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