samples: stm32: serial_wakeup: b_u585i_iot02a support

Add a sample overlay for b_u585i_iot02a

Signed-off-by: Erwan Gouriou <[email protected]>

Author: erwango

samples/boards/stm32/power_mgmt/serial_wakeup/boards/b_u585i_iot02a.overlay

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2023 STMicroelectronics
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+&cpu0{
+	/* USART Wakeup requires automatic HSI16 switch on in deepsleep mode
+	 * which isn't possible in Stop Mode 2.
+	 * Remove Stop Mode 2 from supported modes
+	 */
+	cpu-power-states = <&stop0 &stop1>;
+};
+
+&usart1 {
+	/* Set domain clock to HSI to allow wakeup from Stop mode */
+	clocks = <&rcc STM32_CLOCK_BUS_APB2 0x00004000>,
+		 <&rcc STM32_SRC_HSI16 USART1_SEL(2)>;
+
+	/* Configure device as wakeup source */
+	wakeup-source;
+
+	/* Configure sleep pinctrl configuration which will be used when
+	 * device is not configured as wakeup source by the application.
+	 * This use case is only applicable in PM_DEVICE mode.
+	 */
+	pinctrl-1 = <&analog_pa9 &analog_pa10>;
+	pinctrl-names = "default", "sleep";
+};
+
+&clk_hsi {
+	/* Make sure HSI is enabled */
+	status = "okay";
+};