1 files changed, 152 insertions, 0 deletions

diff --git a/sound/pci/emu10k1/voice.c b/sound/pci/emu10k1/voice.c
new file mode 100644
index 000000000000..d251d3440eec
--- /dev/null
+++ b/sound/pci/emu10k1/voice.c
@@ -0,0 +1,152 @@
+/*
+ *  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(emu10k1_t *emu, emu10k1_voice_type_t type, int number, emu10k1_voice_t **rvoice)
+{
+        emu10k1_voice_t *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(emu10k1_t *emu, emu10k1_voice_type_t type, int number, emu10k1_voice_t **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) {
+                                emu10k1_voice_t *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;
+}
+
+int snd_emu10k1_voice_free(emu10k1_t *emu, emu10k1_voice_t *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;
+}