Commit 8a5926b5 authored by Woazboat's avatar Woazboat Committed by Florian Kargl
Browse files

refactor(portexpander): defines for portexpander commands + common read/write functions

parent b4c64ba8
......@@ -7,17 +7,57 @@
#include <string.h>
#include <stdbool.h>
// PCAL6408A I2C port expander
static bool detected = false;
static uint8_t output_state;
/* clang-format off */
#define PE_ADDR 0x42
#define PE_C_INPUT_PORT 0x00
#define PE_C_OUTPUT_PORT 0x01
#define PE_C_POLARITY_INV 0x02
#define PE_C_CONFIG 0x03
#define PE_C_OUTPUT_DRIVE_STR_0 0x40
#define PE_C_OUTPUT_DRIVE_STR_1 0x41
#define PE_C_INPUT_LATCH 0x42
#define PE_C_PULL_ENABLE 0x43
#define PE_C_PULL_SEL 0x44
#define PE_C_INT_MASK 0x45
#define PE_C_INT_STATUS 0x46
#define PE_C_OUTPUT_PORT_CONFIG 0x4F
#define PE_CONFIG_OUT 0
#define PE_CONFIG_IN 1
#define PE_PULL_DOWN 0
#define PE_PULL_UP 1
#define PE_OUT_PUSH_PULL 0
#define PE_OUT_OPEN_DRAIN 1
/* clang-format on */
#define PE_INPUT_MASK ((uint8_t)0b01101000) // 3, 5, 6 = input
static int portexpander_write(uint8_t command, uint8_t data)
{
uint8_t i2c_data[2] = { command, data };
return I2C_MasterWrite(MXC_I2C1_BUS0, PE_ADDR, i2c_data, 2, 0);
}
static int portexpander_read(uint8_t command, uint8_t *data)
{
I2C_MasterWrite(MXC_I2C1_BUS0, PE_ADDR, &command, 1, 1);
return I2C_MasterRead(MXC_I2C1_BUS0, PE_ADDR, data, 1, 0);
}
void portexpander_init(void)
{
uint8_t addr = 0x21;
int ret;
// Enable pull-ups for buttons
uint8_t command[] = { 0x43, 0x68 };
ret = I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
// Enable pull-ups for buttons (type defaults to pull-up)
ret = portexpander_write(PE_C_PULL_ENABLE, PE_INPUT_MASK);
if (ret != 2) {
printf("portexpander NOT detected\n");
......@@ -27,31 +67,22 @@ void portexpander_init(void)
detected = true;
// Set _all_ outputs to open-drain to support the high side p-channel transistors.
command[0] = 0x4F;
command[1] = 0x01;
I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
portexpander_write(PE_C_OUTPUT_PORT_CONFIG, PE_OUT_OPEN_DRAIN);
// Enable outputs for the transistors, the LED and the LCD reset
command[0] = 0x03;
command[1] = 0x68;
I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
portexpander_write(PE_C_CONFIG, PE_INPUT_MASK);
// Set outputs to high (i.e. open-drain)
output_state = 0x97;
command[0] = 0x01;
command[1] = output_state;
I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
output_state = ~PE_INPUT_MASK;
portexpander_write(PE_C_OUTPUT_PORT, output_state);
}
uint8_t portexpander_get(void)
{
uint8_t addr = 0x21;
uint8_t command[] = { 0x00 };
uint8_t buf = 0xFF;
uint8_t buf = 0xFF;
if (detected) {
I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 1, 1);
I2C_MasterRead(MXC_I2C1_BUS0, addr << 1, &buf, 1, 0);
portexpander_read(PE_C_INPUT_PORT, &buf);
}
return buf;
......@@ -64,9 +95,6 @@ bool portexpander_detected(void)
void portexpander_set(uint8_t pin, uint8_t value)
{
uint8_t addr = 0x21;
uint8_t command[2];
if (detected && pin < 8) {
if (value) {
output_state |= (1 << pin);
......@@ -74,8 +102,6 @@ void portexpander_set(uint8_t pin, uint8_t value)
output_state &= ~(1 << pin);
}
command[0] = 0x01;
command[1] = output_state;
I2C_MasterWrite(MXC_I2C1_BUS0, addr << 1, command, 2, 0);
portexpander_write(PE_C_OUTPUT_PORT, output_state);
}
}
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