audio/noaudio.c

   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
  25 #include "qemu/osdep.h"
  26 #include "qemu/host-utils.h"
  27 #include "qemu/module.h"
  28 #include "audio.h"
  29 #include "qemu/timer.h"
  30
  31 #define AUDIO_CAP "noaudio"
  32 #include "audio_int.h"
  33
  34 typedef struct NoVoiceOut {
  35     HWVoiceOut hw;
  36     int64_t old_ticks;
  37 } NoVoiceOut;
  38
  39 typedef struct NoVoiceIn {
  40     HWVoiceIn hw;
  41     int64_t old_ticks;
  42 } NoVoiceIn;
  43
  44 static int no_run_out (HWVoiceOut *hw, int live)
  45 {
  46     NoVoiceOut *no = (NoVoiceOut *) hw;
  47     int decr, samples;
  48     int64_t now;
  49     int64_t ticks;
  50     int64_t bytes;
  51
  52     now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
  53     ticks = now - no->old_ticks;
  54     bytes = muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND);
  55     bytes = MIN(bytes, INT_MAX);
  56     samples = bytes >> hw->info.shift;
  57
  58     no->old_ticks = now;
  59     decr = MIN (live, samples);
  60     hw->rpos = (hw->rpos + decr) % hw->samples;
  61     return decr;
  62 }
  63
  64 static int no_write (SWVoiceOut *sw, void *buf, int len)
  65 {
  66     return audio_pcm_sw_write(sw, buf, len);
  67 }
  68
  69 static int no_init_out(HWVoiceOut *hw, struct audsettings *as, void *drv_opaque)
  70 {
  71     audio_pcm_init_info (&hw->info, as);
  72     hw->samples = 1024;
  73     return 0;
  74 }
  75
  76 static void no_fini_out (HWVoiceOut *hw)
  77 {
  78     (void) hw;
  79 }
  80
  81 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
  82 {
  83     (void) hw;
  84     (void) cmd;
  85     return 0;
  86 }
  87
  88 static int no_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
  89 {
  90     audio_pcm_init_info (&hw->info, as);
  91     hw->samples = 1024;
  92     return 0;
  93 }
  94
  95 static void no_fini_in (HWVoiceIn *hw)
  96 {
  97     (void) hw;
  98 }
  99
 100 static int no_run_in (HWVoiceIn *hw)
 101 {
 102     NoVoiceIn *no = (NoVoiceIn *) hw;
 103     int live = audio_pcm_hw_get_live_in (hw);
 104     int dead = hw->samples - live;
 105     int samples = 0;
 106
 107     if (dead) {
 108         int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 109         int64_t ticks = now - no->old_ticks;
 110         int64_t bytes =
 111             muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND);
 112
 113         no->old_ticks = now;
 114         bytes = MIN (bytes, INT_MAX);
 115         samples = bytes >> hw->info.shift;
 116         samples = MIN (samples, dead);
 117     }
 118     return samples;
 119 }
 120
 121 static int no_read (SWVoiceIn *sw, void *buf, int size)
 122 {
 123     /* use custom code here instead of audio_pcm_sw_read() to avoid
 124      * useless resampling/mixing */
 125     int samples = size >> sw->info.shift;
 126     int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired;
 127     int to_clear = MIN (samples, total);
 128     sw->total_hw_samples_acquired += total;
 129     audio_pcm_info_clear_buf (&sw->info, buf, to_clear);
 130     return to_clear << sw->info.shift;
 131 }
 132
 133 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
 134 {
 135     (void) hw;
 136     (void) cmd;
 137     return 0;
 138 }
 139
 140 static void *no_audio_init(Audiodev *dev)
 141 {
 142     return &no_audio_init;
 143 }
 144
 145 static void no_audio_fini (void *opaque)
 146 {
 147     (void) opaque;
 148 }
 149
 150 static struct audio_pcm_ops no_pcm_ops = {
 151     .init_out = no_init_out,
 152     .fini_out = no_fini_out,
 153     .run_out  = no_run_out,
 154     .write    = no_write,
 155     .ctl_out  = no_ctl_out,
 156
 157     .init_in  = no_init_in,
 158     .fini_in  = no_fini_in,
 159     .run_in   = no_run_in,
 160     .read     = no_read,
 161     .ctl_in   = no_ctl_in
 162 };
 163
 164 static struct audio_driver no_audio_driver = {
 165     .name           = "none",
 166     .descr          = "Timer based audio emulation",
 167     .init           = no_audio_init,
 168     .fini           = no_audio_fini,
 169     .pcm_ops        = &no_pcm_ops,
 170     .can_be_default = 1,
 171     .max_voices_out = INT_MAX,
 172     .max_voices_in  = INT_MAX,
 173     .voice_size_out = sizeof (NoVoiceOut),
 174     .voice_size_in  = sizeof (NoVoiceIn)
 175 };
 176
 177 static void register_audio_none(void)
 178 {
 179     audio_driver_register(&no_audio_driver);
 180 }
 181 type_init(register_audio_none);