diff --git a/homeassistant/components/nest/legacy/binary_sensor.py b/homeassistant/components/nest/legacy/binary_sensor.py
index 8b17e7d020f..5c412b86dbd 100644
--- a/homeassistant/components/nest/legacy/binary_sensor.py
+++ b/homeassistant/components/nest/legacy/binary_sensor.py
@@ -8,7 +8,10 @@ from homeassistant.components.binary_sensor import (
     BinarySensorDeviceClass,
     BinarySensorEntity,
 )
+from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_BINARY_SENSORS, CONF_MONITORED_CONDITIONS
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from . import NestSensorDevice
 from .const import DATA_NEST, DATA_NEST_CONFIG
@@ -53,14 +56,9 @@ _VALID_BINARY_SENSOR_TYPES = {
 }
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
-    """Set up the Nest binary sensors.
-
-    No longer used.
-    """
-
-
-async def async_setup_legacy_entry(hass, entry, async_add_entities) -> None:
+async def async_setup_legacy_entry(
+    hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
+) -> None:
     """Set up a Nest binary sensor based on a config entry."""
     nest = hass.data[DATA_NEST]
 
diff --git a/homeassistant/components/nest/legacy/camera.py b/homeassistant/components/nest/legacy/camera.py
index d118b9b8c4a..e74f23aeaf6 100644
--- a/homeassistant/components/nest/legacy/camera.py
+++ b/homeassistant/components/nest/legacy/camera.py
@@ -9,7 +9,10 @@ import logging
 import requests
 
 from homeassistant.components.camera import PLATFORM_SCHEMA, Camera, CameraEntityFeature
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity import DeviceInfo
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.util.dt import utcnow
 
 from .const import DATA_NEST, DOMAIN
@@ -21,14 +24,9 @@ NEST_BRAND = "Nest"
 PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend({})
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
-    """Set up a Nest Cam.
-
-    No longer in use.
-    """
-
-
-async def async_setup_legacy_entry(hass, entry, async_add_entities) -> None:
+async def async_setup_legacy_entry(
+    hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
+) -> None:
     """Set up a Nest sensor based on a config entry."""
     camera_devices = await hass.async_add_executor_job(hass.data[DATA_NEST].cameras)
     cameras = [NestCamera(structure, device) for structure, device in camera_devices]
diff --git a/homeassistant/components/nest/legacy/climate.py b/homeassistant/components/nest/legacy/climate.py
index 5f066e3bc0e..323633e0ee3 100644
--- a/homeassistant/components/nest/legacy/climate.py
+++ b/homeassistant/components/nest/legacy/climate.py
@@ -20,9 +20,12 @@ from homeassistant.components.climate import (
     HVACAction,
     HVACMode,
 )
+from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import ATTR_TEMPERATURE, CONF_SCAN_INTERVAL, UnitOfTemperature
+from homeassistant.core import HomeAssistant
 from homeassistant.helpers.dispatcher import async_dispatcher_connect
 from homeassistant.helpers.entity import DeviceInfo
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from .const import DATA_NEST, DOMAIN, SIGNAL_NEST_UPDATE
 
@@ -58,14 +61,9 @@ PRESET_AWAY_AND_ECO = "Away and Eco"
 PRESET_MODES = [PRESET_NONE, PRESET_AWAY, PRESET_ECO, PRESET_AWAY_AND_ECO]
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
-    """Set up the Nest thermostat.
-
-    No longer in use.
-    """
-
-
-async def async_setup_legacy_entry(hass, entry, async_add_entities) -> None:
+async def async_setup_legacy_entry(
+    hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
+) -> None:
     """Set up the Nest climate device based on a config entry."""
     temp_unit = hass.config.units.temperature_unit
 
diff --git a/homeassistant/components/nest/legacy/sensor.py b/homeassistant/components/nest/legacy/sensor.py
index ce38b2dbf0d..e4061df1a75 100644
--- a/homeassistant/components/nest/legacy/sensor.py
+++ b/homeassistant/components/nest/legacy/sensor.py
@@ -8,6 +8,7 @@ from homeassistant.components.sensor import (
     SensorEntity,
     SensorStateClass,
 )
+from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import (
     CONF_MONITORED_CONDITIONS,
     CONF_SENSORS,
@@ -15,6 +16,8 @@ from homeassistant.const import (
     STATE_OFF,
     UnitOfTemperature,
 )
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from . import NestSensorDevice
 from .const import DATA_NEST, DATA_NEST_CONFIG
@@ -75,14 +78,9 @@ _SENSOR_TYPES_DEPRECATED = SENSOR_TYPES_DEPRECATED + DEPRECATED_WEATHER_VARS
 _LOGGER = logging.getLogger(__name__)
 
 
-def setup_platform(hass, config, add_entities, discovery_info=None):
-    """Set up the Nest Sensor.
-
-    No longer used.
-    """
-
-
-async def async_setup_legacy_entry(hass, entry, async_add_entities) -> None:
+async def async_setup_legacy_entry(
+    hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
+) -> None:
     """Set up a Nest sensor based on a config entry."""
     nest = hass.data[DATA_NEST]