talkthrough.c

audio talktrough code. platform bf533 + audio card.

/*********************************************************************************

Copyright(c) 2005 Analog Devices, Inc. All Rights Reserved.

This software is proprietary and confidential.  By using this software you agree
to the terms of the associated Analog Devices License Agreement.

*********************************************************************************/
/*************************************************************************************

Description:    Supports conversion of non-interleaved per channel data array 
                from/to SPORT DMA data frame. The processData() function copies the
                processed output data from the Audio Handling function into DAC's buffer.
                It also copies ADC's input audio data into the working memory buffer 
                that acts as the Audio Handling function's input buffer   
                The Audio Handling is invoked through the separate
                interrupt thread for the function, or directly called by processData,
                depending on the SEPARATE_THREAD_FOR_RENDER definition.

*********************************************************************************/

/*********************************************************************

Include files

*********************************************************************/
#include <services\services.h>
#include <drivers\adi_dev.h>
#include "AudioDriver.h"
#if (SEPARATE_THREAD_FOR_RENDER)
#include <signal.h>
#endif

/*********************************************************************

Prototypes

*********************************************************************/

// external render function prototype
extern void DoProcessing(u32 *);

// flag for which buffer is being processed
static int bWhichBuffer = 1;    // 1 : first buffer, 0 : second buffer


/*********************************************************************

    Function:       FWRender
    
    Description:    This is the user interrupt service routine which 
                    runs on user interrupt 0.  It simply calls the glue function
                    for the DSP to handle input data.

*********************************************************************/
#if (SEPARATE_THREAD_FOR_RENDER)

// user interrupt 0 ISR
ADI_INT_HANDLER(FWRender)
{
    // do standalone DSP processing
    DoProcessing((u32*)ProcessingBuffer);

    return (ADI_INT_RESULT_PROCESSED);
}

#endif

/*********************************************************************

    Function:       processData
    
    Description:    Called by the audio driver ISR.  Copies the processed output 
                    data into the DMA transmit buffer and copies the input data 
                    from the DMA receive buffer into the same processing buffer.
                    Then it invokes user interrupt ISR or directly
                    calls a render function to handle the input data.
                    Double buffering scheme is used for DMA buffers.
    
*********************************************************************/

static void processData(void)
{
    int i, j;
    int **pOutputPtr, **pInputPtr;
    int *pSrc, *pDst;
    
    // switch ping pong variable for double buffering
    if (bWhichBuffer)       // indicating first portion is transferred
    {
        // toggle buffer flag
        bWhichBuffer = 0;
        
        // store local pointer for the first DMA buffer
        pOutputPtr = &pOutputSampleBasePtr[0];
        pInputPtr = &pInputSampleBasePtr[0];
    }
    else                    // indicating second portion is transferred
    {
        // toggle buffer flag
        bWhichBuffer = 1;

        // store local pointer for the second DMA buffer
        pOutputPtr = &pOutputSampleBasePtr[VALID_OUTPUT_CHANNEL_SIZE];
        pInputPtr = &pInputSampleBasePtr[VALID_INPUT_CHANNEL_SIZE];
    }
 
    //===========================================================================
    // write output buffer
    
    // convert array of valid output channels into TX DMA frame formatted data
    for (i = 0, pSrc = (int*)ProcessingBuffer; i < VALID_OUTPUT_CHANNEL_SIZE; i++)
    {
        for (j = 0; j < TDM_FRAME_SIZE * TICK_SAMPLE_SIZE; j += TDM_FRAME_SIZE)
            pOutputPtr[i][j] = *pSrc++;
    }


    //===========================================================================
    // handle input buffer
    
    // convert RX DMA frame formatted data into sequential array for each valid input channel
    for (i = 0, pDst = (int*)ProcessingBuffer; i < VALID_INPUT_CHANNEL_SIZE; i++)
    {
        for (j = 0; j < TDM_FRAME_SIZE * TICK_SAMPLE_SIZE; j += TDM_FRAME_SIZE)
            *pDst++ = pInputPtr[i][j];
    }
    
#if (SEPARATE_THREAD_FOR_RENDER)

    // call other interrupt for rendering
    raise(USER_ISR0);

#else

    // do standalone DSP processing
    DoProcessing((AMF_Signal*)ProcessingBuffer);

#endif
}

/*********************************************************************

    Function:       TalkthroughCallback
    
    Description:    Each type of callback event has it's own unique ID
                    so we can use a single callback function for all
                    callback events.  The switch statement tells us
                    which event has occurred.
                    
                    Note that in the device driver model, in order to 
                    generate a callback for buffer completion, the 
                    CallbackType of the buffer must be set to a flag 
                    indicating which pointer it will generate an interrupt
                    (each sub buffer (2D) or at the end of full buffer).
                    In this example, 2D is used for DMA transfer and we
                    need sub buffer callback type to do double buffering.
                    
*********************************************************************/

void TalkthroughCallback(void* AppHandle, u32 Event, void* pArg)
{
    switch (Event)
    {
        // CASE (DMA buffer processed)
        case ADI_DEV_EVENT_BUFFER_PROCESSED:
        break;
        case ADI_DEV_EVENT_SUB_BUFFER_PROCESSED:
        processData();
        break;
        
        case ADI_DEV_EVENT_DMA_ERROR_INTERRUPT:
        printf("DMA error interrupt\n");
        break;
	}
}