[PATCH] hwrng: cctrng - fix usage counter in error path

[PATCH] hwrng: cctrng - fix usage counter in error path

[Martin Kaiser]

If probe fails after the runtime pm usage counter was incremented,
we have to decrement it before we exit.

Remove the cc_trng_pm_fini call in the error path. It calls
pm_runtime_disable before runtime pm is enabled.

Fixes: a583ed310bb6 ("hwrng: cctrng - introduce Arm CryptoCell driver")
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
based on sashiko review
https://lore.kernel.org/linux-crypto/67844d9d-d4d4-4026-9549-73589afcc1ff@wanadoo.fr/T/#m1a770f5f9eeed95b48cad7545580aed4fa74e6fa

compile-tested only

 drivers/char/hw_random/cctrng.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/char/hw_random/cctrng.c b/drivers/char/hw_random/cctrng.c
index 03401ee59a8e..d9492d25ecbb 100644
--- a/drivers/char/hw_random/cctrng.c
+++ b/drivers/char/hw_random/cctrng.c
@@ -533,9 +533,9 @@ static int cctrng_probe(struct platform_device *pdev)
 	/* registration of the hwrng device */
 	rc = devm_hwrng_register(dev, &drvdata->rng);
 	if (rc) {
-		dev_err(dev, "Could not register hwrng device.\n");
-		cc_trng_pm_fini(drvdata);
-		return rc;
+		pm_runtime_put_noidle(dev);
+		return dev_err_probe(dev, rc,
+				     "Could not register hwrng device: %d\n", rc);
 	}
 
 	/* trigger HW to start generate data */
-- 
2.43.7

Re: [PATCH] hwrng: cctrng - fix usage counter in error path

[Christophe JAILLET]

Le 29/10/2026 à 09:15, Martin Kaiser a écrit :
> If probe fails after the runtime pm usage counter was incremented,
> we have to decrement it before we exit.
>
> Remove the cc_trng_pm_fini call in the error path. It calls
> pm_runtime_disable before runtime pm is enabled.
>
> Fixes: a583ed310bb6 ("hwrng: cctrng - introduce Arm CryptoCell driver")
> Signed-off-by: Martin Kaiser <martin@kaiser.cx>
> ---
> based on sashiko review
> https://lore.kernel.org/linux-crypto/67844d9d-d4d4-4026-9549-73589afcc1ff@wanadoo.fr/T/#m1a770f5f9eeed95b48cad7545580aed4fa74e6fa
>
> compile-tested only
>
>   drivers/char/hw_random/cctrng.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/char/hw_random/cctrng.c b/drivers/char/hw_random/cctrng.c
> index 03401ee59a8e..d9492d25ecbb 100644
> --- a/drivers/char/hw_random/cctrng.c
> +++ b/drivers/char/hw_random/cctrng.c
> @@ -533,9 +533,9 @@ static int cctrng_probe(struct platform_device *pdev)
>   	/* registration of the hwrng device */
>   	rc = devm_hwrng_register(dev, &drvdata->rng);
>   	if (rc) {
> -		dev_err(dev, "Could not register hwrng device.\n");
> -		cc_trng_pm_fini(drvdata);
> -		return rc;
> +		pm_runtime_put_noidle(dev);
> +		return dev_err_probe(dev, rc,
> +				     "Could not register hwrng device: %d\n", rc);

No need to duplicate rc in a dev_err_probe() call.

CJ

>   	}
>   
>   	/* trigger HW to start generate data */