Add sensor support: MAX44009 (#3125)

Co-authored-by: Otto Winter <otto@otto-winter.com>

esphome/components/max44009/max44009.h

@@ -0,0 +1,37 @@
+#pragma once
+
+#include "esphome/components/i2c/i2c.h"
+#include "esphome/components/sensor/sensor.h"
+#include "esphome/core/component.h"
+
+namespace esphome {
+namespace max44009 {
+
+enum MAX44009Mode { MAX44009_MODE_AUTO, MAX44009_MODE_LOW_POWER, MAX44009_MODE_CONTINUOUS };
+
+/// This class implements support for the MAX44009 Illuminance i2c sensor.
+class MAX44009Sensor : public sensor::Sensor, public PollingComponent, public i2c::I2CDevice {
+ public:
+  MAX44009Sensor() {}
+
+  void setup() override;
+  void dump_config() override;
+  float get_setup_priority() const override;
+  void update() override;
+  void set_mode(MAX44009Mode mode);
+  bool set_continuous_mode();
+  bool set_low_power_mode();
+
+ protected:
+  /// Read the illuminance value
+  float read_illuminance_();
+  float convert_to_lux_(uint8_t data_high, uint8_t data_low);
+  uint8_t read_(uint8_t reg);
+  void write_(uint8_t reg, uint8_t value);
+
+  int error_;
+  MAX44009Mode mode_;
+};
+
+}  // namespace max44009
+}  // namespace esphome