2021-05-19 19:28:38

by Jiapeng Chong

Subject: [PATCH] net: dsa: Remove unsigned expression compared with zero

Variable val is "u32" always >= 0, so val >= 0 condition are redundant.

Clean up the following coccicheck warning:

./drivers/net/dsa/qca8k.c:732:5-8: WARNING: Unsigned expression compared
with zero: val >= 0.

Reported-by: Abaci Robot <[email protected]>
Signed-off-by: Jiapeng Chong <[email protected]>
---
drivers/net/dsa/qca8k.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
index 4753228..7b38b8d 100644
--- a/drivers/net/dsa/qca8k.c
+++ b/drivers/net/dsa/qca8k.c
@@ -729,8 +729,7 @@

mutex_unlock(&bus->mdio_lock);

- if (val >= 0)
- val &= QCA8K_MDIO_MASTER_DATA_MASK;
+ val &= QCA8K_MDIO_MASTER_DATA_MASK;

return val;
}
--
1.8.3.1

2021-05-19 20:20:19

by Vladimir Oltean

Subject: Re: [PATCH] net: dsa: Remove unsigned expression compared with zero

Hi Jiapeng,

On Wed, May 19, 2021 at 06:49:51PM +0800, Jiapeng Chong wrote:
> Variable val is "u32" always >= 0, so val >= 0 condition are redundant.
>
> Clean up the following coccicheck warning:
>
> ./drivers/net/dsa/qca8k.c:732:5-8: WARNING: Unsigned expression compared
> with zero: val >= 0.
>
> Reported-by: Abaci Robot <[email protected]>
> Signed-off-by: Jiapeng Chong <[email protected]>
> ---
> drivers/net/dsa/qca8k.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c
> index 4753228..7b38b8d 100644
> --- a/drivers/net/dsa/qca8k.c
> +++ b/drivers/net/dsa/qca8k.c
> @@ -729,8 +729,7 @@
>
> mutex_unlock(&bus->mdio_lock);
>
> - if (val >= 0)
> - val &= QCA8K_MDIO_MASTER_DATA_MASK;
> + val &= QCA8K_MDIO_MASTER_DATA_MASK;
>
> return val;
> }
> --
> 1.8.3.1
>

The qca8k driver has some problems with the handling of signed/unsigned
return values. I would suggest a better approach to be to make
qca8k_mii_read32 to return an int value, and keep this check as is.