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 32 typedef struct NoVoiceOut { 33 HWVoiceOut hw; 34 int64_t old_ticks; 35 } NoVoiceOut; 36 37 typedef struct NoVoiceIn { 38 HWVoiceIn hw; 39 int64_t old_ticks; 40 } NoVoiceIn; 41 42 static 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, get_ticks_per_sec ()); 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 62 static int no_write (SWVoiceOut *sw, void *buf, int len) 63 { 64 return audio_pcm_sw_write (sw, buf, len); 65 } 66 67 static 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 74 static void no_fini_out (HWVoiceOut *hw) 75 { 76 (void) hw; 77 } 78 79 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...) 80 { 81 (void) hw; 82 (void) cmd; 83 return 0; 84 } 85 86 static 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 93 static void no_fini_in (HWVoiceIn *hw) 94 { 95 (void) hw; 96 } 97 98 static 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, get_ticks_per_sec ()); 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 } 118 119 static 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 } 130 131 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...) 132 { 133 (void) hw; 134 (void) cmd; 135 return 0; 136 } 137 138 static void *no_audio_init (void) 139 { 140 return &no_audio_init; 141 } 142 143 static void no_audio_fini (void *opaque) 144 { 145 (void) opaque; 146 } 147 148 static 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 }; 161 162 struct 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