Re: [PATCH] soc: qcom: smsm: fix child-node lookup

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Wed 15 Nov 03:07 PST 2017, 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.
> 
> Note that the original premature free of the parent node has already
> been fixed separately.
> 
> Also note that this pattern of looking up the first child node with a
> given property is rare enough that a generic helper is probably not
> warranted.
> 

I agree.

> Fixes: c97c4090ff72 ("soc: qcom: smsm: Add driver for Qualcomm SMSM")
> Fixes: 3e8b55411468 ("soc: qcom: smsm: fix of_node refcnting problem")
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Rob Clark <robdclark@gmail.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Thanks,
Bjorn

> ---
>  drivers/soc/qcom/smsm.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/soc/qcom/smsm.c b/drivers/soc/qcom/smsm.c
> index 403bea9d546b..50214b620865 100644
> --- a/drivers/soc/qcom/smsm.c
> +++ b/drivers/soc/qcom/smsm.c
> @@ -496,8 +496,10 @@ static int qcom_smsm_probe(struct platform_device *pdev)
>  	if (!smsm->hosts)
>  		return -ENOMEM;
>  
> -	local_node = of_find_node_with_property(of_node_get(pdev->dev.of_node),
> -						"#qcom,smem-state-cells");
> +	for_each_child_of_node(pdev->dev.of_node, local_node) {
> +		if (of_find_property(local_node, "#qcom,smem-state-cells", NULL))
> +			break;
> +	}
>  	if (!local_node) {
>  		dev_err(&pdev->dev, "no state entry\n");
>  		return -EINVAL;
> -- 
> 2.15.0
>