/**
  ******************************************************************************
  * @file    i2s_codec.c
  * @author  MCD Application Team
  * @version V4.0.0
  * @date    21-January-2013
  * @brief   This file includes the I2S Codec driver for AK4343 Audio Codec.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2013 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

#include "platform_config.h"
#ifdef USE_STM3210E_EVAL
/* Includes ------------------------------------------------------------------*/

#include "i2s_codec.h"

/* Private typedef -----------------------------------------------------------*/
typedef enum
{
  LittleEndian,
  BigEndian
}Endianness;

/* Private define ------------------------------------------------------------*/

/* Audio file header size */
#define HEADER_SIZE          100

/* EvalBoard pins related to the Codec */
#define Codec_PDN_GPIO      GPIOG
#define Codec_PDN_Pin        GPIO_Pin_11

/* Uncomment this line to enable verifying data sent to codec after each write operation */
//#define VERIFY_WRITTENDATA

/* The 7 bits Codec address mask */
#define CODEC_ADDRESS         0x27  /* b00100111 */

/* Audio Parsing Constants */
#define  ChunkID             0x52494646  /* correspond to the letters 'RIFF' */
#define  FileFormat          0x57415645  /* correspond to the letters 'WAVE' */
#define  FormatID            0x666D7420  /* correspond to the letters 'fmt ' */
#define  DataID              0x64617461  /* correspond to the letters 'data' */
#define  FactID              0x66616374  /* correspond to the letters 'fact' */

#define  WAVE_FORMAT_PCM     0x01
#define  FormatChunkSize     0x10
#define  Channel_MONO        0x01
#define  Channel_STEREO      0x02

#define  SampleRate_8000     8000
#define  SampleRate_16000    16000
#define  SampleRate_22050    22050
#define  SampleRate_44100    44100
#define  SampleRate_48000    48000
#define  Bits_Per_Sample_8   8
#define  Bits_Per_Sample_16  16

#define DUMMY_DATA           0x1111
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Audio Frequency value */
uint16_t i2saudiofreq = I2S_AudioFreq_8k;

/* Header Table containing the audio file information */
uint8_t HeaderTabIndex = 0;
uint8_t AudioFileHeader[HEADER_SIZE];

/* Audio Codec variables */
__IO uint32_t AudioFileAddress = 0x0;
uint32_t AudioDataLength = 0;//7000000;
uint32_t DataStartAddr = 0x0;
__IO uint32_t AudioDataIndex = 0;
static __IO uint32_t AudioReplay = 0xFFFF;
static uint32_t AudioReplayCount = 0xFFFF;
static __IO uint32_t SendDummyData = 0;
static __IO uint32_t AudioPlayStatus = AudioPlayStatus_STOPPED;
static uint32_t CurrentOutputDevice = OutputDevice_HEADPHONE;
static uint8_t CurrentVolume = DEFAULT_VOL;
static uint32_t errorcode = 0xFF;
static __IO uint32_t monovar = 0, tmpvar = 0;

/* Wave details names table */
WAVE_FormatTypeDef  WAVE_Format;
__IO ErrorCode  WaveFileStatus = Unvalid_RIFF_ID;

/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
static void NVIC_Config(void);
static void I2C_Config(void);
static uint32_t CODEC_WriteRegister(uint32_t RegisterAddr, uint32_t RegisterValue);
static uint32_t CODEC_ReadRegister(uint32_t RegisterAddr);
static uint32_t ReadUnit(uint8_t NbrOfBytes, Endianness BytesFormat);
uint32_t AudioFile_Init(void);

/*******************************************************************************
* Function Name  : I2S_CODEC_Init
* Description    : Initializes the I2S audio codec according parameters configured
*                    by I2S_CODEC_Config function.
* Input          : - OutputDevice: Could be OutoutDevice_SPEAKER or
*                      OutoutDevice_HEADPHONE.
*                  - Address: Specifies the location of the audio file in the memory.
* Output         : None
* Return         : - 0: if all initializations are OK.
*                  - 1: if memory initialization failed (LD2 is turned on).
*                  - 2: if audio file initialization failed (LD2 is turned on).
*                  - 3: if Codec initialization failed (LD1 is turned on).
*******************************************************************************/
uint32_t I2S_CODEC_Init(uint32_t OutputDevice, uint32_t Address)
{
  uint32_t count = 0;

  /* Set the audio file address */
  AudioFileAddress = (uint32_t) Address;

  /* Configure I2S interrupt Channel */
  NVIC_Config();

  /* Configure the I2S2, I2C1 and GPIOF pins */
  I2S_GPIO_Config();

  /* Read the Audio file to extract the audio data length and frequency */
  errorcode = AudioFile_Init();

  if (errorcode < 3)
  {
    /* Turn on LD2 connected to PF.07 */
    GPIO_SetBits(GPIOF, GPIO_Pin_7);

    return errorcode;
  }

  /* Configure the SPI2 peripheral in I2S mode */
  I2S_Config(I2S_STANDARD, I2S_MCLKOUTPUT, i2saudiofreq);

  /* Set the current output device */
  CurrentOutputDevice = OutputDevice;

  /* Codec Configuration via I2C interface */
  count = CODEC_Config(OutputDevice, I2S_STANDARD, I2S_MCLKOUTPUT, DEFAULT_VOL);

  if (count != 0)
  {
    /* Turn on LD1 connected to PF.06 */
    GPIO_SetBits(GPIOF, GPIO_Pin_6);

    return 3;
  }

  /* Turn on LD4 connected to PF.09 */
  GPIO_SetBits(GPIOF, GPIO_Pin_9);

  return 0; /* Configuration is OK */
}

/*******************************************************************************
* Function Name  : I2S_CODEC_ReplayConfig
* Description    : Set AudioReplay variable value .
* Input          : Repetions: Number of repetitions
* Output         : None
* Return         : None
*******************************************************************************/
void I2S_CODEC_ReplayConfig(uint32_t Repetions)
{
  /* Audio Replay number set by user */
  AudioReplay = Repetions;

  /* Audio Replays number remaining (if AudioReplay != 0) */
  AudioReplayCount = Repetions;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_Play
* Description    : Plays the audio file.
* Input          : - AudioStartPosition: Address from which the wave data begin
* Output         : None
* Return         : AudioDataIndex value.
*******************************************************************************/
uint32_t I2S_CODEC_Play(uint32_t AudioStartPosition)
{
  /* Send the read command to the media */
  Media_StartReadSequence(AudioFileAddress + AudioStartPosition + 1);

