/*

SDL - Simple DirectMedia Layer

Copyright (C) 1997-2004 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Library General Public

License as published by the Free Software Foundation; either

version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Library General Public License for more details.

You should have received a copy of the GNU Library General Public

License along with this library; if not, write to the Free

Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

Sam Lantinga

slouken@libsdl.org

*/

/*

MiNT audio driver

using XBIOS functions (STFA driver)

Patrice Mandin

*/

/* Mint includes */

#include <mint/osbind.h>

#include <mint/falcon.h>

#include <mint/cookie.h>

#include "SDL_audio.h"

#include "SDL_audio_c.h"

#include "SDL_audiomem.h"

#include "SDL_sysaudio.h"

#include "SDL_atarimxalloc_c.h"

#include "SDL_mintaudio.h"

#include "SDL_mintaudio_stfa.h"

/*--- Defines ---*/

#define MINT_AUDIO_DRIVER_NAME "mint_stfa"

/* Debug print info */

#define DEBUG_NAME "audio:stfa: "

#if 0

#define DEBUG_PRINT(what) \

{ \

printf what; \

}

#else

#define DEBUG_PRINT(what)

#endif

/*--- Static variables ---*/

static unsigned long cookie_snd, cookie_mch;

static cookie_stfa_t *cookie_stfa;

static const int freqs[16]={

4995, 6269, 7493, 8192,

9830, 10971, 12538, 14985,

16384, 19819, 21943, 24576,

30720, 32336, 43885, 49152

};

/*--- Audio driver functions ---*/

static void Mint_CloseAudio(_THIS);

static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec);

static void Mint_LockAudio(_THIS);

static void Mint_UnlockAudio(_THIS);

/* To check/init hardware audio */

static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec);

static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec);

/*--- Audio driver bootstrap functions ---*/

static int Audio_Available(void)

{

const char *envr = SDL_getenv("SDL_AUDIODRIVER");

/* Check if user asked a different audio driver */

if ((envr) && (SDL_strcmp(envr, MINT_AUDIO_DRIVER_NAME)!=0)) {

DEBUG_PRINT((DEBUG_NAME "user asked a different audio driver\n"));

return(0);

}

/* Cookie _MCH present ? if not, assume ST machine */

if (Getcookie(C__MCH, &cookie_mch) == C_NOTFOUND) {

cookie_mch = MCH_ST;

}

/* Cookie _SND present ? if not, assume ST machine */

if (Getcookie(C__SND, &cookie_snd) == C_NOTFOUND) {

cookie_snd = SND_PSG;

}

/* Cookie STFA present ? */

if (Getcookie(C_STFA, (long *) &cookie_stfa) != C_FOUND) {

DEBUG_PRINT((DEBUG_NAME "no STFA audio\n"));

return(0);

}

SDL_MintAudio_stfa = cookie_stfa;

DEBUG_PRINT((DEBUG_NAME "STFA audio available!\n"));

return(1);

}

static void Audio_DeleteDevice(SDL_AudioDevice *device)

{

SDL_free(device->hidden);

SDL_free(device);

}

static SDL_AudioDevice *Audio_CreateDevice(int devindex)

{

SDL_AudioDevice *this;

/* Initialize all variables that we clean on shutdown */

this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));

if ( this ) {

SDL_memset(this, 0, (sizeof *this));

this->hidden = (struct SDL_PrivateAudioData *)

SDL_malloc((sizeof *this->hidden));

}

if ( (this == NULL) || (this->hidden == NULL) ) {

SDL_OutOfMemory();

if ( this ) {

SDL_free(this);

}

return(0);

}

SDL_memset(this->hidden, 0, (sizeof *this->hidden));

/* Set the function pointers */

this->OpenAudio = Mint_OpenAudio;

this->CloseAudio = Mint_CloseAudio;

this->LockAudio = Mint_LockAudio;

this->UnlockAudio = Mint_UnlockAudio;

this->free = Audio_DeleteDevice;

return this;

}

AudioBootStrap MINTAUDIO_STFA_bootstrap = {

MINT_AUDIO_DRIVER_NAME, "MiNT STFA audio driver",

Audio_Available, Audio_CreateDevice

};

static void Mint_LockAudio(_THIS)

{

void *oldpile;

/* Stop replay */

oldpile=(void *)Super(0);

cookie_stfa->sound_enable=STFA_PLAY_DISABLE;

Super(oldpile);

}

static void Mint_UnlockAudio(_THIS)

{

void *oldpile;

/* Restart replay */

oldpile=(void *)Super(0);

cookie_stfa->sound_enable=STFA_PLAY_ENABLE|STFA_PLAY_REPEAT;

Super(oldpile);

}

static void Mint_CloseAudio(_THIS)

{

void *oldpile;

/* Stop replay */

oldpile=(void *)Super(0);

cookie_stfa->sound_enable=STFA_PLAY_DISABLE;

Super(oldpile);

/* Wait if currently playing sound */

while (SDL_MintAudio_mutex != 0) {

}

/* Clear buffers */

if (SDL_MintAudio_audiobuf[0]) {

Mfree(SDL_MintAudio_audiobuf[0]);

