Allow "slave" parameter in modbus service calls (#66874)

* Allow "slave" parameter in modbus service calls.

homeassistant/components/modbus/const.py

@@ -69,6 +69,7 @@ UDP = "udp"
 ATTR_ADDRESS = "address"
 ATTR_HUB = "hub"
 ATTR_UNIT = "unit"
+ATTR_SLAVE = "slave"
 ATTR_VALUE = "value"
 ATTR_STATE = "state"
 ATTR_TEMPERATURE = "temperature"

homeassistant/components/modbus/modbus.py

@@ -39,6 +39,7 @@ from homeassistant.helpers.typing import ConfigType
 from .const import (
     ATTR_ADDRESS,
     ATTR_HUB,
+    ATTR_SLAVE,
     ATTR_STATE,
     ATTR_UNIT,
     ATTR_VALUE,
@@ -156,7 +157,11 @@ async def async_modbus_setup(
 
     async def async_write_register(service: ServiceCall) -> None:
         """Write Modbus registers."""
-        unit = int(float(service.data[ATTR_UNIT]))
+        unit = 0
+        if ATTR_UNIT in service.data:
+            unit = int(float(service.data[ATTR_UNIT]))
+        if ATTR_SLAVE in service.data:
+            unit = int(float(service.data[ATTR_SLAVE]))
         address = int(float(service.data[ATTR_ADDRESS]))
         value = service.data[ATTR_VALUE]
         hub = hub_collect[
@@ -173,7 +178,11 @@ async def async_modbus_setup(
 
     async def async_write_coil(service: ServiceCall) -> None:
         """Write Modbus coil."""
-        unit = service.data[ATTR_UNIT]
+        unit = 0
+        if ATTR_UNIT in service.data:
+            unit = int(float(service.data[ATTR_UNIT]))
+        if ATTR_SLAVE in service.data:
+            unit = int(float(service.data[ATTR_SLAVE]))
         address = service.data[ATTR_ADDRESS]
         state = service.data[ATTR_STATE]
         hub = hub_collect[
@@ -195,7 +204,8 @@ async def async_modbus_setup(
             schema=vol.Schema(
                 {
                     vol.Optional(ATTR_HUB, default=DEFAULT_HUB): cv.string,
-                    vol.Required(ATTR_UNIT): cv.positive_int,
+                    vol.Exclusive(ATTR_SLAVE, "unit"): cv.positive_int,
+                    vol.Exclusive(ATTR_UNIT, "unit"): cv.positive_int,
                     vol.Required(ATTR_ADDRESS): cv.positive_int,
                     vol.Required(x_write[2]): vol.Any(
                         cv.positive_int, vol.All(cv.ensure_list, [x_write[3]])

homeassistant/components/modbus/services.yaml

@@ -14,13 +14,13 @@ write_coil:
       name: State
       description: State to write.
       required: true
-      example: false
+      example: "0 or [1,0]"
       selector:
         object:
-    unit:
+    slave:
-      name: Unit
+      name: Slave
-      description: Address of the modbus unit.
+      description: Address of the modbus unit/slave.
-      required: true
+      required: false
       selector:
         number:
           min: 1
@@ -44,10 +44,10 @@ write_register:
         number:
           min: 0
           max: 65535
-    unit:
+    slave:
-      name: Unit
+      name: Slave
-      description: Address of the modbus unit.
+      description: Address of the modbus unit/slave.
-      required: true
+      required: false
       selector:
         number:
           min: 1

tests/components/modbus/test_init.py

@@ -25,6 +25,7 @@ from homeassistant.components.binary_sensor import DOMAIN as BINARY_SENSOR_DOMAI
 from homeassistant.components.modbus.const import (
     ATTR_ADDRESS,
     ATTR_HUB,
+    ATTR_SLAVE,
     ATTR_STATE,
     ATTR_UNIT,
     ATTR_VALUE,
@@ -484,8 +485,15 @@ SERVICE = "service"
         {VALUE: ModbusException("fail write_"), DATA: "Pymodbus:"},
     ],
 )
+@pytest.mark.parametrize(
+    "do_unit",
+    [
+        ATTR_UNIT,
+        ATTR_SLAVE,
+    ],
+)
 async def test_pb_service_write(
-    hass, do_write, do_return, caplog, mock_modbus_with_pymodbus
+    hass, do_write, do_return, do_unit, caplog, mock_modbus_with_pymodbus
 ):
     """Run test for service write_register."""
 
@@ -498,7 +506,7 @@ async def test_pb_service_write(
 
     data = {
         ATTR_HUB: TEST_MODBUS_NAME,
-        ATTR_UNIT: 17,
+        do_unit: 17,
         ATTR_ADDRESS: 16,
         do_write[DATA]: do_write[VALUE],
     }