  /* Set Playing status to inform other modules about the codec status */
  SetVar_AudioPlayStatus(AudioPlayStatus_PLAYING);

  /* Enable the I2S2 TXE Interrupt  => Generate the clocks*/
  SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, ENABLE);

  return AudioDataIndex;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_Pause
* Description    : Pause playing the audio file.
* Input          : None
* Output         : None
* Return         : Current Position.
*******************************************************************************/
uint32_t I2S_CODEC_Pause()
{
  /* Disable the I2S2 TXE Interrupt  => stop the clocks*/
  SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, DISABLE);

  /* Set Paused status to inform other modules about the codec status */
  SetVar_AudioPlayStatus(AudioPlayStatus_PAUSED);

  /* Reset local variables */
  monovar = 0;
  tmpvar = 0;

  if (WAVE_Format.NumChannels == Channel_MONO)
  {
    /* Force the parity of the address */
    AudioDataIndex &= 0xFFFFFFFE;
  }
  /* Return the current data pointer position */
  return AudioDataIndex;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_Stop
* Description    : Stop playing the audio file, reset the pointer and power off
*                : the Codec.
* Input          : None
* Output         : None
* Return         : 0 if operation complete.
*******************************************************************************/
uint32_t I2S_CODEC_Stop()
{
  /* Disable the I2S2 TXE Interrupt  => stop the clocks */
  SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, DISABLE);

  /* Reinitialize the audio data pointer */
  AudioDataIndex = 0;

  /* Power off the Codec to save power and protect the Codec itself */
  I2S_CODEC_PowerDown(CodecPowerDown_SW);

  /* Set Paused status to inform other modules about the codec status */
  SetVar_AudioPlayStatus(AudioPlayStatus_STOPPED);

  /* Reset local variables */
  monovar = 0;
  tmpvar = 0;

  return 0;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_ControlVolume
* Description    : Controls the audio volume.
* Input          :  - direction: VolumeDirection_HIGH (0xF) to increase the volume,
*                :     VolumeDirection_LOW (0xA) to decrease  the volume or
*                :     VolumeDirection_LEVEL (0x0) to set a defined level of volume.
*                :  - Volume: the step of volume increasing/decreasing (when direction == 0)
*                :     or the volume level to be set (when direction != 0).
* Output         : None
* Return         : 0-> correct communication, else wrong communication
*******************************************************************************/
uint32_t I2S_CODEC_ControlVolume(uint32_t direction, uint8_t Volume)
{
  uint32_t counter = 0;

  if (direction == VolumeDirection_HIGH)
  {
    /* Check if the volume high limit is reached */
    if (CurrentVolume < VOLStep)
    {
      CurrentVolume = 0;
    }
    else
    {
      /* Save the current volume level */
      CurrentVolume = CODEC_ReadRegister(0x0A) - Volume;
    }

    /* Set the new volume */
    counter += CODEC_WriteRegister(0x0A, CurrentVolume);
  }
  else if (direction == VolumeDirection_LOW)
  {
    /* Check if the volume low limit is reached */
    if (CurrentVolume > (0xFF - VOLStep))
    {
      CurrentVolume = 0xFF;
    }
    else
    {
      /* Save the current volume level */
      CurrentVolume = CODEC_ReadRegister(0x0A) + Volume;
    }

    /* Set the new volume */
    counter += CODEC_WriteRegister(0x0A, CurrentVolume);
  }
  else if (direction == VolumeDirection_LEVEL)
  {
    CurrentVolume = Volume;

    /* Set the new volume */
    counter += CODEC_WriteRegister(0x0A, Volume);
  }
  else
  {
    return 0xFF; //Error verifying the Codec registers
  }

  return counter;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_Mute
* Description    : Enable or disable the MUTE mode by software
* Input          : - Command: could be MUTEON to mute sound or MUTEOFF to restore volume
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_Mute(uint32_t Command)
{
  uint32_t tmp = 0;

  /* Read the current value of the config register number 0x0E */
  tmp = CODEC_ReadRegister(0x0E);

  /* Set the Mute mode */
  if (Command == MUTE_ON)
  {
    tmp |= 0x20;
  }
  else /* MUTE_OFF Disable the Mute */
  {
    tmp &= 0xD1;
  }

  /* Write back the CODEC config register w/the new value */
  CODEC_WriteRegister(0x0E, tmp);
}

/*******************************************************************************
* Function Name  : I2S_CODEC_ForwardPlay
* Description    : Forward function.
* Input          : - Step: number of steps forward
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_ForwardPlay(uint32_t Step)
{
  /* Pause Playing the audio file */
  I2S_CODEC_Pause();

  /* Increment the Audio pointer */
  IncrementVar_AudioDataIndex((AudioDataLength / 100) * Step);

  /* Insure the index parity */
  AudioDataIndex &= 0xFFFFFFFE;

  /* Resume playing from the new position */
  I2S_CODEC_Play((GetVar_AudioDataIndex()));
}

/*******************************************************************************
* Function Name  : I2S_CODEC_RewindPlay
* Description    : Rewind function.
* Input          : - Step: number of steps back
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_RewindPlay(uint32_t Step)
{
  /* Pause Playing the audio file */
  I2S_CODEC_Pause();

  /* Increment the Audio pointer */
  DecrementVar_AudioDataIndex((AudioDataLength / 100) * Step);

  /* Insure the index parity */
  AudioDataIndex &= 0xFFFFFFFE;

  /* Resume playing from the new position */
  I2S_CODEC_Play((GetVar_AudioDataIndex()));
}

/*******************************************************************************
* Function Name  : I2S_CODEC_PowerDown
* Description    : Power down the Audio Codec.
* Input          : - CodecPowerDown_Mode: could be CodecPowerDown_SW for power down
*                :   after communication, CodecPowerDown_HW simply shut down the codec
* Output         : None
* Return         : None
*******************************************************************************/
void I2S_CODEC_PowerDown(uint32_t CodecPowerDown_Mode)
{
  if (CodecPowerDown_Mode == CodecPowerDown_SW)
  {
    /* Power down the DAC and the speaker (PMDAC and PMSPK bits)*/
    (void)CODEC_WriteRegister(0x00, 0x40);
    /* Power down the VCOM*/
    (void)CODEC_WriteRegister(0x00, 0x00);
  }
  else /* CodecPowerDown_HW */
  {
    /* Power Down the Codec */
    GPIO_ResetBits(Codec_PDN_GPIO, Codec_PDN_Pin);
  }
}