SDL_MintAudio_audiobuf[0] = SDL_MintAudio_audiobuf[1] = NULL;

}

}

static int Mint_CheckAudio(_THIS, SDL_AudioSpec *spec)

{

int i;

DEBUG_PRINT((DEBUG_NAME "asked: %d bits, ",spec->format & 0x00ff));

DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));

DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x1000)!=0)));

DEBUG_PRINT(("channels=%d, ", spec->channels));

DEBUG_PRINT(("freq=%d\n", spec->freq));

/* Check formats available */

MINTAUDIO_freqcount=0;

for (i=0;i<16;i++) {

SDL_MintAudio_AddFrequency(this, freqs[i], 0, i, -1);

}

#if 1

for (i=0; i<MINTAUDIO_freqcount; i++) {

DEBUG_PRINT((DEBUG_NAME "freq %d: %lu Hz, clock %lu, prediv %d\n",

i, MINTAUDIO_frequencies[i].frequency, MINTAUDIO_frequencies[i].masterclock,

MINTAUDIO_frequencies[i].predivisor

));

}

#endif

MINTAUDIO_numfreq=SDL_MintAudio_SearchFrequency(this, spec->freq);

spec->freq=MINTAUDIO_frequencies[MINTAUDIO_numfreq].frequency;

DEBUG_PRINT((DEBUG_NAME "obtained: %d bits, ",spec->format & 0x00ff));

DEBUG_PRINT(("signed=%d, ", ((spec->format & 0x8000)!=0)));

DEBUG_PRINT(("big endian=%d, ", ((spec->format & 0x1000)!=0)));

DEBUG_PRINT(("channels=%d, ", spec->channels));

DEBUG_PRINT(("freq=%d\n", spec->freq));

return 0;

}

static void Mint_InitAudio(_THIS, SDL_AudioSpec *spec)

{

void *buffer;

void *oldpile;

buffer = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf];

oldpile=(void *)Super(0);

/* Stop replay */

cookie_stfa->sound_enable=STFA_PLAY_DISABLE;

/* Select replay format */

cookie_stfa->sound_control = MINTAUDIO_frequencies[MINTAUDIO_numfreq].predivisor;

if ((spec->format & 0xff)==8) {

cookie_stfa->sound_control |= STFA_FORMAT_8BIT;

} else {

cookie_stfa->sound_control |= STFA_FORMAT_16BIT;

}

if (spec->channels==2) {

cookie_stfa->sound_control |= STFA_FORMAT_STEREO;

} else {

cookie_stfa->sound_control |= STFA_FORMAT_MONO;

}

if ((spec->format & 0x8000)!=0) {

cookie_stfa->sound_control |= STFA_FORMAT_SIGNED;

} else {

cookie_stfa->sound_control |= STFA_FORMAT_UNSIGNED;

}

if ((spec->format & 0x1000)!=0) {

cookie_stfa->sound_control |= STFA_FORMAT_BIGENDIAN;

} else {

cookie_stfa->sound_control |= STFA_FORMAT_LITENDIAN;

}

/* Set buffer */

cookie_stfa->sound_start = (unsigned long) buffer;

cookie_stfa->sound_end = (unsigned long) (buffer + spec->size);

/* Set interrupt */

cookie_stfa->stfa_it = SDL_MintAudio_StfaInterrupt;

/* Restart replay */

cookie_stfa->sound_enable=STFA_PLAY_ENABLE|STFA_PLAY_REPEAT;

Super(oldpile);

DEBUG_PRINT((DEBUG_NAME "hardware initialized\n"));

}

static int Mint_OpenAudio(_THIS, SDL_AudioSpec *spec)

{

SDL_MintAudio_device = this;

/* Check audio capabilities */

if (Mint_CheckAudio(this, spec)==-1) {

return -1;

}

SDL_CalculateAudioSpec(spec);

/* Allocate memory for audio buffers in DMA-able RAM */

DEBUG_PRINT((DEBUG_NAME "buffer size=%d\n", spec->size));

SDL_MintAudio_audiobuf[0] = Atari_SysMalloc(spec->size *2, MX_STRAM);

if (SDL_MintAudio_audiobuf[0]==NULL) {

SDL_SetError("MINT_OpenAudio: Not enough memory for audio buffer");

return (-1);

}

SDL_MintAudio_audiobuf[1] = SDL_MintAudio_audiobuf[0] + spec->size ;

SDL_MintAudio_numbuf=0;

SDL_memset(SDL_MintAudio_audiobuf[0], spec->silence, spec->size *2);

SDL_MintAudio_audiosize = spec->size;

SDL_MintAudio_mutex = 0;

DEBUG_PRINT((DEBUG_NAME "buffer 0 at 0x%08x\n", SDL_MintAudio_audiobuf[0]));

DEBUG_PRINT((DEBUG_NAME "buffer 1 at 0x%08x\n", SDL_MintAudio_audiobuf[1]));

/* Setup audio hardware */

Mint_InitAudio(this, spec);

return(1); /* We don't use threaded audio */

}