SPIDEV.h

/*
 * The MySensors Arduino library handles the wireless radio link and protocol
 * between your home built sensors/actuators and HA controller of choice.
 * The sensors forms a self healing radio network with optional repeaters. Each
 * repeater and gateway builds a routing tables in EEPROM which keeps track of the
 * network topology allowing messages to be routed to nodes.
 *
 * Created by Henrik Ekblad <[email protected]>
 * Copyright (C) 2013-2022 Sensnology AB
 * Full contributor list: https://github.com/mysensors/MySensors/graphs/contributors
 *
 * Documentation: http://www.mysensors.org
 * Support Forum: http://forum.mysensors.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * Based on TMRh20 RF24 library, Copyright (c) 2015 Charles-Henri Hallard <[email protected]>
 */
 
#ifndef SPIDEV_h
#define SPIDEV_h
 
#include <stdint.h>
#include <string>
#include <linux/spi/spidev.h>
 
#define SPI_HAS_TRANSACTION
 
#define MSBFIRST 0
#define LSBFIRST SPI_LSB_FIRST
 
#define SPI_CLOCK_BASE 16000000     // 16Mhz
 
#define SPI_CLOCK_DIV1 1
#define SPI_CLOCK_DIV2 2
#define SPI_CLOCK_DIV4 4
#define SPI_CLOCK_DIV8 8
#define SPI_CLOCK_DIV16 16
#define SPI_CLOCK_DIV32 32
#define SPI_CLOCK_DIV64 64
#define SPI_CLOCK_DIV128 128
#define SPI_CLOCK_DIV256 256
 
// SPI Data mode
#define SPI_MODE0 SPI_MODE_0
#define SPI_MODE1 SPI_MODE_1
#define SPI_MODE2 SPI_MODE_2
#define SPI_MODE3 SPI_MODE_3
 
#ifndef SPI_SPIDEV_DEVICE
#define SPI_SPIDEV_DEVICE "/dev/spidev0.0"
#endif
 
// Default to Raspberry Pi
const uint8_t SS   = 24;
const uint8_t MOSI = 19;
const uint8_t MISO = 21;
const uint8_t SCK  = 23;
 
class SPISettings
{
 
public:
    SPISettings()
    {
        init(SPI_CLOCK_BASE, MSBFIRST, SPI_MODE0);
    }
    SPISettings(uint32_t clock, uint8_t bitOrder, uint8_t dataMode)
    {
        init(clock, bitOrder, dataMode);
    }
 
    uint32_t clock; 
    uint8_t border; 
    uint8_t dmode; 
 
private:
    void init(uint32_t clk, uint8_t bitOrder, uint8_t dataMode)
    {
        clock = clk;
        border = bitOrder;
        dmode = dataMode;
    }
 
    friend class SPIDEVClass;
};
 
class SPIDEVClass
{
 
public:
    SPIDEVClass();
    static void begin(int busNo=0);
    static void end();
    static void setBitOrder(uint8_t bit_order);
    static void setDataMode(uint8_t data_mode);
    static void setClockDivider(uint16_t divider);
    static void chipSelect(int csn_chip);
    static uint8_t transfer(uint8_t data);
    static void transfernb(char* tbuf, char* rbuf, uint32_t len);
    static void transfern(char* buf, uint32_t len);
    static void beginTransaction(SPISettings settings);
    static void endTransaction();
    static void usingInterrupt(uint8_t interruptNumber);
    static void notUsingInterrupt(uint8_t interruptNumber);
 
private:
    static uint8_t initialized; 
    static int fd; 
    static std::string device; 
    static uint8_t mode; 
    static uint32_t speed; 
    static uint8_t bit_order; 
    static struct spi_ioc_transfer tr; 
 
    static void init();
};
 
extern SPIDEVClass SPIDEV;
 
#endif