Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / sound / pci / emu10k1 / voice.c
blobf16fd5cfb7cd86cac65d882b0a3c43304ac476a3
1 /*
2 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3 * Creative Labs, Inc.
4 * Lee Revell <rlrevell@joe-job.com>
5 * Routines for control of EMU10K1 chips - voice manager
7 * Rewrote voice allocator for multichannel support - rlrevell 12/2004
8 *
9 * BUGS:
10 * --
12 * TODO:
13 * --
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31 #include <linux/time.h>
32 #include <linux/export.h>
33 #include <sound/core.h>
34 #include <sound/emu10k1.h>
36 /* Previously the voice allocator started at 0 every time. The new voice
37 * allocator uses a round robin scheme. The next free voice is tracked in
38 * the card record and each allocation begins where the last left off. The
39 * hardware requires stereo interleaved voices be aligned to an even/odd
40 * boundary. For multichannel voice allocation we ensure than the block of
41 * voices does not cross the 32 voice boundary. This simplifies the
42 * multichannel support and ensures we can use a single write to the
43 * (set|clear)_loop_stop registers. Otherwise (for example) the voices would
44 * get out of sync when pausing/resuming a stream.
45 * --rlrevell
48 static int voice_alloc(struct snd_emu10k1 *emu, int type, int number,
49 struct snd_emu10k1_voice **rvoice)
51 struct snd_emu10k1_voice *voice;
52 int i, j, k, first_voice, last_voice, skip;
54 *rvoice = NULL;
55 first_voice = last_voice = 0;
56 for (i = emu->next_free_voice, j = 0; j < NUM_G ; i += number, j += number) {
58 dev_dbg(emu->card->dev, "i %d j %d next free %d!\n",
59 i, j, emu->next_free_voice);
61 i %= NUM_G;
63 /* stereo voices must be even/odd */
64 if ((number == 2) && (i % 2)) {
65 i++;
66 continue;
69 skip = 0;
70 for (k = 0; k < number; k++) {
71 voice = &emu->voices[(i+k) % NUM_G];
72 if (voice->use) {
73 skip = 1;
74 break;
77 if (!skip) {
78 /* dev_dbg(emu->card->dev, "allocated voice %d\n", i); */
79 first_voice = i;
80 last_voice = (i + number) % NUM_G;
81 emu->next_free_voice = last_voice;
82 break;
86 if (first_voice == last_voice)
87 return -ENOMEM;
89 for (i = 0; i < number; i++) {
90 voice = &emu->voices[(first_voice + i) % NUM_G];
92 dev_dbg(emu->card->dev, "voice alloc - %i, %i of %i\n",
93 voice->number, idx-first_voice+1, number);
95 voice->use = 1;
96 switch (type) {
97 case EMU10K1_PCM:
98 voice->pcm = 1;
99 break;
100 case EMU10K1_SYNTH:
101 voice->synth = 1;
102 break;
103 case EMU10K1_MIDI:
104 voice->midi = 1;
105 break;
106 case EMU10K1_EFX:
107 voice->efx = 1;
108 break;
111 *rvoice = &emu->voices[first_voice];
112 return 0;
115 int snd_emu10k1_voice_alloc(struct snd_emu10k1 *emu, int type, int number,
116 struct snd_emu10k1_voice **rvoice)
118 unsigned long flags;
119 int result;
121 if (snd_BUG_ON(!rvoice))
122 return -EINVAL;
123 if (snd_BUG_ON(!number))
124 return -EINVAL;
126 spin_lock_irqsave(&emu->voice_lock, flags);
127 for (;;) {
128 result = voice_alloc(emu, type, number, rvoice);
129 if (result == 0 || type == EMU10K1_SYNTH || type == EMU10K1_MIDI)
130 break;
132 /* free a voice from synth */
133 if (emu->get_synth_voice) {
134 result = emu->get_synth_voice(emu);
135 if (result >= 0) {
136 struct snd_emu10k1_voice *pvoice = &emu->voices[result];
137 pvoice->interrupt = NULL;
138 pvoice->use = pvoice->pcm = pvoice->synth = pvoice->midi = pvoice->efx = 0;
139 pvoice->epcm = NULL;
142 if (result < 0)
143 break;
145 spin_unlock_irqrestore(&emu->voice_lock, flags);
147 return result;
150 EXPORT_SYMBOL(snd_emu10k1_voice_alloc);
152 int snd_emu10k1_voice_free(struct snd_emu10k1 *emu,
153 struct snd_emu10k1_voice *pvoice)
155 unsigned long flags;
157 if (snd_BUG_ON(!pvoice))
158 return -EINVAL;
159 spin_lock_irqsave(&emu->voice_lock, flags);
160 pvoice->interrupt = NULL;
161 pvoice->use = pvoice->pcm = pvoice->synth = pvoice->midi = pvoice->efx = 0;
162 pvoice->epcm = NULL;
163 snd_emu10k1_voice_init(emu, pvoice->number);
164 spin_unlock_irqrestore(&emu->voice_lock, flags);
165 return 0;
168 EXPORT_SYMBOL(snd_emu10k1_voice_free);