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

[Douglas Anderson]

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>
---

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