[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Jeroen Hofstee]

Since &rgb2ycbcr_coeff and friends are declared const, but
assigned to a void pointer, clang will warn that the const
is implicity casted away. Add const to indicate the pointer
points to const data to get rid of these warnings.

Cc: Stefano Babic <sbabic@denx.de>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index cefd2dc..31b5a10 100644
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	void * const coeff;
 };
 
 #define SYNC_WAVE 0
-- 
1.8.3.2

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Troy Kisky]

On 6/16/2014 12:41 PM, Jeroen Hofstee wrote:
> Since &rgb2ycbcr_coeff and friends are declared const, but
> assigned to a void pointer, clang will warn that the const
> is implicity casted away. Add const to indicate the pointer
> points to const data to get rid of these warnings.
> 
> Cc: Stefano Babic <sbabic@denx.de>
> Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
> ---
>  drivers/video/ipu_disp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
> index cefd2dc..31b5a10 100644
> --- a/drivers/video/ipu_disp.c
> +++ b/drivers/video/ipu_disp.c
> @@ -33,7 +33,7 @@ enum csc_type_t {
>  
>  struct dp_csc_param_t {
>  	int mode;
> -	void *coeff;
> +	void * const coeff;
>  };
>  
>  #define SYNC_WAVE 0
> 

Doesn't this says the pointer is constant, not that it points to constant data?
So, commit log needs updated or
const void *coeff;

Troy

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Jeroen Hofstee]

Hello Troy,

On ma, 2014-06-16 at 12:52 -0700, Troy Kisky wrote:
> On 6/16/2014 12:41 PM, Jeroen Hofstee wrote:
> > Since &rgb2ycbcr_coeff and friends are declared const, but
> > assigned to a void pointer, clang will warn that the const
> > is implicity casted away. Add const to indicate the pointer
> > points to const data to get rid of these warnings.
> > 
> > Cc: Stefano Babic <sbabic@denx.de>
> > Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
> > ---
> >  drivers/video/ipu_disp.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
> > index cefd2dc..31b5a10 100644
> > --- a/drivers/video/ipu_disp.c
> > +++ b/drivers/video/ipu_disp.c
> > @@ -33,7 +33,7 @@ enum csc_type_t {
> >  
> >  struct dp_csc_param_t {
> >  	int mode;
> > -	void *coeff;
> > +	void * const coeff;
> >  };
> >  
> >  #define SYNC_WAVE 0
> > 
> 
> Doesn't this says the pointer is constant, not that it points to constant data?
> So, commit log needs updated or
> const void *coeff;

yup, it does. Thanks. The patch should be updated actually.

Regards,
Jeroen

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Jeroen Hofstee]

On ma, 2014-06-16 at 12:52 -0700, Troy Kisky wrote:
> On 6/16/2014 12:41 PM, Jeroen Hofstee wrote:
> > Since &rgb2ycbcr_coeff and friends are declared const, but
> > assigned to a void pointer, clang will warn that the const
> > is implicity casted away. Add const to indicate the pointer
> > points to const data to get rid of these warnings.
> > 
> > Cc: Stefano Babic <sbabic@denx.de>
> > Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
> > ---
> >  drivers/video/ipu_disp.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
> > index cefd2dc..31b5a10 100644
> > --- a/drivers/video/ipu_disp.c
> > +++ b/drivers/video/ipu_disp.c
> > @@ -33,7 +33,7 @@ enum csc_type_t {
> >  
> >  struct dp_csc_param_t {
> >  	int mode;
> > -	void *coeff;
> > +	void * const coeff;
> >  };
> >  
> >  #define SYNC_WAVE 0
> > 
> 
> Doesn't this says the pointer is constant, not that it points to constant data?
> So, commit log needs updated or
> const void *coeff;

The reason I wrongly changed it from void const * to void * const was to
circumvent gcc complaining with:

drivers/video/ipu_disp.c: In function ?ipu_dp_csc_setup?:
drivers/video/ipu_disp.c:393:8: warning: assignment discards ?const?
qualifier from pointer target type [enabled by default]

This can be solved with:

@@ -390,7 +390,7 @@ void ipu_dp_csc_setup(int dp, struct dp_csc_param_t
dp_csc_param,
                __raw_writel(reg, DP_COM_CONF());
        }
-       coeff = dp_csc_param.coeff;
+       coeff = (const int (*)[5][3]) dp_csc_param.coeff;
 
        if (coeff) {
                __raw_writel(mask_a((*coeff)[0][0]) |


But I am not too happy with that. Happen to know a better way?

