video: ipu_disp: squash clang warning

PATCH New Jeroen Hofstee 3 participants 8 messages Jun 16, 2014 – Aug 11, 2014 Framebuffer layer

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Jeroen Hofstee

author

2014-06-16 19:41 UTC #0 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

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 <[email protected]>

Signed-off-by Jeroen Hofstee <[email protected]>

---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/video/ipu_disp.c +1 -1

index cefd2dc..31b5a10 100644
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	void * const coeff;
 };
 
 #define SYNC_WAVE 0

Signature · 1 line

1.8.3.2

Troy Kisky

2014-06-16 19:52 UTC #1 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

Quoted 17 lines · 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 <[email protected]>
Signed-off-by Jeroen Hofstee <[email protected]>
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/video/ipu_disp.c +0 -0
index cefd2dc..31b5a10 100644

drivers/video/ipu_disp.c enum csc_type_t { · line 39

Quoted 8 lines

drivers/video/ipu_disp.c +1 -1

@@ -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

Jeroen Hofstee

author

2014-06-16 20:03 UTC #2 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

Hello Troy,

Quoted 24 lines · Troy Kisky

Quoted 23 lines · 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 <[email protected]>
Signed-off-by Jeroen Hofstee <[email protected]>
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/video/ipu_disp.c +1 -1
index cefd2dc..31b5a10 100644
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	void * const coeff;
 };
 

Quoted 6 lines

drivers/video/ipu_disp.c enum csc_type_t { · line 39
Quoted 2 lines
drivers/video/ipu_disp.c +0 -0
 #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

Jeroen Hofstee

author

2014-06-16 20:37 UTC #3 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

In reply to Troy Kisky

Quoted 24 lines · Troy Kisky

Quoted 23 lines · 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 <[email protected]>
Signed-off-by Jeroen Hofstee <[email protected]>
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/video/ipu_disp.c +1 -1
index cefd2dc..31b5a10 100644
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	void * const coeff;
 };
 

Quoted 6 lines

drivers/video/ipu_disp.c enum csc_type_t { · line 39
Quoted 2 lines
drivers/video/ipu_disp.c +0 -0
 #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

Troy Kisky

2014-06-16 21:50 UTC #4 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

Quoted 52 lines · Jeroen Hofstee

Quoted 24 lines · Troy Kisky
Quoted 23 lines · 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 <[email protected]>
Signed-off-by Jeroen Hofstee <[email protected]>
---
 drivers/video/ipu_disp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/video/ipu_disp.c +1 -1
index cefd2dc..31b5a10 100644
@@ -33,7 +33,7 @@ enum csc_type_t {
 
 struct dp_csc_param_t {
 	int mode;
-	void *coeff;
+	void * const coeff;
 };
 
Quoted 6 lines
drivers/video/ipu_disp.c enum csc_type_t { · line 39
Quoted 2 lines
drivers/video/ipu_disp.c +0 -0
 #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:
(quoted diff) +1 -1
@@ -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]) |

Quoted 5 lines

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.

drivers/video/ipu_disp.c +4 -2

index cefd2dc..209374f 100644
@@ -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());

Jeroen Hofstee

author

2014-06-17 17:16 UTC #5 lore raw

PATCH 1/1 video: ipu_disp: squash clang warning

In reply to 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 <[email protected]>

Cc Stefano Babic <[email protected]>

Signed-off-by Jeroen Hofstee <[email protected]>

---
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(-)

drivers/video/ipu_disp.c +1 -1

index cefd2dc..d5e857c 100644
@@ -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

Signature · 1 line

1.8.3.2

Jeroen Hofstee

author

2014-06-17 17:20 UTC #6 lore raw

PATCH v2 1/1 ] video: ipu_disp: squash clang warning

In reply to Jeroen Hofstee

Cc Troy Kisky <[email protected]>

Cc Stefano Babic <[email protected]>

Signed-off-by Jeroen Hofstee <[email protected]>

---
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(-)

drivers/video/ipu_disp.c +1 -1

index cefd2dc..d5e857c 100644
@@ -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

Signature · 1 line

1.8.3.2

Anatolij Gustschin

2014-08-11 15:54 UTC #7 lore raw

PATCH v2 1/1 ] video: ipu_disp: squash clang warning

Hi,

Quoted 16 lines · On Tue, 17 Jun 2014 19:20:27 +0200 Jeroen Hofstee <[email protected]> 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 <[email protected]>
Cc Stefano Babic <[email protected]>
Signed-off-by Jeroen Hofstee <[email protected]>
---
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.

Quoted 4 lines

... 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