boards: st: nucleo_wb09ke: Optimize power consumption

Optimize power consumption for the Nucleo-WB09KE board by
implementing correct pull-up/pull-down configurations when the device
enters lower power states.

Signed-off-by: Ali Hozhabri <[email protected]>

Author: HoZHel

boards/st/nucleo_wb09ke/CMakeLists.txt

@@ -0,0 +1,5 @@
+# Copyright (c) 2025 STMicroelectronics
+#
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library_sources_ifdef(CONFIG_PM board.c)

boards/st/nucleo_wb09ke/board.c

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2025 STMicroelectronics
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/init.h>
+#include "stm32wb0x_ll_pwr.h"
+
+/* Implement the correct Pull-up/pull-down for GPIOA and GPIOB
+ * to reach the minimum power consumption.
+ */
+static int board_pupd_init(void)
+{
+	LL_PWR_EnableGPIOPullUp(LL_PWR_GPIO_A, 
+				LL_PWR_GPIO_BIT_0|
+				LL_PWR_GPIO_BIT_1|
+				LL_PWR_GPIO_BIT_2|
+				LL_PWR_GPIO_BIT_3);
+  
+	LL_PWR_EnableGPIOPullDown(LL_PWR_GPIO_A, 
+				  LL_PWR_GPIO_BIT_8|
+				  LL_PWR_GPIO_BIT_9|
+				  LL_PWR_GPIO_BIT_10|
+				  LL_PWR_GPIO_BIT_11);
+  
+	LL_PWR_EnableGPIOPullDown(LL_PWR_GPIO_B, 
+				  LL_PWR_GPIO_BIT_0|
+				  LL_PWR_GPIO_BIT_3|
+				  LL_PWR_GPIO_BIT_6|
+				  LL_PWR_GPIO_BIT_7);
+  
+	LL_PWR_EnableGPIOPullUp(LL_PWR_GPIO_B, 
+				LL_PWR_GPIO_BIT_1|
+				LL_PWR_GPIO_BIT_2|
+				LL_PWR_GPIO_BIT_4|
+				LL_PWR_GPIO_BIT_5|
+				LL_PWR_GPIO_BIT_14|
+				LL_PWR_GPIO_BIT_15);
+
+	return 0;
+}
+
+SYS_INIT(board_pupd_init, PRE_KERNEL_2, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);