drv_serial.h

/*
   drv_serial.h : serial support for STM32F103CB

   Adapted from https://github.com/multiwii/baseflight/blob/master/src/drv_serial.h

   This file is part of BreezySTM32.

   BreezySTM32 is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   BreezySTM32 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with BreezySTM32.  If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

typedef void (*serialReceiveCallbackPtr)(uint16_t data);   // used by serial drivers to return frames to app

typedef enum portMode_t {
    MODE_RX = 1 << 0,
    MODE_TX = 1 << 1,
    MODE_RXTX = MODE_RX | MODE_TX,
    MODE_SBUS = 1 << 2
} portMode_t;

typedef struct serialPort {

    const struct serialPortVTable *vTable;

    portMode_t mode;
    uint32_t baudRate;

    uint32_t rxBufferSize;
    uint32_t txBufferSize;
    volatile uint8_t *rxBuffer;
    volatile uint8_t *txBuffer;
    uint32_t rxBufferHead;
    uint32_t rxBufferTail;
    uint32_t txBufferHead;
    uint32_t txBufferTail;

    // FIXME rename member to rxCallback
    serialReceiveCallbackPtr callback;
} serialPort_t;

struct serialPortVTable {
    void (*serialWrite)(serialPort_t *instance, uint8_t ch);

    uint8_t (*serialTotalBytesWaiting)(serialPort_t *instance);

    uint8_t (*serialRead)(serialPort_t *instance);

    // Specified baud rate may not be allowed by an implementation, use serialGetBaudRate to determine actual baud rate in use.
    void (*serialSetBaudRate)(serialPort_t *instance, uint32_t baudRate);

    bool (*isSerialTransmitBufferEmpty)(serialPort_t *instance);

    void (*setMode)(serialPort_t *instance, portMode_t mode);
};

void serialWrite(serialPort_t *instance, uint8_t ch);
uint8_t serialTotalBytesWaiting(serialPort_t *instance);
uint8_t serialRead(serialPort_t *instance);
void serialSetBaudRate(serialPort_t *instance, uint32_t baudRate);
void serialSetMode(serialPort_t *instance, portMode_t mode);
bool isSerialTransmitBufferEmpty(serialPort_t *instance);
void serialPrint(serialPort_t *instance, const char *str);
uint32_t serialGetBaudRate(serialPort_t *instance);