hw/audio/pcspk.c

   1 /*
   2  * QEMU PC speaker emulation
   3  *
   4  * Copyright (c) 2006 Joachim Henke
   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 "hw/isa/isa.h"
  27 #include "hw/audio/soundhw.h"
  28 #include "audio/audio.h"
  29 #include "qemu/module.h"
  30 #include "qemu/timer.h"
  31 #include "qemu/error-report.h"
  32 #include "hw/timer/i8254.h"
  33 #include "migration/vmstate.h"
  34 #include "hw/audio/pcspk.h"
  35 #include "qapi/error.h"
  36 #include "qom/object.h"
  37
  38 #define PCSPK_BUF_LEN 1792
  39 #define PCSPK_SAMPLE_RATE 32000
  40 #define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1)
  41 #define PCSPK_MIN_COUNT DIV_ROUND_UP(PIT_FREQ, PCSPK_MAX_FREQ)
  42
  43 OBJECT_DECLARE_SIMPLE_TYPE(PCSpkState, PC_SPEAKER)
  44
  45 struct PCSpkState {
  46     ISADevice parent_obj;
  47
  48     MemoryRegion ioport;
  49     uint32_t iobase;
  50     uint8_t sample_buf[PCSPK_BUF_LEN];
  51     QEMUSoundCard card;
  52     SWVoiceOut *voice;
  53     void *pit;
  54     unsigned int pit_count;
  55     unsigned int samples;
  56     unsigned int play_pos;
  57     uint8_t data_on;
  58     uint8_t dummy_refresh_clock;
  59     bool migrate;
  60 };
  61
  62 static const char *s_spk = "pcspk";
  63 static PCSpkState *pcspk_state;
  64
  65 static inline void generate_samples(PCSpkState *s)
  66 {
  67     unsigned int i;
  68
  69     if (s->pit_count) {
  70         const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
  71         const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m;
  72
  73         /* multiple of wavelength for gapless looping */
  74         s->samples = (QEMU_ALIGN_DOWN(PCSPK_BUF_LEN * PIT_FREQ, m) / (PIT_FREQ >> 1) + 1) >> 1;
  75         for (i = 0; i < s->samples; ++i)
  76             s->sample_buf[i] = (64 & (n * i >> 25)) - 32;
  77     } else {
  78         s->samples = PCSPK_BUF_LEN;
  79         for (i = 0; i < PCSPK_BUF_LEN; ++i)
  80             s->sample_buf[i] = 128; /* silence */
  81     }
  82 }
  83
  84 static void pcspk_callback(void *opaque, int free)
  85 {
  86     PCSpkState *s = opaque;
  87     PITChannelInfo ch;
  88     unsigned int n;
  89
  90     pit_get_channel_info(s->pit, 2, &ch);
  91
  92     if (ch.mode != 3) {
  93         return;
  94     }
  95
  96     n = ch.initial_count;
  97     /* avoid frequencies that are not reproducible with sample rate */
  98     if (n < PCSPK_MIN_COUNT)
  99         n = 0;
 100
 101     if (s->pit_count != n) {
 102         s->pit_count = n;
 103         s->play_pos = 0;
 104         generate_samples(s);
 105     }
 106
 107     while (free > 0) {
 108         n = MIN(s->samples - s->play_pos, (unsigned int)free);
 109         n = AUD_write(s->voice, &s->sample_buf[s->play_pos], n);
 110         if (!n)
 111             break;
 112         s->play_pos = (s->play_pos + n) % s->samples;
 113         free -= n;
 114     }
 115 }
 116
 117 static int pcspk_audio_init(PCSpkState *s)
 118 {
 119     struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUDIO_FORMAT_U8, 0};
 120
 121     if (s->voice) {
 122         /* already initialized */
 123         return 0;
 124     }
 125
 126     s->voice = AUD_open_out(&s->card, s->voice, s_spk, s, pcspk_callback, &as);
 127     if (!s->voice) {
 128         AUD_log(s_spk, "Could not open voice\n");
 129         return -1;
 130     }
 131
 132     return 0;
 133 }
 134
 135 static uint64_t pcspk_io_read(void *opaque, hwaddr addr,
