Add access control support to qemu bridge helper
[qemu.git] / hw / 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 "hw.h"
26 #include "pc.h"
27 #include "isa.h"
28 #include "audio/audio.h"
29 #include "qemu-timer.h"
30
31 #define PCSPK_BUF_LEN 1792
32 #define PCSPK_SAMPLE_RATE 32000
33 #define PCSPK_MAX_FREQ (PCSPK_SAMPLE_RATE >> 1)
34 #define PCSPK_MIN_COUNT ((PIT_FREQ + PCSPK_MAX_FREQ - 1) / PCSPK_MAX_FREQ)
35
36 typedef struct {
37 uint8_t sample_buf[PCSPK_BUF_LEN];
38 QEMUSoundCard card;
39 SWVoiceOut *voice;
40 ISADevice *pit;
41 unsigned int pit_count;
42 unsigned int samples;
43 unsigned int play_pos;
44 int data_on;
45 int dummy_refresh_clock;
46 } PCSpkState;
47
48 static const char *s_spk = "pcspk";
49 static PCSpkState pcspk_state;
50
51 static inline void generate_samples(PCSpkState *s)
52 {
53 unsigned int i;
54
55 if (s->pit_count) {
56 const uint32_t m = PCSPK_SAMPLE_RATE * s->pit_count;
57 const uint32_t n = ((uint64_t)PIT_FREQ << 32) / m;
58
59 /* multiple of wavelength for gapless looping */
60 s->samples = (PCSPK_BUF_LEN * PIT_FREQ / m * m / (PIT_FREQ >> 1) + 1) >> 1;
61 for (i = 0; i < s->samples; ++i)
62 s->sample_buf[i] = (64 & (n * i >> 25)) - 32;
63 } else {
64 s->samples = PCSPK_BUF_LEN;
65 for (i = 0; i < PCSPK_BUF_LEN; ++i)
66 s->sample_buf[i] = 128; /* silence */
67 }
68 }
69
70 static void pcspk_callback(void *opaque, int free)
71 {
72 PCSpkState *s = opaque;
73 unsigned int n;
74
75 if (pit_get_mode(s->pit, 2) != 3)
76 return;
77
78 n = pit_get_initial_count(s->pit, 2);
79 /* avoid frequencies that are not reproducible with sample rate */
80 if (n < PCSPK_MIN_COUNT)
81 n = 0;
82
83 if (s->pit_count != n) {
84 s->pit_count = n;
85 s->play_pos = 0;
86 generate_samples(s);
87 }
88
89 while (free > 0) {
90 n = audio_MIN(s->samples - s->play_pos, (unsigned int)free);
91 n = AUD_write(s->voice, &s->sample_buf[s->play_pos], n);
92 if (!n)
93 break;
94 s->play_pos = (s->play_pos + n) % s->samples;
95 free -= n;
96 }
97 }
98
99 int pcspk_audio_init(ISABus *bus)
100 {
101 PCSpkState *s = &pcspk_state;
102 struct audsettings as = {PCSPK_SAMPLE_RATE, 1, AUD_FMT_U8, 0};
103
104 AUD_register_card(s_spk, &s->card);
105
106 s->voice = AUD_open_out(&s->card, s->voice, s_spk, s, pcspk_callback, &as);
107 if (!s->voice) {
108 AUD_log(s_spk, "Could not open voice\n");
109 return -1;
110 }
111
112 return 0;
113 }
114
115 static uint32_t pcspk_ioport_read(void *opaque, uint32_t addr)
116 {
117 PCSpkState *s = opaque;
118 int out;
119
120 s->dummy_refresh_clock ^= (1 << 4);
121 out = pit_get_out(s->pit, 2, qemu_get_clock_ns(vm_clock)) << 5;
122
123 return pit_get_gate(s->pit, 2) | (s->data_on << 1) | s->dummy_refresh_clock | out;
124 }
125
126 static void pcspk_ioport_write(void *opaque, uint32_t addr, uint32_t val)
127 {
128 PCSpkState *s = opaque;
129 const int gate = val & 1;
130
131 s->data_on = (val >> 1) & 1;
132 pit_set_gate(s->pit, 2, gate);
133 if (s->voice) {
134 if (gate) /* restart */
135 s->play_pos = 0;
136 AUD_set_active_out(s->voice, gate & s->data_on);
137 }
138 }
139
140 void pcspk_init(ISADevice *pit)
141 {
142 PCSpkState *s = &pcspk_state;
143
144 s->pit = pit;
145 register_ioport_read(0x61, 1, 1, pcspk_ioport_read, s);
146 register_ioport_write(0x61, 1, 1, pcspk_ioport_write, s);
147 }