2019-09-01 21:47:54 +01:00

136 lines
3.3 KiB
C

/*
* $Id: sgidrv.c 1.5 1996/08/05 18:51:19 chasan released $
*
* Silicon Graphics Indigo audio driver.
*
* Copyright (C) 1995-1999 Carlos Hasan
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <audio.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "audio.h"
#include "drivers.h"
/*
* SGI audio driver buffer size
*/
#define BUFFERSIZE 2048
/*
* SGI audio driver configuration structure
*/
static struct {
ALport Port;
ALconfig Config;
WORD wFormat;
BYTE aBuffer[BUFFERSIZE];
LPFNAUDIOWAVE lpfnAudioWave;
} Audio;
/*
* SGI audio driver API interface
*/
static UINT AIAPI GetAudioCaps(LPAUDIOCAPS lpCaps)
{
static AUDIOCAPS Caps =
{
AUDIO_PRODUCT_SGI, "Silicon Graphics",
AUDIO_FORMAT_1M08 | AUDIO_FORMAT_1S08 |
AUDIO_FORMAT_1M16 | AUDIO_FORMAT_1S16 |
AUDIO_FORMAT_2M08 | AUDIO_FORMAT_2S08 |
AUDIO_FORMAT_2M16 | AUDIO_FORMAT_2S16 |
AUDIO_FORMAT_4M08 | AUDIO_FORMAT_4S08 |
AUDIO_FORMAT_4M16 | AUDIO_FORMAT_4S16
};
memcpy(lpCaps, &Caps, sizeof(AUDIOCAPS));
return AUDIO_ERROR_NONE;
}
static UINT AIAPI PingAudio(VOID)
{
return AUDIO_ERROR_NONE;
}
static UINT AIAPI OpenAudio(LPAUDIOINFO lpInfo)
{
long op[2];
memset(&Audio, 0, sizeof(Audio));
if ((Audio.Config = ALnewconfig()) != NULL) {
/* setup encoding format for playback */
ALsetwidth(Audio.Config, lpInfo->wFormat & AUDIO_FORMAT_16BITS ?
AL_SAMPLE_16 : AL_SAMPLE_8);
ALsetchannels(Audio.Config, lpInfo->wFormat & AUDIO_FORMAT_STEREO ?
AL_STEREO : AL_MONO);
/* open audio port and configure it */
Audio.Port = ALopenport("Audio Port", "w", Audio.Config);
Audio.wFormat = lpInfo->wFormat;
/* setup playback sampling frequency */
if (Audio.Port != NULL) {
op[0] = AL_OUTPUT_RATE;
op[1] = lpInfo->nSampleRate;
ALsetparms(AL_DEFAULT_DEVICE, op, 2);
return AUDIO_ERROR_NONE;
}
}
return AUDIO_ERROR_DEVICEBUSY;
}
static UINT AIAPI CloseAudio(VOID)
{
while (ALgetfilled(Audio.Port) > 0)
sleep(1);
ALcloseport(Audio.Port);
ALfreeconfig(Audio.Config);
return AUDIO_ERROR_NONE;
}
static UINT AIAPI UpdateAudio(UINT nFrames)
{
if (Audio.wFormat & AUDIO_FORMAT_16BITS) nFrames <<= 1;
if (Audio.wFormat & AUDIO_FORMAT_STEREO) nFrames <<= 1;
if (nFrames <= 0 || nFrames >= sizeof(Audio.aBuffer))
nFrames = sizeof(Audio.aBuffer);
if (Audio.lpfnAudioWave != NULL) {
Audio.lpfnAudioWave(Audio.aBuffer, nFrames);
ALwritesamps(Audio.Port, Audio.aBuffer, nFrames >>
((Audio.wFormat & AUDIO_FORMAT_16BITS) != 0));
}
return AUDIO_ERROR_NONE;
}
static UINT AIAPI SetAudioCallback(LPFNAUDIOWAVE lpfnAudioWave)
{
Audio.lpfnAudioWave = lpfnAudioWave;
return AUDIO_ERROR_NONE;
}
/*
* SGI audio driver public interface
*/
AUDIOWAVEDRIVER SiliconWaveDriver =
{
GetAudioCaps, PingAudio, OpenAudio, CloseAudio,
UpdateAudio, SetAudioCallback
};
AUDIODRIVER SiliconDriver =
{
&SiliconWaveDriver, NULL
};