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

Alan Stern
2023-12-01T19:28:46Z

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@chromium.org>
> ---

Reviewed-by: Alan Stern <stern@rowland.harvard.edu>

> 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
>