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
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 0
44
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, 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
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		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
114short 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
147unsigned 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
178unsigned 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