/**
  ******************************************************************************
  * @file    stm32f10x_spi.c
  * @author  MCD Application Team
  * @version V3.4.0
  * @date    10/15/2010
  * @brief   This file provides all the SPI firmware functions.
  ******************************************************************************
  * @copy
  *
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  *
  * <h2><center>&copy; COPYRIGHT 2010 STMicroelectronics</center></h2>
  */ 

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_spi.h"
#include "stm32f10x_rcc.h"

/** @addtogroup STM32F10x_StdPeriph_Driver
  * @{
  */

/** @defgroup SPI 
  * @brief SPI driver modules
  * @{
  */ 

/** @defgroup SPI_Private_TypesDefinitions
  * @{
  */

/**
  * @}
  */ 


/** @defgroup SPI_Private_Defines
  * @{
  */

/* SPI SPE mask */
#define CR1_SPE_Set          ((uint16_t)0x0040)
#define CR1_SPE_Reset        ((uint16_t)0xFFBF)

/* I2S I2SE mask */
#define I2SCFGR_I2SE_Set     ((uint16_t)0x0400)
#define I2SCFGR_I2SE_Reset   ((uint16_t)0xFBFF)

/* SPI CRCNext mask */
#define CR1_CRCNext_Set      ((uint16_t)0x1000)

/* SPI CRCEN mask */
#define CR1_CRCEN_Set        ((uint16_t)0x2000)
#define CR1_CRCEN_Reset      ((uint16_t)0xDFFF)

/* SPI SSOE mask */
#define CR2_SSOE_Set         ((uint16_t)0x0004)
#define CR2_SSOE_Reset       ((uint16_t)0xFFFB)

/* SPI registers Masks */
#define CR1_CLEAR_Mask       ((uint16_t)0x3040)
#define I2SCFGR_CLEAR_Mask   ((uint16_t)0xF040)

/* SPI or I2S mode selection masks */
#define SPI_Mode_Select      ((uint16_t)0xF7FF)
#define I2S_Mode_Select      ((uint16_t)0x0800) 

/* I2S clock source selection masks */
#define I2S2_CLOCK_SRC       ((uint32_t)(0x00020000))
#define I2S3_CLOCK_SRC       ((uint32_t)(0x00040000))
#define I2S_MUL_MASK         ((uint32_t)(0x0000F000))
#define I2S_DIV_MASK         ((uint32_t)(0x000000F0))

/**
  * @}
  */

/** @defgroup SPI_Private_Macros
  * @{
  */

/**
  * @}
  */

/** @defgroup SPI_Private_Variables
  * @{
  */

/**
  * @}
  */

/** @defgroup SPI_Private_FunctionPrototypes
  * @{
  */

/**
  * @}
  */

/** @defgroup SPI_Private_Functions
  * @{
  */

/**
  * @brief  Deinitializes the SPIx peripheral registers to their default
  *   reset values (Affects also the I2Ss).
  * @param  SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
  * @retval None
  */
void SPI_I2S_DeInit(SPI_TypeDef* SPIx)
{
  /* Check the parameters */
  assert_param(IS_SPI_ALL_PERIPH(SPIx));

  if (SPIx == SPI1)
  {
    /* Enable SPI1 reset state */
    RCC_APB2PeriphResetCmd(RCC_APB2Periph_SPI1, ENABLE);
    /* Release SPI1 from reset state */
    RCC_APB2PeriphResetCmd(RCC_APB2Periph_SPI1, DISABLE);
  }
  else if (SPIx == SPI2)
  {
    /* Enable SPI2 reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI2, ENABLE);
    /* Release SPI2 from reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI2, DISABLE);
  }
  else
  {
    if (SPIx == SPI3)
    {
      /* Enable SPI3 reset state */
      RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI3, ENABLE);
      /* Release SPI3 from reset state */
      RCC_APB1PeriphResetCmd(RCC_APB1Periph_SPI3, DISABLE);
    }
  }
}

/**
  * @brief  Initializes the SPIx peripheral according to the specified 
  *   parameters in the SPI_InitStruct.
  * @param  SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
  * @param  SPI_InitStruct: pointer to a SPI_InitTypeDef structure that
  *   contains the configuration information for the specified SPI peripheral.
  * @retval None
  */
void SPI_Init(SPI_TypeDef* SPIx, SPI_InitTypeDef* SPI_InitStruct)
{
  uint16_t tmpreg = 0;
  
  /* check the parameters */
  assert_param(IS_SPI_ALL_PERIPH(SPIx));   
  
