Modbus: make delay configurable

Add optional parameter "delay" to Modbus configuration

Default is 0, which means do not execute time.sleep

homeassistant/components/modbus/__init__.py

@@ -9,6 +9,7 @@
 
 from homeassistant.const import (
     ATTR_STATE,
+    CONF_DELAY,
     CONF_HOST,
     CONF_METHOD,
     CONF_NAME,
@@ -60,6 +61,7 @@
         vol.Required(CONF_PORT): cv.port,
         vol.Required(CONF_TYPE): vol.Any("tcp", "udp", "rtuovertcp"),
         vol.Optional(CONF_TIMEOUT, default=3): cv.socket_timeout,
+        vol.Optional(CONF_DELAY, default=0): cv.positive_int,
     }
 )
 
@@ -132,7 +134,8 @@ def setup(hass, config):
     for client_config in config[DOMAIN]:
         client = setup_client(client_config)
         name = client_config[CONF_NAME]
-        hub_collect[name] = ModbusHub(client, name)
+        delay = client_config[CONF_DELAY]
+        hub_collect[name] = ModbusHub(client, name, delay)
         _LOGGER.debug("Setting up hub: %s", client_config)
 
     def stop_modbus(event):
@@ -187,11 +190,12 @@ def write_coil(service):
 class ModbusHub:
     """Thread safe wrapper class for pymodbus."""
 
-    def __init__(self, modbus_client, name):
+    def __init__(self, modbus_client, name, delay):
         """Initialize the Modbus hub."""
         self._client = modbus_client
         self._lock = threading.Lock()
         self._name = name
+        self._delay = delay
 
     @property
     def name(self):
@@ -207,7 +211,8 @@ def connect(self):
         """Connect client."""
         with self._lock:
             self._client.connect()
-            time.sleep(2)
+            if self._delay > 0:
+                time.sleep(self._delay)
 
     def read_coils(self, unit, address, count):
         """Read coils."""