2020-02-23 15:30:26

by Colin King

Subject: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

From: Colin Ian King <[email protected]>

The zero'ing of counter variable k is redundant as it is never read
after breaking out of the while loop. Remove it.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/staging/rtl8723bs/core/rtw_efuse.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_efuse.c b/drivers/staging/rtl8723bs/core/rtw_efuse.c
index 3b8848182221..bdb6ff8aab7d 100644
--- a/drivers/staging/rtl8723bs/core/rtw_efuse.c
+++ b/drivers/staging/rtl8723bs/core/rtw_efuse.c
@@ -244,10 +244,8 @@ u16 Address)
while (!(Bytetemp & 0x80)) {
Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
k++;
- if (k == 1000) {
- k = 0;
+ if (k == 1000)
break;
- }
}
return rtw_read8(Adapter, EFUSE_CTRL);
} else
--
2.25.0

2020-02-24 11:16:01

by walter harms

Subject: AW: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

________________________________________
Von: [email protected] <[email protected]> im Auftrag von Colin King <[email protected]>
Gesendet: Sonntag, 23. Februar 2020 16:28
An: Greg Kroah-Hartman; [email protected]
Cc: [email protected]; [email protected]
Betreff: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

From: Colin Ian King <[email protected]>

The zero'ing of counter variable k is redundant as it is never read
after breaking out of the while loop. Remove it.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/staging/rtl8723bs/core/rtw_efuse.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_efuse.c b/drivers/staging/rtl8723bs/core/rtw_efuse.c
index 3b8848182221..bdb6ff8aab7d 100644
--- a/drivers/staging/rtl8723bs/core/rtw_efuse.c
+++ b/drivers/staging/rtl8723bs/core/rtw_efuse.c
@@ -244,10 +244,8 @@ u16 Address)
while (!(Bytetemp & 0x80)) {
Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
k++;
- if (k == 1000) {
- k = 0;
+ if (k == 1000)
break;
- }

IMHO this is confusing to read, i suggest:

for(k=0;k<1000;k++) {
Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
if ( Bytetemp & 0x80 )
break;
}

NTL is am wondering what will happen if k==1000
and Bytetemp is still invalid. Will rtw_read8() fail or
simply return invalid data ?

ym2c,
re,
wh
}
return rtw_read8(Adapter, EFUSE_CTRL);
} else
--
2.25.0

2020-02-24 11:29:06

by Dan Carpenter

Subject: Re: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

On Mon, Feb 24, 2020 at 11:07:55AM +0000, Walter Harms wrote:
> diff --git a/drivers/staging/rtl8723bs/core/rtw_efuse.c b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> index 3b8848182221..bdb6ff8aab7d 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_efuse.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> @@ -244,10 +244,8 @@ u16 Address)
> while (!(Bytetemp & 0x80)) {
> Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
> k++;
> - if (k == 1000) {
> - k = 0;
> + if (k == 1000)
> break;
> - }
>
> IMHO this is confusing to read, i suggest:
>
> for(k=0;k<1000;k++) {
> Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
> if ( Bytetemp & 0x80 )
> break;
> }
>

The problem with the original code is that the variable is named "k"
instead of "retry". It should be:

do {
Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
} while (!(Bytetemp & 0x80)) && ++retry < 1000);


> NTL is am wondering what will happen if k==1000
> and Bytetemp is still invalid. Will rtw_read8() fail or
> simply return invalid data ?

Yeah. That was my thought reviewing this patch as well.

It should probably return 0xff on failure.

if (retry >= 1000)
return 0xff;

regards,
dan carpenter

2020-02-24 11:46:21

by walter harms

Subject: AW: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

________________________________________
Von: Dan Carpenter <[email protected]>
Gesendet: Montag, 24. Februar 2020 12:27
An: Walter Harms
Cc: Colin King; Greg Kroah-Hartman; [email protected]; [email protected]; [email protected]
Betreff: Re: [PATCH] staging: rtl8723bs: core: remove redundant zero'ing of counter variable k

On Mon, Feb 24, 2020 at 11:07:55AM +0000, Walter Harms wrote:
> diff --git a/drivers/staging/rtl8723bs/core/rtw_efuse.c b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> index 3b8848182221..bdb6ff8aab7d 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_efuse.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_efuse.c
> @@ -244,10 +244,8 @@ u16 Address)
> while (!(Bytetemp & 0x80)) {
> Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
> k++;
> - if (k == 1000) {
> - k = 0;
> + if (k == 1000)
> break;
> - }
>
> IMHO this is confusing to read, i suggest:
>
> for(k=0;k<1000;k++) {
> Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
> if ( Bytetemp & 0x80 )
> break;
> }
>

The problem with the original code is that the variable is named "k"
instead of "retry". It should be:

do {
Bytetemp = rtw_read8(Adapter, EFUSE_CTRL+3);
} while (!(Bytetemp & 0x80)) && ++retry < 1000);

good point,
personally i try to avoid putting to much into braces, so i
would go for the additional if() but this is for the maintainer.


> NTL is am wondering what will happen if k==1000
> and Bytetemp is still invalid. Will rtw_read8() fail or
> simply return invalid data ?

Yeah. That was my thought reviewing this patch as well.

It should probably return 0xff on failure.

if (retry >= 1000)
return 0xff;

looks nice,

re,
wh
regards,
dan carpenter