root / hw / audio / pcspk.c @ 2c9b15ca
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/*
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* QEMU PC speaker emulation
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*
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* Copyright (c) 2006 Joachim Henke
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "hw/hw.h" |
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#include "hw/i386/pc.h" |
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#include "hw/isa/isa.h" |
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#include "hw/audio/audio.h" |
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#include "audio/audio.h" |
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#include "qemu/timer.h" |
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#include "hw/timer/i8254.h" |
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#include "hw/audio/pcspk.h" |
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#define PCSPK_BUF_LEN 1792 |
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#define PCSPK_SAMPLE_RATE 32000 |
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#define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1) |
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#define PCSPK_MIN_COUNT ((PIT_FREQ + PCSPK_MAX_FREQ - 1) / PCSPK_MAX_FREQ) |
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#define PC_SPEAKER(obj) OBJECT_CHECK(PCSpkState, (obj), TYPE_PC_SPEAKER)
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typedef struct { |
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ISADevice parent_obj; |
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MemoryRegion ioport; |
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uint32_t iobase; |
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uint8_t sample_buf[PCSPK_BUF_LEN]; |
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QEMUSoundCard card; |
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SWVoiceOut *voice; |
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void *pit;
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unsigned int pit_count; |
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unsigned int samples; |
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unsigned int play_pos; |
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int data_on;
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int dummy_refresh_clock;
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} PCSpkState; |
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static const char *s_spk = "pcspk"; |
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static PCSpkState *pcspk_state;
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static inline void generate_samples(PCSpkState *s) |
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{ |
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unsigned int i; |
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if (s->pit_count) {
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const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
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const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m; |
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/* multiple of wavelength for gapless looping */
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s->samples = (PCSPK_BUF_LEN * PIT_FREQ / m * m / (PIT_FREQ >> 1) + 1) >> 1; |
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for (i = 0; i < s->samples; ++i) |
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s->sample_buf[i] = (64 & (n * i >> 25)) - 32; |
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} else {
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s->samples = PCSPK_BUF_LEN; |
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for (i = 0; i < PCSPK_BUF_LEN; ++i) |
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s->sample_buf[i] = 128; /* silence */ |
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} |
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} |
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static void pcspk_callback(void *opaque, int free) |
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{ |
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PCSpkState *s = opaque; |
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PITChannelInfo ch; |
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unsigned int n; |
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pit_get_channel_info(s->pit, 2, &ch);
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if (ch.mode != 3) { |
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return;
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} |
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n = ch.initial_count; |
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/* avoid frequencies that are not reproducible with sample rate */
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if (n < PCSPK_MIN_COUNT)
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n = 0;
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if (s->pit_count != n) {
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s->pit_count = n; |
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s->play_pos = 0;
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generate_samples(s); |
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} |
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while (free > 0) { |
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n = audio_MIN(s->samples - s->play_pos, (unsigned int)free); |
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n = AUD_write(s->voice, &s->sample_buf[s->play_pos], n); |
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if (!n)
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break;
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s->play_pos = (s->play_pos + n) % s->samples; |
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free -= n; |
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} |
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} |
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static int pcspk_audio_init(ISABus *bus) |
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{ |
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PCSpkState *s = pcspk_state; |
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struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUD_FMT_U8, 0}; |
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AUD_register_card(s_spk, &s->card); |
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s->voice = AUD_open_out(&s->card, s->voice, s_spk, s, pcspk_callback, &as); |
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if (!s->voice) {
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AUD_log(s_spk, "Could not open voice\n");
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return -1; |
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} |
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return 0; |
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} |
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static uint64_t pcspk_io_read(void *opaque, hwaddr addr, |
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unsigned size)
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{ |
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PCSpkState *s = opaque; |
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PITChannelInfo ch; |
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pit_get_channel_info(s->pit, 2, &ch);
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s->dummy_refresh_clock ^= (1 << 4); |
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return ch.gate | (s->data_on << 1) | s->dummy_refresh_clock | |
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(ch.out << 5);
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} |
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static void pcspk_io_write(void *opaque, hwaddr addr, uint64_t val, |
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unsigned size)
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{ |
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PCSpkState *s = opaque; |
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const int gate = val & 1; |
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s->data_on = (val >> 1) & 1; |
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pit_set_gate(s->pit, 2, gate);
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if (s->voice) {
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if (gate) /* restart */ |
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s->play_pos = 0;
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AUD_set_active_out(s->voice, gate & s->data_on); |
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} |
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} |
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static const MemoryRegionOps pcspk_io_ops = { |
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.read = pcspk_io_read, |
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.write = pcspk_io_write, |
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.impl = { |
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.min_access_size = 1,
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.max_access_size = 1,
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}, |
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}; |
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static void pcspk_initfn(Object *obj) |
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{ |
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PCSpkState *s = PC_SPEAKER(obj); |
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memory_region_init_io(&s->ioport, NULL, &pcspk_io_ops, s, "elcr", 1); |
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} |
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static void pcspk_realizefn(DeviceState *dev, Error **errp) |
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{ |
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ISADevice *isadev = ISA_DEVICE(dev); |
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PCSpkState *s = PC_SPEAKER(dev); |
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isa_register_ioport(isadev, &s->ioport, s->iobase); |
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pcspk_state = s; |
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} |
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static Property pcspk_properties[] = {
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DEFINE_PROP_HEX32("iobase", PCSpkState, iobase, -1), |
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DEFINE_PROP_PTR("pit", PCSpkState, pit),
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DEFINE_PROP_END_OF_LIST(), |
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}; |
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static void pcspk_class_initfn(ObjectClass *klass, void *data) |
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{ |
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DeviceClass *dc = DEVICE_CLASS(klass); |
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dc->realize = pcspk_realizefn; |
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dc->no_user = 1;
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dc->props = pcspk_properties; |
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} |
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static const TypeInfo pcspk_info = { |
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.name = TYPE_PC_SPEAKER, |
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.parent = TYPE_ISA_DEVICE, |
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.instance_size = sizeof(PCSpkState),
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.instance_init = pcspk_initfn, |
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.class_init = pcspk_class_initfn, |
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}; |
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static void pcspk_register(void) |
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{ |
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type_register_static(&pcspk_info); |
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isa_register_soundhw("pcspk", "PC speaker", pcspk_audio_init); |
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} |
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type_init(pcspk_register) |