[PATCH 4.4 190/192] hwrng: exynos - Disable runtime PM on probe failure

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>

commit 48a61e1e2af8020f11a2b8f8dc878144477623c6 upstream.

Add proper error path (for disabling runtime PM) when registering of
hwrng fails.

Fixes: b329669ea0b5 ("hwrng: exynos - Add support for Exynos random number generator")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/char/hw_random/exynos-rng.c |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/char/hw_random/exynos-rng.c
+++ b/drivers/char/hw_random/exynos-rng.c
@@ -118,6 +118,7 @@ static int exynos_rng_probe(struct platf
 {
 	struct exynos_rng *exynos_rng;
 	struct resource *res;
+	int ret;
 
 	exynos_rng = devm_kzalloc(&pdev->dev, sizeof(struct exynos_rng),
 					GFP_KERNEL);
@@ -145,7 +146,13 @@ static int exynos_rng_probe(struct platf
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 
-	return devm_hwrng_register(&pdev->dev, &exynos_rng->rng);
+	ret = devm_hwrng_register(&pdev->dev, &exynos_rng->rng);
+	if (ret) {
+		pm_runtime_dont_use_autosuspend(&pdev->dev);
+		pm_runtime_disable(&pdev->dev);
+	}
+
+	return ret;
 }
 
 #ifdef CONFIG_PM