usbd_audio_out_if.c

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/* Includes ------------------------------------------------------------------*/
#include "usbd_audio_core.h"
#include "usbd_audio_out_if.h"

static uint8_t  Init         (uint32_t  AudioFreq, uint32_t Volume, uint32_t options);
static uint8_t  DeInit       (uint32_t options);
static uint8_t  AudioCmd     (uint8_t* pbuf, uint32_t size, uint8_t cmd);
static uint8_t  VolumeCtl    (uint8_t vol);
static uint8_t  MuteCtl      (uint8_t cmd);
static uint8_t  PeriodicTC   (uint8_t cmd);
static uint8_t  GetState     (void);

AUDIO_FOPS_TypeDef  AUDIO_OUT_fops = 
{
  Init,
  DeInit,
  AudioCmd,
  VolumeCtl,
  MuteCtl,
  PeriodicTC,
  GetState
};

static uint8_t AudioState = AUDIO_STATE_INACTIVE;

static uint8_t  Init         (uint32_t AudioFreq, 
                              uint32_t Volume, 
                              uint32_t options)
{
  static uint32_t Initialized = 0;
  
  /* Check if the low layer has already been initialized */
  if (Initialized == 0)
  {
    /* Call low layer function */
    if (EVAL_AUDIO_Init(OUTPUT_DEVICE_AUTO, Volume, AudioFreq) != 0)
    {
      AudioState = AUDIO_STATE_ERROR;
      return AUDIO_FAIL;
    }
    
    /* Set the Initialization flag to prevent reinitializing the interface again */
    Initialized = 1;
  }
  
  /* Update the Audio state machine */
  AudioState = AUDIO_STATE_ACTIVE;
    
  return AUDIO_OK;
}

static uint8_t  DeInit       (uint32_t options)
{
  /* Update the Audio state machine */
  AudioState = AUDIO_STATE_INACTIVE;
  
  return AUDIO_OK;
}

static uint8_t  AudioCmd(uint8_t* pbuf, 
                         uint32_t size,
                         uint8_t cmd)
{
  /* Check the current state */
  if ((AudioState == AUDIO_STATE_INACTIVE) || (AudioState == AUDIO_STATE_ERROR))
  {
    AudioState = AUDIO_STATE_ERROR;
    return AUDIO_FAIL;
  }
  
  switch (cmd)
  {
    /* Process the PLAY command ----------------------------*/
  case AUDIO_CMD_PLAY:
    /* If current state is Active or Stopped */
    if ((AudioState == AUDIO_STATE_ACTIVE) || \
       (AudioState == AUDIO_STATE_STOPPED) || \
       (AudioState == AUDIO_STATE_PLAYING))
    {
      Audio_MAL_Play((uint32_t)pbuf, (size/2));
      AudioState = AUDIO_STATE_PLAYING;
      return AUDIO_OK;
    }
    /* If current state is Paused */
    else if (AudioState == AUDIO_STATE_PAUSED)
    {
      if (EVAL_AUDIO_PauseResume(AUDIO_RESUME, (uint32_t)pbuf, (size/2)) != 0)
      {
        AudioState = AUDIO_STATE_ERROR;
        return AUDIO_FAIL;
      }
      else
      {
        AudioState = AUDIO_STATE_PLAYING;
        return AUDIO_OK;
      } 
    } 
    else /* Not allowed command */
    {
      return AUDIO_FAIL;
    }
    
    /* Process the STOP command ----------------------------*/
  case AUDIO_CMD_STOP:
    if (AudioState != AUDIO_STATE_PLAYING)
    {
      /* Unsupported command */
      return AUDIO_FAIL;
    }
    else if (EVAL_AUDIO_Stop(CODEC_PDWN_SW) != 0)
    {
      AudioState = AUDIO_STATE_ERROR;
      return AUDIO_FAIL;
    }
    else
    {
      AudioState = AUDIO_STATE_STOPPED;
      return AUDIO_OK;
    }
  
    /* Process the PAUSE command ---------------------------*/
  case AUDIO_CMD_PAUSE:
    if (AudioState != AUDIO_STATE_PLAYING)
    {
      /* Unsupported command */
      return AUDIO_FAIL;
    }
    else if (EVAL_AUDIO_PauseResume(AUDIO_PAUSE, (uint32_t)pbuf, (size/2)) != 0)
    {
      AudioState = AUDIO_STATE_ERROR;
      return AUDIO_FAIL;
    }
    else
    {
      AudioState = AUDIO_STATE_PAUSED;
      return AUDIO_OK;
    } 
    
    /* Unsupported command ---------------------------------*/
  default:
    return AUDIO_FAIL;
  }  
}

static uint8_t  VolumeCtl    (uint8_t vol)
{
  /* Call low layer volume setting function */  
  if (EVAL_AUDIO_VolumeCtl(vol) != 0)
  {
    AudioState = AUDIO_STATE_ERROR;
    return AUDIO_FAIL;
  }
  
  return AUDIO_OK;
}

static uint8_t  MuteCtl      (uint8_t cmd)
{
  /* Call low layer mute setting function */  
  if (EVAL_AUDIO_Mute(cmd) != 0)
  {
    AudioState = AUDIO_STATE_ERROR;
    return AUDIO_FAIL;
  }
  
  return AUDIO_OK;
}

static uint8_t  PeriodicTC   (uint8_t cmd)
{

  
  return AUDIO_OK;
}


static uint8_t  GetState   (void)
{
  return AudioState;
}

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/