cpuidle: dt_idle_genpd: Add helper function to remove genpd topology

commit 9a8fa00 upstream.

Genpd parent and child domain topology created using dt_idle_pd_init_topology()
needs to be removed during error cases.

Add new helper function dt_idle_pd_remove_topology() for same.

Cc: stable@vger.kernel.org
Reviewed-by: Ulf Hanssson <ulf.hansson@linaro.org>
Signed-off-by: Maulik Shah <quic_mkshah@quicinc.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/cpuidle/dt_idle_genpd.c

@@ -152,6 +152,30 @@ int dt_idle_pd_init_topology(struct device_node *np)
 	return 0;
 }
 
+int dt_idle_pd_remove_topology(struct device_node *np)
+{
+	struct device_node *node;
+	struct of_phandle_args child, parent;
+	int ret;
+
+	for_each_child_of_node(np, node) {
+		if (of_parse_phandle_with_args(node, "power-domains",
+					"#power-domain-cells", 0, &parent))
+			continue;
+
+		child.np = node;
+		child.args_count = 0;
+		ret = of_genpd_remove_subdomain(&parent, &child);
+		of_node_put(parent.np);
+		if (ret) {
+			of_node_put(node);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
 struct device *dt_idle_attach_cpu(int cpu, const char *name)
 {
 	struct device *dev;

drivers/cpuidle/dt_idle_genpd.h

@@ -14,6 +14,8 @@ struct generic_pm_domain *dt_idle_pd_alloc(struct device_node *np,
 
 int dt_idle_pd_init_topology(struct device_node *np);
 
+int dt_idle_pd_remove_topology(struct device_node *np);
+
 struct device *dt_idle_attach_cpu(int cpu, const char *name);
 
 void dt_idle_detach_cpu(struct device *dev);
@@ -36,6 +38,11 @@ static inline int dt_idle_pd_init_topology(struct device_node *np)
 	return 0;
 }
 
+static inline int dt_idle_pd_remove_topology(struct device_node *np)
+{
+	return 0;
+}
+
 static inline struct device *dt_idle_attach_cpu(int cpu, const char *name)
 {
 	return NULL;