diff --git a/.coveragerc b/.coveragerc
index 6416ad3e2b4..0f9904d80a2 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -94,7 +94,6 @@ omit =
     homeassistant/components/camera/generic.py
     homeassistant/components/camera/mjpeg.py
     homeassistant/components/camera/rpi_camera.py
-    homeassistant/components/cec.py
     homeassistant/components/device_tracker/actiontec.py
     homeassistant/components/device_tracker/aruba.py
     homeassistant/components/device_tracker/asuswrt.py
@@ -115,6 +114,7 @@ omit =
     homeassistant/components/downloader.py
     homeassistant/components/feedreader.py
     homeassistant/components/garage_door/wink.py
+    homeassistant/components/hdmi_cec.py
     homeassistant/components/ifttt.py
     homeassistant/components/keyboard.py
     homeassistant/components/light/blinksticklight.py
diff --git a/homeassistant/components/hdmi_cec.py b/homeassistant/components/hdmi_cec.py
index f5a64b909af..89cbe789c58 100644
--- a/homeassistant/components/hdmi_cec.py
+++ b/homeassistant/components/hdmi_cec.py
@@ -32,7 +32,7 @@ CONFIG_SCHEMA = vol.Schema({
     DOMAIN: vol.Schema({
         vol.Required(CONF_DEVICES): DEVICE_SCHEMA
     })
-})
+}, extra=vol.ALLOW_EXTRA)
 
 
 def parse_mapping(mapping, parents=None):
@@ -68,7 +68,7 @@ def setup(hass, config):
     # to physical address represented as a list of
     # four elements.
     flat = {}
-    for pair in parse_mapping(config[DOMAIN][0].get(CONF_DEVICES, {})):
+    for pair in parse_mapping(config[DOMAIN].get(CONF_DEVICES, {})):
         flat[pair[0]] = pad_physical_address(pair[1])
 
     # Configure libcec.