Re: [PATCH net-next 0/5] net: ethernet: adi: adin1110: Add OPEN Alliance TC6 support

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Nov 04, 2026 at 08:06:56AM +0000, Stolniceanu, Iustin wrote:
> On Tue, Nov 03, 2026 at 20:49 UTC, Andrew Lunn wrote:
> > On Tue, Nov 03, 2026 at 06:09:13PM +0200, Iustin Stolniceanu wrote:
> > > The ADIN1110 supports two SPI host interface protocols: the generic SPI
> > > protocol, which the adin1110 driver implements today, and the OPEN
> > > Alliance TC6 protocol. The protocol is selected by the SPI_CFG1 pin,
> > > which the device latches when it comes out of reset.
> >
> > Is it possible to read the status of this pin from a register?
> 
> No, not for SPI_CFG1. The ADIN1110 has no register that reports the 
> SPI_CFG1 level or the selected host protocol.

Seems like a badly thought out hardware design.

> The only way to detect the mode at runtime would be to probe it:
> read the PHYID register using one framing and fall back to the
> other if the value does not match. I have not tried that yet, and I
> am not sure that clocking a transaction in the wrong framing is
> harmless for the device, so I went with a DT property describing how
> the board straps the pin.
> 
> If you would prefer autodetection, I can try it on hardware for V2.

Do you have an reference design using a jumper, so you can try all
combinations? At minimum, it would be good to probe the chip, print an
error message, and return ENODEV, if the property and the hardware
don't match.

      Andrew