/*******************************************************************************
* Function Name  : I2S_CODEC_Reset
* Description    : Reset the Audio Codec.
* Input          : None.
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_Reset(void)
{
  /* Power Down the Codec */
  GPIO_ResetBits(Codec_PDN_GPIO, Codec_PDN_Pin);

  /* wait for a delay to allow registers erasing */
  delay(0xFF);

  /* Power On the Codec after the power off => all registers are reinitialized*/
  GPIO_SetBits(Codec_PDN_GPIO, Codec_PDN_Pin);

}

/*******************************************************************************
* Function Name  : I2S_CODEC_SpeakerHeadphoneSwap
* Description    : Configure the Audio Codec output to Speaker or Headphone while
*                : the audio wave is Paused or stopped.
* Input          : - OutputDevice: could be OutputDevice_Speaker or OutputDevice_Headphone
*                     or OutputDevice_Both .
*                  - Address: Specifies the audio file location in the memory.
* Output         : None.
* Return         : - 0: Operation done without failures.
*                  - 1: Memory failure occur.
*                  - 2: Audio file initialization failure occur
*                  - 3: I2C communication failure occur
*******************************************************************************/
uint32_t I2S_CODEC_SpeakerHeadphoneSwap(uint32_t OutputDevice, uint32_t Address)
{
  uint32_t tmp_pointer = 0, err = 0;

  /* Reset all Codec Registers */
  I2S_CODEC_Reset();

  /* Save the current position */
  tmp_pointer = GetVar_AudioDataIndex();

  /* Reinitialize the CODEC with the new configured parameters */
  err = I2S_CODEC_Init(OutputDevice, Address);

  if (err != 0)
  {
    return err;
  }

  /* Restore the last pointer position */
  AudioDataIndex = tmp_pointer;

  /* Restore the last volume level */
  I2S_CODEC_ControlVolume(VolumeDirection_LEVEL, CurrentVolume);

  /* Play from current position */
  I2S_CODEC_Play(tmp_pointer);

  return 0;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_UpdateStatus
* Description    : Check if STOP or PAUSE command are generated and performs the
*                :  relative action (STOP or PAUSE playing)
* Input          : None.
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_UpdateStatus(void)
{
  /* STOP command is generated => Stop playing the audio file */
  if ((GetVar_AudioPlayStatus() == AudioPlayStatus_STOPPED) && (SPI_I2S_GetFlagStatus(SPI2, I2S_FLAG_CHSIDE) == SET))
  {
    I2S_CODEC_Stop();
  }

  /* PAUSE Command is generated => PAUSE playing the audio File */
  if ((GetVar_AudioPlayStatus() == AudioPlayStatus_PAUSED) && (SPI_I2S_GetFlagStatus(SPI2, I2S_FLAG_CHSIDE) == SET))
  {
    I2S_CODEC_Pause();
  }
}

/*******************************************************************************
* Function Name  : GetVar_DataStartAddr
* Description    : returns DataStartAddr variable value (used by stm32f10x_it.c file).
* Input          : None
* Output         : None
* Return         : AudioDataIndex
*******************************************************************************/
uint32_t GetVar_DataStartAddr(void)
{
  return DataStartAddr;
}


/*******************************************************************************
* Function Name  : GetVar_CurrentVolume
* Description    : returns CurrentVolume variable value (used by extern files).
* Input          : None
* Output         : None
* Return         : CurrentVolume
*******************************************************************************/
uint8_t GetVar_CurrentVolume(void)
{
  return CurrentVolume;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_WaveParsing
* Description    : Checks the format of the .WAV file and gets information about
*                  the audio format. This is done by reading the value of a
*                  number of parameters stored in the file header and comparing
*                  these to the values expected authenticates the format of a
*                  standard .WAV  file (44 bytes will be read). If  it is a valid
*                  .WAV file format, it continues reading the header to determine
*                  the  audio format such as the sample rate and the sampled data
*                  size. If the audio format is supported by this application,
*                  it retrieves the audio format in WAVE_Format structure and
*                  returns a zero value. Otherwise the function fails and the
*                  return value is nonzero.In this case, the return value specifies
*                  the cause of  the function fails. The error codes that can be
*                  returned by this function are declared in the header file.
* Input          : None
* Output         : None
* Return         : Zero value if the function succeed, otherwise it return
*                  a nonzero value which specifies the error code.
*******************************************************************************/
ErrorCode I2S_CODEC_WaveParsing(uint8_t* HeaderTab)
{
  uint32_t Temp = 0x00;
  uint32_t ExtraFormatBytes = 0;

  /* Initialize the HeaderTabIndex variable */
  HeaderTabIndex = 0;

  /* Read chunkID, must be 'RIFF' ----------------------------------------------*/
  Temp = ReadUnit(4, BigEndian);
  if (Temp != ChunkID)
  {
    return(Unvalid_RIFF_ID);
  }
  /* Read the file length ----------------------------------------------------*/
  WAVE_Format.RIFFchunksize = ReadUnit(4, LittleEndian);

  /* Read the file format, must be 'WAVE' ------------------------------------*/
  Temp = ReadUnit(4, BigEndian);
  if (Temp != FileFormat)
  {
    return(Unvalid_WAVE_Format);
  }
  /* Read the format chunk, must be 'fmt ' -----------------------------------*/
  Temp = ReadUnit(4, BigEndian);
  if (Temp != FormatID)
  {
    return(Unvalid_FormatChunk_ID);
  }
  /* Read the length of the 'fmt' data, must be 0x10 -------------------------*/
  Temp = ReadUnit(4, LittleEndian);
  if (Temp != 0x10)
  {
    ExtraFormatBytes = 1;
  }
  /* Read the audio format, must be 0x01 (PCM) -------------------------------*/
  WAVE_Format.FormatTag = ReadUnit(2, LittleEndian);
  if (WAVE_Format.FormatTag != WAVE_FORMAT_PCM)
  {
    return(Unsupporetd_FormatTag);
  }
  /* Read the number of channels: 0x02->Stereo 0x01->Mono --------------------*/
  WAVE_Format.NumChannels = ReadUnit(2, LittleEndian);

