Re: [PATCH v2 1/3] usb: core: Don't force USB generic_subclass drivers to define probe()

[Alan Stern]

On Fri, Dec 01, 2023 at 10:29:50AM -0800, Douglas Anderson wrote:
> There's no real reason that subclassed USB drivers _need_ to define
> probe() since they might want to subclass for some other reason. Make
> it optional to define probe() if we're a generic_subclass.
> 
> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---

Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

> Changes in v2:
> - ("Don't force USB generic_subclass drivers to define ...") new for v2.
> 
>  drivers/usb/core/driver.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
> index f58a0299fb3b..1dc0c0413043 100644
> --- a/drivers/usb/core/driver.c
> +++ b/drivers/usb/core/driver.c
> @@ -290,7 +290,10 @@ static int usb_probe_device(struct device *dev)
>  	 * specialised device drivers prior to setting the
>  	 * use_generic_driver bit.
>  	 */
> -	error = udriver->probe(udev);
> +	if (udriver->probe)
> +		error = udriver->probe(udev);
> +	else if (!udriver->generic_subclass)
> +		error = -EINVAL;
>  	if (error == -ENODEV && udriver != &usb_generic_driver &&
>  	    (udriver->id_table || udriver->match)) {
>  		udev->use_generic_driver = 1;
> -- 
> 2.43.0.rc2.451.g8631bc7472-goog
>