  /* Check the SPI parameters */
  assert_param(IS_SPI_DIRECTION_MODE(SPI_InitStruct->SPI_Direction));
  assert_param(IS_SPI_MODE(SPI_InitStruct->SPI_Mode));
  assert_param(IS_SPI_DATASIZE(SPI_InitStruct->SPI_DataSize));
  assert_param(IS_SPI_CPOL(SPI_InitStruct->SPI_CPOL));
  assert_param(IS_SPI_CPHA(SPI_InitStruct->SPI_CPHA));
  assert_param(IS_SPI_NSS(SPI_InitStruct->SPI_NSS));
  assert_param(IS_SPI_BAUDRATE_PRESCALER(SPI_InitStruct->SPI_BaudRatePrescaler));
  assert_param(IS_SPI_FIRST_BIT(SPI_InitStruct->SPI_FirstBit));
  assert_param(IS_SPI_CRC_POLYNOMIAL(SPI_InitStruct->SPI_CRCPolynomial));

/*---------------------------- SPIx CR1 Configuration ------------------------*/
  /* Get the SPIx CR1 value */
  tmpreg = SPIx->CR1;
  /* Clear BIDIMode, BIDIOE, RxONLY, SSM, SSI, LSBFirst, BR, MSTR, CPOL and CPHA bits */
  tmpreg &= CR1_CLEAR_Mask;
  /* Configure SPIx: direction, NSS management, first transmitted bit, BaudRate prescaler
     master/salve mode, CPOL and CPHA */
  /* Set BIDImode, BIDIOE and RxONLY bits according to SPI_Direction value */
  /* Set SSM, SSI and MSTR bits according to SPI_Mode and SPI_NSS values */
  /* Set LSBFirst bit according to SPI_FirstBit value */
  /* Set BR bits according to SPI_BaudRatePrescaler value */
  /* Set CPOL bit according to SPI_CPOL value */
  /* Set CPHA bit according to SPI_CPHA value */
  tmpreg |= (uint16_t)((uint32_t)SPI_InitStruct->SPI_Direction | SPI_InitStruct->SPI_Mode |
                  SPI_InitStruct->SPI_DataSize | SPI_InitStruct->SPI_CPOL |  
                  SPI_InitStruct->SPI_CPHA | SPI_InitStruct->SPI_NSS |  
                  SPI_InitStruct->SPI_BaudRatePrescaler | SPI_InitStruct->SPI_FirstBit);
  /* Write to SPIx CR1 */
  SPIx->CR1 = tmpreg;
  
  /* Activate the SPI mode (Reset I2SMOD bit in I2SCFGR register) */
  SPIx->I2SCFGR &= SPI_Mode_Select;		

/*---------------------------- SPIx CRCPOLY Configuration --------------------*/
  /* Write to SPIx CRCPOLY */
  SPIx->CRCPR = SPI_InitStruct->SPI_CRCPolynomial;
}

/**
  * @brief  Initializes the SPIx peripheral according to the specified 
  *   parameters in the I2S_InitStruct.
  * @param  SPIx: where x can be  2 or 3 to select the SPI peripheral
  *   (configured in I2S mode).
  * @param  I2S_InitStruct: pointer to an I2S_InitTypeDef structure that
  *   contains the configuration information for the specified SPI peripheral
  *   configured in I2S mode.
  * @note
  *  The function calculates the optimal prescaler needed to obtain the most 
  *  accurate audio frequency (depending on the I2S clock source, the PLL values 
  *  and the product configuration). But in case the prescaler value is greater 
  *  than 511, the default value (0x02) will be configured instead.  *   
  * @retval None
  */
void I2S_Init(SPI_TypeDef* SPIx, I2S_InitTypeDef* I2S_InitStruct)
{
  uint16_t tmpreg = 0, i2sdiv = 2, i2sodd = 0, packetlength = 1;
  uint32_t tmp = 0;
  RCC_ClocksTypeDef RCC_Clocks;
  uint32_t sourceclock = 0;
  
  /* Check the I2S parameters */
  assert_param(IS_SPI_23_PERIPH(SPIx));
  assert_param(IS_I2S_MODE(I2S_InitStruct->I2S_Mode));
  assert_param(IS_I2S_STANDARD(I2S_InitStruct->I2S_Standard));
  assert_param(IS_I2S_DATA_FORMAT(I2S_InitStruct->I2S_DataFormat));
  assert_param(IS_I2S_MCLK_OUTPUT(I2S_InitStruct->I2S_MCLKOutput));
  assert_param(IS_I2S_AUDIO_FREQ(I2S_InitStruct->I2S_AudioFreq));
  assert_param(IS_I2S_CPOL(I2S_InitStruct->I2S_CPOL));  