  /* Read the Sample Rate ----------------------------------------------------*/
  WAVE_Format.SampleRate = ReadUnit(4, LittleEndian);

  /* Update the I2S_AudioFreq value according to the .WAV file Sample Rate */
  switch (WAVE_Format.SampleRate)
  {
    case SampleRate_8000 :
      i2saudiofreq = I2S_AudioFreq_8k;
      break;
    case SampleRate_16000:
      i2saudiofreq = I2S_AudioFreq_16k;
      break;
    case SampleRate_22050:
      i2saudiofreq = I2S_AudioFreq_22k;
      break;
    case SampleRate_44100:
      i2saudiofreq = I2S_AudioFreq_44k;
      break;
    case SampleRate_48000:
      i2saudiofreq = I2S_AudioFreq_48k;
      break;
    default:
      return(Unsupporetd_Sample_Rate);
  }
  /* Read the Byte Rate ------------------------------------------------------*/
  WAVE_Format.ByteRate = ReadUnit(4, LittleEndian);

  /* Read the block alignment ------------------------------------------------*/
  WAVE_Format.BlockAlign = ReadUnit(2, LittleEndian);

  /* Read the number of bits per sample --------------------------------------*/
  WAVE_Format.BitsPerSample = ReadUnit(2, LittleEndian);
  if (WAVE_Format.BitsPerSample != Bits_Per_Sample_16)
  {
    return(Unsupporetd_Bits_Per_Sample);
  }
  /* If there are Extra format bytes, these bytes will be defined in "Fact Chunk" */
  if (ExtraFormatBytes == 1)
  {
    /* Read th Extra format bytes, must be 0x00 ------------------------------*/
    Temp = ReadUnit(2, LittleEndian);
    if (Temp != 0x00)
    {
      return(Unsupporetd_ExtraFormatBytes);
    }
    /* Read the Fact chunk, must be 'fact' -----------------------------------*/
    Temp = ReadUnit(4, BigEndian);
    if (Temp != FactID)
    {
      return(Unvalid_FactChunk_ID);
    }
    /* Read Fact chunk data Size ---------------------------------------------*/
    Temp = ReadUnit(4, LittleEndian);

    /* Set the index to start reading just after the header end */
    HeaderTabIndex += Temp;
  }
  /* Read the Data chunk, must be 'data' -------------------------------------*/
  Temp = ReadUnit(4, BigEndian);
  if (Temp != DataID)
  {
    return(Unvalid_DataChunk_ID);
  }
  /* Read the number of sample data ------------------------------------------*/
  WAVE_Format.DataSize = ReadUnit(4, LittleEndian);

  /* Set the data pointer at the beginning of the effective audio data */
  DataStartAddr += HeaderTabIndex;

  return(Valid_WAVE_File);
}

/*******************************************************************************
* Function Name  : GetVar_AudioDataIndex
* Description    : returns AudioDataIndex variable value (used by stm32f10x_it.c file).
* Input          : None
* Output         : None
* Return         : AudioDataIndex
*******************************************************************************/
uint32_t GetVar_AudioDataIndex(void)
{
  return AudioDataIndex;
}

/*******************************************************************************
* Function Name  : SetVar_AudioDataIndex
* Description    : Sets AudioDataIndex variable value (used by stm32f10x_it.c file).
* Input          : None
* Output         : None
* Return         : AudioDataIndex
*******************************************************************************/
void SetVar_AudioDataIndex(uint32_t value)
{
  AudioDataIndex = value;
}

/*******************************************************************************
* Function Name  : IncrementVar_AudioDataIndex
* Description    : Increment the AudioDataIndex variable.
* Input          : - IncrementNumber: number of incrementations.
* Output         : None
* Return         : None
*******************************************************************************/
void IncrementVar_AudioDataIndex(uint32_t IncrementNumber)
{
  AudioDataIndex += (uint32_t)IncrementNumber;

  if (AudioDataIndex >= AudioDataLength)
  {
    ResetVar_AudioDataIndex();
    Decrement_AudioReplay();
  }
}

/*******************************************************************************
* Function Name  : DecrementVar_AudioDataIndex
* Description    : Set the AudioDataIndex variable to 1.
* Input          : None
* Output         : None
* Return         : None.
*******************************************************************************/
void DecrementVar_AudioDataIndex(uint32_t DecrementNumber)
{
  if (DecrementNumber >= AudioDataIndex)
  {
    ResetVar_AudioDataIndex();
  }
  else
  {
    AudioDataIndex -= (uint32_t)DecrementNumber;
  }
}

/*******************************************************************************
* Function Name  : ResetVar_AudioDataIndex
* Description    : Reset the AudioDataIndex variable.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void ResetVar_AudioDataIndex(void)
{
  AudioDataIndex = DataStartAddr;

  /* Send the read command to the media */
  Media_StartReadSequence(AudioFileAddress + DataStartAddr + 1);
}

/*******************************************************************************
* Function Name  : GetVar_SendDummyData
* Description    : returns SendDummyData variable value (used by stm32f10x_it.c file).
* Input          : None
* Output         : None
* Return         : SendDummyData
*******************************************************************************/
uint32_t GetVar_SendDummyData(void)
{
  return SendDummyData;
}

/*******************************************************************************
* Function Name  : SetVar_SendDummyData
* Description    : Set the SendDummyData variable to 1.
* Input          : None
* Output         : None
* Return         : SendDummyData
*******************************************************************************/
uint32_t SetVar_SendDummyData(void)
{
  SendDummyData = (uint32_t)0x1;

  return SendDummyData;
}

/*******************************************************************************
* Function Name  : ResetVar_SendDummyData
* Description    : Reset the SendDummyData variable to 0.
* Input          : None
* Output         : None
* Return         : SendDummyData
*******************************************************************************/
uint32_t ResetVar_SendDummyData(void)
{
  SendDummyData = (uint32_t)0;

  return SendDummyData;
}

/*******************************************************************************
* Function Name  : GetVar_AudioPlayStatus
* Description    : returns AudioPlayStatus variable value (used by stm32f10x_it.c file).
* Input          : None
* Output         : None
* Return         : AudioPlayStatus value.
*******************************************************************************/
uint32_t GetVar_AudioPlayStatus(void)
{
  return AudioPlayStatus;
}

