# Re: \[PATCH v5 3/7\] of: Warn if of\_graph\_get\_next\_endpoint is called with the root node

- From: Sylwester Nawrocki \<hidden\>
- Date: 2014-02-28 21:09:34 
- List: linux-devicetree
- Page: https://ratatoskr.run/linux-devicetree/2014/02/4209129
- Thread: https://ratatoskr.run/linux-media/2014/02/4208317/t.md

```text
On 02/27/2014 06:35 PM, Philipp Zabel wrote:
> If of_graph_get_next_endpoint is given a parentless node instead of an
> endpoint node, it is clearly a bug.
>
> Signed-off-by: Philipp Zabel<p.zabel@pengutronix.de>
> ---
>   drivers/of/base.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index b2f223f..6e650cf 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -2028,8 +2028,8 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
>   		of_node_put(node);
>   	} else {
>   		port = of_get_parent(prev);
> -		if (!port)
> -			/* Hm, has someone given us the root node ?... */
> +		if (WARN_ONCE(!port, "%s(): endpoint has no parent node\n",
> +			      __func__))

Perhaps we can add more information to this error log, e.g.

		if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
			      __func__, prev->full_name))
?
>   			return NULL;
>
>   		/* Avoid dropping prev node refcount to 0. */
```