1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
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
13 EXPORT_SYMBOL(snd_gf1_atten_table); /* for snd-gus-synth module */
14
15 unsigned 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 0
44
45 unsigned 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
60 unsigned 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, 52
70 };
71 unsigned short range, increment, value, i;
72
73 start >>= 4;
74 end >>= 4;
75 if (start < end)
76 us /= end - start;
77 else
78 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 } else
88 value <<= 3;
89 }
90 if (range == 4) {
91 range = 3;
92 increment = 1;
93 } else
94 increment = (value + (value >> 1)) / us;
95 return (range << 6) | (increment & 0x3f);
96 }
97
98 #endif /* 0 */
99
100 unsigned 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 snd_printk(KERN_ERR "snd_gf1_translate_freq: overflow - freq = 0x%x\n", freq16);
108 }
109 return ((freq16 << 9) + (gus->gf1.playback_freq >> 1)) / gus->gf1.playback_freq;
110 }
111
112 #if 0
113
114 short snd_gf1_compute_vibrato(short cents, unsigned short fc_register)
115 {
116 static const short vibrato_table[] =
117 {
118 0, 0, 32, 592, 61, 1175, 93, 1808,
119 124, 2433, 152, 3007, 182, 3632, 213, 4290,
120 241, 4834, 255, 5200
121 };
122
123 long depth;
124 const short *vi1, *vi2;
125 short pcents, v1;
126
127 pcents = cents < 0 ? -cents : cents;
128 for (vi1 = vibrato_table, vi2 = vi1 + 2; pcents > *vi2; vi1 = vi2, vi2 += 2);
129 v1 = *(vi1 + 1);
130 /* The FC table above is a list of pairs. The first number in the pair */
131 /* is the cents index from 0-255 cents, and the second number in the */
132 /* pair is the FC adjustment needed to change the pitch by the indexed */
133 /* number of cents. The table was created for an FC of 32768. */
134 /* The following expression does a linear interpolation against the */
135 /* approximated log curve in the table above, and then scales the number */
136 /* by the FC before the LFO. This calculation also adjusts the output */
137 /* value to produce the appropriate depth for the hardware. The depth */
138 /* is 2 * desired FC + 1. */
139 depth = (((int) (*(vi2 + 1) - *vi1) * (pcents - *vi1) / (*vi2 - *vi1)) + v1) * fc_register >> 14;
140 if (depth)
141 depth++;
142 if (depth > 255)
143 depth = 255;
144 return cents < 0 ? -(short) depth : (short) depth;
145 }
146
147 unsigned short snd_gf1_compute_pitchbend(unsigned short pitchbend, unsigned short sens)
148 {
149 static const long log_table[] = {1024, 1085, 1149, 1218, 1290, 1367, 1448, 1534, 1625, 1722, 1825, 1933};
150 int wheel, sensitivity;
151 unsigned int mantissa, f1, f2;
152 unsigned short semitones, f1_index, f2_index, f1_power, f2_power;
153 char bend_down = 0;
154 int bend;
155
156 if (!sens)
157 return 1024;
158 wheel = (int) pitchbend - 8192;
159 sensitivity = ((int) sens * wheel) / 128;
160 if (sensitivity < 0) {
161 bend_down = 1;
162 sensitivity = -sensitivity;
163 }
164 semitones = (unsigned int) (sensitivity >> 13);
165 mantissa = sensitivity % 8192;
166 f1_index = semitones % 12;
167 f2_index = (semitones + 1) % 12;
168 f1_power = semitones / 12;
169 f2_power = (semitones + 1) / 12;
170 f1 = log_table[f1_index] << f1_power;
171 f2 = log_table[f2_index] << f2_power;
172 bend = (int) ((((f2 - f1) * mantissa) >> 13) + f1);
173 if (bend_down)
174 bend = 1048576L / bend;
175 return bend;
176 }
177
178 unsigned short snd_gf1_compute_freq(unsigned int freq,
179 unsigned int rate,
180 unsigned short mix_rate)
181 {
182 unsigned int fc;
183 int scale = 0;
184
185 while (freq >= 4194304L) {
186 scale++;
187 freq >>= 1;
188 }
189 fc = (freq << 10) / rate;
190 if (fc > 97391L) {
191 fc = 97391;
192 snd_printk(KERN_ERR "patch: (1) fc frequency overflow - %u\n", fc);
193 }
194 fc = (fc * 44100UL) / mix_rate;
195 while (scale--)
196 fc <<= 1;
197 if (fc > 65535L) {
198 fc = 65535;
199 snd_printk(KERN_ERR "patch: (2) fc frequency overflow - %u\n", fc);
200 }
201 return (unsigned short) fc;
202 }
203
204 #endif /* 0 */
205
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