SPI.h

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/*
 *  SPI.h - Spresense Arduino SPI library 
 *  Copyright 2018 Sony Semiconductor Solutions Corporation
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
#ifndef Spi_h
#define Spi_h
 
/*
  This header file maybe inclued in plain C file.
  To avoid compiling error all C++ stuff should be ignored
 */
// #ifdef __cplusplus
 
#include <sdk/config.h>
#include <nuttx/config.h>
#include <nuttx/spi/spi.h>
#include <Arduino.h>
 
// SPI_HAS_TRANSACTION means SPI has beginTransaction(), endTransaction(),
// usingInterrupt(), and SPISetting(clock, bitOrder, dataMode)
#define SPI_HAS_TRANSACTION 1
 
// SPI_HAS_NOTUSINGINTERRUPT means that SPI has notUsingInterrupt() method
#define SPI_HAS_NOTUSINGINTERRUPT 1
 
// SPI_ATOMIC_VERSION means that SPI has atomicity fixes and what version.
// This way when there is a bug fix you can check this define to alert users
// of your code if it uses better version of this library.
// This also implies everything that SPI_HAS_TRANSACTION as documented above is
// available too.
#define SPI_ATOMIC_VERSION 1
 
#define SPI_MODE0 SPIDEV_MODE0  
#define SPI_MODE1 SPIDEV_MODE1  
#define SPI_MODE2 SPIDEV_MODE2  
#define SPI_MODE3 SPIDEV_MODE3  
#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    
enum SpiInterruptMode {
    SPI_INT_MODE_NONE = 0,  
    SPI_INT_MODE_MASK,      
    SPI_INT_MODE_GLOBAL     
};
 
class SPISettings {
public:
    SPISettings(uint32_t clock, uint8_t bitOrder, uint8_t dataMode)
        : clock_(clock), bit_order_(bitOrder), data_mode_(dataMode) { }
 
    SPISettings()
        : clock_(4000000), bit_order_(MSBFIRST), data_mode_(SPI_MODE0) { }
 
private:
    friend class SPIClass;
    uint32_t clock_;       
    uint8_t bit_order_;    
    uint8_t data_mode_;    
};
 
class SPIClass {
public:
    SPIClass(int port);
 
    void begin(void);
 
    void end(void);
 
    void beginTransaction(SPISettings settings);
 
    void endTransaction(void);
 
    void setBitOrder(uint8_t bitOrder);
 
    void setDataMode(uint8_t dataMode);
 
    void setClockDivider(uint8_t clockDiv);
 
    void usingInterrupt(uint8_t interruptNumber);
 
    void notUsingInterrupt(uint8_t interruptNumber);
 
    uint8_t transfer(uint8_t data);
 
    uint16_t transfer16(uint16_t data);
 
    void transfer(void *buf, size_t count);
 
    void transfer16(void *buf, size_t count);
 
    void send(void *buf, size_t count);
 
    void send16(void *buf, size_t count);
 
    void selectCS(int cs);
 
    void enableCS();
 
    void disableCS();
 
private:
    int spi_port;                  
    uint8_t ref_count;             
    FAR struct spi_dev_s* spi_dev; 
    uint32_t spi_base_clock;       
    uint8_t spi_bit_order;         
    uint8_t spi_transmitting;      
    SpiInterruptMode interrupt_mode; 
    uint16_t interrupt_mask;
 
    uint16_t interrupt_save;
 
    int spi3_cs1_enable;
};
 
#if defined(CONFIG_CXD56_SPI4) && defined(CONFIG_SPI_EXCHANGE)
extern SPIClass SPI4;
 
#ifndef IS_INCLUDED_BY_SPI_CPP
extern SPIClass SPI;
#endif
 
#else
#error Please enable SPI4 and SPI_EXCHANGE in NuttX
#endif
 
#if defined(CONFIG_CXD56_SPI5) && defined(CONFIG_SPI_EXCHANGE)
extern SPIClass SPI5;
#endif
 
#if defined(CONFIG_CXD56_SPI3) && defined(CONFIG_SPI_EXCHANGE)
extern SPIClass SPI3;
#endif
 
// #endif // __cplusplus
 
#endif // Spi_h