Re: [PATCH v3 1/2] dt-bindings: usb: Add the binding example for the Genesys Logic GL3523 hub

From: Anand Moon
Date: Tue Nov 21 2023 - 21:21:27 EST


Hi Conor

On Tue, 21 Nov 2023 at 22:30, Conor Dooley <conor@xxxxxxxxxx> wrote:
>
> On Tue, Nov 21, 2023 at 09:36:37AM +0530, Anand Moon wrote:
> > On Mon, 20 Nov 2023 at 21:15, Conor Dooley <conor@xxxxxxxxxx> wrote:
> > > On Sun, Nov 19, 2023 at 08:57:28PM +0530, Anand Moon wrote:
> > > > On Sun, 19 Nov 2023 at 19:28, Conor Dooley <conor@xxxxxxxxxx> wrote:
> > > > > On Sun, Nov 19, 2023 at 08:04:50AM +0530, Anand Moon wrote:
> > > > > > Add the binding example for the USB3.1 Genesys Logic GL3523
> > > > > > integrates with USB 3.1 Gen 1 Super Speed and USB 2.0 High-Speed
> > > > > > hub.
> > > > >
> > > > > But no comment in the commit message about the new property for the
> > > > > "peer hub". $subject saying "dt-bindings: usb: Add the binding example
> > > > > for the Genesys Logic GL3523 hub" is misleading when the meaningful
> > > > > parts of the patch are unrelated to the example.
> > > > >
>
> > > > > > + peer-hub:
> > > > > > + $ref: /schemas/types.yaml#/definitions/phandle
> > > > > > + description:
> > > > > > + phandle to the peer hub on the controller.
> > > > >
> > > > > What is this, why is it needed? Please explain it in your commit
> > > > > message.
> > > > >
> > > > Ok, GL3523 integrates Genesys Logic self-developed USB 3.1 Gen 1
> > > > Super Speed transmitter/receiver physical layer (PHY) and USB 2.0
> > > > High-Speed PHY
> > > >
> > > > peer-hub is used to cross-connect those phy nodes so that it can help
> > > > hub power on/off simultaneously.
> > >
> > > I said please explain it in your commit message, but on reflection I
> > > think that would be insufficient. Extending the description to explain
> > > what the peer-hub is would be great too. "peer hub on the controller"
> > > doesn't seem to make sense to me either, as the peer hub phandle is to
> > > another phy, not to the controller. I think that would probably also be
> > > resolved by explaining what the peer hub is in a more detailed manner.
> > >
> > > If this is purely a genesys thing, the property should grow a genesys,
> > > prefix also.
> > >
> > No, some USB Hub have combined phy for USB 3.x and USB 2.0 and have common
> > reset-gpios and power supply, peer-hub node helps connect the USB controller and
> > bring up the USB hub.
>
> I don't know what this is a response to.
>

This was the response to your comment, it is a generic property
"If this is purely a genesys thing, the property should grow a genesys,"

Please find the link to the schematic of the board which shares the
details of the binding example. USB_HUB_GL3523.

https://dn.odroid.com/S922X/ODROID-N2/Schematic/odroid-n2_rev0.6_20210121.pdf

> > I was waiting for more feedback on these changes.
> > Once it's ok I will update with proper the commit message in v4.
>
> And the property description too, so that a reader can understand how to
> implement it.

Yes, I will do that.

>
> Cheers,
> Conor.

Thanks
-Anand