diff --git a/module/amu_smcf_drv/test/mod_amu_smcf_drv_unit_test.c b/module/amu_smcf_drv/test/mod_amu_smcf_drv_unit_test.c
index 5cd67db5c1f9e32dd8e1a85c703c059df207c670..3eebeed3890da3f44a1e513bfbe8999402e4e227 100644
--- a/module/amu_smcf_drv/test/mod_amu_smcf_drv_unit_test.c
+++ b/module/amu_smcf_drv/test/mod_amu_smcf_drv_unit_test.c
@@ -1,6 +1,6 @@
 /*
  * Arm SCP/MCP Software
- * Copyright (c) 2023, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2023-2024, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -269,6 +269,7 @@ void test_amu_smcf_drv_get_amu_counter_success(void)
         .get_data = test_smcf_get_data_api,
     };
     amu_smcf_drv_ctx.data_api = &data_api;
+
     uint64_t amu_counter_values[10];
 
     for (i = 1; i < NUM_OF_CORES; ++i) {
@@ -301,6 +302,8 @@ void test_amu_smcf_drv_get_amu_counter_success(void)
             }
         }
     }
+
+    amu_smcf_drv_ctx.data_api = NULL;
 }
 
 void test_amu_smcf_drv_get_amu_counter_fail_invalid_param(void)
diff --git a/module/power_domain/test/mod_power_domain_state_checks_unit_test.c b/module/power_domain/test/mod_power_domain_state_checks_unit_test.c
index 2bad5e54248a02bc4772bcb172dadc93fc5f75ff..b47d86a7fa94013dd664ef7b1495813b0ca87437 100644
--- a/module/power_domain/test/mod_power_domain_state_checks_unit_test.c
+++ b/module/power_domain/test/mod_power_domain_state_checks_unit_test.c
@@ -50,7 +50,7 @@ static void init_module_ctx(void)
     mod_pd_ctx_temp.system_pd_ctx =
         &mod_pd_ctx_temp.pd_ctx_table[PD_IDX_COUNT - 1];
 
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i] = pd_ctx_config[i];
         fwk_list_init(&pd_ctx[i].children_list);
     }
@@ -58,7 +58,7 @@ static void init_module_ctx(void)
 
 static void evaluate_valid_state_mask(void)
 {
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         for (unsigned int state = 0;
              state < pd_ctx[i].allowed_state_mask_table_size;
              state++) {
@@ -439,7 +439,7 @@ void test_is_upwards_transition_propagation_true(void)
     pd->cs_support = true;
 
     /* Change the current requested state so a deeper one can be requested */
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i].requested_state = MOD_PD_STATE_ON;
     }
 
@@ -472,7 +472,7 @@ void test_is_upwards_transition_propagation_no_cs_true(void)
     pd->cs_support = false;
 
     /* Swap this round so a deeper state can be requested */
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i].requested_state = MOD_PD_STATE_ON;
     }
 
@@ -507,7 +507,7 @@ void test_is_allowed_by_parent_and_children_denied(void)
     struct pd_ctx *pd = &mod_pd_ctx_temp.pd_ctx_table[PD_IDX_CLUSTER0];
 
     /* Swap this round so a pd can deny it is permitted */
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i].current_state = MOD_PD_STATE_ON;
     }
 
diff --git a/module/power_domain/test/mod_power_domain_unit_test.c b/module/power_domain/test/mod_power_domain_unit_test.c
index 37273972715558a3c996e925238d3bfe014fb46b..cb518b38f9fdcc94804600e06bb4359684bb5260 100644
--- a/module/power_domain/test/mod_power_domain_unit_test.c
+++ b/module/power_domain/test/mod_power_domain_unit_test.c
@@ -41,7 +41,7 @@ static void init_module_ctx(void)
     mod_pd_ctx.pd_count = PD_IDX_COUNT;
     mod_pd_ctx.system_pd_ctx = &mod_pd_ctx.pd_ctx_table[PD_IDX_COUNT - 1];
 
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i] = pd_ctx_config[i];
         pd_ctx[i].driver_api = &pd_driver;
         fwk_list_init(&pd_ctx[i].children_list);
@@ -50,7 +50,7 @@ static void init_module_ctx(void)
 
 static void evaluate_valid_state_mask(void)
 {
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         for (unsigned int state = 0;
              state < pd_ctx[i].allowed_state_mask_table_size;
              state++) {
@@ -812,7 +812,7 @@ void test_process_get_state_request_cs(void)
     pd_ctx[PD_IDX_CLUS0CORE0].composite_state_levels_mask = MOD_PD_CS_STATE_MASK
         << MOD_PD_CS_LEVEL_SHIFT;
 
-    for (int i = 0; i < PD_IDX_COUNT; ++i) {
+    for (unsigned int i = 0; i < PD_IDX_COUNT; ++i) {
         pd_ctx[i].current_state = MOD_PD_STATE_ON;
     }
 
diff --git a/module/sensor_smcf_drv/test/mod_sensor_smcf_drv_unit_test.c b/module/sensor_smcf_drv/test/mod_sensor_smcf_drv_unit_test.c
index b595bc1797283e55d1a309c7d39e1a610574dee6..c6bfdf0c2cc9b14b449644b2e4d3874f1bf8c4d4 100644
--- a/module/sensor_smcf_drv/test/mod_sensor_smcf_drv_unit_test.c
+++ b/module/sensor_smcf_drv/test/mod_sensor_smcf_drv_unit_test.c
@@ -1,6 +1,6 @@
 /*
  * Arm SCP/MCP Software
- * Copyright (c) 2022-2023, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2022-2024, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -288,6 +288,8 @@ void test_sensor_smcf_drv_get_sensor_single_value_success(void)
         expected_sensor_value = (sensor_value_msb << 32) + sensor_value_lsb;
         TEST_ASSERT_EQUAL_UINT64(sensor_value, expected_sensor_value);
     }
+
+    sensor_smcf_drv_ctx.data_api = NULL;
 }
 
 void test_sensor_smcf_drv_get_sensor_single_value_fail_invalid_param(void)