Re: [PATCH net-next 4/5] net: ethernet: adi: Add a driver for the ADIN1140 MACPHY
From: Andrew Lunn
Date: Sun May 03 2026 - 11:16:25 EST
On Sun, May 03, 2026 at 05:36:13AM +0200, Andrew Lunn wrote:
> On Sun, May 03, 2026 at 02:24:53AM +0300, Ciprian Regus via B4 Relay wrote:
> > From: Ciprian Regus <ciprian.regus@xxxxxxxxxx>
> >
> > Add a driver for ADIN1140. The device is a 10BASE-T1S MAC-PHY
> > (integrated in the same package) that connects to a CPU over an SPI bus,
> > and implements the Open Alliance TC6 protocol for control and frame
> > transfers. As such, this driver relies on oa_tc6 for the communication
> > with the device. The device has an alternative name (AD3306), so the
> > driver can be probed using one of the two compatible strings.
> >
> > For control transactions, ADIN1140 only implements the protected mode.
> > The driver has a custom implementation for the mii_bus access methods as a
> > workaround for hardware issues:
> >
> > 1. The OA TC6 standard defines the direct and indirect access modes for
> > MDIO transactions. The ADIN1140 incorrectly advertises indirect mode
> > only (supported capabilities register - 0x2, bit 9), while actually
> > implementing just the direct mode. We cannot rely on the CAP register
> > to choose an access method (which oa_tc6 does by default, even though
> > it only implements the direct mode), so the driver has to use its
> > own.
> > 2. The ADIN1140 cannot access the C22 register space of the internal
> > PHY, while the PHY is busy receiving frames. If that happens, the
> > CONFIG0 and CONFIG2 registers of the MAC will get corrupted and the
> > data transfer will stop. Those two registers configure settings for
> > the transfer protocol between the MAC and host, so the value for some
> > of their subfields shouldn't be changed while the netdev is up.
This device is pretty broken. Has it been shipped to customers? Is
there going to be a new stepping of the silicon which is less broken?
A new device to replace this one?
Andrew