Add btd_error_not_connected()
diff --git a/audio/control.c b/audio/control.c
index e710f8f..98b6682 100644
--- a/audio/control.c
+++ b/audio/control.c
@@ -1014,9 +1014,7 @@
 		return NULL;
 
 	if (control->state != AVCTP_STATE_CONNECTED)
-		return g_dbus_create_error(msg,
-					ERROR_INTERFACE ".NotConnected",
-					"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	if (!control->target)
 		return btd_error_not_supported(msg);
@@ -1042,9 +1040,7 @@
 		return NULL;
 
 	if (control->state != AVCTP_STATE_CONNECTED)
-		return g_dbus_create_error(msg,
-					ERROR_INTERFACE ".NotConnected",
-					"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	if (!control->target)
 		return btd_error_not_supported(msg);
diff --git a/audio/device.c b/audio/device.c
index 30ae30d..72c103b 100644
--- a/audio/device.c
+++ b/audio/device.c
@@ -562,8 +562,7 @@
 	struct dev_priv *priv = dev->priv;
 
 	if (priv->state == AUDIO_STATE_DISCONNECTED)
-		return g_dbus_create_error(msg, ERROR_INTERFACE ".NotConnected",
-						"Not connected");
+		return btd_error_not_connected(msg);
 
 	if (priv->dc_req)
 		return dbus_message_new_method_return(msg);
diff --git a/audio/gateway.c b/audio/gateway.c
index 79847b7..93c4301 100644
--- a/audio/gateway.c
+++ b/audio/gateway.c
@@ -423,9 +423,7 @@
 		return NULL;
 
 	if (!gw->rfcomm)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return  btd_error_not_connected(msg);
 
 	gateway_close(device);
 	ba2str(&device->dst, gw_addr);
diff --git a/audio/headset.c b/audio/headset.c
index 0932477..7fc5afb 100644
--- a/audio/headset.c
+++ b/audio/headset.c
@@ -1618,9 +1618,7 @@
 	DBusMessage *reply = NULL;
 
 	if (hs->state < HEADSET_STATE_PLAY_IN_PROGRESS)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	reply = dbus_message_new_method_return(msg);
 	if (!reply)
@@ -1659,9 +1657,7 @@
 	char hs_address[18];
 
 	if (hs->state == HEADSET_STATE_DISCONNECTED)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	headset_shutdown(device);
 	ba2str(&device->dst, hs_address);
@@ -1737,9 +1733,7 @@
 	int err;
 
 	if (hs->state < HEADSET_STATE_CONNECTED)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	reply = dbus_message_new_method_return(msg);
 	if (!reply)
@@ -1774,9 +1768,7 @@
 	DBusMessage *reply = NULL;
 
 	if (hs->state < HEADSET_STATE_CONNECTED)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	reply = dbus_message_new_method_return(msg);
 	if (!reply)
@@ -1808,9 +1800,7 @@
 	switch (hs->state) {
 	case HEADSET_STATE_DISCONNECTED:
 	case HEADSET_STATE_CONNECTING:
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 	case HEADSET_STATE_PLAY_IN_PROGRESS:
 		if (hs->pending && hs->pending->msg == NULL) {
 			hs->pending->msg = dbus_message_ref(msg);
@@ -1901,9 +1891,7 @@
 	int err;
 
 	if (hs->state < HEADSET_STATE_CONNECTED)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	err = headset_set_gain(device, gain, type);
 	if (err < 0)
diff --git a/audio/sink.c b/audio/sink.c
index 1d350c0..e9a529b 100644
--- a/audio/sink.c
+++ b/audio/sink.c
@@ -472,9 +472,7 @@
 	int err;
 
 	if (!sink->session)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	if (sink->connect || sink->disconnect)
 		return g_dbus_create_error(msg, ERROR_INTERFACE ".Failed",
diff --git a/audio/source.c b/audio/source.c
index 8258fcd..75f50ff 100644
--- a/audio/source.c
+++ b/audio/source.c
@@ -423,9 +423,7 @@
 	int err;
 
 	if (!source->session)
-		return g_dbus_create_error(msg, ERROR_INTERFACE
-						".NotConnected",
-						"Device not Connected");
+		return btd_error_not_connected(msg);
 
 	if (source->connect || source->disconnect)
 		return g_dbus_create_error(msg, ERROR_INTERFACE ".Failed",
diff --git a/src/error.c b/src/error.c
index 0ea007a..c8cccf9 100644
--- a/src/error.c
+++ b/src/error.c
@@ -69,3 +69,10 @@
 					".NotSupported",
 					"Operation is not supported");
 }
+
+DBusMessage *btd_error_not_connected(DBusMessage *msg)
+{
+	return g_dbus_create_error(msg, ERROR_INTERFACE
+					".NotConnected",
+					"Not Connected");
+}
diff --git a/src/error.h b/src/error.h
index 71b40d9..7450029 100644
--- a/src/error.h
+++ b/src/error.h
@@ -33,3 +33,4 @@
 DBusMessage *btd_error_invalid_args(DBusMessage *msg);
 DBusMessage *btd_error_already_exists(DBusMessage *msg);
 DBusMessage *btd_error_not_supported(DBusMessage *msg);
+DBusMessage *btd_error_not_connected(DBusMessage *msg);