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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
/*
* Feb 2017 Karl Palsson <karlp@tweak.net.au>
*/
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <libopencm3/cm3/nvic.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/i2c.h>
#include <libopencm3/stm32/rcc.h>
#include "trace.h"
#define LED_DISCO_GREEN_PORT GPIOD
#define LED_DISCO_GREEN_PIN GPIO12
#define CODEC_ADDRESS 0x4a
static void codec_gpio_init(void)
{
/* reset pin */
rcc_periph_clock_enable(RCC_GPIOD);
gpio_mode_setup(GPIOD, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE, GPIO4);
/* i2c control lines */
rcc_periph_clock_enable(RCC_GPIOB);
gpio_mode_setup(GPIOB, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO6 | GPIO9);
gpio_set_output_options(GPIOB, GPIO_OTYPE_OD, GPIO_OSPEED_50MHZ, GPIO6 | GPIO9);
gpio_set_af(GPIOB, GPIO_AF4, GPIO6 | GPIO9);
}
static void codec_i2c_init(void)
{
rcc_periph_clock_enable(RCC_I2C1);
i2c_peripheral_disable(I2C1);
i2c_reset(I2C1);
i2c_set_standard_mode(I2C1);
i2c_enable_ack(I2C1);
i2c_set_dutycycle(I2C1, I2C_CCR_DUTY_DIV2); /* default, no need to do this really */
i2c_set_clock_frequency(I2C1, I2C_CR2_FREQ_42MHZ);
/* 42MHz / (100kHz * 2) */
i2c_set_ccr(I2C1, 210);
/* standard mode, freqMhz+1*/
i2c_set_trise(I2C1, 43);
i2c_peripheral_enable(I2C1);
}
static void codec_init(void)
{
int i;
/* Configure the Codec related IOs */
codec_gpio_init();
/* reset the codec */
gpio_clear(GPIOD, GPIO4);
for (i = 0; i < 1000000; i++) { /* Wait a bit. */
__asm__("NOP");
}
gpio_set(GPIOD, GPIO4);
codec_i2c_init();
}
static int codec_write_reg(uint8_t reg, uint8_t val)
{
uint32_t i2c = I2C1;
while ((I2C_SR2(i2c) & I2C_SR2_BUSY)) {
}
i2c_send_start(i2c);
/* Wait for master mode selected */
while (!((I2C_SR1(i2c) & I2C_SR1_SB)
& (I2C_SR2(i2c) & (I2C_SR2_MSL | I2C_SR2_BUSY))));
i2c_send_7bit_address(i2c, CODEC_ADDRESS, I2C_WRITE);
/* Waiting for address is transferred. */
while (!(I2C_SR1(i2c) & I2C_SR1_ADDR));
/* Cleaning ADDR condition sequence. */
uint32_t reg32 = I2C_SR2(i2c);
(void) reg32; /* unused */
/* Common above here */
/* Sending the data. */
i2c_send_data(i2c, reg);
while (!(I2C_SR1(i2c) & (I2C_SR1_BTF)));
i2c_send_data(i2c, val);
while (!(I2C_SR1(i2c) & (I2C_SR1_BTF | I2C_SR1_TxE)));
/* Send STOP condition. */
i2c_send_stop(i2c);
return 0;
}
static uint32_t codec_read_reg(uint8_t reg)
{
uint32_t i2c = I2C1;
while ((I2C_SR2(i2c) & I2C_SR2_BUSY)) {
}
i2c_send_start(i2c);
/* Wait for master mode selected */
while (!((I2C_SR1(i2c) & I2C_SR1_SB)
& (I2C_SR2(i2c) & (I2C_SR2_MSL | I2C_SR2_BUSY))));
i2c_send_7bit_address(i2c, CODEC_ADDRESS, I2C_WRITE);
/* Waiting for address is transferred. */
while (!(I2C_SR1(i2c) & I2C_SR1_ADDR));
/* Cleaning ADDR condition sequence. */
uint32_t reg32 = I2C_SR2(i2c);
(void) reg32; /* unused */
/* Common stuff ABOVE HERE */
i2c_send_data(i2c, reg);
while (!(I2C_SR1(i2c) & (I2C_SR1_BTF)));
i2c_send_start(i2c);
/* Wait for master mode selected */
while (!((I2C_SR1(i2c) & I2C_SR1_SB)
& (I2C_SR2(i2c) & (I2C_SR2_MSL | I2C_SR2_BUSY))));
i2c_send_7bit_address(i2c, CODEC_ADDRESS, I2C_READ);
/* Waiting for address is transferred. */
while (!(I2C_SR1(i2c) & I2C_SR1_ADDR));
i2c_disable_ack(i2c);
/* Cleaning ADDR condition sequence. */
reg32 = I2C_SR2(i2c);
(void) reg32; /* unused */
i2c_send_stop(i2c);
while (!(I2C_SR1(i2c) & I2C_SR1_RxNE));
uint32_t result = i2c_get_data(i2c);
i2c_enable_ack(i2c);
I2C_SR1(i2c) &= ~I2C_SR1_AF;
return result;
}
static void codec_readid(void)
{
uint8_t res = codec_read_reg(0x01);
printf("raw res = %#x Codec is %#x (should be 0x1c), revision %d\n", res, res >> 3, res & 0x7);
}
int main(void)
{
int i, j;
rcc_clock_setup_hse_3v3(&rcc_hse_8mhz_3v3[RCC_CLOCK_3V3_168MHZ]);
/* green led for ticking */
rcc_periph_clock_enable(RCC_GPIOD);
gpio_mode_setup(LED_DISCO_GREEN_PORT, GPIO_MODE_OUTPUT, GPIO_PUPD_NONE,
LED_DISCO_GREEN_PIN);
printf("hi guys!\n");
codec_init();
codec_readid();
codec_write_reg(0x14, 0xff);
for (i = 0; i < 8; i++) {
uint8_t pass_vol_a = codec_read_reg(0x14);
printf("Passthrough vol A was: %#x\n", pass_vol_a);
codec_write_reg(0x14, pass_vol_a >> 1);
gpio_toggle(LED_DISCO_GREEN_PORT, LED_DISCO_GREEN_PIN);
for (j = 0; j < 100000; j++) { /* Wait a bit. */
__asm__("NOP");
}
}
/* Nothing else to do */;
while (1) {
;
}
return 0;
}
|
