Re: [PATCH] watchdog: w83877f_wdt: Mark expected switch fall-through

[Guenter Roeck <linux@roeck-us.net>]

On Tue, Feb 26, 2019 at 01:07:43PM -0600, Gustavo A. R. Silva wrote:
> In preparation to enabling -Wimplicit-fallthrough, mark switch
> cases where we are expecting to fall through.
> 
> This patch fixes the following warning:
> 
> drivers/watchdog/w83877f_wdt.c: In function ‘fop_ioctl’:
> drivers/watchdog/w83877f_wdt.c:294:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
>    wdt_keepalive();
>    ^~~~~~~~~~~~~~~
> drivers/watchdog/w83877f_wdt.c:297:2: note: here
>   case WDIOC_GETTIMEOUT:
>   ^~~~
> 
> Warning level 3 was used: -Wimplicit-fallthrough=3
> 
> Notice that, in this particular case, the code comment is modified
> in accordance with what GCC is expecting to find.
> 
> This patch is part of the ongoing efforts to enable
> -Wimplicit-fallthrough.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/watchdog/w83877f_wdt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/watchdog/w83877f_wdt.c b/drivers/watchdog/w83877f_wdt.c
> index 05658ecc0aa4..db9b6488e388 100644
> --- a/drivers/watchdog/w83877f_wdt.c
> +++ b/drivers/watchdog/w83877f_wdt.c
> @@ -292,8 +292,8 @@ static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
>  
>  		timeout = new_timeout;
>  		wdt_keepalive();
> -		/* Fall through */
>  	}
> +		/* Fall through */
>  	case WDIOC_GETTIMEOUT:
>  		return put_user(timeout, p);
>  	default:
> -- 
> 2.21.0
>