 136                               unsigned size)
 137 {
 138     PCSpkState *s = opaque;
 139     PITChannelInfo ch;
 140
 141     pit_get_channel_info(s->pit, 2, &ch);
 142
 143     s->dummy_refresh_clock ^= (1 << 4);
 144
 145     return ch.gate | (s->data_on << 1) | s->dummy_refresh_clock |
 146        (ch.out << 5);
 147 }
 148
 149 static void pcspk_io_write(void *opaque, hwaddr addr, uint64_t val,
 150                            unsigned size)
 151 {
 152     PCSpkState *s = opaque;
 153     const int gate = val & 1;
 154
 155     s->data_on = (val >> 1) & 1;
 156     pit_set_gate(s->pit, 2, gate);
 157     if (s->voice) {
 158         if (gate) /* restart */
 159             s->play_pos = 0;
 160         AUD_set_active_out(s->voice, gate & s->data_on);
 161     }
 162 }
 163
 164 static const MemoryRegionOps pcspk_io_ops = {
 165     .read = pcspk_io_read,
 166     .write = pcspk_io_write,
 167     .impl = {
 168         .min_access_size = 1,
 169         .max_access_size = 1,
 170     },
 171 };
 172
 173 static void pcspk_initfn(Object *obj)
 174 {
 175     PCSpkState *s = PC_SPEAKER(obj);
 176
 177     memory_region_init_io(&s->ioport, OBJECT(s), &pcspk_io_ops, s, "pcspk", 1);
 178
 179     object_property_add_link(obj, "pit", TYPE_PIT_COMMON,
 180                              (Object **)&s->pit,
 181                              qdev_prop_allow_set_link_before_realize,
 182                              0);
 183 }
 184
 185 static void pcspk_realizefn(DeviceState *dev, Error **errp)
 186 {
 187     ISADevice *isadev = ISA_DEVICE(dev);
 188     PCSpkState *s = PC_SPEAKER(dev);
 189
 190     isa_register_ioport(isadev, &s->ioport, s->iobase);
 191
 192     if (s->card.state && AUD_register_card(s_spk, &s->card, errp)) {
 193         pcspk_audio_init(s);
 194     }
 195
 196     pcspk_state = s;
 197 }
 198
 199 static bool migrate_needed(void *opaque)
 200 {
 201     PCSpkState *s = opaque;
 202
 203     return s->migrate;
 204 }
 205
 206 static const VMStateDescription vmstate_spk = {
 207     .name = "pcspk",
 208     .version_id = 1,
 209     .minimum_version_id = 1,
 210     .needed = migrate_needed,
 211     .fields = (const VMStateField[]) {
 212         VMSTATE_UINT8(data_on, PCSpkState),
 213         VMSTATE_UINT8(dummy_refresh_clock, PCSpkState),
 214         VMSTATE_END_OF_LIST()
 215     }
 216 };
 217
 218 static Property pcspk_properties[] = {
 219     DEFINE_AUDIO_PROPERTIES(PCSpkState, card),
 220     DEFINE_PROP_UINT32("iobase", PCSpkState, iobase,  0x61),
 221     DEFINE_PROP_BOOL("migrate", PCSpkState, migrate,  true),
 222     DEFINE_PROP_END_OF_LIST(),
 223 };
 224
 225 static void pcspk_class_initfn(ObjectClass *klass, void *data)
 226 {
 227     DeviceClass *dc = DEVICE_CLASS(klass);
 228
 229     dc->realize = pcspk_realizefn;
 230     set_bit(DEVICE_CATEGORY_SOUND, dc->categories);
 231     dc->vmsd = &vmstate_spk;
 232     device_class_set_props(dc, pcspk_properties);
 233     /* Reason: realize sets global pcspk_state */
 234     /* Reason: pit object link */
 235     dc->user_creatable = false;
 236 }
 237
 238 static const TypeInfo pcspk_info = {
 239     .name           = TYPE_PC_SPEAKER,
 240     .parent         = TYPE_ISA_DEVICE,
 241     .instance_size  = sizeof(PCSpkState),
 242     .instance_init  = pcspk_initfn,
 243     .class_init     = pcspk_class_initfn,
 244 };
 245
 246 static void pcspk_register(void)
 247 {
 248     type_register_static(&pcspk_info);
 249 }
 250 type_init(pcspk_register)