diff --git a/homeassistant/components/dormakaba_dkey/binary_sensor.py b/homeassistant/components/dormakaba_dkey/binary_sensor.py
index 2ec2b0a1c91..1c2205c01d3 100644
--- a/homeassistant/components/dormakaba_dkey/binary_sensor.py
+++ b/homeassistant/components/dormakaba_dkey/binary_sensor.py
@@ -22,20 +22,13 @@ from .entity import DormakabaDkeyEntity
 from .models import DormakabaDkeyData
 
 
-@dataclass(frozen=True)
-class DormakabaDkeyBinarySensorDescriptionMixin:
-    """Class for keys required by Dormakaba dKey binary sensor entity."""
+@dataclass(frozen=True, kw_only=True)
+class DormakabaDkeyBinarySensorDescription(BinarySensorEntityDescription):
+    """Describes Dormakaba dKey binary sensor entity."""
 
     is_on: Callable[[Notifications], bool]
 
 
-@dataclass(frozen=True)
-class DormakabaDkeyBinarySensorDescription(
-    BinarySensorEntityDescription, DormakabaDkeyBinarySensorDescriptionMixin
-):
-    """Describes Dormakaba dKey binary sensor entity."""
-
-
 BINARY_SENSOR_DESCRIPTIONS = (
     DormakabaDkeyBinarySensorDescription(
         key="door_position",