Re: [PATCH v1 1/2] platform/x86: dell/dell-rbtn: Register ACPI notify handler directly

[Ilpo Järvinen]

On Thu, 12 Mar 2026, Rafael J. Wysocki wrote:

> From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx>
> 
> To facilitate subsequent conversion of the driver to a platform one,
> make it install an ACPI notify handler directly instead of using
> a .notify() callback in struct acpi_driver.
> 
> No intentional functional impact.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>  drivers/platform/x86/dell/dell-rbtn.c | 50 ++++++++++++++++++---------
>  1 file changed, 33 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/dell-rbtn.c b/drivers/platform/x86/dell/dell-rbtn.c
> index a415c432d4c3..9271b27abb46 100644
> --- a/drivers/platform/x86/dell/dell-rbtn.c
> +++ b/drivers/platform/x86/dell/dell-rbtn.c
> @@ -207,7 +207,7 @@ static void rbtn_input_event(struct rbtn_data *rbtn_data)
>  
>  static int rbtn_add(struct acpi_device *device);
>  static void rbtn_remove(struct acpi_device *device);
> -static void rbtn_notify(struct acpi_device *device, u32 event);
> +static void rbtn_notify(acpi_handle handle, u32 event, void *data);
>  
>  static const struct acpi_device_id rbtn_ids[] = {
>  	{ "DELRBTN", 0 },
> @@ -293,7 +293,6 @@ static struct acpi_driver rbtn_driver = {
>  	.ops = {
>  		.add = rbtn_add,
>  		.remove = rbtn_remove,
> -		.notify = rbtn_notify,
>  	},
>  };
>  
> @@ -382,6 +381,22 @@ EXPORT_SYMBOL_GPL(dell_rbtn_notifier_unregister);
>   * acpi driver functions
>   */
>  
> +static void rbtn_cleanup(struct acpi_device *device)
> +{
> +	struct rbtn_data *rbtn_data = device->driver_data;
> +
> +	switch (rbtn_data->type) {
> +	case RBTN_TOGGLE:
> +		rbtn_input_exit(rbtn_data);
> +		break;
> +	case RBTN_SLIDER:
> +		rbtn_rfkill_exit(device);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
>  static int rbtn_add(struct acpi_device *device)
>  {
>  	struct rbtn_data *rbtn_data;
> @@ -422,31 +437,32 @@ static int rbtn_add(struct acpi_device *device)
>  		break;
>  	}
>  	if (ret)
> -		rbtn_acquire(device, false);
> +		goto err;
> +
> +	ret = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
> +					      rbtn_notify, device);
> +	if (ret) {
> +		rbtn_cleanup(device);

If you add(/have) a rollback path, please put all rollbacks there unless 
there is a good reason not to (making a setup call that makes the rollback 
non-linear).

-- 
 i.


> +		goto err;
> +	}
>  
> +	return 0;
> +
> +err:
> +	rbtn_acquire(device, false);
>  	return ret;
>  }
>  
>  static void rbtn_remove(struct acpi_device *device)
>  {
> -	struct rbtn_data *rbtn_data = device->driver_data;
> -
> -	switch (rbtn_data->type) {
> -	case RBTN_TOGGLE:
> -		rbtn_input_exit(rbtn_data);
> -		break;
> -	case RBTN_SLIDER:
> -		rbtn_rfkill_exit(device);
> -		break;
> -	default:
> -		break;
> -	}
> -
> +	acpi_dev_remove_notify_handler(device, ACPI_DEVICE_NOTIFY, rbtn_notify);
> +	rbtn_cleanup(device);
>  	rbtn_acquire(device, false);
>  }
>  
> -static void rbtn_notify(struct acpi_device *device, u32 event)
> +static void rbtn_notify(acpi_handle handle, u32 event, void *data)
>  {
> +	struct acpi_device *device = data;
>  	struct rbtn_data *rbtn_data = device->driver_data;
>  
>  	/*
>