/*******************************************************************************
* Function Name  : SetVar_AudioPlayStatus
* Description    : Set the AudioDataIndex variable to Status.
* Input          : Status: could be AudioPlayStatus_STOPPED, AudioPlayStatus_PLAYING
*                :        or AudioPlayStatus_PAUSED.
* Output         : None
* Return         : AudioPlayStatus value.
*******************************************************************************/
uint32_t SetVar_AudioPlayStatus(uint32_t Status)
{
  AudioPlayStatus = (uint32_t)Status;

  return AudioPlayStatus;
}

/*******************************************************************************
* Function Name  : GetVar_AudioReplay
* Description    : returns AudioReplay variable value.
* Input          : None
* Output         : None
* Return         : AudioReplay value.
*******************************************************************************/
uint32_t GetVar_AudioReplay(void)
{
  return AudioReplay;
}

/*******************************************************************************
* Function Name  : SetVar_AudioReplay
* Description    : Decrement the AudioReplayCount variable if AudioReplay is different
*                :  from zero (infinite replaying).
* Input          : None.
* Output         : None
* Return         : AudioPlayStatus value.
*******************************************************************************/
void Decrement_AudioReplay(void)
{
  if (AudioReplay != 0)
  {
    AudioReplayCount--;

    if (AudioReplayCount == 0)
    {
      /* Command the Stop of the audio playing */
      SetVar_AudioPlayStatus(AudioPlayStatus_STOPPED);

      /* Reset the counter */
      AudioReplayCount = AudioReplay;
    }
  }
}

/*******************************************************************************
* Function Name  : GetVar_CurrentOutputDevice
* Description    : Get the current output device selected .
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
uint32_t GetVar_CurrentOutputDevice(void)
{
  return CurrentOutputDevice;
}

/*******************************************************************************
* Function Name  : GetVar_AudioDataLength
* Description    : Get the current audio file data length .
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
uint32_t GetVar_AudioDataLength(void)
{
  return AudioDataLength;
}

/*******************************************************************************
* Function Name  : GetVar_i2saudiofreq
* Description    : Get the current audio frequency .
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
uint16_t GetVar_i2saudiofreq(void)
{
  return i2saudiofreq;
}

/*******************************************************************************
* Function Name  : AudioFile_Init
* Description    : Initializes the SPI_Flash and returns the Wavadatalength variable.
* Input          : None
* Output         : None
* Return         : - The length of the wave file read from the SPI_Flash
*                  - 1 if an error occurred when initializing the memory.
*                  - 2 if an error occurred on the audio file initialization.
*******************************************************************************/
uint32_t AudioFile_Init(void)
{
  uint32_t err = 0;

  /* Initialize the media support */
  err = Media_Init();

  /* Check if Memory initialization is OK */
  if (err != 0)
  {
    return 1;
  }

  /* Read a Byte buffer and store it in the Header table*/
  Media_BufferRead(AudioFileHeader, AudioFileAddress, HEADER_SIZE);

  /* Read and check the audio file Header */
  WaveFileStatus = I2S_CODEC_WaveParsing(AudioFileHeader);

  /* Check if the selected file is a correct wave file */
  if (WaveFileStatus == Valid_WAVE_File)
  {
    /* Read and set the audio data length (/!\ data are counted as BYTES /!\) */
    AudioDataLength = WAVE_Format.DataSize ;

    /* Read and set the audio frequency */
    i2saudiofreq = (uint16_t)WAVE_Format.SampleRate;

    /* Return the audio file length */
    return AudioDataLength;
  }
  else /* Wrong wave file */
  {
    return 2;
  }
}

/*******************************************************************************
* Function Name  : NVIC_Config
* Description    : Configure the I2Ss NVIC channel.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
static void NVIC_Config(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;

  /* SPI2 IRQ Channel configuration */
  NVIC_InitStructure.NVIC_IRQChannel = SPI2_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

/*******************************************************************************
* Function Name  : GPIO_Config
* Description    : Initializes the GPIO pins used by the codec application.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void I2S_GPIO_Config(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

  /* Enable GPIOB, GPIOC and AFIO clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOG |
                         RCC_APB2Periph_GPIOF | RCC_APB2Periph_AFIO, ENABLE);

  /* I2S2 SD, CK and WS pins configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  /* I2S2 MCK pin configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_Init(GPIOC, &GPIO_InitStructure);

  /* LEDs pins configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_Init(GPIOF, &GPIO_InitStructure);

  /* I2C1 SCL PB6 and SDA PB7 pins configuration */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  /* Enable the I2C1 APB1 clock */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

  /* Turn Off All LEDs */
  GPIO_ResetBits(GPIOF, GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9);
  GPIO_ResetBits(Codec_PDN_GPIO, Codec_PDN_Pin);

  /* Configure the Codec PDN pin as output PushPull */
  GPIO_InitStructure.GPIO_Pin = Codec_PDN_Pin;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_Init(Codec_PDN_GPIO, &GPIO_InitStructure);
}

/*******************************************************************************
* Function Name  : I2S_Config
* Description    : Configure the I2S Peripheral.
* Input          :  - Standard: I2S_Standard_Phillips, I2S_Standard_MSB or I2S_Standard_LSB
*                   - MCLKOutput: I2S_MCLKOutput_Enable or I2S_MCLKOutput_Disable
*                   - AudioFreq: I2S_AudioFreq_8K, I2S_AudioFreq_16K, I2S_AudioFreq_22K,
*                                I2S_AudioFreq_44K or I2S_AudioFreq_48K
* Output         : None
* Return         : None
*******************************************************************************/
void I2S_Config(uint16_t Standard, uint16_t MCLKOutput, uint16_t AudioFreq)
{
  I2S_InitTypeDef I2S_InitStructure;

  /* Enable I2S2 APB1 clock */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);

  /* Deinitialize SPI2 peripheral */
  SPI_I2S_DeInit(SPI2);

  /* I2S2 peripheral configuration */
  I2S_InitStructure.I2S_Mode = I2S_Mode_MasterTx;
  I2S_InitStructure.I2S_Standard = Standard;
  I2S_InitStructure.I2S_DataFormat = I2S_DataFormat_16b;
  I2S_InitStructure.I2S_MCLKOutput = MCLKOutput;
  I2S_InitStructure.I2S_AudioFreq = AudioFreq;
  I2S_InitStructure.I2S_CPOL = I2S_CPOL_Low;
  I2S_Init(SPI2, &I2S_InitStructure);

