stm32_buffered_uart.h

/**

stm32_buffered_uart
provides functionality to receive and send data via UART and DMA by the use of ringbuffers


MIT License

Copyright (c) 2022 Jonas Rahlf

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

*/

#pragma once

#include <stdbool.h>
#include <string.h>
#include "main.h"		// pull in ST definitions like UART_HandleTypeDef

#ifdef __cplusplus
extern "C" {
#endif


/// ==== configuration options ====

// define BUFFERED_UART_REENTRANT if you use the buffered uart API from interrupt and normal context (reentrant)
// default off
//#define BUFFERED_UART_REENTRANT

// define BUFFERED_UART_PROVIDE_HAL_UART_TxCpltCallback if the API should provide the definition for the function
// otherwise, if USE_HAL_UART_REGISTER_CALLBACKS==0 you have to call BufferedUart_TxCpltCallback from external glue code
// default on
#define BUFFERED_UART_PROVIDE_HAL_UART_TxCpltCallback

// define BUFFERED_UART_PROVIDE_HAL_UARTEx_RxEventCallback if the API should provide the definition for the function
// otherwise, if USE_HAL_UART_REGISTER_CALLBACKS==0 you have to call BufferedUart_RxEventCallback from external glue code
// default on
#define BUFFERED_UART_PROVIDE_HAL_UARTEx_RxEventCallback

// define BUFFERED_UART_PROVIDE_HAL_UART_ErrorCallback if the API should provide the definition for the function
// otherwise, if USE_HAL_UART_REGISTER_CALLBACKS==0 you have to call BufferedUart_UART_ErrorCallback from external glue code
// default on
#define BUFFERED_UART_PROVIDE_HAL_UART_ErrorCallback

// set MAX_NUMBER_BUFFERED_UARTS to the number of required number of buffered uarts
// default 1
#define MAX_NUMBER_BUFFERED_UARTS (1)

// if ALL ring buffer queue sizes are equal and known at compile time, you can specify the size here
// to enable optimization for internal modulo operations (especially if size is power of 2)
// default off
//#define BUFFERED_UART_FIXED_BUFFER_SIZE (128) //set this accordingly

/// ==== end configuration options ====

enum BufferedUartMode {
	BUFFERED_UART_TX_RX,
	BUFFERED_UART_TX,
	BUFFERED_UART_RX
};

enum DataHandledResult {
	BUFFERED_UART_DATA_NOT_HANDLED,
	BUFFERED_UART_DATA_HANDLED
};

struct BlockRingbuffer {
	char * buf;
	unsigned int head;
	unsigned int tail;
	unsigned int length;
};

struct BufferedUart {
	UART_HandleTypeDef * uart;
	struct BlockRingbuffer txqueue;
	struct BlockRingbuffer rxqueue;
	unsigned int lastSendBlockSize;
	enum DataHandledResult (*DataReceivedHandler)(const char * data, unsigned int length);
};

#ifdef BUFFERED_UART_REENTRANT
    #define BUFFERED_UART_REENTRANT_ENTER_CRITICAL_SECTION()   \
       uint32_t PriMsk;                    						\
       PriMsk = __get_PRIMASK();           						\
       __set_PRIMASK(1);

    #define BUFFERED_UART_REENTRANT_EXIT_CRITICAL_SECTION()    \
       __set_PRIMASK(PriMsk);
#else
    #define BUFFERED_UART_REENTRANT_ENTER_CRITICAL_SECTION()
    #define BUFFERED_UART_REENTRANT_EXIT_CRITICAL_SECTION()
#endif





HAL_StatusTypeDef BufferedUart_StartReception(struct BufferedUart *uart);
HAL_StatusTypeDef BufferedUart_StopReception(struct BufferedUart *uart);
HAL_StatusTypeDef BufferedUart_Init(struct BufferedUart * buffered_uart, UART_HandleTypeDef * uart, enum BufferedUartMode mode, void *txBuffer, unsigned int txSize, void *rxBuffer, unsigned int rxSize);
HAL_StatusTypeDef BufferedUart_Transmit(struct BufferedUart *uart, const void * data, unsigned int length);
HAL_StatusTypeDef BufferedUart_TransmitTimed(struct BufferedUart *uart, const void * data, unsigned int length, unsigned int timeoutMs);
unsigned int BufferedUart_Dequeue(struct BufferedUart *uart, void * buffer, unsigned int maximumLength);

#ifndef BUFFERED_UART_PROVIDE_HAL_UART_TxCpltCallback
	/// this function must be called if USE_HAL_UART_REGISTER_CALLBACKS==0
	void BufferedUart_TxCpltCallback(UART_HandleTypeDef *huart);
#endif

#ifndef BUFFERED_UART_PROVIDE_HAL_UARTEx_RxEventCallback
	/// this function must be called if USE_HAL_UART_REGISTER_CALLBACKS==0
	void BufferedUart_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size);
#endif

#ifndef BUFFERED_UART_PROVIDE_HAL_UART_ErrorCallback
	/// this function must be called if USE_HAL_UART_REGISTER_CALLBACKS==0
	void BufferedUart_UART_ErrorCallback(UART_HandleTypeDef *huart);
#endif

/**
 * Check if the buffered uart is busy sending data over the wire
 * @note while the buffered uart is busy, one can still enqueue data via the transmit functions
 * @param[in]	uart	buffered uart
 * @return		bool	true if sending data
 */
static inline bool BufferedUart_IsTXBusy(const struct BufferedUart *uart)
{
	return uart->uart->gState == HAL_UART_STATE_BUSY_TX;
}

/**
 * Similar to @ref BufferedUart_Transmit but accepts a zero terminated string as data
 */
static inline HAL_StatusTypeDef BufferedUart_TransmitString(struct BufferedUart *uart, const char * string)
{
	return BufferedUart_Transmit(uart, string, strlen(string));
}

/**
 * Similar to @ref BufferedUart_TransmitTimed but accepts a zero terminated string as data
 */
static inline HAL_StatusTypeDef BufferedUart_TransmitStringTimed(struct BufferedUart *uart, const char * string, unsigned int timeoutMs)
{
	return BufferedUart_TransmitTimed(uart, string, strlen(string), timeoutMs);
}


#ifdef __cplusplus
}
#endif