diff --git a/homeassistant/components/smarla/__init__.py b/homeassistant/components/smarla/__init__.py
index 137fcf62b82..d005f0020fb 100644
--- a/homeassistant/components/smarla/__init__.py
+++ b/homeassistant/components/smarla/__init__.py
@@ -7,9 +7,6 @@ from homeassistant.const import CONF_ACCESS_TOKEN
 from homeassistant.core import HomeAssistant
 from homeassistant.exceptions import ConfigEntryAuthFailed, ConfigEntryError
 from homeassistant.helpers import config_validation as cv
-from homeassistant.helpers.device_registry import DeviceInfo
-from homeassistant.helpers.entity import Entity
-from homeassistant.helpers.typing import ConfigType
 
 from .const import DOMAIN, HOST, PLATFORMS
 
@@ -18,11 +15,6 @@ CONFIG_SCHEMA = cv.config_entry_only_config_schema(DOMAIN)
 type FederwiegeConfigEntry = ConfigEntry[Federwiege]
 
 
-async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
-    """Set up this integration using YAML is not supported."""
-    return True
-
-
 async def async_setup_entry(hass: HomeAssistant, entry: FederwiegeConfigEntry) -> bool:
     """Set up this integration using UI."""
     if hass.data.get(DOMAIN) is None:
@@ -68,24 +60,3 @@ async def async_reload_entry(hass: HomeAssistant, entry: ConfigEntry) -> None:
     """Reload config entry."""
     await async_unload_entry(hass, entry)
     await async_setup_entry(hass, entry)
-
-
-class SmarlaBaseEntity(Entity):
-    """Common Base Entity class for defining Smarla device."""
-
-    def __init__(
-        self,
-        federwiege: Federwiege,
-    ) -> None:
-        """Initialise the entity."""
-        super().__init__()
-
-        self._attr_has_entity_name = True
-
-        self._attr_device_info = DeviceInfo(
-            identifiers={(DOMAIN, federwiege.serial_number)},
-            name="Federwiege",
-            model="Smarla",
-            manufacturer="Swing2Sleep",
-            serial_number=federwiege.serial_number,
-        )
diff --git a/homeassistant/components/smarla/config_flow.py b/homeassistant/components/smarla/config_flow.py
index 37eb3900945..fbfe0e9299c 100644
--- a/homeassistant/components/smarla/config_flow.py
+++ b/homeassistant/components/smarla/config_flow.py
@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from typing import Any
+
 from pysmarlaapi import Connection
 import voluptuous as vol
 
@@ -19,7 +21,9 @@ class SmarlaConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
     VERSION = 1
     CONNECTION_CLASS = config_entries.CONN_CLASS_CLOUD_PUSH
 
-    async def async_step_user(self, user_input=None) -> config_entries.ConfigFlowResult:
+    async def async_step_user(
+        self, user_input: dict[str, Any] | None = None
+    ) -> config_entries.ConfigFlowResult:
         """Handle the initial step."""
         if user_input is None:
             return self.async_show_form(
@@ -27,18 +31,20 @@ class SmarlaConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
                 data_schema=STEP_USER_DATA_SCHEMA,
             )
 
-        errors = {}
+        errors: dict[str, str] = {}
 
         try:
             info = await self.validate_input(user_input)
+        except InvalidAuth:
+            errors["base"] = "invalid_auth"
+        except InvalidToken:
+            errors["base"] = "invalid_token"
+
+        if not errors:
             return self.async_create_entry(
                 title=info["title"],
                 data={CONF_ACCESS_TOKEN: info.get(CONF_ACCESS_TOKEN)},
             )
-        except InvalidAuth:
-            errors["base"] = "invalid_auth"
-        except ValueError:
-            errors["base"] = "invalid_token"
 
         return self.async_show_form(
             step_id="user",
@@ -46,12 +52,15 @@ class SmarlaConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
             errors=errors,
         )
 
-    async def validate_input(self, data):
+    async def validate_input(self, data: dict[str, Any]):
         """Validate the user input allows us to connect.
 
         Data has the keys from STEP_USER_DATA_SCHEMA with values provided by the user.
         """
-        conn = Connection(url=HOST, token_b64=data[CONF_ACCESS_TOKEN])
+        try:
+            conn = Connection(url=HOST, token_b64=data[CONF_ACCESS_TOKEN])
+        except ValueError as e:
+            raise InvalidToken from e
 
         await self.async_set_unique_id(conn.token.serialNumber)
         self._abort_if_unique_id_configured()
@@ -67,3 +76,7 @@ class SmarlaConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
 
