, options);
 115
 116 #endif
 117 #ifdef USE_UART2
 118     } else if (USARTx == USART2) {
 119         s = serialUART2(baudRate, mode, options);
 120 #endif
 121 #ifdef USE_UART3
 122     } else if (USARTx == USART3) {
 123         s = serialUART3(baudRate, mode, options);
 124 #endif
 125 #ifdef USE_UART4
 126     } else if (USARTx == UART4) {
 127         s = serialUART4(baudRate, mode, options);
 128 #endif
 129 #ifdef USE_UART5
 130     } else if (USARTx == UART5) {
 131         s = serialUART5(baudRate, mode, options);
 132 #endif
 133 #ifdef USE_UART6
 134     } else if (USARTx == USART6) {
 135         s = serialUART6(baudRate, mode, options);
 136 #endif
 137 #ifdef USE_UART7
 138     } else if (USARTx == UART7) {
 139         s = serialUART7(baudRate, mode, options);
 140 #endif
 141 #ifdef USE_UART8
 142     } else if (USARTx == UART8) {
 143         s = serialUART8(baudRate, mode, options);
 144 #endif
 145
 146     } else {
 147         return (serialPort_t *)s;
 148     }
 149
 150     // common serial initialisation code should move to serialPort::init()
 151     s->port.rxBufferHead = s->port.rxBufferTail = 0;
 152     s->port.txBufferHead = s->port.txBufferTail = 0;
 153     // callback works for IRQ-based RX ONLY
 154     s->port.rxCallback = rxCallback;
 155     s->port.rxCallbackData = rxCallbackData;
 156     s->port.mode = mode;
 157     s->port.baudRate = baudRate;
 158     s->port.options = options;
 159
 160     uartReconfigure(s);
 161
 162     if (mode & MODE_RX) {
 163         USART_ClearITPendingBit(s->USARTx, USART_IT_RXNE);
 164         USART_ITConfig(s->USARTx, USART_IT_RXNE, ENABLE);
 165     }
 166
 167     if (mode & MODE_TX) {
 168         USART_ITConfig(s->USARTx, USART_IT_TXE, ENABLE);
 169     }
 170
 171     USART_Cmd(s->USARTx, ENABLE);
 172
 173     return (serialPort_t *)s;
 174 }
 175
 176 void uartSetBaudRate(serialPort_t *instance, uint32_t baudRate)
 177 {
 178     uartPort_t *uartPort = (uartPort_t *)instance;
 179     uartPort->port.baudRate = baudRate;
 180     uartReconfigure(uartPort);
 181 }
 182
 183 void uartSetMode(serialPort_t *instance, portMode_t mode)
 184 {
 185     uartPort_t *uartPort = (uartPort_t *)instance;
 186     uartPort->port.mode = mode;
 187     uartReconfigure(uartPort);
 188 }
 189
 190 uint32_t uartTotalRxBytesWaiting(const serialPort_t *instance)
 191 {
 192     const uartPort_t *s = (const uartPort_t*)instance;
 193
 194     if (s->port.rxBufferHead >= s->port.rxBufferTail) {
 195         return s->port.rxBufferHead - s->port.rxBufferTail;
 196     } else {
 197         return s->port.rxBufferSize + s->port.rxBufferHead - s->port.rxBufferTail;
 198     }
 199 }
 200
 201 uint32_t uartTotalTxBytesFree(const serialPort_t *instance)
 202 {
 203     const uartPort_t *s = (const uartPort_t*)instance;
 204
 205     uint32_t bytesUsed;
 206
 207     if (s->port.txBufferHead >= s->port.txBufferTail) {
 208         bytesUsed = s->port.txBufferHead - s->port.txBufferTail;
 209     } else {
 210         bytesUsed = s->port.txBufferSize + s->port.txBufferHead - s->port.txBufferTail;
 211     }
 212
 213     return (s->port.txBufferSize - 1) - bytesUsed;
 214 }
 215
 216 bool isUartTransmitBufferEmpty(const serialPort_t *instance)
 217 {
 218     const uartPort_t *s = (const uartPort_t *)instance;
 219     return s->port.txBufferTail == s->port.txBufferHead;
 220 }
 221
 222 uint8_t uartRead(serialPort_t *instance)
 223 {
 224     uint8_t ch;
 225     uartPort_t *s = (uartPort_t *)instance;
 226
 227     ch = s->port.rxBuffer[s->port.rxBufferTail];
 228     if (s->port.rxBufferTail + 1 >= s->port.rxBufferSize) {
 229         s->port.rxBufferTail = 0;
 230     } else {
 231         s->port.rxBufferTail++;
 232     }
 233
 234     return ch;
 235 }
 236
 237 void uartWrite(serialPort_t *instance, uint8_t ch)
 238 {
 239     uartPort_t *s = (uartPort_t *)instance;
 240     s->port.txBuffer[s->port.txBufferHead] = ch;
 241     if (s->port.txBufferHead + 1 >= s->port.txBufferSize) {
 242         s->port.txBufferHead = 0;
 243     } else {
 244         s->port.txBufferHead++;
 245     }
 246
 247     USART_ITConfig(s->USARTx, USART_IT_TXE, ENABLE);
 248 }
 249
 250 bool isUartIdle(serialPort_t *instance)
 251 {
 252     uartPort_t *s = (uartPort_t *)instance;
 253     if(USART_GetFlagStatus(s->USARTx, USART_FLAG_IDLE)) {
 254         uartClearIdleFlag(s);
 255         return true;
 256     } else {
 257         return false;
 258     }
 259 }
 260
 261 const struct serialPortVTable uartVTable[] = {
 262     {
 263         .serialWrite = uartWrite,
 264         .serialTotalRxWaiting = uartTotalRxBytesWaiting,
 265         .serialTotalTxFree = uartTotalTxBytesFree,
 266         .serialRead = uartRead,
 267         .serialSetBaudRate = uartSetBaudRate,
 268         .isSerialTransmitBufferEmpty = isUartTransmitBufferEmpty,
 269         .setMode = uartSetMode,
 270         .isConnected = NULL,
 271         .writeBuf = NULL,
 272         .beginWrite = NULL,
 273         .endWrite = NULL,
 274         .isIdle = isUartIdle,
 275     }
 276 };