/*----------------------- SPIx I2SCFGR & I2SPR Configuration -----------------*/
  /* Clear I2SMOD, I2SE, I2SCFG, PCMSYNC, I2SSTD, CKPOL, DATLEN and CHLEN bits */
  SPIx->I2SCFGR &= I2SCFGR_CLEAR_Mask; 
  SPIx->I2SPR = 0x0002;
  
  /* Get the I2SCFGR register value */
  tmpreg = SPIx->I2SCFGR;
  
  /* If the default value has to be written, reinitialize i2sdiv and i2sodd*/
  if(I2S_InitStruct->I2S_AudioFreq == I2S_AudioFreq_Default)
  {
    i2sodd = (uint16_t)0;
    i2sdiv = (uint16_t)2;   
  }
  /* If the requested audio frequency is not the default, compute the prescaler */
  else
  {
    /* Check the frame length (For the Prescaler computing) */
    if(I2S_InitStruct->I2S_DataFormat == I2S_DataFormat_16b)
    {
      /* Packet length is 16 bits */
      packetlength = 1;
    }
    else
    {
      /* Packet length is 32 bits */
      packetlength = 2;
    }

    /* Get the I2S clock source mask depending on the peripheral number */
    if(((uint32_t)SPIx) == SPI2_BASE)
    {
      /* The mask is relative to I2S2 */
      tmp = I2S2_CLOCK_SRC;
    }
    else 
    {
      /* The mask is relative to I2S3 */      
      tmp = I2S3_CLOCK_SRC;
    }

    /* Check the I2S clock source configuration depending on the Device:
       Only Connectivity line devices have the PLL3 VCO clock */
#ifdef STM32F10X_CL
    if((RCC->CFGR2 & tmp) != 0)
    {
      /* Get the configuration bits of RCC PLL3 multiplier */
      tmp = (uint32_t)((RCC->CFGR2 & I2S_MUL_MASK) >> 12);

      /* Get the value of the PLL3 multiplier */      
      if((tmp > 5) && (tmp < 15))
      {
        /* Multplier is between 8 and 14 (value 15 is forbidden) */
        tmp += 2;
      }
      else
      {
        if (tmp == 15)
        {
          /* Multiplier is 20 */
          tmp = 20;
        }
      }      
      /* Get the PREDIV2 value */
      sourceclock = (uint32_t)(((RCC->CFGR2 & I2S_DIV_MASK) >> 4) + 1);
      
      /* Calculate the Source Clock frequency based on PLL3 and PREDIV2 values */
      sourceclock = (uint32_t) ((HSE_Value / sourceclock) * tmp * 2); 
    }
    else
    {
      /* I2S Clock source is System clock: Get System Clock frequency */
      RCC_GetClocksFreq(&RCC_Clocks);      
      
      /* Get the source clock value: based on System Clock value */
      sourceclock = RCC_Clocks.SYSCLK_Frequency;
    }        
#else /* STM32F10X_HD */
    /* I2S Clock source is System clock: Get System Clock frequency */
    RCC_GetClocksFreq(&RCC_Clocks);      
      
    /* Get the source clock value: based on System Clock value */
    sourceclock = RCC_Clocks.SYSCLK_Frequency;    
#endif /* STM32F10X_CL */    

    /* Compute the Real divider depending on the MCLK output state with a flaoting point */
    if(I2S_InitStruct->I2S_MCLKOutput == I2S_MCLKOutput_Enable)
    {
      /* MCLK output is enabled */
      tmp = (uint16_t)(((((sourceclock / 256) * 10) / I2S_InitStruct->I2S_AudioFreq)) + 5);
    }
    else
    {
      /* MCLK output is disabled */
      tmp = (uint16_t)(((((sourceclock / (32 * packetlength)) *10 ) / I2S_InitStruct->I2S_AudioFreq)) + 5);
    }
    
    /* Remove the flaoting point */
    tmp = tmp / 10;  
      
    /* Check the parity of the divider */
    i2sodd = (uint16_t)(tmp & (uint16_t)0x0001);
   
    /* Compute the i2sdiv prescaler */
    i2sdiv = (uint16_t)((tmp - i2sodd) / 2);
   
    /* Get the Mask for the Odd bit (SPI_I2SPR[8]) register */
    i2sodd = (uint16_t) (i2sodd << 8);
  }
  
  /* Test if the divider is 1 or 0 or greater than 0xFF */
  if ((i2sdiv < 2) || (i2sdiv > 0xFF))
  {
    /* Set the default values */
    i2sdiv = 2;
    i2sodd = 0;
  }

  /* Write to SPIx I2SPR register the computed value */
  SPIx->I2SPR = (uint16_t)(i2sdiv | (uint16_t)(i2sodd | (uint16_t)I2S_InitStruct->I2S_MCLKOutput));  
 
