Re: [PATCH v3 03/11] thermal/of: Move the node pointer assignation in the OF code file

[Rafael J. Wysocki]

On Wed, Apr 29, 2026 at 6:14 PM Daniel Lezcano
<daniel.lezcano@xxxxxxxxxxxxxxxx> wrote:
>
> The node pointer being assigned to the cooling device structure is an
> action done by the thermal OF only and does not belong to the core
> framework code. Move the node pointer assignation in the thermal OF
> code. Consequently, the devm_thermal_of_cooling_device_register() can
> call its non-devm version resulting in a more intuitive design of the
> API.

I wouldn't make this change.

It adds overhead to the OF case that's not really necessary and
complicates the code just to avoid using struct device_node pointers
in the core and I'm not really convinced that passing a function
pointer to __thermal_cooling_device_register() is so much better.

> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxxxxxxxx>
> ---
>  drivers/thermal/thermal_core.c | 51 +++++++++++++++++-----------------
>  1 file changed, 26 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
> index 5c954bcae4a4..7867e6bc0a6c 100644
> --- a/drivers/thermal/thermal_core.c
> +++ b/drivers/thermal/thermal_core.c
> @@ -1040,26 +1040,11 @@ static void thermal_cooling_device_init_complete(struct thermal_cooling_device *
>                 thermal_zone_cdev_bind(tz, cdev);
>  }
>
> -/**
> - * __thermal_cooling_device_register() - register a new thermal cooling device
> - * @np:                a pointer to a device tree node.
> - * @type:      the thermal cooling device type.
> - * @devdata:   device private data.
> - * @ops:       standard thermal cooling devices callbacks.
> - *
> - * This interface function adds a new thermal cooling device (fan/processor/...)
> - * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
> - * to all the thermal zone devices registered at the same time.
> - * It also gives the opportunity to link the cooling device to a device tree
> - * node, so that it can be bound to a thermal zone created out of device tree.
> - *
> - * Return: a pointer to the created struct thermal_cooling_device or an
> - * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
> - */
>  static struct thermal_cooling_device *
> -__thermal_cooling_device_register(struct device_node *np,
> -                                 const char *type, void *devdata,
> -                                 const struct thermal_cooling_device_ops *ops)
> +__thermal_cooling_device_register(const char *type, void *devdata,
> +                                 const struct thermal_cooling_device_ops *ops,
> +                                 void (*initcb)(struct thermal_cooling_device *,
> +                                                void *), void *data)
>  {
>         struct thermal_cooling_device *cdev;
>         unsigned long current_state;
> @@ -1089,7 +1074,6 @@ __thermal_cooling_device_register(struct device_node *np,
>
>         mutex_init(&cdev->lock);
>         INIT_LIST_HEAD(&cdev->thermal_instances);
> -       cdev->np = np;
>         cdev->ops = ops;
>         cdev->updated = false;
>         cdev->device.class = &thermal_class;
> @@ -1127,6 +1111,9 @@ __thermal_cooling_device_register(struct device_node *np,
>         if (current_state <= cdev->max_state)
>                 thermal_debug_cdev_add(cdev, current_state);
>
> +       if (initcb)
> +               initcb(cdev, data);
> +
>         thermal_cooling_device_init_complete(cdev);
>
>         return cdev;
> @@ -1146,7 +1133,7 @@ __thermal_cooling_device_register(struct device_node *np,
>   * thermal_cooling_device_register() - register a new thermal cooling device
>   * @type:      the thermal cooling device type.
>   * @devdata:   device private data.
> - * @ops:               standard thermal cooling devices callbacks.
> + * @ops:       standard thermal cooling devices callbacks.
>   *
>   * This interface function adds a new thermal cooling device (fan/processor/...)
>   * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
> @@ -1159,10 +1146,17 @@ struct thermal_cooling_device *
>  thermal_cooling_device_register(const char *type, void *devdata,
>                                 const struct thermal_cooling_device_ops *ops)
>  {
> -       return __thermal_cooling_device_register(NULL, type, devdata, ops);
> +       return __thermal_cooling_device_register(type, devdata, ops, NULL, NULL);
>  }
>  EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
>
> +static void thermal_of_cooling_device_init(struct thermal_cooling_device *cdev, void *data)
> +{
> +       struct device_node *np = data;
> +
> +       cdev->np = np;
> +}
> +
>  /**
>   * thermal_of_cooling_device_register() - register an OF thermal cooling device
>   * @np:                a pointer to a device tree node.
> @@ -1183,7 +1177,14 @@ thermal_of_cooling_device_register(struct device_node *np,
>                                    const char *type, void *devdata,
>                                    const struct thermal_cooling_device_ops *ops)
>  {
> -       return __thermal_cooling_device_register(np, type, devdata, ops);
> +       struct thermal_cooling_device *cdev;
> +
> +       cdev = __thermal_cooling_device_register(type, devdata, ops,
> +                                                thermal_of_cooling_device_init, np);
> +       if (IS_ERR(cdev))
> +               return cdev;
> +
> +       return cdev;
>  }
>  EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
>
> @@ -1217,7 +1218,7 @@ devm_thermal_cooling_device_register(struct device *dev,
>         struct thermal_cooling_device *cdev;
>         int ret;
>
> -       cdev = __thermal_cooling_device_register(NULL, type, devdata, ops);
> +       cdev = thermal_cooling_device_register(type, devdata, ops);
>         if (IS_ERR(cdev))
>                 return cdev;
>
> @@ -1255,7 +1256,7 @@ devm_thermal_of_cooling_device_register(struct device *dev,
>         struct thermal_cooling_device *cdev;
>         int ret;
>
> -       cdev = __thermal_cooling_device_register(np, type, devdata, ops);
> +       cdev = thermal_of_cooling_device_register(np, type, devdata, ops);
>         if (IS_ERR(cdev))
>                 return cdev;
>
> --
> 2.43.0
>