diff options
Diffstat (limited to 'distrib/sdl-1.2.15/src/audio/mint/SDL_mintaudio.c')
| -rw-r--r-- | distrib/sdl-1.2.15/src/audio/mint/SDL_mintaudio.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/audio/mint/SDL_mintaudio.c b/distrib/sdl-1.2.15/src/audio/mint/SDL_mintaudio.c new file mode 100644 index 0000000..46ba690 --- /dev/null +++ b/distrib/sdl-1.2.15/src/audio/mint/SDL_mintaudio.c @@ -0,0 +1,215 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2012 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 +*/ +#include "SDL_config.h" + +/* + Audio interrupt variables and callback function + + Patrice Mandin +*/ + +#include <unistd.h> + +#include <mint/osbind.h> +#include <mint/falcon.h> +#include <mint/mintbind.h> +#include <mint/cookie.h> + +#include "SDL_audio.h" +#include "SDL_mintaudio.h" +#include "SDL_mintaudio_stfa.h" + +/* The audio device */ + +SDL_AudioDevice *SDL_MintAudio_device; +Uint8 *SDL_MintAudio_audiobuf[2]; /* Pointers to buffers */ +unsigned long SDL_MintAudio_audiosize; /* Length of audio buffer=spec->size */ +volatile unsigned short SDL_MintAudio_numbuf; /* Buffer to play */ +volatile unsigned short SDL_MintAudio_mutex; +volatile unsigned long SDL_MintAudio_clocktics; +cookie_stfa_t *SDL_MintAudio_stfa; +unsigned short SDL_MintAudio_hasfpu; + +/* MiNT thread variables */ +SDL_bool SDL_MintAudio_mint_present; +SDL_bool SDL_MintAudio_quit_thread; +SDL_bool SDL_MintAudio_thread_finished; +long SDL_MintAudio_thread_pid; + +/* The callback function, called by each driver whenever needed */ + +void SDL_MintAudio_Callback(void) +{ + Uint8 *buffer; + SDL_AudioDevice *audio = SDL_MintAudio_device; + + buffer = SDL_MintAudio_audiobuf[SDL_MintAudio_numbuf]; + SDL_memset(buffer, audio->spec.silence, audio->spec.size); + + if (audio->paused) + return; + + if (audio->convert.needed) { + int silence; + + if ( audio->convert.src_format == AUDIO_U8 ) { + silence = 0x80; + } else { + silence = 0; + } + SDL_memset(audio->convert.buf, silence, audio->convert.len); + audio->spec.callback(audio->spec.userdata, + (Uint8 *)audio->convert.buf,audio->convert.len); + SDL_ConvertAudio(&audio->convert); + SDL_memcpy(buffer, audio->convert.buf, audio->convert.len_cvt); + } else { + audio->spec.callback(audio->spec.userdata, buffer, audio->spec.size); + } +} + +/* Add a new frequency/clock/predivisor to the current list */ +void SDL_MintAudio_AddFrequency(_THIS, Uint32 frequency, Uint32 clock, + Uint32 prediv, int gpio_bits) +{ + int i, p; + + if (MINTAUDIO_freqcount==MINTAUDIO_maxfreqs) { + return; + } + + /* Search where to insert the frequency (highest first) */ + for (p=0; p<MINTAUDIO_freqcount; p++) { + if (frequency > MINTAUDIO_frequencies[p].frequency) { + break; + } + } + + /* Put all following ones farer */ + if (MINTAUDIO_freqcount>0) { + for (i=MINTAUDIO_freqcount; i>p; i--) { + SDL_memcpy(&MINTAUDIO_frequencies[i], &MINTAUDIO_frequencies[i-1], sizeof(mint_frequency_t)); + } + } + + /* And insert new one */ + MINTAUDIO_frequencies[p].frequency = frequency; + MINTAUDIO_frequencies[p].masterclock = clock; + MINTAUDIO_frequencies[p].predivisor = prediv; + MINTAUDIO_frequencies[p].gpio_bits = gpio_bits; + + MINTAUDIO_freqcount++; +} + +/* Search for the nearest frequency */ +int SDL_MintAudio_SearchFrequency(_THIS, int desired_freq) +{ + int i; + + /* Only 1 freq ? */ + if (MINTAUDIO_freqcount==1) { + return 0; + } + + /* Check the array */ + for (i=0; i<MINTAUDIO_freqcount; i++) { + if (desired_freq >= ((MINTAUDIO_frequencies[i].frequency+ + MINTAUDIO_frequencies[i+1].frequency)>>1)) { + return i; + } + } + + /* Not in the array, give the latest */ + return MINTAUDIO_freqcount-1; +} + +/* Check if FPU is present */ +void SDL_MintAudio_CheckFpu(void) +{ + long cookie_fpu; + + SDL_MintAudio_hasfpu = 0; + if (Getcookie(C__FPU, &cookie_fpu) != C_FOUND) { + return; + } + switch ((cookie_fpu>>16)&0xfffe) { + case 2: + case 4: + case 6: + case 8: + case 16: + SDL_MintAudio_hasfpu = 1; + break; + } +} + +/* The thread function, used under MiNT with xbios */ +int SDL_MintAudio_Thread(long param) +{ + SndBufPtr pointers; + SDL_bool buffers_filled[2] = {SDL_FALSE, SDL_FALSE}; + + SDL_MintAudio_thread_finished = SDL_FALSE; + while (!SDL_MintAudio_quit_thread) { + if (Buffptr(&pointers)!=0) + continue; + + if (( (unsigned long)pointers.play>=(unsigned long)SDL_MintAudio_audiobuf[0]) + && ( (unsigned long)pointers.play<=(unsigned long)SDL_MintAudio_audiobuf[1])) + { + /* DMA is reading buffer #0, setup buffer #1 if not already done */ + if (!buffers_filled[1]) { + SDL_MintAudio_numbuf = 1; + SDL_MintAudio_Callback(); + Setbuffer(0, SDL_MintAudio_audiobuf[1], SDL_MintAudio_audiobuf[1] + SDL_MintAudio_audiosize); + buffers_filled[1]=SDL_TRUE; + buffers_filled[0]=SDL_FALSE; + } + } else { + /* DMA is reading buffer #1, setup buffer #0 if not already done */ + if (!buffers_filled[0]) { + SDL_MintAudio_numbuf = 0; + SDL_MintAudio_Callback(); + Setbuffer(0, SDL_MintAudio_audiobuf[0], SDL_MintAudio_audiobuf[0] + SDL_MintAudio_audiosize); + buffers_filled[0]=SDL_TRUE; + buffers_filled[1]=SDL_FALSE; + } + } + + usleep(100); + } + SDL_MintAudio_thread_finished = SDL_TRUE; + return 0; +} + +void SDL_MintAudio_WaitThread(void) +{ + if (!SDL_MintAudio_mint_present) + return; + + if (SDL_MintAudio_thread_finished) + return; + + SDL_MintAudio_quit_thread = SDL_TRUE; + while (!SDL_MintAudio_thread_finished) { + Syield(); + } +} |