  /* Configure the I2S with the SPI_InitStruct values */
  tmpreg |= (uint16_t)(I2S_Mode_Select | (uint16_t)(I2S_InitStruct->I2S_Mode | \
                  (uint16_t)(I2S_InitStruct->I2S_Standard | (uint16_t)(I2S_InitStruct->I2S_DataFormat | \
                  (uint16_t)I2S_InitStruct->I2S_CPOL))));
 
  /* Write to SPIx I2SCFGR */  
  SPIx->I2SCFGR = tmpreg;   
}

/**
  * @brief  Fills each SPI_InitStruct member with its default value.
  * @param  SPI_InitStruct : pointer to a SPI_InitTypeDef structure which will be initialized.
  * @retval None
  */
void SPI_StructInit(SPI_InitTypeDef* SPI_InitStruct)
{
/*--------------- Reset SPI init structure parameters values -----------------*/
  /* Initialize the SPI_Direction member */
  SPI_InitStruct->SPI_Direction = SPI_Direction_2Lines_FullDuplex;
  /* initialize the SPI_Mode member */
  SPI_InitStruct->SPI_Mode = SPI_Mode_Slave;
  /* initialize the SPI_DataSize member */
  SPI_InitStruct->SPI_DataSize = SPI_DataSize_8b;
  /* Initialize the SPI_CPOL member */
  SPI_InitStruct->SPI_CPOL = SPI_CPOL_Low;
  /* Initialize the SPI_CPHA member */
  SPI_InitStruct->SPI_CPHA = SPI_CPHA_1Edge;
  /* Initialize the SPI_NSS member */
  SPI_InitStruct->SPI_NSS = SPI_NSS_Hard;
  /* Initialize the SPI_BaudRatePrescaler member */
  SPI_InitStruct->SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2;
  /* Initialize the SPI_FirstBit member */
  SPI_InitStruct->SPI_FirstBit = SPI_FirstBit_MSB;
  /* Initialize the SPI_CRCPolynomial member */
  SPI_InitStruct->SPI_CRCPolynomial = 7;
}

/**
  * @brief  Fills each I2S_InitStruct member with its default value.
  * @param  I2S_InitStruct : pointer to a I2S_InitTypeDef structure which will be initialized.
  * @retval None
  */
void I2S_StructInit(I2S_InitTypeDef* I2S_InitStruct)
{
/*--------------- Reset I2S init structure parameters values -----------------*/
  /* Initialize the I2S_Mode member */
  I2S_InitStruct->I2S_Mode = I2S_Mode_SlaveTx;
  
  /* Initialize the I2S_Standard member */
  I2S_InitStruct->I2S_Standard = I2S_Standard_Phillips;
  
  /* Initialize the I2S_DataFormat member */
  I2S_InitStruct->I2S_DataFormat = I2S_DataFormat_16b;
  
  /* Initialize the I2S_MCLKOutput member */
  I2S_InitStruct->I2S_MCLKOutput = I2S_MCLKOutput_Disable;
  
  /* Initialize the I2S_AudioFreq member */
  I2S_InitStruct->I2S_AudioFreq = I2S_AudioFreq_Default;
  
  /* Initialize the I2S_CPOL member */
  I2S_InitStruct->I2S_CPOL = I2S_CPOL_Low;
}

/**
  * @brief  Enables or disables the specified SPI peripheral.
  * @param  SPIx: where x can be 1, 2 or 3 to select the SPI peripheral.
  * @param  NewState: new state of the SPIx peripheral. 
  *   This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void SPI_Cmd(SPI_TypeDef* SPIx, FunctionalState NewState)
{
  /* Check the parameters */
  assert_param(IS_SPI_ALL_PERIPH(SPIx));
  assert_param(IS_FUNCTIONAL_STATE(NewState));
  if (NewState != DISABLE)
  {
    /* Enable the selected SPI peripheral */
    SPIx->CR1 |= CR1_SPE_Set;
  }
  else
  {
    /* Disable the selected SPI peripheral */
    SPIx->CR1 &= CR1_SPE_Reset;
  }
}

/**
  * @brief  Enables or disables the specified SPI peripheral (in I2S mode).
  * @param  SPIx: where x can be 2 or 3 to select the SPI peripheral.
  * @param  NewState: new state of the SPIx peripheral. 
  *   This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void I2S_Cmd(SPI_TypeDef* SPIx, FunctionalState NewState)
{
  /* Check the parameters */
  assert_param(IS_SPI_23_PERIPH(SPIx));
  assert_param(IS_FUNCTIONAL_STATE(NewState));