  /* Disable the I2S2 TXE Interrupt */
  SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, DISABLE);

  /* Enable the SPI2/I2S2 peripheral */
  I2S_Cmd(SPI2, ENABLE);
}

/*******************************************************************************
* Function Name  : I2C_Config
* Description    : Configure the I2C1 Peripheral.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
static void I2C_Config(void)
{
  I2C_InitTypeDef I2C_InitStructure;

  /* I2C1 configuration */
  I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
  I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
  I2C_InitStructure.I2C_OwnAddress1 = 0x33;
  I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
  I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
  I2C_InitStructure.I2C_ClockSpeed = 200000;
  I2C_Init(I2C1, &I2C_InitStructure);
}

/*******************************************************************************
* Function Name  : CODEC_Config
* Description    : Configure the Codec in Headphone mode.
* Input          :  - OutputDevice: OutputDeviceHEADPHONE or OutputDeviceSPEAKER
*                :  - I2S_Standard: I2S communication standard could be I2S_Standard_Phillips
*                :       I2S_Standard_MSB or I2S_Standard_LSB.
*                :  - I2S_MCLKOutput: could be I2S_MCLKOutput_
*                :  - Volume:
* Output         : None
* Return         : 0-> correct communication, else wrong communication
*******************************************************************************/
uint32_t CODEC_Config(uint16_t OutputDevice, uint16_t I2S_Standard, uint16_t I2S_MCLKOutput, uint8_t Volume)
{
  uint32_t Standard = 0, counter = 0, PLLMode = 0;

  /* Command the sending of dummy data */
  ResetVar_SendDummyData();

  /* Reset the Codec Registers */
  I2S_CODEC_Reset();

  /* Determine the I2S standard used */
  switch (I2S_Standard)
  {
    case I2S_Standard_Phillips:
      Standard = 0x03;
      break;
    case I2S_Standard_MSB:
      Standard = 0x02;
      break;
    default :
      Standard = 0x01;
      break;
  }

  /* HEADPHONE codec configuration */
  if ((OutputDevice & OutputDevice_HEADPHONE) != 0)
  {
    /* PLL Slave SD/WS reference mode ----------------------*/
    if (I2S_MCLKOutput == I2S_MCLKOutput_Disable)
    {
      /* set the PLLMode variable */
      PLLMode = 0x1;

      /* Phillips(0x03)/MSB(0x02)/LSB(0x01) mode with PLL */
      counter += CODEC_WriteRegister(0x04, (Standard | 0x20));
      /* MCKI input frequency = 256.Fs */
      counter += CODEC_WriteRegister(0x05, 0x03);
      /* VCOM Power up (PMVCM bit)*/
      counter += CODEC_WriteRegister(0x00, 0x40);
      /* Enable PLL*/
      counter += CODEC_WriteRegister(0x01, 0x01);
    }
    /* Ext Slave mode with no PLL --------------------------*/
    else
    {
      /* Reset the PLL mode variable */
      PLLMode = 0;

      /* Phillips(0x03)/MSB(0x02)/LSB(0x01) mode with no PLL */
      counter += CODEC_WriteRegister(0x04, Standard);
      /* MCKI input frequency = 256.Fs */
      counter += CODEC_WriteRegister(0x05, 0x00);
      /* VCOM Power up (PMVCM bit)*/
      counter += CODEC_WriteRegister(0x00, 0x40);
    }

    /* Command the sending of dummy data */
    SetVar_SendDummyData();

    /* Enable the I2S2 TXE Interrupt  => Generate the clocks*/
    SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, ENABLE);

    /* Extra Configuration (of the ALC) */
    counter += CODEC_WriteRegister(0x06, 0x3C );
    counter += CODEC_WriteRegister(0x08, 0xE1 );
    counter += CODEC_WriteRegister(0x0B, 0x00 );
    counter += CODEC_WriteRegister(0x07, 0x20 );
    counter += CODEC_WriteRegister(0x09, 0xC1 );
    counter += CODEC_WriteRegister(0x0C, 0xC1 );

    /* MCKI is 256.Fs with no PLL */
    counter += CODEC_WriteRegister(0x05, 0x00 );
    /* Switch control from DAC to Headphone */
    counter += CODEC_WriteRegister(0x0F, 0x09 );
    /* Bass Boost and Deemphasis enable */
    counter += CODEC_WriteRegister(0x0E, 0x18 );
    /* Left Channel Digital Volume control */
    counter += CODEC_WriteRegister(0x0A, Volume);
    /* Right Channel Digital Volume control */
    counter += CODEC_WriteRegister(0x0D, Volume);
    /* Power up MIN and DAC (PMMIN and PMDAC bits)*/
    counter += CODEC_WriteRegister(0x00, 0x74);
    /* Enable Slave mode and Left/Right HP lines*/
    counter += CODEC_WriteRegister(0x01, (0x30 | PLLMode));
    /* Exit HP mute mode */
    counter += CODEC_WriteRegister(0x01, (0x70 | PLLMode));
  }

  /* SPEAKER codec configuration */
  if ((OutputDevice & OutputDevice_SPEAKER) != 0)
  {
    /* PLL Slave SD/WS reference mode ----------------------*/
    if (I2S_MCLKOutput == I2S_MCLKOutput_Disable)
    {
      /* Phillips(0x03)/MSB(0x02)/LSB(0x01) mode with no PLL */
      counter += CODEC_WriteRegister(0x04, (Standard | 0x20));
      /* MCKI input frequency = 256.Fs */
      counter += CODEC_WriteRegister(0x05, 0x03);
      /* VCOM Power up (PMVCM bit)*/
      counter += CODEC_WriteRegister(0x00, 0x40);
      /* Enable PLL*/
      counter += CODEC_WriteRegister(0x01, 0x01);
    }
    /* Ext Slave mode with no PLL --------------------------*/
    else
    {
      /* Phillips(0x03)/MSB(0x02)/LSB(0x01) mode with no PLL */
      counter += CODEC_WriteRegister(0x04, Standard);
      /* MCKI input frequency = 256.Fs */
      counter += CODEC_WriteRegister(0x05, 0x00);
      /* VCOM Power up (PMVCM bit)*/
      counter += CODEC_WriteRegister(0x00, 0x40);
    }

