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