wm97audio.c

WM9713 audio codec driver for WinCE 5.0

 /*-----------------------------------------------------------------------------
 * Copyright (c) Wolfson Microelectronics plc.  All rights reserved.
 *
 * This software as well as any related documentation is furnished under 
 * license and may only be used or copied in accordance with the terms of the 
 * license. The information in this file is furnished for informational use 
 * only, is subject to change without notice, and should not be construed as 
 * a commitment by Wolfson Microelectronics plc. Wolfson Microelectronics plc
 * assumes no responsibility or liability for any errors or inaccuracies that
 * may appear in this document or any software that may be provided in
 * association with this document. 
 *
 * Except as permitted by such license, no part of this document may be 
 * reproduced, stored in a retrieval system, or transmitted in any form or by 
 * any means without the express written consent of Wolfson Microelectronics plc. 
 *
 * $Id: WM97Audio.c 2326 2005-10-20 08:40:38Z ib $
 *
 * This file contains platform-independent routines for controlling the audio
 * operation on Wolfson AC97 codecs.
 *
 * Warning:
 *  This driver is specifically written for Wolfson Codecs. It is not a 
 *  general CODEC device driver.
 *
 * -----------------------------------------------------------------------------*/

/*
 * Include files
 */
#include "WMCommon.h"
#include "WMDevice.h"
#include "WMControlLink.h"
#include "WMPower.h"
#include "WM9713Audio.h"
#include "WM97Audio.h"
/*
 * Only build this if we're doing Audio support.
 */
#if WM_AUDIO && WM_AC97

/*
 * Global definitions
 */

/*
 * Private data
 */
 


/*
 * Function prototypes
 */

/*-----------------------------------------------------------------------------
 * Function:    WM97SetSampleRate
 *
 * Called to Set the sample Rate in the audio-specific sections of the chip. 
 *
 * Parameters:
 *      hDevice      handle to the device (from WMOpenDevice)
 *      stream       The stream for which to set the sample rate
 *      sampleRate   The requested sample rate.
 *
 * Returns:     WMSTATUS
 *      See WMStatus.h.
 *---------------------------------------------------------------------------*/
WMSTATUS WM97SetSampleRate( WM_DEVICE_HANDLE hDevice,
                            WM_STREAM_ID     stream, 
                            WM_SAMPLE_RATE   sampleRate
                          )
{
    WMSTATUS            status;
    WM_REGTYPE          reg = 0;
    WM_POWERFLAG        powerState = 0;

#if WM_VOICE
    if ( WM_IS_VOICE_SUPPORTED( hDevice ) &&
            ( ( stream == WM_STREAM_VOICE_IN ) || ( stream == WM_STREAM_VOICE_OUT ) )
       )
    {
        /*
         * Set the Voice sample rate.
         */
        status = WM9713VoiceSetRate( hDevice, sampleRate );
    }
    else
#endif /* WM_VOICE */
    {
        /* Check which sample rate we need to set */
        switch (stream)
        {
            case WM_STREAM_HIFI_IN:
                reg = WM97_ADC_RATE;
            break;

            case WM_STREAM_HIFI_OUT:
                reg = WM97_DAC_RATE;
            break;

            case WM_STREAM_MONO_OUT:
                if ( WM_HAS_MONO_DAC( hDevice ) )
                {
                    reg = WM97_AUXDAC_RATE;
                }
                else
                {
                    status = WMS_UNSUPPORTED;
                    goto finish;
                }
                break;

            default :
                status = WMS_UNSUPPORTED;
                goto finish;
        }

        /* Check sample rate */
        switch ( sampleRate )
        {
            case WM_SAMPLE_RATE_8K:
            case WM_SAMPLE_RATE_11K025:
            case WM_SAMPLE_RATE_16K:
            case WM_SAMPLE_RATE_22K05:
            case WM_SAMPLE_RATE_32K:
            case WM_SAMPLE_RATE_44K1:
            case WM_SAMPLE_RATE_48K:
            {
                break;
            }

            case WM_SAMPLE_RATE_12K:
            case WM_SAMPLE_RATE_24K:
            {
                if ( !WM_HAS_EXTENDED_SAMPLE_RATES( hDevice ) )
                {
                    status = WMS_INVALID_PARAMETER;
                    goto finish;
                }
        
                break;
            }

            default:
            {
                status = WMS_INVALID_PARAMETER;
                goto finish;
            }
        }

