Re: [PATCH 2/2] mfd: twl6040: fix child-node lookup

From: Peter Ujfalusi
Date: Mon Nov 13 2017 - 15:15:46 EST


On 11/11/2017 05:38 PM, Johan Hovold wrote:
> Fix child-node lookup during probe, which ended up searching the whole
> device tree depth-first starting at the parent rather than just matching
> on its children.
>
> To make things worse, the parent node was prematurely freed, while the
> child node was leaked.
>
> Note that the CONFIG_OF compile guard can be removed as
> of_get_child_by_name() provides a !CONFIG_OF implementation which always
> fails.

Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>

>
> Fixes: 37e13cecaa14 ("mfd: Add support for Device Tree to twl6040")
> Fixes: ca2cad6ae38e ("mfd: Fix twl6040 build failure")
> Cc: stable <stable@xxxxxxxxxxxxxxx> # 3.5
> Cc: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> Cc: Samuel Ortiz <sameo@xxxxxxxxxxxxxxx>
> ---
> drivers/mfd/twl6040.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mfd/twl6040.c b/drivers/mfd/twl6040.c
> index d66502d36ba0..dd19f17a1b63 100644
> --- a/drivers/mfd/twl6040.c
> +++ b/drivers/mfd/twl6040.c
> @@ -97,12 +97,16 @@ static struct reg_sequence twl6040_patch[] = {
> };
>
>
> -static bool twl6040_has_vibra(struct device_node *node)
> +static bool twl6040_has_vibra(struct device_node *parent)
> {
> -#ifdef CONFIG_OF
> - if (of_find_node_by_name(node, "vibra"))
> + struct device_node *node;
> +
> + node = of_get_child_by_name(parent, "vibra");
> + if (node) {
> + of_node_put(node);
> return true;
> -#endif
> + }
> +
> return false;
> }
>
>


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PÃter

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