add support for lily58

app/boards/shields/lily58/Kconfig.defconfig

@@ -1,18 +1,38 @@
 
+if SHIELD_LILY58_LEFT || SHIELD_LILY58_RIGHT
+
+config ZMK_SPLIT
+	default y
+
 if SHIELD_LILY58_LEFT
 
 config ZMK_KEYBOARD_NAME
 	default "Lily58"
 
+if ZMK_BLE
 config ZMK_SPLIT_BLE_ROLE_CENTRAL
 	default y
-
 endif
 
-if SHIELD_LILY58_LEFT || SHIELD_LILY58_RIGHT
+if ZMK_USB
+choice ZMK_SPLIT_SERIAL_ROLE
+	default ZMK_SPLIT_SERIAL_ROLE_CENTRAL
+endchoice
+endif
 
-config ZMK_SPLIT
-	default y
+#SHIELD_LILY58_LEFT
+endif
+
+if SHIELD_LILY58_RIGHT
+
+if ZMK_USB
+choice ZMK_SPLIT_SERIAL_ROLE
+	default ZMK_SPLIT_SERIAL_ROLE_PERIPHERAL
+endchoice
+endif
+
+#SHIELD_LILY58_LEFT
+endif
 
 if ZMK_DISPLAY
 

app/boards/shields/lily58/boards/stemcell.overlay

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2022 The ZMK Contributors
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+/ {
+	chosen {
+		zmk,split-serial = &usart2;
+	};
+};
+
+&usart2 {
+	status = "okay";
+};
+