[PATCH] powerpc: kernel: Fix missing of_node_put() in add_legacy_soc_port()

[Liang He]

We should call of_node_put() for the reference 'tsi' returned by
of_get_parent() which will increase the refcount.

Signed-off-by: Liang He <windhl at 126.com>
---
 Inserting of_node_put() in the 'if' condition is learned from Orsan:
 https://lore.kernel.org/all/CA+H2tpH1hN1AJ=6vVGQXw6bZ7xQDbzXdaEV_OqWMnw+UxQKCkg@mail.gmail.com/

 I move the of_get_parent() just before its first usage, otherwise, we
 need lots of of_node_put() before the 'return'.

 arch/powerpc/kernel/legacy_serial.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c
index f048c424c525..c7e9d7b5df8c 100644
--- a/arch/powerpc/kernel/legacy_serial.c
+++ b/arch/powerpc/kernel/legacy_serial.c
@@ -166,7 +166,7 @@ static int __init add_legacy_soc_port(struct device_node *np,
 {
 	u64 addr;
 	const __be32 *addrp;
-	struct device_node *tsi = of_get_parent(np);
+	struct device_node *tsi;
 
 	/* We only support ports that have a clock frequency properly
 	 * encoded in the device-tree.
@@ -194,7 +194,8 @@ static int __init add_legacy_soc_port(struct device_node *np,
 	/* Add port, irq will be dealt with later. We passed a translated
 	 * IO port value. It will be fixed up later along with the irq
 	 */
-	if (of_node_is_type(tsi, "tsi-bridge"))
+	tsi = of_get_parent(np);
+	if (of_node_is_type(tsi, "tsi-bridge") || (of_node_put(tsi), 0))
 		return add_legacy_port(np, -1, UPIO_TSI, addr, addr,
 				       0, legacy_port_flags, 0);
 	else
-- 
2.25.1