Fix utility_meter calibration with float values (#35186)

homeassistant/components/utility_meter/sensor.py

@@ -95,7 +95,7 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
 
     platform.async_register_entity_service(
         SERVICE_CALIBRATE_METER,
-        {vol.Required(ATTR_VALUE): vol.Coerce(float)},
+        {vol.Required(ATTR_VALUE): vol.Coerce(Decimal)},
         "async_calibrate",
     )
 
@@ -222,7 +222,7 @@ class UtilityMeterSensor(RestoreEntity):
     async def async_calibrate(self, value):
         """Calibrate the Utility Meter with a given value."""
         _LOGGER.debug("Calibrate %s = %s", self._name, value)
-        self._state = Decimal(value)
+        self._state = value
         self.async_write_ha_state()
 
     async def async_added_to_hass(self):

tests/components/utility_meter/test_sensor.py

@@ -119,6 +119,17 @@ async def test_state(hass):
     assert state is not None
     assert state.state == "100"
 
+    await hass.services.async_call(
+        DOMAIN,
+        SERVICE_CALIBRATE_METER,
+        {ATTR_ENTITY_ID: "sensor.energy_bill_midpeak", ATTR_VALUE: "0.123"},
+        blocking=True,
+    )
+    await hass.async_block_till_done()
+    state = hass.states.get("sensor.energy_bill_midpeak")
+    assert state is not None
+    assert state.state == "0.123"
+
 
 async def test_net_consumption(hass):
     """Test utility sensor state."""