summaryrefslogtreecommitdiff
path: root/sound/isa/gus/gus_volume.c
diff options
context:
space:
mode:
Diffstat (limited to 'sound/isa/gus/gus_volume.c')
-rw-r--r--sound/isa/gus/gus_volume.c218
1 files changed, 218 insertions, 0 deletions
diff --git a/sound/isa/gus/gus_volume.c b/sound/isa/gus/gus_volume.c
new file mode 100644
index 000000000..3dd841ae7
--- /dev/null
+++ b/sound/isa/gus/gus_volume.c
@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
+ *
+ *
+ * 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 <linux/time.h>
+#include <linux/export.h>
+#include <sound/core.h>
+#include <sound/gus.h>
+#define __GUS_TABLES_ALLOC__
+#include "gus_tables.h"
+
+EXPORT_SYMBOL(snd_gf1_atten_table); /* for snd-gus-synth module */
+
+unsigned short snd_gf1_lvol_to_gvol_raw(unsigned int vol)
+{
+ unsigned short e, m, tmp;
+
+ if (vol > 65535)
+ vol = 65535;
+ tmp = vol;
+ e = 7;
+ if (tmp < 128) {
+ while (e > 0 && tmp < (1 << e))
+ e--;
+ } else {
+ while (tmp > 255) {
+ tmp >>= 1;
+ e++;
+ }
+ }
+ m = vol - (1 << e);
+ if (m > 0) {
+ if (e > 8)
+ m >>= e - 8;
+ else if (e < 8)
+ m <<= 8 - e;
+ m &= 255;
+ }
+ return (e << 8) | m;
+}
+
+#if 0
+
+unsigned int snd_gf1_gvol_to_lvol_raw(unsigned short gf1_vol)
+{
+ unsigned int rvol;
+ unsigned short e, m;
+
+ if (!gf1_vol)
+ return 0;
+ e = gf1_vol >> 8;
+ m = (unsigned char) gf1_vol;
+ rvol = 1 << e;
+ if (e > 8)
+ return rvol | (m << (e - 8));
+ return rvol | (m >> (8 - e));
+}
+
+unsigned int snd_gf1_calc_ramp_rate(struct snd_gus_card * gus,
+ unsigned short start,
+ unsigned short end,
+ unsigned int us)
+{
+ static unsigned char vol_rates[19] =
+ {
+ 23, 24, 26, 28, 29, 31, 32, 34,
+ 36, 37, 39, 40, 42, 44, 45, 47,
+ 49, 50, 52
+ };
+ unsigned short range, increment, value, i;
+
+ start >>= 4;
+ end >>= 4;
+ if (start < end)
+ us /= end - start;
+ else
+ us /= start - end;
+ range = 4;
+ value = gus->gf1.enh_mode ?
+ vol_rates[0] :
+ vol_rates[gus->gf1.active_voices - 14];
+ for (i = 0; i < 3; i++) {
+ if (us < value) {
+ range = i;
+ break;
+ } else
+ value <<= 3;
+ }
+ if (range == 4) {
+ range = 3;
+ increment = 1;
+ } else
+ increment = (value + (value >> 1)) / us;
+ return (range << 6) | (increment & 0x3f);
+}
+
+#endif /* 0 */
+
+unsigned short snd_gf1_translate_freq(struct snd_gus_card * gus, unsigned int freq16)
+{
+ freq16 >>= 3;
+ if (freq16 < 50)
+ freq16 = 50;
+ if (freq16 & 0xf8000000) {
+ freq16 = ~0xf8000000;
+ snd_printk(KERN_ERR "snd_gf1_translate_freq: overflow - freq = 0x%x\n", freq16);
+ }
+ return ((freq16 << 9) + (gus->gf1.playback_freq >> 1)) / gus->gf1.playback_freq;
+}
+
+#if 0
+
+short snd_gf1_compute_vibrato(short cents, unsigned short fc_register)
+{
+ static short vibrato_table[] =
+ {
+ 0, 0, 32, 592, 61, 1175, 93, 1808,
+ 124, 2433, 152, 3007, 182, 3632, 213, 4290,
+ 241, 4834, 255, 5200
+ };
+
+ long depth;
+ short *vi1, *vi2, pcents, v1;
+
+ pcents = cents < 0 ? -cents : cents;
+ for (vi1 = vibrato_table, vi2 = vi1 + 2; pcents > *vi2; vi1 = vi2, vi2 += 2);
+ v1 = *(vi1 + 1);
+ /* The FC table above is a list of pairs. The first number in the pair */
+ /* is the cents index from 0-255 cents, and the second number in the */
+ /* pair is the FC adjustment needed to change the pitch by the indexed */
+ /* number of cents. The table was created for an FC of 32768. */
+ /* The following expression does a linear interpolation against the */
+ /* approximated log curve in the table above, and then scales the number */
+ /* by the FC before the LFO. This calculation also adjusts the output */
+ /* value to produce the appropriate depth for the hardware. The depth */
+ /* is 2 * desired FC + 1. */
+ depth = (((int) (*(vi2 + 1) - *vi1) * (pcents - *vi1) / (*vi2 - *vi1)) + v1) * fc_register >> 14;
+ if (depth)
+ depth++;
+ if (depth > 255)
+ depth = 255;
+ return cents < 0 ? -(short) depth : (short) depth;
+}
+
+unsigned short snd_gf1_compute_pitchbend(unsigned short pitchbend, unsigned short sens)
+{
+ static long log_table[] = {1024, 1085, 1149, 1218, 1290, 1367, 1448, 1534, 1625, 1722, 1825, 1933};
+ int wheel, sensitivity;
+ unsigned int mantissa, f1, f2;
+ unsigned short semitones, f1_index, f2_index, f1_power, f2_power;
+ char bend_down = 0;
+ int bend;
+
+ if (!sens)
+ return 1024;
+ wheel = (int) pitchbend - 8192;
+ sensitivity = ((int) sens * wheel) / 128;
+ if (sensitivity < 0) {
+ bend_down = 1;
+ sensitivity = -sensitivity;
+ }
+ semitones = (unsigned int) (sensitivity >> 13);
+ mantissa = sensitivity % 8192;
+ f1_index = semitones % 12;
+ f2_index = (semitones + 1) % 12;
+ f1_power = semitones / 12;
+ f2_power = (semitones + 1) / 12;
+ f1 = log_table[f1_index] << f1_power;
+ f2 = log_table[f2_index] << f2_power;
+ bend = (int) ((((f2 - f1) * mantissa) >> 13) + f1);
+ if (bend_down)
+ bend = 1048576L / bend;
+ return bend;
+}
+
+unsigned short snd_gf1_compute_freq(unsigned int freq,
+ unsigned int rate,
+ unsigned short mix_rate)
+{
+ unsigned int fc;
+ int scale = 0;
+
+ while (freq >= 4194304L) {
+ scale++;
+ freq >>= 1;
+ }
+ fc = (freq << 10) / rate;
+ if (fc > 97391L) {
+ fc = 97391;
+ snd_printk(KERN_ERR "patch: (1) fc frequency overflow - %u\n", fc);
+ }
+ fc = (fc * 44100UL) / mix_rate;
+ while (scale--)
+ fc <<= 1;
+ if (fc > 65535L) {
+ fc = 65535;
+ snd_printk(KERN_ERR "patch: (2) fc frequency overflow - %u\n", fc);
+ }
+ return (unsigned short) fc;
+}
+
+#endif /* 0 */