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