109 lines
3.0 KiB
C

// Copyright 2022 zvecr<git@zvecr.com>
// SPDX-License-Identifier: GPL-2.0-or-later
#include "mcp23018.h"
#include "i2c_master.h"
#include "wait.h"
#include "debug.h"
#define SLAVE_TO_ADDR(n) (n << 1)
#define TIMEOUT 100
enum {
CMD_IODIRA = 0x00, // i/o direction register
CMD_IODIRB = 0x01,
CMD_GPPUA = 0x0C, // GPIO pull-up resistor register
CMD_GPPUB = 0x0D,
CMD_GPIOA = 0x12, // general purpose i/o port register (write modifies OLAT)
CMD_GPIOB = 0x13,
};
void mcp23018_init(uint8_t addr) {
static uint8_t s_init = 0;
if (!s_init) {
i2c_init();
wait_ms(1000);
s_init = 1;
}
}
bool mcp23018_set_config(uint8_t slave_addr, mcp23018_port_t port, uint8_t conf) {
uint8_t addr = SLAVE_TO_ADDR(slave_addr);
uint8_t cmdDirection = port ? CMD_IODIRB : CMD_IODIRA;
uint8_t cmdPullup = port ? CMD_GPPUB : CMD_GPPUA;
i2c_status_t ret = i2c_write_register(addr, cmdDirection, &conf, sizeof(conf), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_set_config::directionFAILED::%u\n", ret);
return false;
}
ret = i2c_write_register(addr, cmdPullup, &conf, sizeof(conf), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_set_config::pullupFAILED::%u\n", ret);
return false;
}
return true;
}
bool mcp23018_set_output(uint8_t slave_addr, mcp23018_port_t port, uint8_t conf) {
uint8_t addr = SLAVE_TO_ADDR(slave_addr);
uint8_t cmd = port ? CMD_GPIOB : CMD_GPIOA;
i2c_status_t ret = i2c_write_register(addr, cmd, &conf, sizeof(conf), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_set_output::FAILED::%u\n", ret);
return false;
}
return true;
}
bool mcp23018_set_output_all(uint8_t slave_addr, uint8_t confA, uint8_t confB) {
uint8_t addr = SLAVE_TO_ADDR(slave_addr);
uint8_t conf[2] = {confA, confB};
i2c_status_t ret = i2c_write_register(addr, CMD_GPIOA, &conf[0], sizeof(conf), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_set_output::FAILED::%u\n", ret);
return false;
}
return true;
}
bool mcp23018_read_pins(uint8_t slave_addr, mcp23018_port_t port, uint8_t* out) {
uint8_t addr = SLAVE_TO_ADDR(slave_addr);
uint8_t cmd = port ? CMD_GPIOB : CMD_GPIOA;
i2c_status_t ret = i2c_read_register(addr, cmd, out, sizeof(uint8_t), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_read_pins::FAILED::%u\n", ret);
return false;
}
return true;
}
bool mcp23018_read_pins_all(uint8_t slave_addr, uint16_t* out) {
uint8_t addr = SLAVE_TO_ADDR(slave_addr);
typedef union {
uint8_t u8[2];
uint16_t u16;
} data16;
data16 data = {.u16 = 0};
i2c_status_t ret = i2c_read_register(addr, CMD_GPIOA, &data.u8[0], sizeof(data), TIMEOUT);
if (ret != I2C_STATUS_SUCCESS) {
dprintf("mcp23018_read_pins_all::FAILED::%u\n", ret);
return false;
}
*out = data.u16;
return true;
}