Regards,
Jeroen

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Troy Kisky]

On 6/16/2014 1:37 PM, Jeroen Hofstee wrote:
> On ma, 2014-06-16 at 12:52 -0700, Troy Kisky wrote:
>> On 6/16/2014 12:41 PM, Jeroen Hofstee wrote:
>>> Since &rgb2ycbcr_coeff and friends are declared const, but
>>> assigned to a void pointer, clang will warn that the const
>>> is implicity casted away. Add const to indicate the pointer
>>> points to const data to get rid of these warnings.
>>>
>>> Cc: Stefano Babic <sbabic@denx.de>
>>> Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
>>> ---
>>>  drivers/video/ipu_disp.c | 2 +-
>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
>>> index cefd2dc..31b5a10 100644
>>> --- a/drivers/video/ipu_disp.c
>>> +++ b/drivers/video/ipu_disp.c
>>> @@ -33,7 +33,7 @@ enum csc_type_t {
>>>  
>>>  struct dp_csc_param_t {
>>>  	int mode;
>>> -	void *coeff;
>>> +	void * const coeff;
>>>  };
>>>  
>>>  #define SYNC_WAVE 0
>>>
>>
>> Doesn't this says the pointer is constant, not that it points to constant data?
>> So, commit log needs updated or
>> const void *coeff;
> 
> The reason I wrongly changed it from void const * to void * const was to
> circumvent gcc complaining with:
> 
> drivers/video/ipu_disp.c: In function ?ipu_dp_csc_setup?:
> drivers/video/ipu_disp.c:393:8: warning: assignment discards ?const?
> qualifier from pointer target type [enabled by default]
> 
> This can be solved with:
> 
> @@ -390,7 +390,7 @@ void ipu_dp_csc_setup(int dp, struct dp_csc_param_t
> dp_csc_param,
>                 __raw_writel(reg, DP_COM_CONF());
>         }
> -       coeff = dp_csc_param.coeff;
> +       coeff = (const int (*)[5][3]) dp_csc_param.coeff;
>  
>         if (coeff) {
>                 __raw_writel(mask_a((*coeff)[0][0]) |
> 
> 
> But I am not too happy with that. Happen to know a better way?
> 
> Regards,
> Jeroen
> 


I don't know why it gets that warning. The following doesn't.

diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index cefd2dc..209374f 100644
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -31,9 +31,11 @@ enum csc_type_t {
        CSC_NUM
 };

+typedef int coeff_t[5][3];
+
 struct dp_csc_param_t {
        int mode;
-       void *coeff;
+       const coeff_t *coeff;
 };

 #define SYNC_WAVE 0
@@ -381,7 +383,7 @@ void ipu_dp_csc_setup(int dp, struct dp_csc_param_t dp_csc_param,
                        unsigned char srm_mode_update)
 {
        u32 reg;
-       const int (*coeff)[5][3];
+       const coeff_t *coeff;

        if (dp_csc_param.mode >= 0) {
                reg = __raw_readl(DP_COM_CONF());

[U-Boot] [PATCH] video: ipu_disp: squash clang warning

[Jeroen Hofstee]

Since rgb2ycbcr_coeff and friends are declared const, but assigned
to a void pointer, clang will warn that the const is implicity casted
away. If the pointer is changed to void const * gcc will warn when it
is implicitly casted to a const int array. Just add a correctly
typed pointer instead to prevent these casts and hence the warnings.

Cc: Troy Kisky <troy.kisky@boundarydevices.com>
Cc: Stefano Babic <sbabic@denx.de>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>

---
changes since v1:
  Do actually fix the warning. As pointed out by Troy Kisky
  the patch was doing something different then the commit
  message said.
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index cefd2dc..d5e857c 100644
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	const int (*coeff)[5][3];
 };
 
 #define SYNC_WAVE 0
-- 
1.8.3.2

[U-Boot] [[PATCH v2]] video: ipu_disp: squash clang warning

[Jeroen Hofstee]

Since rgb2ycbcr_coeff and friends are declared const, but assigned
to a void pointer, clang will warn that the const is implicity casted
away. If the pointer is changed to void const * gcc will warn when it
is implicitly casted to a const int array. Just add a correctly
typed pointer instead to prevent these casts and hence the warnings.

Cc: Troy Kisky <troy.kisky@boundarydevices.com>
Cc: Stefano Babic <sbabic@denx.de>
Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>

---
changes since v1:
  Do actually fix the warning. As pointed out by Troy Kisky
  the patch was doing something different then the commit
  message said.

  ... and prefix subject with v2
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/ipu_disp.c b/drivers/video/ipu_disp.c
index cefd2dc..d5e857c 100644
--- a/drivers/video/ipu_disp.c
+++ b/drivers/video/ipu_disp.c
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	const int (*coeff)[5][3];
 };
 
 #define SYNC_WAVE 0
-- 
1.8.3.2

[U-Boot] [[PATCH v2]] video: ipu_disp: squash clang warning

[Anatolij Gustschin]

Hi,

On Tue, 17 Jun 2014 19:20:27 +0200
Jeroen Hofstee <jeroen@myspectrum.nl> wrote:

> Since rgb2ycbcr_coeff and friends are declared const, but assigned
> to a void pointer, clang will warn that the const is implicity casted
> away. If the pointer is changed to void const * gcc will warn when it
> is implicitly casted to a const int array. Just add a correctly
> typed pointer instead to prevent these casts and hence the warnings.
> 
> Cc: Troy Kisky <troy.kisky@boundarydevices.com>
> Cc: Stefano Babic <sbabic@denx.de>
> Signed-off-by: Jeroen Hofstee <jeroen@myspectrum.nl>
> 
> ---
> changes since v1:
>   Do actually fix the warning. As pointed out by Troy Kisky
>   the patch was doing something different then the commit
>   message said.
> 
>   ... and prefix subject with v2
> ---
>  drivers/video/ipu_disp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

applied to u-boot-video/master. Thanks!

Anatolij