[PATCH v2] video: fbdev: Fix Warning comparing pointer to 0 reported by coccicheck

[Mathieu Malaterre]

On Mon, Jun 3, 2019 at 1:21 PM <shobhitkukreti at gmail.com> wrote:
>
> From: Shobhit Kukreti <shobhitkukreti at gmail.com>
>
> Fixed Warning Comparing Pointer to 0. Changed return value to -ENOMEM to
> report kzalloc failure
>
> drivers/video/fbdev/controlfb.c: WARNING comparing pointer to 0
> drivers/video/fbdev/controlfb.c: WARNING comparing pointer to 0
> drivers/video/fbdev/controlfb.c: WARNING comparing pointer to 0
>
> Signed-off-by: Shobhit Kukreti <shobhitkukreti at gmail.com>
> ---
> Changes in v2:
>  - Modified commit message to report change in return type
>
>  drivers/video/fbdev/controlfb.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/video/fbdev/controlfb.c b/drivers/video/fbdev/controlfb.c
> index 7af8db2..07907c5 100644
> --- a/drivers/video/fbdev/controlfb.c
> +++ b/drivers/video/fbdev/controlfb.c
> @@ -182,7 +182,7 @@ int init_module(void)
>         int ret = -ENXIO;
>
>         dp = of_find_node_by_name(NULL, "control");
> -       if (dp != 0 && !control_of_init(dp))
> +       if (dp != NULL && !control_of_init(dp))
>                 ret = 0;
>         of_node_put(dp);
>
> @@ -580,7 +580,7 @@ static int __init control_init(void)
>         control_setup(option);
>
>         dp = of_find_node_by_name(NULL, "control");
> -       if (dp != 0 && !control_of_init(dp))
> +       if (dp != NULL && !control_of_init(dp))
>                 ret = 0;
>         of_node_put(dp);
>
> @@ -683,8 +683,8 @@ static int __init control_of_init(struct device_node *dp)
>                 return -ENXIO;
>         }
>         p = kzalloc(sizeof(*p), GFP_KERNEL);
> -       if (p == 0)
> -               return -ENXIO;
> +       if (p == NULL)

nit: I would have use `!p` (same for the others above). Maybe
checkpatch with --strict would warn for those (can't remember from top
of my head).

Anyway:

Reviewed-by: Mathieu Malaterre <malat at debian.org>

> +               return -ENOMEM;
>         control_fb = p; /* save it for cleanups */
>
>         /* Map in frame buffer and registers */
> --
> 2.7.4
>