[PATCH v2] mtd: hyperbus: rpc-if: fix an OF node reference leak

[Yige Jiang <yigejiang86@gmail.com>]

rpcif_hb_probe() gets a child-node reference with of_get_next_child().
The HyperBus core does not consume it, so the driver leaks the
reference on registration failure and remove.

Put the node on registration failure and after unregistering the
HyperBus device on remove. Leave hardware initialization failures on
out_disable_rpm, since no node reference has been acquired there.

Fixes: 5de15b610f78 ("mtd: hyperbus: add Renesas RPC-IF driver")
Assisted-by: LLM
Signed-off-by: Yige Jiang <yigejiang86@gmail.com>
---
Changes in v2:
- Move of_node_put() before pm_runtime_disable() in the remove path
  to match the probe error path, as suggested by Miquel Raynal.

v1: https://patchwork.ozlabs.org/project/linux-mtd/patch/rc-review-20261023-ai33-33-fd231771d138@gmail.com/

Based on linux-next next-20261016 (2efb7a11f1aa).
Compile-tested: arm64, GCC 14.2.0, W=1, CONFIG_OF_DYNAMIC=y.
CONFIG_COMPILE_TEST=y.
The object was rebuilt from this exact base with v2 applied.
No full kernel or module-link, hardware or runtime test was performed.

 drivers/mtd/hyperbus/rpc-if.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/hyperbus/rpc-if.c b/drivers/mtd/hyperbus/rpc-if.c
index f448e23f9260f10abe17842849b312365dcd8294..ffa6578b5d399d19d3cac27d7769cccfceb0be92 100644
--- a/drivers/mtd/hyperbus/rpc-if.c
+++ b/drivers/mtd/hyperbus/rpc-if.c
@@ -145,10 +145,12 @@ static int rpcif_hb_probe(struct platform_device *pdev)
 	hyperbus->hbdev.np = of_get_next_child(pdev->dev.parent->of_node, NULL);
 	error = hyperbus_register_device(&hyperbus->hbdev);
 	if (error)
-		goto out_disable_rpm;
+		goto out_put_node;
 
 	return 0;
 
+out_put_node:
+	of_node_put(hyperbus->hbdev.np);
 out_disable_rpm:
 	pm_runtime_disable(hyperbus->rpc.dev);
 	return error;
@@ -159,6 +161,7 @@ static void rpcif_hb_remove(struct platform_device *pdev)
 	struct rpcif_hyperbus *hyperbus = platform_get_drvdata(pdev);
 
 	hyperbus_unregister_device(&hyperbus->hbdev);
+	of_node_put(hyperbus->hbdev.np);
 
 	pm_runtime_disable(hyperbus->rpc.dev);
 }

base-commit: 2efb7a11f1aa4d2dc285fe2680cca22cb9f72f64
-- 
2.50.1 (Apple Git-155)