Re: [PATCH v2 1/3] watchdog: s3c2410: Constify local structures

[Guenter Roeck]

On 03/11/2017 09:42 AM, Krzysztof Kozlowski wrote:
> Structures watchdog_device, watchdog_ops and s3c2410_wdt_variant are not
> modified so they can be made const to increase code safeness.
>
> Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> ---
>  drivers/watchdog/s3c2410_wdt.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
> index 6ed97596ca80..5eaec319e499 100644
> --- a/drivers/watchdog/s3c2410_wdt.c
> +++ b/drivers/watchdog/s3c2410_wdt.c
> @@ -131,7 +131,7 @@ struct s3c2410_wdt {
>  	unsigned long		wtdat_save;
>  	struct watchdog_device	wdt_device;
>  	struct notifier_block	freq_transition;
> -	struct s3c2410_wdt_variant *drv_data;
> +	const struct s3c2410_wdt_variant *drv_data;
>  	struct regmap *pmureg;
>  };
>
> @@ -401,7 +401,7 @@ static const struct watchdog_ops s3c2410wdt_ops = {
>  	.restart = s3c2410wdt_restart,
>  };
>
> -static struct watchdog_device s3c2410_wdd = {
> +static const struct watchdog_device s3c2410_wdd = {
>  	.info = &s3c2410_wdt_ident,
>  	.ops = &s3c2410wdt_ops,
>  	.timeout = S3C2410_WATCHDOG_DEFAULT_TIME,
> @@ -507,15 +507,15 @@ static inline unsigned int s3c2410wdt_get_bootstatus(struct s3c2410_wdt *wdt)
>  	return 0;
>  }
>
> -static inline struct s3c2410_wdt_variant *
> +static inline const struct s3c2410_wdt_variant *
>  s3c2410_get_wdt_drv_data(struct platform_device *pdev)
>  {
>  	if (pdev->dev.of_node) {
>  		const struct of_device_id *match;
>  		match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node);
> -		return (struct s3c2410_wdt_variant *)match->data;
> +		return (const struct s3c2410_wdt_variant *)match->data;

The const in this typecast isn't necessary.

>  	} else {
> -		return (struct s3c2410_wdt_variant *)
> +		return (const struct s3c2410_wdt_variant *)

Same here. Transition to const is automatic.

>  			platform_get_device_id(pdev)->driver_data;
>  	}
>  }