1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/*
* rl6231.c - RL6231 class device shared support
*
* Copyright 2014 Realtek Semiconductor Corp.
*
* Author: Oder Chiou <oder_chiou@realtek.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/regmap.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/spi/spi.h>
#include <linux/acpi.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/soc-dapm.h>
#include <sound/initval.h>
#include <sound/tlv.h>
#include "rl6231.h"
/**
* rl6231_calc_dmic_clk - Calculate the parameter of dmic.
*
* @rate: base clock rate.
*
* Choose dmic clock between 1MHz and 3MHz.
* It is better for clock to approximate 3MHz.
*/
int rl6231_calc_dmic_clk(int rate)
{
int div[] = {2, 3, 4, 6, 8, 12}, idx = -EINVAL;
int i, red, bound, temp;
red = 3000000 * 12;
for (i = 0; i < ARRAY_SIZE(div); i++) {
bound = div[i] * 3000000;
if (rate > bound)
continue;
temp = bound - rate;
if (temp < red) {
red = temp;
idx = i;
}
}
return idx;
}
EXPORT_SYMBOL_GPL(rl6231_calc_dmic_clk);
/**
* rl6231_pll_calc - Calcualte PLL M/N/K code.
* @freq_in: external clock provided to codec.
* @freq_out: target clock which codec works on.
* @pll_code: Pointer to structure with M, N, K and bypass flag.
*
* Calcualte M/N/K code to configure PLL for codec.
*
* Returns 0 for success or negative error code.
*/
int rl6231_pll_calc(const unsigned int freq_in,
const unsigned int freq_out, struct rl6231_pll_code *pll_code)
{
int max_n = RL6231_PLL_N_MAX, max_m = RL6231_PLL_M_MAX;
int k, red, n_t, pll_out, in_t, out_t;
int n = 0, m = 0, m_t = 0;
int red_t = abs(freq_out - freq_in);
bool bypass = false;
if (RL6231_PLL_INP_MAX < freq_in || RL6231_PLL_INP_MIN > freq_in)
return -EINVAL;
k = 100000000 / freq_out - 2;
if (k > RL6231_PLL_K_MAX)
k = RL6231_PLL_K_MAX;
for (n_t = 0; n_t <= max_n; n_t++) {
in_t = freq_in / (k + 2);
pll_out = freq_out / (n_t + 2);
if (in_t < 0)
continue;
if (in_t == pll_out) {
bypass = true;
n = n_t;
goto code_find;
}
red = abs(in_t - pll_out);
if (red < red_t) {
bypass = true;
n = n_t;
m = m_t;
if (red == 0)
goto code_find;
red_t = red;
}
for (m_t = 0; m_t <= max_m; m_t++) {
out_t = in_t / (m_t + 2);
red = abs(out_t - pll_out);
if (red < red_t) {
bypass = false;
n = n_t;
m = m_t;
if (red == 0)
goto code_find;
red_t = red;
}
}
}
pr_debug("Only get approximation about PLL\n");
code_find:
pll_code->m_bp = bypass;
pll_code->m_code = m;
pll_code->n_code = n;
pll_code->k_code = k;
return 0;
}
EXPORT_SYMBOL_GPL(rl6231_pll_calc);
int rl6231_get_clk_info(int sclk, int rate)
{
int i, pd[] = {1, 2, 3, 4, 6, 8, 12, 16};
if (sclk <= 0 || rate <= 0)
return -EINVAL;
rate = rate << 8;
for (i = 0; i < ARRAY_SIZE(pd); i++)
if (sclk == rate * pd[i])
return i;
return -EINVAL;
}
EXPORT_SYMBOL_GPL(rl6231_get_clk_info);
MODULE_DESCRIPTION("RL6231 class device shared support");
MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
MODULE_LICENSE("GPL v2");
|