[PATCH v1] hwrng: ks-sa: Fix runtime PM cleanup on registration failure

[Yuho Choi]

ks_sa_rng_probe() enables runtime PM and resumes the device before
registering the hwrng. If devm_hwrng_register() fails, probe returns
without dropping the runtime PM usage count or disabling runtime PM.

Unwind the runtime PM state on the registration failure path, matching
the cleanup done by remove().

Fixes: e9009fb227fa ("hwrng: ks-sa - Use pm_runtime_resume_and_get() to replace open coding")
Signed-off-by: Yuho Choi <dbgh9129@xxxxxxxxx>
---
 drivers/char/hw_random/ks-sa-rng.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/char/hw_random/ks-sa-rng.c b/drivers/char/hw_random/ks-sa-rng.c
index 9e408144a10c..4494f1e4ab4d 100644
--- a/drivers/char/hw_random/ks-sa-rng.c
+++ b/drivers/char/hw_random/ks-sa-rng.c
@@ -242,7 +242,14 @@ static int ks_sa_rng_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, ret, "Failed to enable SA power-domain\n");
 	}
 
-	return devm_hwrng_register(&pdev->dev, &ks_sa_rng->rng);
+	ret = devm_hwrng_register(dev, &ks_sa_rng->rng);
+	if (ret) {
+		pm_runtime_put_sync(dev);
+		pm_runtime_disable(dev);
+		return ret;
+	}
+
+	return 0;
 }
 
 static void ks_sa_rng_remove(struct platform_device *pdev)
-- 
2.43.0