Re: [PATCH 02/17] Input: serio - attach manual drivers through the driver core

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Thu, Nov 05, 2026 at 01:42:15PM +0200, Leon Romanovsky wrote:
> From: Leon Romanovsky <leonro@nvidia.com>
> 
> Manual serio binding connects a driver before driver core can admit the
> device. A rejected binding therefore arrives after functional setup.
> 
> Keep the port ID check and use device_driver_attach() for the existing bus
> probe path. Driver core then serializes admission and handles probe failure
> before publishing the binding.
> 
> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>  drivers/input/serio/serio.c | 24 +++---------------------
>  1 file changed, 3 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
> index 54dd26249b027..604440244c1ca 100644
> --- a/drivers/input/serio/serio.c
> +++ b/drivers/input/serio/serio.c
> @@ -81,28 +81,10 @@ static int serio_match_port(const struct serio_device_id *ids, struct serio *ser
>  
>  static int serio_bind_driver(struct serio *serio, struct serio_driver *drv)
>  {
> -	int error;
> -
> -	if (serio_match_port(drv->id_table, serio)) {
> -
> -		serio->dev.driver = &drv->driver;
> -		if (serio_connect_driver(serio, drv)) {
> -			serio->dev.driver = NULL;
> -			return -ENODEV;
> -		}
> +	if (!serio_match_port(drv->id_table, serio))
> +		return 0;
>  
> -		error = device_bind_driver(&serio->dev);
> -		if (error) {
> -			dev_warn(&serio->dev,
> -				 "device_bind_driver() failed for %s (%s) and %s, error: %d\n",
> -				 serio->phys, serio->name,
> -				 drv->description, error);
> -			serio_disconnect_driver(serio);
> -			serio->dev.driver = NULL;
> -			return error;
> -		}
> -	}
> -	return 0;
> +	return device_driver_attach(&drv->driver, &serio->dev);

I am not sure how safe it is, serio (and gameport) have pretty elaborate
structure and locking rules because they can recurse into themselves (to
support case of Synaptics touch-pads with pass-through PS/2 ports).

But this call is for user-initiated probing anyways, I am not sure if it
even needs "trust" handling.

... And I even thinking if we really need to keep these custom
attributes or if I can rip them out in the future ...

Thanks.

-- 
Dmitry