1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/*
* Copyright (c) by Jaroslav Kysela <perex@suse.cz>
* Creative Labs, Inc.
* Lee Revell <rlrevell@joe-job.com>
* Routines for control of EMU10K1 chips - voice manager
*
* Rewrote voice allocator for multichannel support - rlrevell 12/2004
*
* BUGS:
* --
*
* TODO:
* --
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <sound/driver.h>
#include <linux/time.h>
#include <sound/core.h>
#include <sound/emu10k1.h>
/* Previously the voice allocator started at 0 every time. The new voice
* allocator uses a round robin scheme. The next free voice is tracked in
* the card record and each allocation begins where the last left off. The
* hardware requires stereo interleaved voices be aligned to an even/odd
* boundary. For multichannel voice allocation we ensure than the block of
* voices does not cross the 32 voice boundary. This simplifies the
* multichannel support and ensures we can use a single write to the
* (set|clear)_loop_stop registers. Otherwise (for example) the voices would
* get out of sync when pausing/resuming a stream.
* --rlrevell
*/
static int voice_alloc(struct snd_emu10k1 *emu, int type, int number,
struct snd_emu10k1_voice **rvoice)
{
struct snd_emu10k1_voice *voice;
int i, j, k, first_voice, last_voice, skip;
*rvoice = NULL;
first_voice = last_voice = 0;
for (i = emu->next_free_voice, j = 0; j < NUM_G ; i += number, j += number) {
// printk("i %d j %d next free %d!\n", i, j, emu->next_free_voice);
i %= NUM_G;
/* stereo voices must be even/odd */
if ((number == 2) && (i % 2)) {
i++;
continue;
}
skip = 0;
for (k = 0; k < number; k++) {
voice = &emu->voices[(i+k) % NUM_G];
if (voice->use) {
skip = 1;
break;
}
}
if (!skip) {
// printk("allocated voice %d\n", i);
first_voice = i;
last_voice = (i + number) % NUM_G;
emu->next_free_voice = last_voice;
break;
}
}
if (first_voice == last_voice)
return -ENOMEM;
for (i = 0; i < number; i++) {
voice = &emu->voices[(first_voice + i) % NUM_G];
// printk("voice alloc - %i, %i of %i\n", voice->number, idx-first_voice+1, number);
voice->use = 1;
switch (type) {
case EMU10K1_PCM:
voice->pcm = 1;
break;
case EMU10K1_SYNTH:
voice->synth = 1;
break;
case EMU10K1_MIDI:
voice->midi = 1;
break;
case EMU10K1_EFX:
voice->efx = 1;
break;
}
}
*rvoice = &emu->voices[first_voice];
return 0;
}
int snd_emu10k1_voice_alloc(struct snd_emu10k1 *emu, int type, int number,
struct snd_emu10k1_voice **rvoice)
{
unsigned long flags;
int result;
snd_assert(rvoice != NULL, return -EINVAL);
snd_assert(number, return -EINVAL);
spin_lock_irqsave(&emu->voice_lock, flags);
for (;;) {
result = voice_alloc(emu, type, number, rvoice);
if (result == 0 || type == EMU10K1_SYNTH || type == EMU10K1_MIDI)
break;
/* free a voice from synth */
if (emu->get_synth_voice) {
result = emu->get_synth_voice(emu);
if (result >= 0) {
struct snd_emu10k1_voice *pvoice = &emu->voices[result];
pvoice->interrupt = NULL;
pvoice->use = pvoice->pcm = pvoice->synth = pvoice->midi = pvoice->efx = 0;
pvoice->epcm = NULL;
}
}
if (result < 0)
break;
}
spin_unlock_irqrestore(&emu->voice_lock, flags);
return result;
}
EXPORT_SYMBOL(snd_emu10k1_voice_alloc);
int snd_emu10k1_voice_free(struct snd_emu10k1 *emu,
struct snd_emu10k1_voice *pvoice)
{
unsigned long flags;
snd_assert(pvoice != NULL, return -EINVAL);
spin_lock_irqsave(&emu->voice_lock, flags);
pvoice->interrupt = NULL;
pvoice->use = pvoice->pcm = pvoice->synth = pvoice->midi = pvoice->efx = 0;
pvoice->epcm = NULL;
snd_emu10k1_voice_init(emu, pvoice->number);
spin_unlock_irqrestore(&emu->voice_lock, flags);
return 0;
}
EXPORT_SYMBOL(snd_emu10k1_voice_free);
|
