tests: power_states: Verifies the transition to all available power states

During the test, pytest detects each step and calculates
the RMS (Root Mean Square) current for every detected state.
The test then compares the calculated RMS values
against the expected values.

Signed-off-by: Arkadiusz Cholewinski <arkadiuszx.cholewinski@intel.com>

tests/subsys/pm/power_states/CMakeLists.txt

@@ -0,0 +1,9 @@
+# Copyright (c) 2025 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(power_states)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

tests/subsys/pm/power_states/boards/stm32l562e_dk.overlay

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2025 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+/ {
+	zephyr,user {
+		k_idle_state_min_residency_time = <400000>;
+	};
+};
+
+&stop0{
+	compatible = "zephyr,power-state";
+	power-state-name = "suspend-to-idle";
+	substate-id = <1>;
+	min-residency-us = <500000>;
+};
+&stop1{
+	compatible = "zephyr,power-state";
+	power-state-name = "suspend-to-idle";
+	substate-id = <2>;
+	min-residency-us = <1000000>;
+};
+&stop2{
+	compatible = "zephyr,power-state";
+	power-state-name = "suspend-to-idle";
+	substate-id = <3>;
+	min-residency-us = <1500000>;
+};

tests/subsys/pm/power_states/prj.conf

@@ -0,0 +1,4 @@
+# Copyright (c) 2025 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+CONFIG_PM=y

tests/subsys/pm/power_states/src/main.c

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2025 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <zephyr/kernel.h>
+
+int main(void)
+{
+	int k_idle_min_residency_time =
+		DT_PROP(DT_PATH(zephyr_user), k_idle_state_min_residency_time);
+	int stop0_min_residency_time = DT_PROP(DT_NODELABEL(stop0), min_residency_us);
+	int stop1_min_residency_time = DT_PROP(DT_NODELABEL(stop1), min_residency_us);
+	int stop2_min_residency_time = DT_PROP(DT_NODELABEL(stop2), min_residency_us);
+
+	while (1) {
+		printk("\nGoing to k_cpu_idle.\n");
+		k_usleep(k_idle_min_residency_time);
+		printk("\nWake Up.\n");
+		printk("\nGoing to state 0.\n");
+		k_usleep(stop0_min_residency_time);
+		printk("\nWake Up.\n");
+		printk("\nGoing to state 1.\n");
+		k_usleep(stop1_min_residency_time);
+		printk("\nWake Up.\n");
+		printk("\nGoing to state 2.\n");
+		k_usleep(stop2_min_residency_time);
+		printk("\nWake Up.\n");
+
+		/* Anti-sleeping loop */
+		while (1) {
+			arch_nop();
+		}
+	}
+	return 0;
+}

tests/subsys/pm/power_states/testcase.yaml

@@ -0,0 +1,50 @@
+# Copyright (c) 2025 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+common:
+  harness: power
+  harness_config:
+    fixture: pm_probe
+    pytest_dut_scope: session
+    power_measurements:
+      elements_to_trim: 100
+      min_peak_distance: 40
+      min_peak_height: 0.008
+      peak_padding: 40
+      measurement_duration: 6
+      num_of_transitions: 4
+      expected_rms_values: [56.0, 4.0, 1.4, 0.26, 140]
+      tolerance_percentage: 10
+
+tests:
+  pm.power_states:
+    platform_allow:
+      - stm32l562e_dk
+    tags:
+      - pm
+
+  pm.power_states.pm_device:
+    platform_allow:
+      - stm32l562e_dk
+    tags:
+      - pm
+    extra_args:
+      - CONFIG_PM_DEVICE=y
+
+  pm.power_states.pm_device_runtime:
+    platform_allow:
+      - stm32l562e_dk
+    tags:
+      - pm
+    extra_args:
+      - CONFIG_PM_DEVICE=y
+      - CONFIG_PM_DEVICE_RUNTIME=y
+
+  pm.power_states.pm_device_system_managed:
+    platform_allow:
+      - stm32l562e_dk
+    tags:
+      - pm
+    extra_args:
+      - CONFIG_PM_DEVICE=y
+      - CONFIG_PM_DEVICE_SYSTEM_MANAGED=y