Re: [PATCH net-next 2/8] dt-bindings: net: lan9645x: add LAN9645X switch bindings

On Thu, 2026-03-05 at 18:31 +0000, Conor Dooley wrote:

On Thu, Mar 05, 2026 at 01:57:37PM +0100, Jens Emil Schulz Ostergaard wrote:

quoted

On Tue, 2026-03-03 at 19:04 +0000, Conor Dooley wrote:

quoted

On Tue, Mar 03, 2026 at 03:18:45PM +0100, Andrew Lunn wrote:

quoted

quoted

+        properties:
+          microchip,led-drive-mode:
+            $ref: /schemas/types.yaml#/definitions/uint32
+            description: |
+              Set the LED drive mode for the copper PHY associated with
+              this port.
+
+                0 - LED1 and LED2 in open-drain mode
+                1 - LED1 in active drive mode (can be used for single-LED
+                    configurations requiring active drive)
+                2 - Reserved
+                3 - LED1 and LED2 in active drive mode
+            minimum: 0
+            maximum: 3

I doubt the DT Maintainers will accept that. This looks a lot like a
value you write into a register. How are active drive and open-drain
described in other DT bindings? Is there something you can reuse?

I had a quick look and I didn't see anything really that stood out to me
that would be a drop-in replacement.
I also tried looking in the datasheet for more information on these
modes, but I couldn't see anything obvious. For example, there were zero
hits for "drain" in either LAN9645xS or LAN9645xF datasheets.

That said, yea you're right about DT maintainer feelings about it.
There's a couple things I could suggest, but I'd like to know about what
mode 1 means for LED2 first. If there's actually nothing similar, what
about representing each led with a child node and having open-drain be
the default with a property in the child for active-drive?

quoted

For 1, what happens to LED2? Not used at all?

In mode 1 LED2 will be open-drain. This mode only makes sense if you have
just 1 LED. With two LEDs mode 0 or mode 3 should be used.

Could we then have child nodes for each led, and have a property in each
that sets the mode to either open-drain or active-drive? Or am I just
inserting complexity by asking for that?

I think it sounds sensible, I will add this.

Thanks,
Emil