        /* Set the VRA bit */
        status = WMSetField( hDevice,
                             WM97_AUDIO_CONTROL,
                             WM97_VRA_ENABLED,
                             WM97_VRA_ENABLED
                           );
        if ( WM_ERROR( status ) )
        {
            goto finish;
        }

        if ( stream == WM_STREAM_HIFI_IN )
        {
            /*
             * On the WM97XX we need to power up the ADC
             * at this point because if we try to write the sample rate 
             * with the ADC powered down the value in the register will
             * change but it will not be latched in to the device.
             */

            /*
             * Check the current power state of the ADC so that we can restore it
             * once we have finished.
             */
            powerState = WMGetCurrentPowerState( hDevice );

            if( ! ( WM_POWER_AUDIO_HIFI_ADC & powerState ) )
            {
                status = WMPowerUp( hDevice, WM_DRIVER_INTERNAL, WM_POWER_AUDIO_HIFI_ADC );
                if ( WM_ERROR( status ) )
                {
                    WM_TRACE( hDevice, (
                              "WM97SetSampleRate : WMAudioPowerUp failed: %s",
                              WMStatusText( status )
                            ));

                    goto finish;
                }
            }
        }

        /*
         * Write the sample rate.
         */
        status = WMWrite( hDevice, reg, sampleRate );


        if ( stream == WM_STREAM_HIFI_IN )
        {
            /*
             * Now that the ADC sample rate has been changed we can power the
             * ADC back down if it was powered down when we entered this function.
             */

            if( ! ( WM_POWER_AUDIO_HIFI_ADC & powerState ) )
            {
                /*
                 * Power down the ADC.
                 */
                status = WMPowerDown( hDevice, WM_DRIVER_INTERNAL, WM_POWER_AUDIO_HIFI_ADC );
                if ( WM_ERROR( status ) )
                {
                    WM_TRACE( hDevice, (
                              "WM97SetSampleRate : WMAudioPowerUp failed: %s",
                              WMStatusText( status )
                            ));

                    goto finish;
                }
            }
        }
    }

finish:
    return status;
}

/*-----------------------------------------------------------------------------
 * Function:    WM97GetSampleRate
 *
 * Returns the sample rate in the audio-specific sections of the chip. 
 *
 * Parameters:
 *      hDevice      handle to the device (from WMOpenDevice)
 *      stream       The stream for which to get the sample rate
 *      pSampleRate  Variable to receive the sample rate
 *
 * Returns:     WMSTATUS
 *       See WMStatus.h.
 *---------------------------------------------------------------------------*/
WMSTATUS WM97GetSampleRate( WM_DEVICE_HANDLE hDevice,
                            WM_STREAM_ID     stream, 
                            WM_SAMPLE_RATE   *pSampleRate
                          )
{
    WMSTATUS            status;
    WM_REGTYPE          reg;
    WM_REGVAL           sampleRate;

    /* Check which sample rate we need to query */
    switch ( stream )
    {
        case WM_STREAM_HIFI_IN:
            reg = WM97_ADC_RATE;
        break;

        case WM_STREAM_HIFI_OUT:
            reg = WM97_DAC_RATE;
        break;

        case WM_STREAM_MONO_OUT:
            if ( WM_HAS_MONO_DAC( hDevice ) )
            {
                reg = WM97_AUXDAC_RATE;
            }
            else
            {
                status = WMS_UNSUPPORTED;
                goto finish;
            }
            break;

        default :
            status = WMS_UNSUPPORTED;
            goto finish;
    }
    
    /*
     * Read the sample rate.
     */
    status = WMRead( hDevice, reg, &sampleRate );
    if ( WM_SUCCESS( status ) )
    {
        *pSampleRate = (WM_SAMPLE_RATE) sampleRate;
    }
    
    /*
     * And we're done.
     */
finish:
    return status;
}

#endif  /* WM_AUDIO && WM_AC97 */

/*------------------------------ END OF FILE ---------------------------------*/