Re: [PATCH v4 19/35] platform/x86/dell/dell-rbtn: Move handler installing logic to driver

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Thu, 1 Jun 2023, Michal Wilczynski wrote:

> Currently logic for installing notifications from ACPI devices is
> implemented using notify callback in struct acpi_driver. Preparations
> are being made to replace acpi_driver with more generic struct
> platform_driver, which doesn't contain notify callback. Furthermore
> as of now handlers are being called indirectly through
> acpi_notify_device(), which decreases performance.
> 
> Call acpi_device_install_event_handler() at the end of .add() callback.
> Call acpi_device_remove_event_handler() at the beginning of .remove()
> callback. Change arguments passed to the notify callback to match with
> what's required by acpi_device_install_event_handler().
> 
> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
> ---
>  drivers/platform/x86/dell/dell-rbtn.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/dell-rbtn.c b/drivers/platform/x86/dell/dell-rbtn.c
> index aa0e6c907494..4dcad59eb035 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,
>  	},
>  	.owner = THIS_MODULE,
>  };
> @@ -422,7 +421,10 @@ static int rbtn_add(struct acpi_device *device)
>  		ret = -EINVAL;
>  	}
>  
> -	return ret;
> +	if (ret)
> +		return ret;
> +
> +	return acpi_device_install_event_handler(device, ACPI_DEVICE_NOTIFY, rbtn_notify);

What about the other things that are done in rbtn_remove(), should you 
rollback more?

I suspect there's a pre-existing lack of rbtn_acquire(device, false); 
here to begin with.

-- 
 i.