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esphome/esphome/components/pcf8574/pcf8574.cpp
J. Nick Koston 784d547294 correctness
2025-09-04 11:19:30 -05:00

117 lines
3.3 KiB
C++

#include "pcf8574.h"
#include "esphome/core/log.h"
namespace esphome {
namespace pcf8574 {
static const char *const TAG = "pcf8574";
void PCF8574Component::setup() {
if (!this->read_gpio_()) {
ESP_LOGE(TAG, "PCF8574 not available under 0x%02X", this->address_);
this->mark_failed();
return;
}
this->write_gpio_();
this->read_gpio_();
}
void PCF8574Component::loop() {
// Invalidate the cache at the start of each loop.
// The actual read will happen on demand in digital_read()
this->cache_valid_ = false;
}
void PCF8574Component::dump_config() {
ESP_LOGCONFIG(TAG, "PCF8574:");
LOG_I2C_DEVICE(this)
ESP_LOGCONFIG(TAG, " Is PCF8575: %s", YESNO(this->pcf8575_));
if (this->is_failed()) {
ESP_LOGE(TAG, ESP_LOG_MSG_COMM_FAIL);
}
}
bool PCF8574Component::digital_read(uint8_t pin) {
// Read the inputs once per loop on demand and cache the result
if (!this->cache_valid_ && this->read_gpio_()) {
this->cache_valid_ = true;
}
return this->input_mask_ & (1 << pin);
}
void PCF8574Component::digital_write(uint8_t pin, bool value) {
if (value) {
this->output_mask_ |= (1 << pin);
} else {
this->output_mask_ &= ~(1 << pin);
}
this->write_gpio_();
}
void PCF8574Component::pin_mode(uint8_t pin, gpio::Flags flags) {
if (flags == gpio::FLAG_INPUT) {
// Clear mode mask bit
this->mode_mask_ &= ~(1 << pin);
// Write GPIO to enable input mode
this->write_gpio_();
} else if (flags == gpio::FLAG_OUTPUT) {
// Set mode mask bit
this->mode_mask_ |= 1 << pin;
}
}
bool PCF8574Component::read_gpio_() {
if (this->is_failed())
return false;
bool success;
uint8_t data[2];
if (this->pcf8575_) {
success = this->read_bytes_raw(data, 2);
this->input_mask_ = (uint16_t(data[1]) << 8) | (uint16_t(data[0]) << 0);
} else {
success = this->read_bytes_raw(data, 1);
this->input_mask_ = data[0];
}
if (!success) {
this->status_set_warning();
return false;
}
this->status_clear_warning();
return true;
}
bool PCF8574Component::write_gpio_() {
if (this->is_failed())
return false;
uint16_t value = 0;
// Pins in OUTPUT mode and where pin is HIGH.
value |= this->mode_mask_ & this->output_mask_;
// Pins in INPUT mode must also be set here
value |= ~this->mode_mask_;
uint8_t data[2];
data[0] = value;
data[1] = value >> 8;
if (this->write(data, this->pcf8575_ ? 2 : 1) != i2c::ERROR_OK) {
this->status_set_warning();
return false;
}
this->status_clear_warning();
return true;
}
float PCF8574Component::get_setup_priority() const { return setup_priority::IO; }
// Run our loop() method early to invalidate cache before any other components access the pins
float PCF8574Component::get_loop_priority() const { return 9.0f; } // Just after WIFI
void PCF8574GPIOPin::setup() { pin_mode(flags_); }
void PCF8574GPIOPin::pin_mode(gpio::Flags flags) { this->parent_->pin_mode(this->pin_, flags); }
bool PCF8574GPIOPin::digital_read() { return this->parent_->digital_read(this->pin_) != this->inverted_; }
void PCF8574GPIOPin::digital_write(bool value) { this->parent_->digital_write(this->pin_, value != this->inverted_); }
std::string PCF8574GPIOPin::dump_summary() const {
char buffer[32];
snprintf(buffer, sizeof(buffer), "%u via PCF8574", pin_);
return buffer;
}
} // namespace pcf8574
} // namespace esphome