2021-02-09 06:28:09

by Tian Tao

Subject: [PATCH] hwrng: bcm2835 - remove redundant null check

clk_prepare_enable() and clk_disable_unprepare() will check
NULL clock parameter, so It is not necessary to add additional checks.

Signed-off-by: Tian Tao <[email protected]>
---
drivers/char/hw_random/bcm2835-rng.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 1a7c43b..ed0aa51 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -88,11 +88,9 @@ static int bcm2835_rng_init(struct hwrng *rng)
int ret = 0;
u32 val;

- if (!IS_ERR(priv->clk)) {
- ret = clk_prepare_enable(priv->clk);
- if (ret)
- return ret;
- }
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ return ret;

if (priv->mask_interrupts) {
/* mask the interrupt */
@@ -115,8 +113,7 @@ static void bcm2835_rng_cleanup(struct hwrng *rng)
/* disable rng hardware */
rng_writel(priv, 0, RNG_CTRL);

- if (!IS_ERR(priv->clk))
- clk_disable_unprepare(priv->clk);
+ clk_disable_unprepare(priv->clk);
}

struct bcm2835_rng_of_data {
--
2.7.4

2021-02-10 00:06:20

by Florian Fainelli

Subject: Re: [PATCH] hwrng: bcm2835 - remove redundant null check

On 2/8/21 10:25 PM, Tian Tao wrote:
> clk_prepare_enable() and clk_disable_unprepare() will check
> NULL clock parameter, so It is not necessary to add additional checks.
>
> Signed-off-by: Tian Tao <[email protected]>

I don't believe this is going to work unless you also change
devm_clk_get() to devm_clk_get_optional() which will deal with -ENOENT
and return NULL in that case, once you do that we can remove the NULL
pointer checks.
--
Florian