clk: st: Hold reference returned by of_get_parent()

We should hold the reference returned by of_get_parent() and use it
to call of_node_put() for refcount balance.

Fixes: 3efe64ef ("clk: st: clkgen-fsyn: search reg within node or parent")
Fixes: 810251b0 ("clk: st: clkgen-mux: search reg within node or parent")
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220628142416.169808-1-windhl@126.comSigned-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/st/clkgen-fsyn.c

@@ -987,6 +987,7 @@ static void __init st_of_quadfs_setup(struct device_node *np,
 	const char *pll_name, *clk_parent_name;
 	void __iomem *reg;
 	spinlock_t *lock;
+	struct device_node *parent_np;
 
 	/*
 	 * First check for reg property within the node to keep backward
@@ -994,7 +995,9 @@ static void __init st_of_quadfs_setup(struct device_node *np,
 	 */
 	reg = of_iomap(np, 0);
 	if (!reg) {
-		reg = of_iomap(of_get_parent(np), 0);
+		parent_np = of_get_parent(np);
+		reg = of_iomap(parent_np, 0);
+		of_node_put(parent_np);
 		if (!reg) {
 			pr_err("%s: Failed to get base address\n", __func__);
 			return;

drivers/clk/st/clkgen-mux.c

@@ -56,6 +56,7 @@ static void __init st_of_clkgen_mux_setup(struct device_node *np,
 	void __iomem *reg;
 	const char **parents;
 	int num_parents = 0;
+	struct device_node *parent_np;
 
 	/*
 	 * First check for reg property within the node to keep backward
@@ -63,7 +64,9 @@ static void __init st_of_clkgen_mux_setup(struct device_node *np,
 	 */
 	reg = of_iomap(np, 0);
 	if (!reg) {
-		reg = of_iomap(of_get_parent(np), 0);
+		parent_np = of_get_parent(np);
+		reg = of_iomap(parent_np, 0);
+		of_node_put(parent_np);
 		if (!reg) {
 			pr_err("%s: Failed to get base address\n", __func__);
 			return;