Re: [net-next PATCH v3 4/5] net: phy: Introduce fwnode_get_phy_id()

From: Calvin Johnson
Date: Mon May 11 2020 - 03:39:31 EST


On Fri, May 08, 2020 at 05:48:33PM -0500, Jeremy Linton wrote:
> Hi,
>
> On 5/8/20 3:27 PM, Andrew Lunn wrote:
> > > > There is a very small number of devices where the vendor messed up,
> > > > and did not put valid contents in the ID registers. In such cases, we
> > > > can read the IDs from device tree. These are then used in exactly the
> > > > same way as if they were read from the device.
> > > >
> > >
> > > Is that the case here?
> >
> > Sorry, I don't understand the question?
>
> I was asking in general, does this machine report the ID's correctly. More
> directed at Calvin, but part of it is the board vendor too. So I suspect no
> one can really answer "yes", despite that seeming to be the case.

I had tested RGMII PHYs(AR8035) with c22 using mdiobus_register. Vendor ID was
read out correctly while autoprobing.

AQR107(c45) PHYs that were connected gave back 0x00. This is expected
because the MDIO bus is configured to talk c22.

Regards
Calvin