sound/isa/gus/gus_volume.c

   1 /*
   2  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   3  *
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation; either version 2 of the License, or
   8  *   (at your option) any later version.
   9  *
  10  *   This program is distributed in the hope that it will be useful,
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *   GNU General Public License for more details.
  14  *
  15  *   You should have received a copy of the GNU General Public License
  16  *   along with this program; if not, write to the Free Software
  17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  18  *
  19  */
  20
  21 #include <sound/driver.h>
  22 #include <linux/time.h>
  23 #include <sound/core.h>
  24 #include <sound/gus.h>
  25 #define __GUS_TABLES_ALLOC__
  26 #include "gus_tables.h"
  27
  28 EXPORT_SYMBOL(snd_gf1_atten_table); /* for snd-gus-synth module */
  29
  30 unsigned short snd_gf1_lvol_to_gvol_raw(unsigned int vol)
  31 {
  32         unsigned short e, m, tmp;
  33
  34         if (vol > 65535)
  35                 vol = 65535;
  36         tmp = vol;
  37         e = 7;
  38         if (tmp < 128) {
  39                 while (e > 0 && tmp < (1 << e))
  40                         e--;
  41         } else {
  42                 while (tmp > 255) {
  43                         tmp >>= 1;
  44                         e++;
  45                 }
  46         }
  47         m = vol - (1 << e);
  48         if (m > 0) {
  49                 if (e > 8)
  50                         m >>= e - 8;
  51                 else if (e < 8)
  52                         m <<= 8 - e;
  53                 m &= 255;
  54         }
  55         return (e << 8) | m;
  56 }
  57
  58 unsigned int snd_gf1_gvol_to_lvol_raw(unsigned short gf1_vol)
  59 {
  60         unsigned int rvol;
  61         unsigned short e, m;
  62
  63         if (!gf1_vol)
  64                 return 0;
  65         e = gf1_vol >> 8;
  66         m = (unsigned char) gf1_vol;
  67         rvol = 1 << e;
  68         if (e > 8)
  69                 return rvol | (m << (e - 8));
  70         return rvol | (m >> (8 - e));
  71 }
  72
  73 unsigned int snd_gf1_calc_ramp_rate(snd_gus_card_t * gus,
  74                                     unsigned short start,
  75                                     unsigned short end,
  76                                     unsigned int us)
  77 {
  78         static unsigned char vol_rates[19] =
  79         {
  80                 23, 24, 26, 28, 29, 31, 32, 34,
  81                 36, 37, 39, 40, 42, 44, 45, 47,
  82                 49, 50, 52
  83         };
  84         unsigned short range, increment, value, i;
  85
  86         start >>= 4;
  87         end >>= 4;
  88         if (start < end)
  89                 us /= end - start;
  90         else
  91                 us /= start - end;
  92         range = 4;
  93         value = gus->gf1.enh_mode ?
