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#include <stdlib.h>
#include <stdint.h>
#include "encoding.h"
#include "platform.h"
#include "prci_driver.h"
#include "eos.h"
#include "i2s.h"
#include "i2c.h"
int eos_i2c_init(uint8_t wakeup_cause) {
GPIO_REG(GPIO_IOF_SEL) &= ~IOF0_I2C0_MASK;
return EOS_OK;
}
int eos_i2c_start(uint32_t baud_rate) {
if (eos_i2s_running()) return EOS_ERR_BUSY;
eos_i2c_set_baud_rate(baud_rate);
GPIO_REG(GPIO_IOF_EN) |= IOF0_I2C0_MASK;
return EOS_OK;
}
void eos_i2c_stop(void) {
if (eos_i2s_running()) return;
GPIO_REG(GPIO_IOF_EN) &= ~IOF0_I2C0_MASK;
}
void eos_i2c_set_baud_rate(uint32_t baud_rate) {
unsigned long clock_rate = PRCI_get_cpu_freq();
uint16_t prescaler = (clock_rate / (baud_rate * 5)) - 1;
I2C0_REGB(I2C_CONTROL) &= ~I2C_CONTROL_EN;
I2C0_REGB(I2C_PRESCALE_LOW) = prescaler & 0xFF;
I2C0_REGB(I2C_PRESCALE_HIGH) = (prescaler >> 8) & 0xFF;
I2C0_REGB(I2C_CONTROL) |= I2C_CONTROL_EN;
}
static int i2c_read(uint8_t cmd) {
I2C0_REGB(I2C_COMMAND) = I2C_CMD_READ | cmd;
while (I2C0_REGB(I2C_STATUS) & I2C_STATUS_TIP);
return I2C0_REGB(I2C_RECEIVE);
}
static int i2c_write(uint8_t cmd, uint8_t b) {
I2C0_REGB(I2C_TRANSMIT) = b;
I2C0_REGB(I2C_COMMAND) = I2C_CMD_WRITE | cmd;
while (I2C0_REGB(I2C_STATUS) & I2C_STATUS_TIP);
if (I2C0_REGB(I2C_STATUS) & I2C_STATUS_RXACK) return EOS_ERR;
return EOS_OK;
}
static int i2c_addr(uint8_t addr, uint8_t rw_flag) {
return i2c_write(I2C_CMD_START, ((addr & 0x7F) << 1) | (rw_flag & 0x1));
}
int eos_i2c_read(uint8_t addr, uint8_t reg, uint8_t *buffer, uint16_t len) {
int rv;
int i;
rv = i2c_addr(addr, I2C_WRITE);
if (rv) return rv;
rv = i2c_write(0, reg);
if (rv) return rv;
rv = i2c_addr(addr, I2C_READ);
if (rv) return rv;
for (i=0; i<len; i++) {
rv = i2c_read(i == (len - 1) ? (I2C_CMD_ACK | I2C_CMD_STOP) : 0); /* Set NACK to end read, and generate STOP condition */
if (rv < 0) return rv;
buffer[i] = (uint8_t)rv;
}
return EOS_OK;
}
int eos_i2c_write(uint8_t addr, uint8_t reg, uint8_t *buffer, uint16_t len) {
int rv;
int i;
rv = i2c_addr(addr, I2C_WRITE);
if (rv) return rv;
rv = i2c_write(0, reg);
if (rv) return rv;
for (i=0; i<len; i++) {
rv = i2c_write(i == (len - 1) ? I2C_CMD_STOP : 0, buffer[i]);
if (rv) return rv;
}
return EOS_OK;
}
int eos_i2c_read8(uint8_t addr, uint8_t reg, uint8_t *data) {
return eos_i2c_read(addr, reg, data, 1);
}
int eos_i2c_write8(uint8_t addr, uint8_t reg, uint8_t data) {
return eos_i2c_write(addr, reg, &data, 1);
}
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