[PATCH] [media] davinci-vpfe: Fix retcode check

[PATCH] [media] davinci-vpfe: Fix retcode check

[Andrey Utkin]

Use signed type to check correctly for negative error code. The issue
was reported with static analyser:

[linux-3.13/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c:270]:
(style) A pointer can not be negative so it is either pointless or an
error to check if it is.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69071
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
---
 drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c b/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
index b2daf5e..e326032 100644
--- a/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
+++ b/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
@@ -254,7 +254,7 @@ int config_ipipe_hw(struct vpfe_ipipe_device *ipipe)
 	void __iomem *ipipe_base = ipipe->base_addr;
 	struct v4l2_mbus_framefmt *outformat;
 	u32 color_pat;
-	u32 ipipe_mode;
+	int ipipe_mode;
 	u32 data_path;
 
 	/* enable clock to IPIPE */
-- 
1.8.3.2

Re: [PATCH] [media] davinci-vpfe: Fix retcode check

[Levente Kurusa]

2014-07-08 16:08 GMT+02:00 Andrey Utkin <andrey.krieger.utkin@gmail.com>:
> Use signed type to check correctly for negative error code. The issue
> was reported with static analyser:
>
> [linux-3.13/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c:270]:
> (style) A pointer can not be negative so it is either pointless or an
> error to check if it is.
>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69071
> Reported-by: David Binderman <dcb314@hotmail.com>
> Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>

Hmm, while it is true that get_ipipe_mode returns an int, but
the consequent call to regw_ip takes an u32 as its second
argument. Did it cause a build warning for you? (Can't really
check since I don't have ARM cross compilers close-by)
If not, then:

Reviewed-by: Levente Kurusa <lkurusa@redhat.com>

Thanks,
Levente Kurusa

Re: [PATCH] [media] davinci-vpfe: Fix retcode check

[Andrey Utkin]

2014-07-08 17:32 GMT+03:00 Levente Kurusa <lkurusa@redhat.com>:
> Hmm, while it is true that get_ipipe_mode returns an int, but
> the consequent call to regw_ip takes an u32 as its second
> argument. Did it cause a build warning for you? (Can't really
> check since I don't have ARM cross compilers close-by)
> If not, then:

Cannot say for sure would compiler complain.
I also haven't really checked it, and unfortunately even haven't
succeeded to make a config that would build that code. But i believe
that warning is still better than misbehaviour.

-- 
Andrey Utkin

Re: [PATCH] [media] davinci-vpfe: Fix retcode check

[Prabhakar Lad]

Hi Andrey,

Thanks for the patch!

On Tue, Jul 8, 2014 at 3:58 PM, Andrey Utkin
<andrey.krieger.utkin@gmail.com> wrote:
> 2014-07-08 17:32 GMT+03:00 Levente Kurusa <lkurusa@redhat.com>:
>> Hmm, while it is true that get_ipipe_mode returns an int, but
>> the consequent call to regw_ip takes an u32 as its second
>> argument. Did it cause a build warning for you? (Can't really
>> check since I don't have ARM cross compilers close-by)
>> If not, then:
>
> Cannot say for sure would compiler complain.
> I also haven't really checked it, and unfortunately even haven't
> succeeded to make a config that would build that code. But i believe
> that warning is still better than misbehaviour.
>
It wont cause any compile warning.

Applied for v3.17

Thanks,
--Prabhakar Lad

Re: [PATCH] [media] davinci-vpfe: Fix retcode check

[Dan Carpenter]

On Tue, Jul 08, 2014 at 04:32:57PM +0200, Levente Kurusa wrote:
> 2014-07-08 16:08 GMT+02:00 Andrey Utkin <andrey.krieger.utkin@gmail.com>:
> > Use signed type to check correctly for negative error code. The issue
> > was reported with static analyser:
> >
> > [linux-3.13/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c:270]:
> > (style) A pointer can not be negative so it is either pointless or an
> > error to check if it is.
> >
> > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69071
> > Reported-by: David Binderman <dcb314@hotmail.com>
> > Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
> 
> Hmm, while it is true that get_ipipe_mode returns an int, but
> the consequent call to regw_ip takes an u32 as its second
> argument. Did it cause a build warning for you?

It won't cause a compile warning.

> (Can't really
> check since I don't have ARM cross compilers close-by)

Make a small test program and test.

regards,
dan carpenter

[PATCH] [media] davinci-vpfe: Fix retcode check

[Andrey Utkin]

See https://bugzilla.kernel.org/show_bug.cgi?id=69071
---8<---
Use signed type to check correctly for negative error code

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
---
 drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c b/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
index b2daf5e..e326032 100644
--- a/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
+++ b/drivers/staging/media/davinci_vpfe/dm365_ipipe_hw.c
@@ -254,7 +254,7 @@ int config_ipipe_hw(struct vpfe_ipipe_device *ipipe)
 	void __iomem *ipipe_base = ipipe->base_addr;
 	struct v4l2_mbus_framefmt *outformat;
 	u32 color_pat;
-	u32 ipipe_mode;
+	int ipipe_mode;
 	u32 data_path;
 
 	/* enable clock to IPIPE */
-- 
1.8.3.2