 class InvalidAuth(exceptions.HomeAssistantError):
     """Error to indicate there is invalid auth."""
+
+
+class InvalidToken(exceptions.HomeAssistantError):
+    """Error to indicate there is an invalid token."""
diff --git a/homeassistant/components/smarla/entity.py b/homeassistant/components/smarla/entity.py
new file mode 100644
index 00000000000..fb28d55bdf2
--- /dev/null
+++ b/homeassistant/components/smarla/entity.py
@@ -0,0 +1,29 @@
+"""Common base for entities."""
+
+from pysmarlaapi import Federwiege
+
+from homeassistant.helpers.device_registry import DeviceInfo
+from homeassistant.helpers.entity import Entity
+
+from .const import DOMAIN
+
+
+class SmarlaBaseEntity(Entity):
+    """Common Base Entity class for defining Smarla device."""
+
+    def __init__(
+        self,
+        federwiege: Federwiege,
+    ) -> None:
+        """Initialise the entity."""
+        super().__init__()
+
+        self._attr_has_entity_name = True
+
+        self._attr_device_info = DeviceInfo(
+            identifiers={(DOMAIN, federwiege.serial_number)},
+            name="Federwiege",
+            model="Smarla",
+            manufacturer="Swing2Sleep",
+            serial_number=federwiege.serial_number,
+        )
diff --git a/homeassistant/components/smarla/number.py b/homeassistant/components/smarla/number.py
index a177759f3bc..8f8d2ec82c2 100644
--- a/homeassistant/components/smarla/number.py
+++ b/homeassistant/components/smarla/number.py
@@ -1,6 +1,7 @@
 """Support for the Swing2Sleep Smarla number entities."""
 
 from dataclasses import dataclass
+from typing import Any
 
 from pysmarlaapi import Federwiege
 
@@ -12,7 +13,8 @@ from homeassistant.components.number import (
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 
-from . import FederwiegeConfigEntry, SmarlaBaseEntity
+from . import FederwiegeConfigEntry
+from .entity import SmarlaBaseEntity
 
 
 @dataclass(frozen=True, kw_only=True)
@@ -45,7 +47,7 @@ async def async_setup_entry(
     """Set up the Smarla numbers from config entry."""
     federwiege = config_entry.runtime_data
 
-    entities: list[SmarlaNumber] = []
+    entities: list[NumberEntity] = []
 
     for desc in NUMBER_TYPES:
         entity = SmarlaNumber(federwiege, desc)
@@ -57,7 +59,7 @@ async def async_setup_entry(
 class SmarlaNumber(SmarlaBaseEntity, NumberEntity):
     """Representation of Smarla number."""
 
-    async def on_change(self, value):
+    async def on_change(self, value: Any):
         """Notify ha when state changes."""
         self.async_write_ha_state()
 
diff --git a/homeassistant/components/smarla/sensor.py b/homeassistant/components/smarla/sensor.py
index 35041748eec..1af4aa04a22 100644
--- a/homeassistant/components/smarla/sensor.py
+++ b/homeassistant/components/smarla/sensor.py
@@ -1,6 +1,7 @@
 """Support for the Swing2Sleep Smarla sensor entities."""
 
 from dataclasses import dataclass
+from typing import Any
 
 from pysmarlaapi import Federwiege
 
@@ -13,7 +14,8 @@ from homeassistant.const import UnitOfLength, UnitOfTime
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 
-from . import FederwiegeConfigEntry, SmarlaBaseEntity
+from . import FederwiegeConfigEntry
+from .entity import SmarlaBaseEntity
 
 
 @dataclass(frozen=True, kw_only=True)
@@ -72,7 +74,7 @@ async def async_setup_entry(
     """Set up the Smarla sensors from config entry."""
     federwiege = config_entry.runtime_data
 
-    entities: list[SmarlaSensor] = []
+    entities: list[SensorEntity] = []
 
     for desc in NUMBER_TYPES:
         entity = SmarlaSensor(federwiege, desc)
@@ -84,7 +86,7 @@ async def async_setup_entry(
 class SmarlaSensor(SmarlaBaseEntity, SensorEntity):
     """Representation of Smarla sensor."""
 
-    async def on_change(self, value):
+    async def on_change(self, value: Any):
         """Notify ha when state changes."""
         self.async_write_ha_state()
 
diff --git a/homeassistant/components/smarla/switch.py b/homeassistant/components/smarla/switch.py
index 1397ee33581..9eeb4008ff6 100644
--- a/homeassistant/components/smarla/switch.py
+++ b/homeassistant/components/smarla/switch.py
@@ -9,7 +9,8 @@ from homeassistant.components.switch import SwitchEntity, SwitchEntityDescriptio
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 
-from . import FederwiegeConfigEntry, SmarlaBaseEntity
+from . import FederwiegeConfigEntry
+from .entity import SmarlaBaseEntity
 
 
 @dataclass(frozen=True, kw_only=True)
@@ -44,7 +45,7 @@ async def async_setup_entry(
     """Set up the Smarla switches from config entry."""
     federwiege = config_entry.runtime_data
 
-    entities: list[SmarlaSwitch] = []
+    entities: list[SwitchEntity] = []
 
     for desc in NUMBER_TYPES:
         entity = SmarlaSwitch(federwiege, desc)
@@ -56,7 +57,7 @@ async def async_setup_entry(
 class SmarlaSwitch(SmarlaBaseEntity, SwitchEntity):
     """Representation of Smarla switch."""
 
-    async def on_change(self, value):
+    async def on_change(self, value: Any):
         """Notify ha when state changes."""
         self.async_write_ha_state()