    /* Command the sending of dummy data */
    SetVar_SendDummyData();

    /* Enable the I2S2 TXE Interrupt  => Generate the clocks*/
    SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, ENABLE);

    /* ReSelect the MCKI frequency (FS0-1 bits): 256.Fs */
    counter += CODEC_WriteRegister(0x05, 0x02 );
    /* Set up the path "DAC->Speaker-Amp" with no power save (DACS and SPPSN bits) */
    counter += CODEC_WriteRegister(0x02, 0x20 );
    /* Speaker Gain (SPKG0-1 bits): Gain=+10.65dB(ALC off)/+12.65(ALC on) */
    counter += CODEC_WriteRegister(0x03, 0x10);

    /* Extra Configuration (of the ALC) */
    counter += CODEC_WriteRegister(0x06, 0x3C );
    counter += CODEC_WriteRegister(0x08, 0xE1 );
    counter += CODEC_WriteRegister(0x0B, 0x00 );
    counter += CODEC_WriteRegister(0x07, 0x20 );
    counter += CODEC_WriteRegister(0x09, 0x91 );
    counter += CODEC_WriteRegister(0x0C, 0x91 );

    /* Left Channel Digital Volume control */
    counter += CODEC_WriteRegister(0x0A, Volume);
    /* Right Channel Digital Volume control */
    counter += CODEC_WriteRegister(0x0D, Volume);
    /* Power up Speaker and DAC (PMSPK and PMDAC bits)*/
    counter += CODEC_WriteRegister(0x00, 0x54);
    /* Set up the path "DAC -> Speaker-Amp" with no power save */
    counter += CODEC_WriteRegister(0x02, 0xA0 /*0xA1*/);
  }

  /* Disable the I2S2 TXE Interrupt */
  SPI_I2S_ITConfig(SPI2, SPI_I2S_IT_TXE, DISABLE);

  /* Disable the sending of Dummy data */
  ResetVar_SendDummyData();

  /* Return the counter value */
  return counter;
}

/*******************************************************************************
* Function Name  : CODEC_WriteRegister
* Description    : Writes a value in a register of the audio Codec through I2C.
* Input          :  - RegisterAddr: The target register address (between 00x and 0x24)
*                :  - RegisterValue: The target register value to be written
*                :  - Verify: 0-> Don't verify the written data, 1-> Verify the written data
* Output         : None
* Return         : - 0  -> Correct write operation
*                : - !0 -> Incorrect write operation
*******************************************************************************/
uint32_t CODEC_WriteRegister(uint32_t RegisterAddr, uint32_t RegisterValue)
{
  uint32_t read_verif = 0;

  /* Reset all I2C2 registers */
  I2C_SoftwareResetCmd(I2C1, ENABLE);
  I2C_SoftwareResetCmd(I2C1, DISABLE);

  /* Enable the I2C1 peripheral  */
  I2C_Cmd(I2C1, ENABLE);

  /* Configure the I2C peripheral */
  I2C_Config();

  /* Begin the config sequence */
  I2C_GenerateSTART(I2C1, ENABLE);

  /* Test on EV5 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))
  {}
  /* Transmit the slave address and enable writing operation */
  I2C_Send7bitAddress(I2C1, CODEC_ADDRESS, I2C_Direction_Transmitter);

  /* Test on EV6 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
  {}
  /* Transmit the first address for r/w operations */
  I2C_SendData(I2C1, RegisterAddr);

  /* Test on EV8 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
  {}

  /* Prepare the register value to be sent */
  I2C_SendData(I2C1, RegisterValue);

  /* Test on EV8 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
  {}

  /* End the configuration sequence */
  I2C_GenerateSTOP(I2C1, ENABLE);

  /* Verify (if needed) that the loaded data is correct  */
#ifdef VERIFY_WRITTENDATA
  /* Read the just written register*/
  read_verif = CODEC_ReadRegister(RegisterAddr);

  /* Load the register and verify its value  */
  if (read_verif != RegisterValue)
  {
    /* Control data wrongly transferred */
    read_verif = 1;
  }
  else
  {
    /* Control data correctly transferred */
    read_verif = 0;
  }
#endif

  /* Return the verifying value: 0 (Passed) or 1 (Failed) */
  return read_verif;
}

/*******************************************************************************
* Function Name  : CODEC_ReadRegister
* Description    : Reads a register of the audio Codec through I2C.
* Input          :  - RegisterAddr: The target register address (between 00x and 0x24)
* Output         : None
* Return         : The value of the read register
*******************************************************************************/
uint32_t CODEC_ReadRegister(uint32_t RegisterAddr)
{
  uint32_t tmp = 0;

  /* Disable the I2C1 peripheral  */
  I2C_Cmd(I2C1, DISABLE);

  /* Reset all I2C2 registers */
  I2C_SoftwareResetCmd(I2C1, ENABLE);
  I2C_SoftwareResetCmd(I2C1, DISABLE);

  /* Configure the I2C peripheral */
  I2C_Config();

  /* Enable the I2C peripheral */
  I2C_GenerateSTART(I2C1, ENABLE);

  /* Test on EV5 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))
  {}

  /* Disable Acknowledgement */
  I2C_AcknowledgeConfig(I2C1, DISABLE);

  /* Transmit the slave address and enable writing operation */
  I2C_Send7bitAddress(I2C1, CODEC_ADDRESS, I2C_Direction_Transmitter);

  /* Test on EV6 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
  {}

  /* Transmit the first address for r/w operations */
  I2C_SendData(I2C1, RegisterAddr);

  /* Test on EV8 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
  {}

  /* Regenerate a start condition */
  I2C_GenerateSTART(I2C1, ENABLE);

  /* Test on EV5 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))
  {}

  /* Transmit the slave address and enable writing operation */
  I2C_Send7bitAddress(I2C1, CODEC_ADDRESS, I2C_Direction_Receiver);

  /* Test on EV6 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))
  {}

  /* Test on EV7 and clear it */
  while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED))
  {}

  /* End the configuration sequence */
  I2C_GenerateSTOP(I2C1, ENABLE);

  /* Load the register value */
  tmp = I2C_ReceiveData(I2C1);

