[PATCH] video: fbdev: sis: init.c: Cleaning up redundant condition is always true

[PATCH] video: fbdev: sis: init.c: Cleaning up redundant condition is always true

[Rickard Strandqvist]

Removal of a redundant condition that is always true

This was found using a static code analysis program called cppcheck

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
---
 drivers/video/fbdev/sis/init.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/sis/init.c b/drivers/video/fbdev/sis/init.c
index bd40f5e..9e2dd96 100644
--- a/drivers/video/fbdev/sis/init.c
+++ b/drivers/video/fbdev/sis/init.c
@@ -355,12 +355,12 @@ SiS_GetModeID(int VGAEngine, unsigned int VBFlags, int HDisplay, int VDisplay,
 		}
 		break;
 	case 400:
-		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) && (LCDwidth >= 600))) {
+		if ((!(VBFlags & CRT1_LCDA)) || (LCDwidth >= 600)) {
 			if(VDisplay == 300) ModeIndex = ModeIndex_400x300[Depth];
 		}
 		break;
 	case 512:
-		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 1024) && (LCDwidth >= 768))) {
+		if ((!(VBFlags & CRT1_LCDA)) || (LCDwidth >= 768)) {
 			if(VDisplay == 384) ModeIndex = ModeIndex_512x384[Depth];
 		}
 		break;
-- 
1.7.10.4

Re: [PATCH] video: fbdev: sis: init.c: Cleaning up redundant condition is always true

[Dan Carpenter]

On Thu, Jul 03, 2014 at 11:15:21PM +0200, Rickard Strandqvist wrote:
> diff --git a/drivers/video/fbdev/sis/init.c b/drivers/video/fbdev/sis/init.c
> index bd40f5e..9e2dd96 100644
> --- a/drivers/video/fbdev/sis/init.c
> +++ b/drivers/video/fbdev/sis/init.c
> @@ -355,12 +355,12 @@ SiS_GetModeID(int VGAEngine, unsigned int VBFlags, int HDisplay, int VDisplay,
>  		}
>  		break;
>  	case 400:
> -		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) && (LCDwidth >= 600))) {
> +		if ((!(VBFlags & CRT1_LCDA)) || (LCDwidth >= 600)) {


It might be that this was supposed to be:

		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth <= 800) && (LCDwidth >= 600))) {

But why would people write a range from high to low?  That's crazy
people who write backwards code...

The second condition was supposed to do *something* although it's
unclear what.  I would normally say that we should leave the static
checker warning here instead of guessing.  Perhaps add a comment like
/* fixme:  huh?  What's with this nonsense condition? */  But in this
case it's all dead code because LCDwidth is always zero and the code
hasn't changed since 2.6.12 so I don't care.

regards,
dan carpenter

Re: [PATCH] video: fbdev: sis: init.c: Cleaning up redundant condition is always true

[Noralf Tronnes]

Den 07.07.2014 09:57, skrev Dan Carpenter:
> On Thu, Jul 03, 2014 at 11:15:21PM +0200, Rickard Strandqvist wrote:
>> diff --git a/drivers/video/fbdev/sis/init.c b/drivers/video/fbdev/sis/init.c
>> index bd40f5e..9e2dd96 100644
>> --- a/drivers/video/fbdev/sis/init.c
>> +++ b/drivers/video/fbdev/sis/init.c
>> @@ -355,12 +355,12 @@ SiS_GetModeID(int VGAEngine, unsigned int VBFlags, int HDisplay, int VDisplay,
>>   		}
>>   		break;
>>   	case 400:
>> -		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) && (LCDwidth >= 600))) {
>> +		if ((!(VBFlags & CRT1_LCDA)) || (LCDwidth >= 600)) {
>
> It might be that this was supposed to be:
>
> 		if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth <= 800) && (LCDwidth >= 600))) {
>
> But why would people write a range from high to low?  That's crazy
> people who write backwards code...
The numbers 800x600 (1024x768) indicate that LCDheight is meant to be used:
                  if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) && 
(LCDheight >= 600))) {

regards,
Noralf Tronnes

Re: [PATCH] video: fbdev: sis: init.c: Cleaning up redundant condition is always true

[Rickard Strandqvist]

2014-07-07 11:23 GMT+02:00 Noralf Tronnes <notro@tronnes.org>:
> Den 07.07.2014 09:57, skrev Dan Carpenter:
>
>> On Thu, Jul 03, 2014 at 11:15:21PM +0200, Rickard Strandqvist wrote:
>>>
>>> diff --git a/drivers/video/fbdev/sis/init.c
>>> b/drivers/video/fbdev/sis/init.c
>>> index bd40f5e..9e2dd96 100644
>>> --- a/drivers/video/fbdev/sis/init.c
>>> +++ b/drivers/video/fbdev/sis/init.c
>>> @@ -355,12 +355,12 @@ SiS_GetModeID(int VGAEngine, unsigned int VBFlags,
>>> int HDisplay, int VDisplay,
>>>                 }
>>>                 break;
>>>         case 400:
>>> -               if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) &&
>>> (LCDwidth >= 600))) {
>>> +               if ((!(VBFlags & CRT1_LCDA)) || (LCDwidth >= 600)) {
>>
>>
>> It might be that this was supposed to be:
>>
>>                 if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth <= 800) &&
>> (LCDwidth >= 600))) {
>>
>> But why would people write a range from high to low?  That's crazy
>> people who write backwards code...
>
> The numbers 800x600 (1024x768) indicate that LCDheight is meant to be used:
>                  if((!(VBFlags & CRT1_LCDA)) || ((LCDwidth >= 800) &&
> (LCDheight >= 600))) {
>
> regards,
> Noralf Tronnes

Hi

Nice, this is what is the point of fix this type of minor errors.
Sometimes you can find something more serious :)

New patch on the way!

Kind regards
Rickard Strandqvist