policy: make steering ability evaluation uniform

Usteer imposes minimum intervals for steering actions in order to avoid
creating endless roam-kick loops due to the decentral aspect of usteer.

Make these basic limits to roamsteering usable across band-steering and
signal-based roam-steering.

Signed-off-by: David Bauer <mail@david-bauer.net>

policy.c

@@ -378,17 +378,12 @@ usteer_roam_trigger_sm(struct usteer_local_node *ln, struct sta_info *si)
 	return false;
 }
 
-static bool
-usteer_local_node_roam_sm_active(struct sta_info *si, int min_signal)
+bool usteer_policy_can_perform_roam(struct sta_info *si)
 {
 	/* Only trigger for connected STAs */
 	if (si->connected != STA_CONNECTED)
 		return false;
 
-	/* Signal has to be below scan / roam threshold */
-	if (si->signal >= min_signal)
-		return false;
-
 	/* Skip on pending kick */
 	if (si->kick_time)
 		return false;
@@ -408,6 +403,19 @@ usteer_local_node_roam_sm_active(struct sta_info *si, int min_signal)
 	return true;
 }
 
+static bool
+usteer_local_node_roam_sm_active(struct sta_info *si, int min_signal)
+{
+	if (!usteer_policy_can_perform_roam(si))
+		return false;
+
+	/* Signal has to be below scan / roam threshold */
+	if (si->signal >= min_signal)
+		return false;
+
+	return true;
+}
+
 static void
 usteer_local_node_roam_check(struct usteer_local_node *ln, struct uevent *ev)
 {