LXR qemu/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
  34typedef struct NoVoiceOut {
  35    HWVoiceOut hw;
  36    int64_t old_ticks;
  37} NoVoiceOut;
  38
  39typedef struct NoVoiceIn {
  40    HWVoiceIn hw;
  41    int64_t old_ticks;
  42} NoVoiceIn;
  43
  44static 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 = audio_MIN(bytes, INT_MAX);
  56    samples = bytes >> hw->info.shift;
  57
  58    no->old_ticks = now;
  59    decr = audio_MIN (live, samples);
  60    hw->rpos = (hw->rpos + decr) % hw->samples;
  61    return decr;
  62}
  63
  64static int no_write (SWVoiceOut *sw, void *buf, int len)
  65{
  66    return audio_pcm_sw_write(sw, buf, len);
  67}
  68
  69static 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
  76static void no_fini_out (HWVoiceOut *hw)
  77{
  78    (void) hw;
  79}
  80
  81static int no_ctl_out (HWVoiceOut *hw, int cmd, ...)
  82{
  83    (void) hw;
  84    (void) cmd;
  85    return 0;
  86}
  87
  88static 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
  95static void no_fini_in (HWVoiceIn *hw)
  96{
  97    (void) hw;
  98}
  99
 100static 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 = audio_MIN (bytes, INT_MAX);
 115        samples = bytes >> hw->info.shift;
 116        samples = audio_MIN (samples, dead);
 117    }
 118    return samples;
 119}
 120
 121static 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 = audio_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
 133static int no_ctl_in (HWVoiceIn *hw, int cmd, ...)
 134{
 135    (void) hw;
 136    (void) cmd;
 137    return 0;
 138}
 139
 140static void *no_audio_init(Audiodev *dev)
 141{
 142    return &no_audio_init;
 143}
 144
 145static void no_audio_fini (void *opaque)
 146{
 147    (void) opaque;
 148}
 149
 150static 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
 164static 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
 177static void register_audio_none(void)
 178{
 179    audio_driver_register(&no_audio_driver);
 180}
 181type_init(register_audio_none);
 182