pca9554.h

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#pragma once
 
#include "esphome/core/component.h"
#include "esphome/core/hal.h"
#include "esphome/components/i2c/i2c.h"
#include "esphome/components/gpio_expander/cached_gpio_component.h"
#include "esphome/components/gpio_expander/expander_gpio_pin.h"
 
namespace esphome::pca9554 {
 
class PCA9554Component final : public gpio_expander::CachedGpioExpanderComponent<uint16_t, 16>, public i2c::I2CDevice {
 public:
  explicit PCA9554Component(uint8_t pin_count) : pin_count_(pin_count), reg_width_((pin_count + 7) / 8) {}
 
  void setup() override;
  void pin_mode(uint8_t pin, gpio::Flags flags);
 
  void dump_config() override;
 
#ifdef USE_PCA9554_PCAL
  void set_pcal() { this->pcal_ = true; }
  void set_latch(uint8_t pin) { this->latch_ |= 1U << pin; }
  void set_drive_strength(uint8_t pin, uint8_t strength) {
    const uint8_t shift = 2 * pin;
    this->drive_ = (this->drive_ & ~(3UL << shift)) | (uint32_t(strength) << shift);
  }
#endif
 
 protected:
  bool read_inputs_();
  bool write_register_(uint8_t reg, uint16_t value) { return this->write_address_(reg * this->reg_width_, value); }
  bool write_address_(uint8_t address, uint16_t value);
#ifdef USE_PCA9554_PCAL
  bool write_pcal_register_(uint8_t reg, uint16_t value);
  bool write_pcal_shadows_();
  void retry_pcal_shadows_() {
    if (this->pcal_dirty_)
      this->write_pcal_shadows_();
  }
  void update_pcal_register_(uint8_t reg, uint16_t &shadow, uint16_t mask, uint16_t value);
#endif
 
  // Virtual methods from CachedGpioExpander
  bool digital_read_hw(uint8_t pin) override;
  bool digital_read_cache(uint8_t pin) override;
  void digital_write_hw(uint8_t pin, bool value) override;
 
#ifdef USE_PCA9554_PCAL
  uint32_t drive_{0xFFFFFFFF};
#endif
  uint16_t config_mask_{0x00};
  uint16_t output_mask_{0x00};
  uint16_t input_mask_{0x00};
#ifdef USE_PCA9554_PCAL
  // Shadows of the PCAL registers. setup() writes them, so every part starts with the pulls disconnected
  // whatever its power-on state is (the PCAL9555 powers up with pull-ups enabled).
  uint16_t pupd_enable_{0x0000};
  uint16_t pupd_select_{0xFFFF};
  uint16_t latch_{0x0000};
  uint16_t interrupt_mask_{0xFFFF};
#endif
  const uint8_t pin_count_;
  const uint8_t reg_width_;
#ifdef USE_PCA9554_PCAL
  bool pcal_{false};
  bool pcal_dirty_{false};  // a PCAL write failed; retried after the next good read or output write
#endif
};
 
using PCA9554GPIOPin = gpio_expander::ExpanderGPIOPin<PCA9554Component>;
 
}  // namespace esphome::pca9554
 
ESPHOME_EXPANDER_PIN_SUMMARY_DECL(esphome::pca9554::PCA9554Component);