Add Pca9554 component (#4192)

esphome/components/pca9554/pca9554.h

@@ -0,0 +1,64 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/core/hal.h"
+#include "esphome/components/i2c/i2c.h"
+
+namespace esphome {
+namespace pca9554 {
+
+class PCA9554Component : public Component, public i2c::I2CDevice {
+ public:
+  PCA9554Component() = default;
+
+  /// Check i2c availability and setup masks
+  void setup() override;
+  /// Helper function to read the value of a pin.
+  bool digital_read(uint8_t pin);
+  /// Helper function to write the value of a pin.
+  void digital_write(uint8_t pin, bool value);
+  /// Helper function to set the pin mode of a pin.
+  void pin_mode(uint8_t pin, gpio::Flags flags);
+
+  float get_setup_priority() const override;
+
+  void dump_config() override;
+
+ protected:
+  bool read_inputs_();
+
+  bool write_register_(uint8_t reg, uint8_t value);
+
+  /// Mask for the pin config - 1 means OUTPUT, 0 means INPUT
+  uint8_t config_mask_{0x00};
+  /// The mask to write as output state - 1 means HIGH, 0 means LOW
+  uint8_t output_mask_{0x00};
+  /// The state of the actual input pin states - 1 means HIGH, 0 means LOW
+  uint8_t input_mask_{0x00};
+  /// Storage for last I2C error seen
+  esphome::i2c::ErrorCode last_error_;
+};
+
+/// Helper class to expose a PCA9554 pin as an internal input GPIO pin.
+class PCA9554GPIOPin : public GPIOPin {
+ public:
+  void setup() override;
+  void pin_mode(gpio::Flags flags) override;
+  bool digital_read() override;
+  void digital_write(bool value) override;
+  std::string dump_summary() const override;
+
+  void set_parent(PCA9554Component *parent) { parent_ = parent; }
+  void set_pin(uint8_t pin) { pin_ = pin; }
+  void set_inverted(bool inverted) { inverted_ = inverted; }
+  void set_flags(gpio::Flags flags) { flags_ = flags; }
+
+ protected:
+  PCA9554Component *parent_;
+  uint8_t pin_;
+  bool inverted_;
+  gpio::Flags flags_;
+};
+
+}  // namespace pca9554
+}  // namespace esphome