[PATCH v2] clk: qoriq: Hold reference returned by of_get_parent()

[PATCH v2] clk: qoriq: Hold reference returned by of_get_parent()

[Liang He]

In legacy_init_clockgen(), we need to hold the reference returned
by of_get_parent() and use it to call of_node_put() for refcount
balance.

Beside, in create_sysclk(), we need to call of_node_put() on 'sysclk'
also for refcount balance.

Fixes: 0dfc86b3173f ("clk: qoriq: Move chip-specific knowledge into driver")
Signed-off-by: Liang He <windhl@126.com>
---
 changelog:

 v2: change 'tp' with 'parent_np', change title format to xx:yy:zz
 v1: hold reference returned by of_get_parent() and |PUT| 'sysclk'
 
 v1-link: https://lore.kernel.org/all/20220624101556.4164258-1-windhl@126.com/

 Patched file has been compiled test in 5.19rc2.


 drivers/clk/clk-qoriq.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/clk-qoriq.c b/drivers/clk/clk-qoriq.c
index 88898b97a443..5eddb9f0d6bd 100644
--- a/drivers/clk/clk-qoriq.c
+++ b/drivers/clk/clk-qoriq.c
@@ -1063,8 +1063,13 @@ static void __init _clockgen_init(struct device_node *np, bool legacy);
  */
 static void __init legacy_init_clockgen(struct device_node *np)
 {
-	if (!clockgen.node)
-		_clockgen_init(of_get_parent(np), true);
+	if (!clockgen.node) {
+		struct device_node *parent_np;
+
+		parent_np = of_get_parent(np);
+		_clockgen_init(parent_np, true);
+		of_node_put(parent_np);
+	}
 }
 
 /* Legacy node */
@@ -1159,6 +1164,7 @@ static struct clk * __init create_sysclk(const char *name)
 	sysclk = of_get_child_by_name(clockgen.node, "sysclk");
 	if (sysclk) {
 		clk = sysclk_from_fixed(sysclk, name);
+		of_node_put(sysclk);
 		if (!IS_ERR(clk))
 			return clk;
 	}
-- 
2.25.1

Re: [PATCH v2] clk: qoriq: Hold reference returned by of_get_parent()

[Stephen Boyd]

Quoting Liang He (2022-06-28 07:38:51)
> In legacy_init_clockgen(), we need to hold the reference returned
> by of_get_parent() and use it to call of_node_put() for refcount
> balance.
> 
> Beside, in create_sysclk(), we need to call of_node_put() on 'sysclk'
> also for refcount balance.
> 
> Fixes: 0dfc86b3173f ("clk: qoriq: Move chip-specific knowledge into driver")
> Signed-off-by: Liang He <windhl@126.com>
> ---

Applied to clk-next