1: /*
    2:  * QEMU Timer based audio emulation
    3:  *
    4:  * Copyright (c) 2004-2005 Vassili Karpov (malc)
    5:  *
    6:  * Permission is hereby granted, free of charge, to any person obtaining a copy
    7:  * of this software and associated documentation files (the "Software"), to deal
    8:  * in the Software without restriction, including without limitation the rights
    9:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   10:  * copies of the Software, and to permit persons to whom the Software is
   11:  * furnished to do so, subject to the following conditions:
   12:  *
   13:  * The above copyright notice and this permission notice shall be included in
   14:  * all copies or substantial portions of the Software.
   15:  *
   16:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   17:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   18:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
   19:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   20:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   21:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   22:  * THE SOFTWARE.
   23:  */
   24: #include "qemu-common.h"
   25: #include "audio.h"
   26: #include "qemu-timer.h"
   27: 
   28: #define AUDIO_CAP "noaudio"
   29: #include "audio_int.h"
   30: 
   31: typedef struct NoVoiceOut {
   32:     HWVoiceOut hw;
   33:     int64_t old_ticks;
   34: } NoVoiceOut;
   35: 
   36: typedef struct NoVoiceIn {
   37:     HWVoiceIn hw;
   38:     int64_t old_ticks;
   39: } NoVoiceIn;
   40: 
   41: static int no_run_out (HWVoiceOut *hw)
   42: {
   43:     NoVoiceOut *no = (NoVoiceOut *) hw;
   44:     int live, decr, samples;
   45:     int64_t now;
   46:     int64_t ticks;
   47:     int64_t bytes;
   48: 
   49:     live = audio_pcm_hw_get_live_out (&no->hw);
   50:     if (!live) {
   51:         return 0;
   52:     }
   53: 
   54:     now = qemu_get_clock (vm_clock);
   55:     ticks = now - no->old_ticks;
   56:     bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
   57:     bytes = audio_MIN (bytes, INT_MAX);
   58:     samples = bytes >> hw->info.shift;
   59: 
   60:     no->old_ticks = now;
   61:     decr = audio_MIN (live, samples);
   62:     hw->rpos = (hw->rpos + decr) % hw->samples;
   63:     return decr;
   64: }
   65: 
   66: static int no_write (SWVoiceOut *sw, void *buf, int len)
   67: {
   68:     return audio_pcm_sw_write (sw, buf, len);
   69: }
   70: 
   71: static int no_init_out (HWVoiceOut *hw, audsettings_t *as)
   72: {
   73:     audio_pcm_init_info (&hw->info, as);
   74:     hw->samples = 1024;
   75:     return 0;
   76: }
   77: 
   78: static void no_fini_out (HWVoiceOut *hw)
   79: {
   80:     (void) hw;
   81: }
   82: 
   83: static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
   84: {
   85:     (void) hw;
   86:     (void) cmd;
   87:     return 0;
   88: }
   89: 
   90: static int no_init_in (HWVoiceIn *hw, audsettings_t *as)
   91: {
   92:     audio_pcm_init_info (&hw->info, as);
   93:     hw->samples = 1024;
   94:     return 0;
   95: }
   96: 
   97: static void no_fini_in (HWVoiceIn *hw)
   98: {
   99:     (void) hw;
  100: }
  101: 
  102: static int no_run_in (HWVoiceIn *hw)
  103: {
  104:     NoVoiceIn *no = (NoVoiceIn *) hw;
  105:     int live = audio_pcm_hw_get_live_in (hw);
  106:     int dead = hw->samples - live;
  107:     int samples = 0;
  108: 
  109:     if (dead) {
  110:         int64_t now = qemu_get_clock (vm_clock);
  111:         int64_t ticks = now - no->old_ticks;
  112:         int64_t bytes = (ticks * hw->info.bytes_per_second) / ticks_per_sec;
  113: 
  114:         no->old_ticks = now;
  115:         bytes = audio_MIN (bytes, INT_MAX);
  116:         samples = bytes >> hw->info.shift;
  117:         samples = audio_MIN (samples, dead);
  118:     }
  119:     return samples;
  120: }
  121: 
  122: static int no_read (SWVoiceIn *sw, void *buf, int size)
  123: {
  124:     int samples = size >> sw->info.shift;
  125:     int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired;
  126:     int to_clear = audio_MIN (samples, total);
  127:     audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
  128:     return to_clear;
  129: }
  130: 
  131: static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
  132: {
  133:     (void) hw;
  134:     (void) cmd;
  135:     return 0;
  136: }
  137: 
  138: static void *no_audio_init (void)
  139: {
  140:     return &no_audio_init;
  141: }
  142: 
  143: static void no_audio_fini (void *opaque)
  144: {
  145:     (void) opaque;
  146: }
  147: 
  148: static struct audio_pcm_ops no_pcm_ops = {
  149:     no_init_out,
  150:     no_fini_out,
  151:     no_run_out,
  152:     no_write,
  153:     no_ctl_out,
  154: 
  155:     no_init_in,
  156:     no_fini_in,
  157:     no_run_in,
  158:     no_read,
  159:     no_ctl_in
  160: };
  161: 
  162: struct audio_driver no_audio_driver = {
  163:     INIT_FIELD (name           = ) "none",
  164:     INIT_FIELD (descr          = ) "Timer based audio emulation",
  165:     INIT_FIELD (options        = ) NULL,
  166:     INIT_FIELD (init           = ) no_audio_init,
  167:     INIT_FIELD (fini           = ) no_audio_fini,
  168:     INIT_FIELD (pcm_ops        = ) &no_pcm_ops,
  169:     INIT_FIELD (can_be_default = ) 1,
  170:     INIT_FIELD (max_voices_out = ) INT_MAX,
  171:     INIT_FIELD (max_voices_in  = ) INT_MAX,
  172:     INIT_FIELD (voice_size_out = ) sizeof (NoVoiceOut),
  173:     INIT_FIELD (voice_size_in  = ) sizeof (NoVoiceIn)
  174: };