Allow mqtt device_class or UOM to be None (#26973)

source/_integrations/binary_sensor.mqtt.markdown

@@ -114,7 +114,8 @@ device:
       required: false
       type: string
 device_class:
-  description: Sets the [class of the device](/integrations/binary_sensor/#device-class), changing the device state and icon that is displayed on the frontend.
+  description: Sets the [class of the device](/integrations/binary_sensor/#device-class), changing the device state and icon that is displayed on the frontend. The `device_class` can be `null`.
+  default: None
   required: false
   type: string
 enabled_by_default:

source/_integrations/button.mqtt.markdown

@@ -112,8 +112,9 @@ device:
       required: false
       type: string
 device_class:
-  description: The [type/class](/integrations/button/#device-class) of the button to set the icon in the frontend.
+  description: The [type/class](/integrations/button/#device-class) of the button to set the icon in the frontend. The `device_class` can be `null`.
   required: false
+  default: None
   type: device_class
   default: None
 enabled_by_default:

source/_integrations/cover.mqtt.markdown

@@ -125,7 +125,8 @@ device:
       required: false
       type: string
 device_class:
-  description: Sets the [class of the device](/integrations/cover/), changing the device state and icon that is displayed on the frontend.
+  description: Sets the [class of the device](/integrations/cover/), changing the device state and icon that is displayed on the frontend. The `device_class` can be `null`.
+  default: None
   required: false
   type: string
 enabled_by_default:

source/_integrations/humidifier.mqtt.markdown

@@ -121,7 +121,7 @@ device:
       required: false
       type: string
 device_class:
-  description: The device class of the MQTT device. Must be either `humidifier` or `dehumidifier`.
+  description: The device class of the MQTT device. Must be either `humidifier`, `dehumidifier` or `null`.
   required: false
   type: string
   default: humidifier

source/_integrations/number.mqtt.markdown

@@ -106,7 +106,8 @@ device:
       required: false
       type: string
 device_class:
-  description: The [type/class](/integrations/number/#device-class) of the number.
+  description: The [type/class](/integrations/number/#device-class) of the number. The `device_class` can be `null`.
+  default: None
   required: false
   type: device_class
   default: None
@@ -194,7 +195,8 @@ unique_id:
   required: false
   type: string
 unit_of_measurement:
-  description: Defines the unit of measurement of the sensor, if any.
+  description: Defines the unit of measurement of the sensor, if any. The `unit_of_measurement` can be `null`.
+  Default: None
   required: false
   type: string
 value_template:

source/_integrations/sensor.mqtt.markdown

@@ -106,7 +106,8 @@ device:
       required: false
       type: string
 device_class:
-  description: The [type/class](/integrations/sensor/#device-class) of the sensor to set the icon in the frontend.
+  description: The [type/class](/integrations/sensor/#device-class) of the sensor to set the icon in the frontend. The `device_class` can be `null`.
+  default: None
   required: false
   type: device_class
   default: None
@@ -185,7 +186,8 @@ state_class:
   type: string
   default: None
 state_topic:
-  description: The MQTT topic subscribed to receive sensor values. If `device_class`, `state_class`, `unit_of_measurement` or `suggested_display_precision` is set, and a numeric value is expected, an empty value `''` will be ignored and will not update the state, a `'None'` value will set the sensor to an `unknown` state.
+  description: The MQTT topic subscribed to receive sensor values. If `device_class`, `state_class`, `unit_of_measurement` or `suggested_display_precision` is set, and a numeric value is expected, an empty value `''` will be ignored and will not update the state, a `'null'` value will set the sensor to an `unknown` state. The `device_class` can be `null`.
+  default: None
   required: true
   type: string
 unique_id:
@@ -193,7 +195,8 @@ unique_id:
   required: false
   type: string
 unit_of_measurement:
-  description: Defines the units of measurement of the sensor, if any.
+  description: Defines the units of measurement of the sensor, if any. The `unit_of_measurement` can be `null`.
+  default: None
   required: false
   type: string
 value_template:

source/_integrations/switch.mqtt.markdown

@@ -116,7 +116,7 @@ device:
       required: false
       type: string
 device_class:
-  description: The [type/class](/integrations/switch/#device-class) of the switch to set the icon in the frontend.
+  description: The [type/class](/integrations/switch/#device-class) of the switch to set the icon in the frontend. The `device_class` can be `null`.
   required: false
   type: device_class
   default: None

source/_integrations/update.mqtt.markdown

@@ -109,7 +109,8 @@ device:
       required: false
       type: string
 device_class:
-  description: The [type/class](/integrations/update/#device-classes) of the update to set the icon in the frontend.
+  description: The [type/class](/integrations/update/#device-classes) of the update to set the icon in the frontend. The `device_class` can be `null`.
+  default: None
   required: false
   type: device_class
   default: None