apps/plugins/pdbox/PDa/src/s_audio_rockbox.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2009 Wincent Balin
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "plugin.h"
  23 #include "../../pdbox.h"
  24
  25 #include "m_pd.h"
  26 #include "s_stuff.h"
  27
  28 /* Extern variables. */
  29 extern float sys_dacsr;
  30 extern t_sample *sys_soundout;
  31 extern t_sample *sys_soundin;
  32
  33 /* Output buffer. */
  34 #define OUTBUFSIZE 3
  35 static struct audio_buffer outbuf[OUTBUFSIZE];
  36 static unsigned int outbuf_head;
  37 static unsigned int outbuf_tail;
  38 static unsigned int outbuf_fill;
  39
  40 /* Playing status. */
  41 static bool playing;
  42
  43
  44 /* Open audio. */
  45 void rockbox_open_audio(int rate)
  46 {
  47     unsigned int i;
  48
  49     /* No sound yet. */
  50     playing = false;
  51
  52     /* Stop playing to reconfigure audio settings. */
  53     rb->pcm_play_stop();
  54
  55 #if INPUT_SRC_CAPS != 0
  56     /* Select playback */
  57     rb->audio_set_input_source(AUDIO_SRC_PLAYBACK, SRCF_PLAYBACK);
  58     rb->audio_set_output_source(AUDIO_SRC_PLAYBACK);
  59 #endif
  60
  61     /* Set sample rate of the audio buffer. */
  62     rb->pcm_set_frequency(rate);
  63     rb->pcm_apply_settings();
  64
  65     /* Initialize output buffer. */
  66     for(i = 0; i < OUTBUFSIZE; i++)
  67         outbuf[i].fill = 0;
  68
  69     outbuf_head = 0;
  70     outbuf_tail = 0;
  71     outbuf_fill = 0;
  72 }
  73
  74 /* Close audio. */
  75 void rockbox_close_audio(void)
  76 {
  77     /* Stop playback. */
  78     rb->pcm_play_stop();
  79
  80     /* Reset playing status. */
  81     playing = false;
  82
  83     /* Restore default sampling rate. */
  84     rb->pcm_set_frequency(HW_SAMPR_DEFAULT);
  85     rb->pcm_apply_settings();
  86 }
  87
  88 /* Rockbox audio callback. */
  89 void pdbox_get_more(unsigned char** start, size_t* size)
  90 {
  91     if(outbuf_fill > 0)
  92     {
  93         /* Store output data address and size. */
  94         *start = (unsigned char*) outbuf[outbuf_tail].data;
  95         *size = sizeof(outbuf[outbuf_tail].data);
  96
  97         /* Free this part of output buffer. */
  98         outbuf[outbuf_tail].fill = 0;
  99
 100         /* Advance to the next part of output buffer. */
 101         if(outbuf_tail == OUTBUFSIZE-1)
 102             outbuf_tail = 0;
 103         else
 104             outbuf_tail++;
 105
 106         /* Decrease output buffer fill. */
 107         outbuf_fill--;
 108     }
 109     else
 110     {
 111         /* Reset playing status. */
 112         playing = false;
 113
 114         /* Nothing to play. */
 115         *start = NULL;
 116         *size = 0;
 117     }
 118 }
 119
 120 /* Audio I/O. */
 121 int rockbox_send_dacs(void)
 122 {
 123     /* Copy sys_output buffer. */
 124     t_sample* left = sys_soundout + DEFDACBLKSIZE*0;
 125     t_sample* right = sys_soundout + DEFDACBLKSIZE*1;
 126     unsigned int samples_out = 0;
 127     int16_t* out;
 128     int sample;
 129
 130     /* Cancel if whole buffer filled. */
 131     if(outbuf_fill >= OUTBUFSIZE-1)
 132         return SENDDACS_NO;
 133
 134     /* Write the block of sound. */
 135 write_block:
 136     for(out = outbuf[outbuf_head].data +
 137               outbuf[outbuf_head].fill * PD_OUT_CHANNELS;
 138         outbuf[outbuf_head].fill < (AUDIOBUFSIZE / PD_OUT_CHANNELS) &&
 139             samples_out < DEFDACBLKSIZE;
 140         left++, right++, samples_out++, outbuf[outbuf_head].fill++)
 141     {
 142         /* Copy samples from both channels. */
 143         sample = SCALE16(*left);
 144         if(sample > 32767)
 145             sample = 32767;
 146         else if(sample < -32767)
 147             sample = -32767;
 148         *out++ = sample;
 149         sample = SCALE16(*right);
 150         if(sample > 32767)
 151             sample = 32767;
 152         else if(sample < -32767)
 153             sample = -32767;
 154         *out++ = sample;
 155     }
 156
 157     /* If part of output buffer filled... */
 158     if(outbuf[outbuf_head].fill >= (AUDIOBUFSIZE / PD_OUT_CHANNELS))
 159     {
 160         /* Advance one part of output buffer. */
 161         if(outbuf_head == OUTBUFSIZE-1)
 162             outbuf_head = 0;
 163         else
 164             outbuf_head++;
 165
 166         /* Increase fill counter. */
 167         outbuf_fill++;
 168     }
 169
 170     /* If needed, fill the next frame. */
 171     if(samples_out < DEFDACBLKSIZE)
 172         goto write_block;
 173
 174     /* Clear Pure Data output buffer. */
 175     memset(sys_soundout,
 176            0,
 177            sizeof(t_sample) * DEFDACBLKSIZE * PD_OUT_CHANNELS);
 178
 179     /* If still not playing... */
 180     if(!playing && outbuf_fill > 0)
 181     {
 182         /* Start playing. */
 183         rb->pcm_play_data(pdbox_get_more, NULL, 0);
 184
 185         /* Set status flag. */
 186         playing = true;
 187     }
 188
 189     return SENDDACS_YES;
 190 }
 191