Re: [PATCH v2 1/2] staging: wilc1000: fix error handling in wilc_debugfs_init()

[Greg KH]

On Thu, Jun 23, 2016 at 01:36:17PM +0100, Luis de Bethencourt wrote:
> The common format to check if a function returned an error pointer is to
> use PTR_ERR(). Instead of ERR_PTR() which is used to return said errors.
> 
> Signed-off-by: Luis de Bethencourt <luisbg@xxxxxxxxxxxxxxx>
> Reviewed-by: Julian Calaby <julian.calaby@xxxxxxxxx>
> ---
>  drivers/staging/wilc1000/wilc_debugfs.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/wilc1000/wilc_debugfs.c b/drivers/staging/wilc1000/wilc_debugfs.c
> index fcbc95d..48797dc 100644
> --- a/drivers/staging/wilc1000/wilc_debugfs.c
> +++ b/drivers/staging/wilc1000/wilc_debugfs.c
> @@ -107,7 +107,7 @@ static int __init wilc_debugfs_init(void)
>  	struct wilc_debugfs_info_t *info;
>  
>  	wilc_dir = debugfs_create_dir("wilc_wifi", NULL);
> -	if (wilc_dir ==  ERR_PTR(-ENODEV)) {
> +	if (PTR_ERR(wilc_dir) == -ENODEV) {
>  		/* it's not error. the debugfs is just not being enabled. */
>  		printk("ERR, kernel has built without debugfs support\n");
>  		return 0;

No, the best way to do this is to just ignore the return value, you
don't care about it.  It can be passed back into any debugfs calls just
fine.

So don't check the value and all is good, debugfs was written in a way
to make it _easy_ to use, no need for fancy error checking at all with
it.

thanks,

greg k-h