2019-07-25 16:58:56

by Colin King

Subject: [PATCH][next] can: kvaser_pciefd: remove redundant negative check on trigger

From: Colin Ian King <[email protected]>

The check to see if trigger is less than zero is always false, trigger
is always in the range 0..255. Hence the check is redundant and can
be removed.

Addresses-Coverity: ("Logically dead code")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/net/can/kvaser_pciefd.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/net/can/kvaser_pciefd.c b/drivers/net/can/kvaser_pciefd.c
index 3af747cbbde4..68e00aad0810 100644
--- a/drivers/net/can/kvaser_pciefd.c
+++ b/drivers/net/can/kvaser_pciefd.c
@@ -652,9 +652,6 @@ static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;

trigger = (100 * top + 50) / 100;
- if (trigger < 0)
- trigger = 0;
-
pwm_ctrl = trigger & 0xff;
pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);
--
2.20.1

2019-07-25 17:05:15

by walter harms

Subject: Re: [PATCH][next] can: kvaser_pciefd: remove redundant negative check on trigger

Am 25.07.2019 13:25, schrieb Colin King:
> From: Colin Ian King <[email protected]>
>
> The check to see if trigger is less than zero is always false, trigger
> is always in the range 0..255. Hence the check is redundant and can
> be removed.
>
> Addresses-Coverity: ("Logically dead code")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/net/can/kvaser_pciefd.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/drivers/net/can/kvaser_pciefd.c b/drivers/net/can/kvaser_pciefd.c
> index 3af747cbbde4..68e00aad0810 100644
> --- a/drivers/net/can/kvaser_pciefd.c
> +++ b/drivers/net/can/kvaser_pciefd.c
> @@ -652,9 +652,6 @@ static void kvaser_pciefd_pwm_stop(struct kvaser_pciefd_can *can)
> top = (pwm_ctrl >> KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT) & 0xff;
>
> trigger = (100 * top + 50) / 100;
> - if (trigger < 0)
> - trigger = 0;
> -
to be fair i do not understand the calculation here here.
(100*top+50)/100 = top+50/100

but seems to be int so it should be =top

did i missunderstand something here ?

re,
wh


> pwm_ctrl = trigger & 0xff;
> pwm_ctrl |= (top & 0xff) << KVASER_PCIEFD_KCAN_PWM_TOP_SHIFT;
> iowrite32(pwm_ctrl, can->reg_base + KVASER_PCIEFD_KCAN_PWM_REG);