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 "qemu/host-utils.h" 27 #include "audio.h" 28 #include "qemu/timer.h" 29 30 #define AUDIO_CAP "noaudio" 31 #include "audio_int.h" 32 33 typedef struct NoVoiceOut { 34 HWVoiceOut hw; 35 int64_t old_ticks; 36 } NoVoiceOut; 37 38 typedef struct NoVoiceIn { 39 HWVoiceIn hw; 40 int64_t old_ticks; 41 } NoVoiceIn; 42 43 static int no_run_out (HWVoiceOut *hw, int live) 44 { 45 NoVoiceOut *no = (NoVoiceOut *) hw; 46 int decr, samples; 47 int64_t now; 48 int64_t ticks; 49 int64_t bytes; 50 51 now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 52 ticks = now - no->old_ticks; 53 bytes = muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND); 54 bytes = audio_MIN(bytes, INT_MAX); 55 samples = bytes >> hw->info.shift; 56 57 no->old_ticks = now; 58 decr = audio_MIN (live, samples); 59 hw->rpos = (hw->rpos + decr) % hw->samples; 60 return decr; 61 } 62 63 static int no_write (SWVoiceOut *sw, void *buf, int len) 64 { 65 return audio_pcm_sw_write(sw, buf, len); 66 } 67 68 static int no_init_out(HWVoiceOut *hw, struct audsettings *as, void *drv_opaque) 69 { 70 audio_pcm_init_info (&hw->info, as); 71 hw->samples = 1024; 72 return 0; 73 } 74 75 static void no_fini_out (HWVoiceOut *hw) 76 { 77 (void) hw; 78 } 79 80 static int no_ctl_out (HWVoiceOut *hw, int cmd, ...) 81 { 82 (void) hw; 83 (void) cmd; 84 return 0; 85 } 86 87 static int no_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque) 88 { 89 audio_pcm_init_info (&hw->info, as); 90 hw->samples = 1024; 91 return 0; 92 } 93 94 static void no_fini_in (HWVoiceIn *hw) 95 { 96 (void) hw; 97 } 98 99 static int no_run_in (HWVoiceIn *hw) 100 { 101 NoVoiceIn *no = (NoVoiceIn *) hw; 102 int live = audio_pcm_hw_get_live_in (hw); 103 int dead = hw->samples - live; 104 int samples = 0; 105 106 if (dead) { 107 int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 108 int64_t ticks = now - no->old_ticks; 109 int64_t bytes = 110 muldiv64(ticks, hw->info.bytes_per_second, NANOSECONDS_PER_SECOND); 111 112 no->old_ticks = now; 113 bytes = audio_MIN (bytes, INT_MAX); 114 samples = bytes >> hw->info.shift; 115 samples = audio_MIN (samples, dead); 116 } 117 return samples; 118 } 119 120 static int no_read (SWVoiceIn *sw, void *buf, int size) 121 { 122 /* use custom code here instead of audio_pcm_sw_read() to avoid 123 * useless resampling/mixing */ 124 int samples = size >> sw->info.shift; 125 int total = sw->hw->total_samples_captured - sw->total_hw_samples_acquired; 126 int to_clear = audio_MIN (samples, total); 127 sw->total_hw_samples_acquired += total; 128 audio_pcm_info_clear_buf (&sw->info, buf, to_clear); 129 return to_clear << sw->info.shift; 130 } 131 132 static int no_ctl_in (HWVoiceIn *hw, int cmd, ...) 133 { 134 (void) hw; 135 (void) cmd; 136 return 0; 137 } 138 139 static void *no_audio_init (void) 140 { 141 return &no_audio_init; 142 } 143 144 static void no_audio_fini (void *opaque) 145 { 146 (void) opaque; 147 } 148 149 static struct audio_pcm_ops no_pcm_ops = { 150 .init_out = no_init_out, 151 .fini_out = no_fini_out, 152 .run_out = no_run_out, 153 .write = no_write, 154 .ctl_out = no_ctl_out, 155 156 .init_in = no_init_in, 157 .fini_in = no_fini_in, 158 .run_in = no_run_in, 159 .read = no_read, 160 .ctl_in = no_ctl_in 161 }; 162 163 struct audio_driver no_audio_driver = { 164 .name = "none", 165 .descr = "Timer based audio emulation", 166 .options = NULL, 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