ab: Change slot selection buttons

Change the behavior of the buttons in the A/B sample from toggling into
the other slot to binding each button to a single slot (button 0 -> slot
A, button 1 -> slot B).

Ref: NCSDK-36121

Signed-off-by: Tomasz Chyrowicz <[email protected]>

Author: tomchy

samples/dfu/ab/README.rst

@@ -72,8 +72,8 @@ Otherwise, it is running from slot A.
 If the project does not use the Partition Manager (a configuration currently only supported on the nRF54H20), the currently running slot can be identified by comparing the address pointed `zephyr,code-partition` to specific node addresses defined in the device tree.
 The following node partitions are used by default:
 
-* ``slot0_partition`` - Application core, slot A
-* ``slot1_partition`` - Application core, slot B
+* ``cpuapp_slot0_partition`` - Application core, slot A
+* ``cpuapp_slot1_partition`` - Application core, slot B
 * ``cpurad_slot0_partition`` - Radio core, slot A
 * ``cpurad_slot1_partition`` - Radio core, slot B
 
@@ -83,7 +83,7 @@ For example, verifying that the application is running from slot A can be done b
 
     #define IS_RUNNING_FROM_SLOT_A \
         (FIXED_PARTITION_NODE_OFFSET(DT_CHOSEN(zephyr_code_partition)) == \
-         FIXED_PARTITION_OFFSET(slot0_partition))
+         FIXED_PARTITION_OFFSET(cpuapp_slot0_partition))
 
 .. _ab_build_files:
 
@@ -123,7 +123,11 @@ LED 1:
     It will remain off if the application is running from slot A.
 
 Button 0:
-    By pressing this button, the non-active slot will be selected as the preferred slot on the next reboot.
+    By pressing this button, the slot A will be selected as the preferred slot on the next reboot.
+    This preference applies only to the next boot and is cleared after the subsequent reset.
+
+Button 1:
+    By pressing this button, the slot B will be selected as the preferred slot on the next reboot.
     This preference applies only to the next boot and is cleared after the subsequent reset.
 
 Configuration

samples/dfu/ab/src/ab_utils.c

@@ -164,18 +164,18 @@ static void device_healthcheck(void)
 	}
 }
 
-static void toggle_slot_for_single_boot(void)
+static void select_slot_for_single_boot(enum ab_boot_slot slot)
 {
 	int err = 0;
-	enum ab_boot_slot active_slot = active_boot_slot_get();
+	char active_slot = (active_boot_slot_get() == SLOT_A) ? 'A' : 'B';
 	enum boot_slot new_slot = BOOT_SLOT_NONE;
 
-	if (active_slot == SLOT_A) {
-		LOG_INF("Temporarily switching slots (A -> B)");
-		new_slot = BOOT_SLOT_SECONDARY;
-	} else if (active_slot == SLOT_B) {
-		LOG_INF("Temporarily switching slots (B -> A)");
+	if (slot == SLOT_A) {
+		LOG_INF("Temporarily switching slots (%c -> A)", active_slot);
 		new_slot = BOOT_SLOT_PRIMARY;
+	} else if (slot == SLOT_B) {
+		LOG_INF("Temporarily switching slots (%c -> B)", active_slot);
+		new_slot = BOOT_SLOT_SECONDARY;
 	} else {
 		LOG_ERR("Cannot determine active slot, cannot toggle");
 		return;
@@ -206,7 +206,9 @@ static void boot_state_report(void)
 static void button_handler(uint32_t button_state, uint32_t has_changed)
 {
 	if ((has_changed & DK_BTN1_MSK) && (button_state & DK_BTN1_MSK)) {
-		toggle_slot_for_single_boot();
+		select_slot_for_single_boot(SLOT_A);
+	} else if ((has_changed & DK_BTN2_MSK) && (button_state & DK_BTN2_MSK)) {
+		select_slot_for_single_boot(SLOT_B);
 	}
 }