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 size_t no_run_out(HWVoiceOut *hw, size_t live) 45 { 46 NoVoiceOut *no = (NoVoiceOut *) hw; 47 size_t 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, SIZE_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_init_out(HWVoiceOut *hw, struct audsettings *as, void *drv_opaque) 65 { 66 audio_pcm_init_info (&hw->info, as); 67 hw->samples = 1024; 68 return 0; 69 } 70 71 static void no_fini_out (HWVoiceOut *hw) 72 { 73 (void) hw; 74 } 75 76 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...) 77 { 78 (void) hw; 79 (void) cmd; 80 return 0; 81 } 82 83 static int no_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque) 84 { 85 audio_pcm_init_info (&hw->info, as); 86 hw->samples = 1024; 87 return 0; 88 } 89 90 static void no_fini_in (HWVoiceIn *hw) 91 { 92 (void) hw; 93 } 94 95 static size_t no_run_in(HWVoiceIn *hw) 96 { 97 NoVoiceIn *no = (NoVoiceIn *) hw; 98 size_t live = audio_pcm_hw_get_live_in(hw); 99 size_t dead = hw->samples - live; 100 size_t samples = 0; 101 102 if (dead) { 103 int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 104 int64_t ticks = now - no->old_ticks; 105 int64_t bytes = 106 muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND); 107 108 no->old_ticks = now; 109 bytes = MIN (bytes, SIZE_MAX); 110 samples = bytes >> hw->info.shift; 111 samples = MIN (samples, dead); 112 } 113 return samples; 114 } 115 116 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...) 117 { 118 (void) hw; 119 (void) cmd; 120 return 0; 121 } 122 123 static void *no_audio_init(Audiodev *dev) 124 { 125 return &no_audio_init; 126 } 127 128 static void no_audio_fini (void *opaque) 129 { 130 (void) opaque; 131 } 132 133 static struct audio_pcm_ops no_pcm_ops = { 134 .init_out = no_init_out, 135 .fini_out = no_fini_out, 136 .run_out = no_run_out, 137 .ctl_out = no_ctl_out, 138 139 .init_in = no_init_in, 140 .fini_in = no_fini_in, 141 .run_in = no_run_in, 142 .ctl_in = no_ctl_in 143 }; 144 145 static struct audio_driver no_audio_driver = { 146 .name = "none", 147 .descr = "Timer based audio emulation", 148 .init = no_audio_init, 149 .fini = no_audio_fini, 150 .pcm_ops = &no_pcm_ops, 151 .can_be_default = 1, 152 .max_voices_out = INT_MAX, 153 .max_voices_in = INT_MAX, 154 .voice_size_out = sizeof (NoVoiceOut), 155 .voice_size_in = sizeof (NoVoiceIn) 156 }; 157 158 static void register_audio_none(void) 159 { 160 audio_driver_register(&no_audio_driver); 161 } 162 type_init(register_audio_none); 163