  94             vol_rates[0] :
  95             vol_rates[gus->gf1.active_voices - 14];
  96         for (i = 0; i < 3; i++) {
  97                 if (us < value) {
  98                         range = i;
  99                         break;
 100                 } else
 101                         value <<= 3;
 102         }
 103         if (range == 4) {
 104                 range = 3;
 105                 increment = 1;
 106         } else
 107                 increment = (value + (value >> 1)) / us;
 108         return (range << 6) | (increment & 0x3f);
 109 }
 110
 111 unsigned short snd_gf1_translate_freq(snd_gus_card_t * gus, unsigned int freq16)
 112 {
 113         freq16 >>= 3;
 114         if (freq16 < 50)
 115                 freq16 = 50;
 116         if (freq16 & 0xf8000000) {
 117                 freq16 = ~0xf8000000;
 118                 snd_printk("snd_gf1_translate_freq: overflow - freq = 0x%x\n", freq16);
 119         }
 120         return ((freq16 << 9) + (gus->gf1.playback_freq >> 1)) / gus->gf1.playback_freq;
 121 }
 122
 123 short snd_gf1_compute_vibrato(short cents, unsigned short fc_register)
 124 {
 125         static short vibrato_table[] =
 126         {
 127                 0, 0, 32, 592, 61, 1175, 93, 1808,
 128                 124, 2433, 152, 3007, 182, 3632, 213, 4290,
 129                 241, 4834, 255, 5200
 130         };
 131
 132         long depth;
 133         short *vi1, *vi2, pcents, v1;
 134
 135         pcents = cents < 0 ? -cents : cents;
 136         for (vi1 = vibrato_table, vi2 = vi1 + 2; pcents > *vi2; vi1 = vi2, vi2 += 2);
 137         v1 = *(vi1 + 1);
 138         /* The FC table above is a list of pairs. The first number in the pair     */
 139         /* is the cents index from 0-255 cents, and the second number in the       */
 140         /* pair is the FC adjustment needed to change the pitch by the indexed     */
 141         /* number of cents. The table was created for an FC of 32768.              */
 142         /* The following expression does a linear interpolation against the        */
 143         /* approximated log curve in the table above, and then scales the number   */
 144         /* by the FC before the LFO. This calculation also adjusts the output      */
 145         /* value to produce the appropriate depth for the hardware. The depth      */
 146         /* is 2 * desired FC + 1.                                                  */
 147         depth = (((int) (*(vi2 + 1) - *vi1) * (pcents - *vi1) / (*vi2 - *vi1)) + v1) * fc_register >> 14;
 148         if (depth)
 149                 depth++;
 150         if (depth > 255)
 151                 depth = 255;
 152         return cents < 0 ? -(short) depth : (short) depth;
 153 }
 154
 155 unsigned short snd_gf1_compute_pitchbend(unsigned short pitchbend, unsigned short sens)
 156 {
 157         static long log_table[] = {1024, 1085, 1149, 1218, 1290, 1367, 1448, 1534, 1625, 1722, 1825, 1933};
 158         int wheel, sensitivity;
 159         unsigned int mantissa, f1, f2;
 160         unsigned short semitones, f1_index, f2_index, f1_power, f2_power;
 161         char bend_down = 0;
 162         int bend;
 163
 164         if (!sens)
 165                 return 1024;
 166         wheel = (int) pitchbend - 8192;
 167         sensitivity = ((int) sens * wheel) / 128;
 168         if (sensitivity < 0) {
 169                 bend_down = 1;
 170                 sensitivity = -sensitivity;
 171         }
 172         semitones = (unsigned int) (sensitivity >> 13);
 173         mantissa = sensitivity % 8192;
 174         f1_index = semitones % 12;
 175         f2_index = (semitones + 1) % 12;
 176         f1_power = semitones / 12;
 177         f2_power = (semitones + 1) / 12;
 178         f1 = log_table[f1_index] << f1_power;
 179         f2 = log_table[f2_index] << f2_power;
 180         bend = (int) ((((f2 - f1) * mantissa) >> 13) + f1);
 181         if (bend_down)
 182                 bend = 1048576L / bend;
 183         return bend;
 184 }
 185
 186 unsigned short snd_gf1_compute_freq(unsigned int freq,
 187                                     unsigned int rate,
 188                                     unsigned short mix_rate)
 189 {
 190         unsigned int fc;
 191         int scale = 0;
 192
 193         while (freq >= 4194304L) {
 194                 scale++;
 195                 freq >>= 1;
 196         }
 197         fc = (freq << 10) / rate;
 198         if (fc > 97391L) {
 199                 fc = 97391;
 200                 snd_printk("patch: (1) fc frequency overflow - %u\n", fc);
 201         }
 202         fc = (fc * 44100UL) / mix_rate;
 203         while (scale--)
 204                 fc <<= 1;
 205         if (fc > 65535L) {
 206                 fc = 65535;
 207                 snd_printk("patch: (2) fc frequency overflow - %u\n", fc);
 208         }
 209         return (unsigned short) fc;
 210 }