[PATCH v2] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns

[PATCH v2] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns

[Dan Carpenter]

Static analysis tools complain about the -EINVAL error code being
stored in an unsigned variable.  Let's change this to match
the clk_get_rate() function which is type unsigned long and returns
zero on error.

Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
v2: In v1 I change the type to int which was wrong.  This is a different
    approach.  CC the freedreno list this time too.

 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4 ++--
 drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 0e7a68714e9e..25e6a15eaf9f 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -979,13 +979,13 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
 	return 0;
 }
 
-u64 dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
+unsigned long dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
 {
 	struct clk *clk;
 
 	clk = msm_clk_bulk_get_clock(dpu_kms->clocks, dpu_kms->num_clocks, clock_name);
 	if (!clk)
-		return -EINVAL;
+		return 0;
 
 	return clk_get_rate(clk);
 }
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
index aca39a4689f4..961918e5a5b3 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
@@ -201,6 +201,6 @@ void dpu_disable_vblank(struct msm_kms *kms, struct drm_crtc *crtc);
  *
  * Return: current clock rate
  */
-u64 dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name);
+unsigned long dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name);
 
 #endif /* __dpu_kms_H__ */
-- 
2.39.2

Re: [PATCH v2] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns

[Abhinav Kumar]

On 5/26/2023 4:51 AM, Dan Carpenter wrote:
> Static analysis tools complain about the -EINVAL error code being
> stored in an unsigned variable.  Let's change this to match
> the clk_get_rate() function which is type unsigned long and returns
> zero on error.
> 
> Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> v2: In v1 I change the type to int which was wrong.  This is a different
>      approach.  CC the freedreno list this time too.
> 
>   drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4 ++--
>   drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 2 +-
>   2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index 0e7a68714e9e..25e6a15eaf9f 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -979,13 +979,13 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
>   	return 0;
>   }
>   
> -u64 dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
> +unsigned long dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
>   {
>   	struct clk *clk;
>   
>   	clk = msm_clk_bulk_get_clock(dpu_kms->clocks, dpu_kms->num_clocks, clock_name);
>   	if (!clk)
> -		return -EINVAL;
> +		return 0;
>   

Currently, the only caller of this API is 
dpu_encoder_phys_cmd_tearcheck_config which seems to handle <=0 so this 
change should be fine. Hence


Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

Re: [PATCH v2] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns

[Dmitry Baryshkov]

On Fri, 26 May 2023 14:51:59 +0300, Dan Carpenter wrote:
> Static analysis tools complain about the -EINVAL error code being
> stored in an unsigned variable.  Let's change this to match
> the clk_get_rate() function which is type unsigned long and returns
> zero on error.
> 
> 

Applied, thanks!

[1/1] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns
      https://gitlab.freedesktop.org/lumag/msm/-/commit/025e3d97867c

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Re: [PATCH v2] drm/msm/dpu: clean up dpu_kms_get_clk_rate() returns

[Marijn Suijten]

On 2023-05-26 14:51:59, Dan Carpenter wrote:
> Static analysis tools complain about the -EINVAL error code being
> stored in an unsigned variable.  Let's change this to match
> the clk_get_rate() function which is type unsigned long and returns
> zero on error.
> 
> Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> v2: In v1 I change the type to int which was wrong.  This is a different
>     approach.  CC the freedreno list this time too.

Just like v1, should we clean up the <= in
dpu_encoder_phys_cmd_tearcheck_config (to just `if (!vsync_hz)`),
because doing a <=0 on a u32 has a more limited meaning?

> 
>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 4 ++--
>  drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 2 +-
>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index 0e7a68714e9e..25e6a15eaf9f 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -979,13 +979,13 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
>  	return 0;
>  }
>  
> -u64 dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
> +unsigned long dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name)
>  {
>  	struct clk *clk;
>  
>  	clk = msm_clk_bulk_get_clock(dpu_kms->clocks, dpu_kms->num_clocks, clock_name);
>  	if (!clk)
> -		return -EINVAL;
> +		return 0;
>  
>  	return clk_get_rate(clk);
>  }
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> index aca39a4689f4..961918e5a5b3 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
> @@ -201,6 +201,6 @@ void dpu_disable_vblank(struct msm_kms *kms, struct drm_crtc *crtc);
>   *
>   * Return: current clock rate

Or 0 if this clock is not available/present.

- Marijn

>   */
> -u64 dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name);
> +unsigned long dpu_kms_get_clk_rate(struct dpu_kms *dpu_kms, char *clock_name);
>  
>  #endif /* __dpu_kms_H__ */
> -- 
> 2.39.2
>