On Tue, Feb 15, 2022 at 09:56:50PM +0100, Andrew Lunn wrote:

quoted

quoted

quoted

-	ethernet: usbether@2 {
-		compatible = "usb0424,9730";
+	ethernet: ethernet@2 {
+		compatible = "usb424,9730";

The change of the compatible is not mentioned in the patch description.
Is this intentional?

No, I forgot to mentione it. According to the USB schema 0 should be
removed. So, this compatible was incorrect as well. With leading zero
present yaml schema was not able to detect and validate this node.

Does the current code not actually care about a leading 0? It will
match with or without it? It would be good to mention that as well in
the commit message, otherwise somebody like me is going to ask if this
breaks backwards compatibility, since normally compatible is an exact
string match.

Current kernel code do not care about exact this compatibles. There is
no driver matching against it. The USB Ethernet driver will take the
node provided by the USB core drivers without validating the compatible
against USB ID.
See:
drivers/usb/core/of.c
drivers/usb/core/message.c:2093

On other hand, DT validations tools do care about it and this nodes was
not detected automatically. I found it accidentally by grepping the
sources.

And i actually think this is the sort of change which should be as a
patch of its own. If this causes a regression, a git bisect would then
tell you if it is the change of usbether -> ethernet, or 0424 to
424. That is part of why we ask for lots of small changes.

Sounds good, I'll update it.

Regards,
Oleksij
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