diff --git a/src/error.c b/src/error.c
index dd85cd288..29c071067 100644
--- a/src/error.c
+++ b/src/error.c
@@ -14,6 +14,8 @@
 #include <config.h>
 #endif
 
+#include <errno.h>
+#include <stdio.h>
 #include "gdbus/gdbus.h"
 
 #include "error.h"
@@ -66,12 +68,24 @@ DBusMessage *btd_error_in_progress(DBusMessage *msg)
 					"In Progress");
 }
 
+DBusMessage *btd_error_in_progress_str(DBusMessage *msg, const char *str)
+{
+	return g_dbus_create_error(msg, ERROR_INTERFACE ".InProgress",
+					"%s", str);
+}
+
 DBusMessage *btd_error_not_available(DBusMessage *msg)
 {
 	return g_dbus_create_error(msg, ERROR_INTERFACE ".NotAvailable",
 					"Operation currently not available");
 }
 
+DBusMessage *btd_error_not_available_str(DBusMessage *msg, const char *str)
+{
+	return g_dbus_create_error(msg, ERROR_INTERFACE ".NotAvailable",
+					"%s", str);
+}
+
 DBusMessage *btd_error_does_not_exist(DBusMessage *msg)
 {
 	return g_dbus_create_error(msg, ERROR_INTERFACE ".DoesNotExist",
@@ -108,8 +122,94 @@ DBusMessage *btd_error_not_ready(DBusMessage *msg)
 					"Resource Not Ready");
 }
 
+DBusMessage *btd_error_not_ready_str(DBusMessage *msg, const char *str)
+{
+	return g_dbus_create_error(msg, ERROR_INTERFACE ".NotReady",
+					"%s", str);
+}
+
 DBusMessage *btd_error_failed(DBusMessage *msg, const char *str)
 {
 	return g_dbus_create_error(msg, ERROR_INTERFACE
 					".Failed", "%s", str);
 }
+
+const char *btd_error_bredr_conn_from_errno(int errno_code)
+{
+	switch (-errno_code) {
+	case EALREADY:
+	case EISCONN:
+		return ERR_BREDR_CONN_ALREADY_CONNECTED;
+	case EHOSTDOWN:
+		return ERR_BREDR_CONN_PAGE_TIMEOUT;
+	case ENOPROTOOPT:
+		return ERR_BREDR_CONN_PROFILE_UNAVAILABLE;
+	case EIO:
+		return ERR_BREDR_CONN_CREATE_SOCKET;
+	case EINVAL:
+		return ERR_BREDR_CONN_INVALID_ARGUMENTS;
+	case EHOSTUNREACH:
+		return ERR_BREDR_CONN_ADAPTER_NOT_POWERED;
+	case EOPNOTSUPP:
+	case EPROTONOSUPPORT:
+		return ERR_BREDR_CONN_NOT_SUPPORTED;
+	case EBADFD:
+		return ERR_BREDR_CONN_BAD_SOCKET;
+	case ENOMEM:
+		return ERR_BREDR_CONN_MEMORY_ALLOC;
+	case EBUSY:
+		return ERR_BREDR_CONN_BUSY;
+	case EMLINK:
+		return ERR_BREDR_CONN_CNCR_CONNECT_LIMIT;
+	case ETIMEDOUT:
+		return ERR_BREDR_CONN_TIMEOUT;
+	case ECONNREFUSED:
+		return ERR_BREDR_CONN_REFUSED;
+	case ECONNRESET:
+		return ERR_BREDR_CONN_ABORT_BY_REMOTE;
+	case ECONNABORTED:
+		return ERR_BREDR_CONN_ABORT_BY_LOCAL;
+	case EPROTO:
+		return ERR_BREDR_CONN_LMP_PROTO_ERROR;
+	default:
+		return ERR_BREDR_CONN_UNKNOWN;
+	}
+}
+
+const char *btd_error_le_conn_from_errno(int errno_code)
+{
+	switch (-errno_code) {
+	case EINVAL:
+		return ERR_LE_CONN_INVALID_ARGUMENTS;
+	case EHOSTUNREACH:
+		return ERR_LE_CONN_ADAPTER_NOT_POWERED;
+	case EOPNOTSUPP:
+	case EPROTONOSUPPORT:
+		return ERR_LE_CONN_NOT_SUPPORTED;
+	case EALREADY:
+	case EISCONN:
+		return ERR_LE_CONN_ALREADY_CONNECTED;
+	case EBADFD:
+		return ERR_LE_CONN_BAD_SOCKET;
+	case ENOMEM:
+		return ERR_LE_CONN_MEMORY_ALLOC;
+	case EBUSY:
+		return ERR_LE_CONN_BUSY;
+	case ECONNREFUSED:
+		return ERR_LE_CONN_REFUSED;
+	case EIO:
+		return ERR_LE_CONN_CREATE_SOCKET;
+	case ETIMEDOUT:
+		return ERR_LE_CONN_TIMEOUT;
+	case EMLINK:
+		return ERR_LE_CONN_SYNC_CONNECT_LIMIT;
+	case ECONNRESET:
+		return ERR_LE_CONN_ABORT_BY_REMOTE;
+	case ECONNABORTED:
+		return ERR_LE_CONN_ABORT_BY_LOCAL;
+	case EPROTO:
+		return ERR_LE_CONN_LL_PROTO_ERROR;
+	default:
+		return ERR_LE_CONN_UNKNOWN;
+	}
+}
diff --git a/src/error.h b/src/error.h
index 7fcddaf4a..dded9f93d 100644
--- a/src/error.h
+++ b/src/error.h
@@ -11,9 +11,60 @@
  */
 
