206 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>4 */5 6#include <linux/time.h>7#include <linux/export.h>8#include <sound/core.h>9#include <sound/gus.h>10#define __GUS_TABLES_ALLOC__11#include "gus_tables.h"12 13EXPORT_SYMBOL(snd_gf1_atten_table); /* for snd-gus-synth module */14 15unsigned short snd_gf1_lvol_to_gvol_raw(unsigned int vol)16{17 unsigned short e, m, tmp;18 19 if (vol > 65535)20 vol = 65535;21 tmp = vol;22 e = 7;23 if (tmp < 128) {24 while (e > 0 && tmp < (1 << e))25 e--;26 } else {27 while (tmp > 255) {28 tmp >>= 1;29 e++;30 }31 }32 m = vol - (1 << e);33 if (m > 0) {34 if (e > 8)35 m >>= e - 8;36 else if (e < 8)37 m <<= 8 - e;38 m &= 255;39 }40 return (e << 8) | m;41}42 43#if 044 45unsigned int snd_gf1_gvol_to_lvol_raw(unsigned short gf1_vol)46{47 unsigned int rvol;48 unsigned short e, m;49 50 if (!gf1_vol)51 return 0;52 e = gf1_vol >> 8;53 m = (unsigned char) gf1_vol;54 rvol = 1 << e;55 if (e > 8)56 return rvol | (m << (e - 8));57 return rvol | (m >> (8 - e));58}59 60unsigned int snd_gf1_calc_ramp_rate(struct snd_gus_card * gus,61 unsigned short start,62 unsigned short end,63 unsigned int us)64{65 static const unsigned char vol_rates[19] =66 {67 23, 24, 26, 28, 29, 31, 32, 34,68 36, 37, 39, 40, 42, 44, 45, 47,69 49, 50, 5270 };71 unsigned short range, increment, value, i;72 73 start >>= 4;74 end >>= 4;75 if (start < end)76 us /= end - start;77 else78 us /= start - end;79 range = 4;80 value = gus->gf1.enh_mode ?81 vol_rates[0] :82 vol_rates[gus->gf1.active_voices - 14];83 for (i = 0; i < 3; i++) {84 if (us < value) {85 range = i;86 break;87 } else88 value <<= 3;89 }90 if (range == 4) {91 range = 3;92 increment = 1;93 } else94 increment = (value + (value >> 1)) / us;95 return (range << 6) | (increment & 0x3f);96}97 98#endif /* 0 */99 100unsigned short snd_gf1_translate_freq(struct snd_gus_card * gus, unsigned int freq16)101{102 freq16 >>= 3;103 if (freq16 < 50)104 freq16 = 50;105 if (freq16 & 0xf8000000) {106 freq16 = ~0xf8000000;107 dev_err(gus->card->dev, "%s: overflow - freq = 0x%x\n",108 __func__, freq16);109 }110 return ((freq16 << 9) + (gus->gf1.playback_freq >> 1)) / gus->gf1.playback_freq;111}112 113#if 0114 115short snd_gf1_compute_vibrato(short cents, unsigned short fc_register)116{117 static const short vibrato_table[] =118 {119 0, 0, 32, 592, 61, 1175, 93, 1808,120 124, 2433, 152, 3007, 182, 3632, 213, 4290,121 241, 4834, 255, 5200122 };123 124 long depth;125 const short *vi1, *vi2;126 short pcents, v1;127 128 pcents = cents < 0 ? -cents : cents;129 for (vi1 = vibrato_table, vi2 = vi1 + 2; pcents > *vi2; vi1 = vi2, vi2 += 2);130 v1 = *(vi1 + 1);131 /* The FC table above is a list of pairs. The first number in the pair */132 /* is the cents index from 0-255 cents, and the second number in the */133 /* pair is the FC adjustment needed to change the pitch by the indexed */134 /* number of cents. The table was created for an FC of 32768. */135 /* The following expression does a linear interpolation against the */136 /* approximated log curve in the table above, and then scales the number */137 /* by the FC before the LFO. This calculation also adjusts the output */138 /* value to produce the appropriate depth for the hardware. The depth */139 /* is 2 * desired FC + 1. */140 depth = (((int) (*(vi2 + 1) - *vi1) * (pcents - *vi1) / (*vi2 - *vi1)) + v1) * fc_register >> 14;141 if (depth)142 depth++;143 if (depth > 255)144 depth = 255;145 return cents < 0 ? -(short) depth : (short) depth;146}147 148unsigned short snd_gf1_compute_pitchbend(unsigned short pitchbend, unsigned short sens)149{150 static const long log_table[] = {1024, 1085, 1149, 1218, 1290, 1367, 1448, 1534, 1625, 1722, 1825, 1933};151 int wheel, sensitivity;152 unsigned int mantissa, f1, f2;153 unsigned short semitones, f1_index, f2_index, f1_power, f2_power;154 char bend_down = 0;155 int bend;156 157 if (!sens)158 return 1024;159 wheel = (int) pitchbend - 8192;160 sensitivity = ((int) sens * wheel) / 128;161 if (sensitivity < 0) {162 bend_down = 1;163 sensitivity = -sensitivity;164 }165 semitones = (unsigned int) (sensitivity >> 13);166 mantissa = sensitivity % 8192;167 f1_index = semitones % 12;168 f2_index = (semitones + 1) % 12;169 f1_power = semitones / 12;170 f2_power = (semitones + 1) / 12;171 f1 = log_table[f1_index] << f1_power;172 f2 = log_table[f2_index] << f2_power;173 bend = (int) ((((f2 - f1) * mantissa) >> 13) + f1);174 if (bend_down)175 bend = 1048576L / bend;176 return bend;177}178 179unsigned short snd_gf1_compute_freq(unsigned int freq,180 unsigned int rate,181 unsigned short mix_rate)182{183 unsigned int fc;184 int scale = 0;185 186 while (freq >= 4194304L) {187 scale++;188 freq >>= 1;189 }190 fc = (freq << 10) / rate;191 if (fc > 97391L) {192 fc = 97391;193 pr_err("patch: (1) fc frequency overflow - %u\n", fc);194 }195 fc = (fc * 44100UL) / mix_rate;196 while (scale--)197 fc <<= 1;198 if (fc > 65535L) {199 fc = 65535;200 pr_err("patch: (2) fc frequency overflow - %u\n", fc);201 }202 return (unsigned short) fc;203}204 205#endif /* 0 */206