  /* Disable Acknowledgement */
  I2C_AcknowledgeConfig(I2C1, ENABLE);

  /* Return the read value */
  return tmp;
}

/*******************************************************************************
* Function Name  : ReadUnit
* Description    : Reads a number of bytes from the SPI Flash and reorder them
*                  in Big or little endian.
* Input          : - NbrOfBytes : number of bytes to read.
*                    This parameter must be a number between 1 and 4.
*                  - ReadAddr : external memory address to read from.
*                  - Endians : specifies the bytes endianness.
*                    This parameter can be one of the following values:
*                          - LittleEndian
*                          - BigEndian
* Output         : None
* Return         : Bytes read from the SPI Flash.
*******************************************************************************/
static uint32_t ReadUnit(uint8_t NbrOfBytes, Endianness BytesFormat)
{
  uint32_t index = 0;
  uint32_t Temp = 0;

  if (BytesFormat == LittleEndian)
  {
    for (index = 0; index < NbrOfBytes; index++)
    {
      Temp |= AudioFileHeader[HeaderTabIndex++] << (index * 8);
    }
  }
  else
  {
    for (index = NbrOfBytes; index != 0; index--)
    {
      Temp |= AudioFileHeader[HeaderTabIndex++] << ((index - 1) * 8);
    }
  }

  return Temp;
}

/*******************************************************************************
* Function Name  : I2S_CODEC_MediaReadHalfWord
* Description    : Read one half word from the media (SPI_Flash/NOR/NAND memories..)
* Input          : - Offset: the address offset for read operation
* Output         : None.
* Return         : Data read from the media memory.
*******************************************************************************/
uint16_t Media_ReadHalfWord(uint32_t Offset)
{
  /* Test if the left channel is to be sent */
  if (monovar == 0)
  {
    /* Enable the FSMC that share a pin w/ I2C1 (LBAR) */
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, ENABLE);

    tmpvar =  (*(__IO uint16_t *) (AudioFileAddress + Offset));

    /* Disable the FSMC that share a pin w/ I2C1 (LBAR) */
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, DISABLE);

    /* Increment the mono variable only if the file is in mono format */
    if (WAVE_Format.NumChannels == Channel_MONO)
    {
      /* Increment the monovar variable */
      monovar++;
    }

    /* Return the read value */
    return tmpvar;
  }
  /* Right channel to be sent in mono format */
  else
  {
    /* Reset the monovar variable */
    monovar = 0;

    /* Return the previous read data in mono format */
    return tmpvar;
  }
}

/*******************************************************************************
* Function Name  : I2S_CODEC_MediaReadByte
* Description    : Read one byte from the media (SPI_Flash/NOR/NAND memories..)
* Input          : - Offset: the address offset for read operation
* Output         : None.
* Return         : Data read from the media memory.
*******************************************************************************/
uint8_t Media_ReadByte(uint32_t Offset)
{
  uint8_t tmp = 0;

  /* Enable the FSMC that share a pin w/ I2C1 (LBAR) */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, ENABLE);

  /* Read data from the specified location */
  tmp =  (*(__IO uint8_t *) (AudioFileAddress + Offset));

  /* Disable the FSMC that share a pin w/ I2C1 (LBAR) */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, DISABLE);

  return tmp;
}

/*******************************************************************************
* Function Name  : Media_Init
* Description    : Read one byte from the media (SPI_Flash/NOR/NAND memories..)
* Input          : - Offset: the address offset for read operation
* Output         : None.
* Return         : - 0 if initialization is OK
*                  - 1 if initialization failed..
*******************************************************************************/
uint32_t Media_Init(void)
{
  return 0;
}

/*******************************************************************************
* Function Name  : Media_BufferRead
* Description    : Read a buffer from the memory media
* Input          : - pBuffer: Destination buffer address
*                : - ReadAddr: start reading position
*                : - NumByteToRead: size of the buffer to read
* Output         : None.
* Return         : None.
*******************************************************************************/
void Media_BufferRead(uint8_t* pBuffer, uint32_t ReadAddr, uint16_t NumByteToRead)
{
  /* Enable the FSMC that share a pin w/ I2C1 (LBAR) */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, ENABLE);

  /* Read the data */
  while (NumByteToRead--)
  {
    *pBuffer++ = *(__IO uint8_t *)ReadAddr++;
  }

  /* Disable the FSMC that share a pin w/ I2C1 (LBAR) */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_FSMC, DISABLE);
}

/*******************************************************************************
* Function Name  : Media_StartReadSequence
* Description    : Initialize reading sequence on the media.
* Input          : - ReadAddr: start reading position
* Output         : None.
* Return         : None.
*******************************************************************************/
void Media_StartReadSequence(uint32_t ReadAddr)
{
  /* This function could be used for memories needing a start read sequence
      like SPI_Flash memory */
}

/*******************************************************************************
* Function Name  : I2S_CODEC_DataTransfer
* Description    : Sends the audio data using the SPI2 peripheral and checks the
*                :   audio playing status (if a command (Pause/Stop) is pending
*                :   the playing status is updated). If the TXE flag interrupt
*                :   is used to synchronize data sending, this function should be
*                :   called in the SPI2 ISR.
* Input          : None.
* Output         : None.
* Return         : None.
*******************************************************************************/
void I2S_CODEC_DataTransfer(void)
{
  /* Audio codec configuration section -------------------------------------*/
  if (GetVar_SendDummyData() == 1)
  {
    /* Send a dummy data just to generate the I2S clock */
    SPI_I2S_SendData(SPI2, DUMMY_DATA);
  }
  /* Audio codec communication section -------------------------------------*/
  else
  {
    /* Send the data read from the memory */
    SPI_I2S_SendData(SPI2, (Media_ReadHalfWord(AudioDataIndex)));

    /* Increment the index */
    IncrementVar_AudioDataIndex(WAVE_Format.NumChannels);

    /* Check and update the stream playing status */
    I2S_CODEC_UpdateStatus();
  }
}
/*******************************************************************************
* Function Name  : delay
* Description    : Inserts a delay time.
* Input          : nCount: specifies the delay time length
* Output         : None
* Return         : The length of the wave file read from the SPI_Flash
*******************************************************************************/
void delay(__IO uint32_t nCount)
{
  for (; nCount != 0; nCount--);
}
#endif
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/