sta-core/include/sta/bus/spi/settings.hpp

/**
 * @file
 * @brief SPI bus settings.
 */
#ifndef STA_CORE_SPI_SETTINGS_HPP
#define STA_CORE_SPI_SETTINGS_HPP

/**
 * @defgroup sta_core_spi SPI
 * @ingroup sta_core
 * @brief SPI interface.
 */

#include <cstdint>

namespace sta
{
    /**
     * @ingroup sta_core_spi
     * @{
     */


    /**
     * @brief %SPI clock polarity.
     */
    enum class SPIClkPolarity
    {
        LOW,    /**< Low idle clock */
        HIGH    /**< High idle clock */
    };

    /**
     * @brief %SPI clock phase.
     */
    enum class SPIClkPhase
    {
        EDGE_1, /**< Sample on first edge, shift out on second edge */
        EDGE_2  /**< Shift out on first edge, sample on second edge */
    };

    /**
     * @brief %SPI clock mode.
     */
    enum class SPIMode
    {
        MODE_0,	/**< Low idle clock, sample on rising edge, shift out on falling edge */
        MODE_1,	/**< Low idle clock, sample on falling edge, shift out on rising edge */
        MODE_2,	/**< High idle clock, sample on rising edge, shift out on falling edge */
        MODE_3 	/**< High idle clock, sample on falling edge, shift out on rising edge */
    };

    /**
     * @brief %SPI data size.
     */
    enum class SPIDataSize
    {
        SIZE_8, /**< 8-bit data size */
        SIZE_16 /**< 16-bit data size */
    };

    /**
     * @brief %SPI bit order.
     */
    enum class SPIBitOrder
    {
        MSB,    /**< Send most significant bit first */
        LSB     /**< Send least significant bit first */
    };


    /**
     * @brief %SPI settings.
     */
    struct SPISettings
    {
        SPIMode     mode;       /**< %SPI clock mode */
        SPIDataSize dataSize;   /**< %SPI data size */
        SPIBitOrder bitOrder;   /**< %SPI bit order */
        uint32_t    clkSpeed;   /**< %SPI clock speed */
    };


    /**
     * @brief Get %SPI clock polarity from clock mode.
     *
     * @param mode  %SPI clock mode
     * @return      %SPI clock polarity
     */
    SPIClkPolarity getSPIClkPolarity(SPIMode mode);
    /**
     * @brief Get %SPI clock phase from clock mode.
     *
     * @param mode  %SPI clock mode
     * @return      %SPI clock phase
     */
    SPIClkPhase    getSPIClkPhase(SPIMode mode);
    /**
     * @brief Get %SPI clock mode from clock phase and polarity.
     *
     * @param polarity  %SPI clock polarity
     * @param phase     %SPI clock phase
     * @return          %SPI clock mode
     */
    SPIMode        getSPIMode(SPIClkPolarity polarity, SPIClkPhase phase);


    /** @} */
} // namespace sta


#endif // STA_CORE_SPI_SETTINGS_HPP