 #include <dbus/dbus.h>
+#include <stdint.h>
 
 #define ERROR_INTERFACE "org.bluez.Error"
 
+/* BR/EDR connection failure reasons */
+#define ERR_BREDR_CONN_ALREADY_CONNECTED	"br-connection-already-"\
+						"connected"
+#define ERR_BREDR_CONN_PAGE_TIMEOUT		"br-connection-page-timeout"
+#define ERR_BREDR_CONN_PROFILE_UNAVAILABLE	"br-connection-profile-"\
+						"unavailable"
+#define ERR_BREDR_CONN_SDP_SEARCH		"br-connection-sdp-search"
+#define ERR_BREDR_CONN_CREATE_SOCKET		"br-connection-create-socket"
+#define ERR_BREDR_CONN_INVALID_ARGUMENTS	"br-connection-invalid-"\
+						"argument"
+#define ERR_BREDR_CONN_ADAPTER_NOT_POWERED	"br-connection-adapter-not-"\
+						"powered"
+#define ERR_BREDR_CONN_NOT_SUPPORTED		"br-connection-not-suuported"
+#define ERR_BREDR_CONN_BAD_SOCKET		"br-connection-bad-socket"
+#define ERR_BREDR_CONN_MEMORY_ALLOC		"br-connection-memory-"\
+						"allocation"
+#define ERR_BREDR_CONN_BUSY			"br-connection-busy"
+#define ERR_BREDR_CONN_CNCR_CONNECT_LIMIT	"br-connection-concurrent-"\
+						"connection-limit"
+#define ERR_BREDR_CONN_TIMEOUT			"br-connection-timeout"
+#define ERR_BREDR_CONN_REFUSED			"br-connection-refused"
+#define ERR_BREDR_CONN_ABORT_BY_REMOTE		"br-connection-aborted-by-"\
+						"remote"
+#define ERR_BREDR_CONN_ABORT_BY_LOCAL		"br-connection-aborted-by-"\
+						"local"
+#define ERR_BREDR_CONN_LMP_PROTO_ERROR		"br-connection-lmp-protocol-"\
+						"error"
+#define ERR_BREDR_CONN_CANCELED			"br-connection-canceled"
+#define ERR_BREDR_CONN_UNKNOWN			"br-connection-unknown"
+
+/* LE connection failure reasons */
+#define ERR_LE_CONN_INVALID_ARGUMENTS	"le-connection-invalid-arguments"
+#define ERR_LE_CONN_ADAPTER_NOT_POWERED	"le-connection-adapter-not-powered"
+#define ERR_LE_CONN_NOT_SUPPORTED	"le-connection-not-supported"
+#define ERR_LE_CONN_ALREADY_CONNECTED	"le-connection-already-connected"
+#define ERR_LE_CONN_BAD_SOCKET		"le-connection-bad-socket"
+#define ERR_LE_CONN_MEMORY_ALLOC	"le-connection-memory-allocation"
+#define ERR_LE_CONN_BUSY		"le-connection-busy"
+#define ERR_LE_CONN_REFUSED		"le-connection-refused"
+#define ERR_LE_CONN_CREATE_SOCKET	"le-connection-create-socket"
+#define ERR_LE_CONN_TIMEOUT		"le-connection-timeout"
+#define ERR_LE_CONN_SYNC_CONNECT_LIMIT	"le-connection-concurrent-connection-"\
+					"limit"
+#define ERR_LE_CONN_ABORT_BY_REMOTE	"le-connection-abort-by-remote"
+#define ERR_LE_CONN_ABORT_BY_LOCAL	"le-connection-abort-by-local"
+#define ERR_LE_CONN_LL_PROTO_ERROR	"le-connection-link-layer-protocol-"\
+					"error"
+#define ERR_LE_CONN_GATT_BROWSE		"le-connection-gatt-browsing"
+#define ERR_LE_CONN_UNKNOWN		"le-connection-unknown"
+
 DBusMessage *btd_error_invalid_args(DBusMessage *msg);
 DBusMessage *btd_error_invalid_args_str(DBusMessage *msg, const char *str);
 DBusMessage *btd_error_busy(DBusMessage *msg);
@@ -22,11 +73,17 @@ DBusMessage *btd_error_not_supported(DBusMessage *msg);
 DBusMessage *btd_error_not_connected(DBusMessage *msg);
 DBusMessage *btd_error_already_connected(DBusMessage *msg);
 DBusMessage *btd_error_not_available(DBusMessage *msg);
+DBusMessage *btd_error_not_available_str(DBusMessage *msg, const char *str);
 DBusMessage *btd_error_in_progress(DBusMessage *msg);
+DBusMessage *btd_error_in_progress_str(DBusMessage *msg, const char *str);
 DBusMessage *btd_error_does_not_exist(DBusMessage *msg);
 DBusMessage *btd_error_not_authorized(DBusMessage *msg);
 DBusMessage *btd_error_not_permitted(DBusMessage *msg, const char *str);
 DBusMessage *btd_error_no_such_adapter(DBusMessage *msg);
 DBusMessage *btd_error_agent_not_available(DBusMessage *msg);
 DBusMessage *btd_error_not_ready(DBusMessage *msg);
+DBusMessage *btd_error_not_ready_str(DBusMessage *msg, const char *str);
 DBusMessage *btd_error_failed(DBusMessage *msg, const char *str);
+
+const char *btd_error_bredr_conn_from_errno(int errno_code);
+const char *btd_error_le_conn_from_errno(int errno_code);
