Re: [PATCH v3 2/6] thermal: of: Use scoped device node handling to simplify thermal_of_trips_init()

[Jonathan Cameron]

On Tue, 08 Oct 2024 11:00:02 +0200
Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> wrote:

> Obtain the device node reference with scoped/cleanup.h to reduce error
> handling and make the code a bit simpler.
> 
> Reviewed-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
A follow up suggestion below.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

> 
> ---
> 
> Changes in v2:
> 1. Drop left-over of_node_put in regular exit path (Chen-Yu)
> ---
>  drivers/thermal/thermal_of.c | 16 ++++------------
>  1 file changed, 4 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
> index f0ffc0e335ba9406f4fd858d6c561f9d23f4b842..d7d6f62caa13d545e5f7fae4c8ac1e737bf4c4b1 100644
> --- a/drivers/thermal/thermal_of.c
> +++ b/drivers/thermal/thermal_of.c
> @@ -96,10 +96,9 @@ static int thermal_of_populate_trip(struct device_node *np,
>  static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *ntrips)
>  {
>  	struct thermal_trip *tt;
> -	struct device_node *trips;
>  	int ret, count;
>  
> -	trips = of_get_child_by_name(np, "trips");
> +	struct device_node *trips __free(device_node) = of_get_child_by_name(np, "trips");
>  	if (!trips) {
>  		pr_err("Failed to find 'trips' node\n");
>  		return ERR_PTR(-EINVAL);
> @@ -108,15 +107,12 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
>  	count = of_get_child_count(trips);
>  	if (!count) {
>  		pr_err("No trip point defined\n");
> -		ret = -EINVAL;
> -		goto out_of_node_put;
> +		return ERR_PTR(-EINVAL);
>  	}
>  
>  	tt = kzalloc(sizeof(*tt) * count, GFP_KERNEL);
> -	if (!tt) {
> -		ret = -ENOMEM;
> -		goto out_of_node_put;
> -	}
> +	if (!tt)
> +		return ERR_PTR(-ENOMEM);
>  
>  	*ntrips = count;
>  
> @@ -127,15 +123,11 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
>  			goto out_kfree;
>  	}
>  
> -	of_node_put(trips);
> -
>  	return tt;
>  
>  out_kfree:
>  	kfree(tt);
May be worth a follow up to do __free(kfree) on this + a steal for the return.
Then push the ntrips set until after the populate so it doesn't need resetting to 0.


>  	*ntrips = 0;
> -out_of_node_put:
> -	of_node_put(trips);
>  
>  	return ERR_PTR(ret);
>  }
>