[PATCH] backlight: change the return type of backlight_update_status() to int

[PATCH] backlight: change the return type of backlight_update_status() to int

[Hyungwon Hwang]

Backlight device returns the result of update_status(), but
backlight_update_status() ignores it. So the consumers cannot confirm the
result of their function call. This patch makes the result to be returned
back for consumers.

Signed-off-by: Hyungwon Hwang <human.hwang@samsung.com>
---
 include/linux/backlight.h | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index adb14a8..1e7a69a 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -117,12 +117,16 @@ struct backlight_device {
 	int use_count;
 };
 
-static inline void backlight_update_status(struct backlight_device *bd)
+static inline int backlight_update_status(struct backlight_device *bd)
 {
+	int ret = -ENOENT;
+
 	mutex_lock(&bd->update_lock);
 	if (bd->ops && bd->ops->update_status)
-		bd->ops->update_status(bd);
+		ret = bd->ops->update_status(bd);
 	mutex_unlock(&bd->update_lock);
+
+	return ret;
 }
 
 extern struct backlight_device *backlight_device_register(const char *name,
-- 
1.9.1

Re: [PATCH] backlight: change the return type of backlight_update_status() to int

[Jingoo Han]

On Thursday, May 28, 2015 4:25 PM, Hyungwon Hwang wrote:
> 
> Backlight device returns the result of update_status(), but
> backlight_update_status() ignores it. So the consumers cannot confirm the
> result of their function call. This patch makes the result to be returned
> back for consumers.
> 
> Signed-off-by: Hyungwon Hwang <human.hwang@samsung.com>

Acked-by: Jingoo Han <jingoohan1@gmail.com>

> ---
>  include/linux/backlight.h | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> index adb14a8..1e7a69a 100644
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -117,12 +117,16 @@ struct backlight_device {
>  	int use_count;
>  };
> 
> -static inline void backlight_update_status(struct backlight_device *bd)
> +static inline int backlight_update_status(struct backlight_device *bd)
>  {
> +	int ret = -ENOENT;
> +
>  	mutex_lock(&bd->update_lock);
>  	if (bd->ops && bd->ops->update_status)
> -		bd->ops->update_status(bd);
> +		ret = bd->ops->update_status(bd);
>  	mutex_unlock(&bd->update_lock);
> +
> +	return ret;
>  }
> 
>  extern struct backlight_device *backlight_device_register(const char *name,
> --
> 1.9.1

Re: [PATCH] backlight: change the return type of backlight_update_status() to int

[Lee Jones]

On Thu, 28 May 2015, Hyungwon Hwang wrote:

> Backlight device returns the result of update_status(), but
> backlight_update_status() ignores it. So the consumers cannot confirm the
> result of their function call. This patch makes the result to be returned
> back for consumers.
> 
> Signed-off-by: Hyungwon Hwang <human.hwang@samsung.com>
> ---
>  include/linux/backlight.h | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)

Applied with Jingoo's Ack, thanks.

> diff --git a/include/linux/backlight.h b/include/linux/backlight.h
> index adb14a8..1e7a69a 100644
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -117,12 +117,16 @@ struct backlight_device {
>  	int use_count;
>  };
>  
> -static inline void backlight_update_status(struct backlight_device *bd)
> +static inline int backlight_update_status(struct backlight_device *bd)
>  {
> +	int ret = -ENOENT;
> +
>  	mutex_lock(&bd->update_lock);
>  	if (bd->ops && bd->ops->update_status)
> -		bd->ops->update_status(bd);
> +		ret = bd->ops->update_status(bd);
>  	mutex_unlock(&bd->update_lock);
> +
> +	return ret;
>  }
>  
>  extern struct backlight_device *backlight_device_register(const char *name,

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
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