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Message-ID: <5f09543db3de88e83116c5b2f6e3d9edbfdb4af8.camel@ew.tq-group.com>
Subject: Re: [PATCH net] net: dsa: mv88e6xx: fix supported_interfaces setup
 in mv88e6250_phylink_get_caps()
From: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
To: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Andrew Lunn <andrew@lunn.ch>, Florian Fainelli <f.fainelli@gmail.com>, 
 Vladimir Oltean <olteanv@gmail.com>, "David S. Miller"
 <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>,  Jakub Kicinski
 <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
  linux-kernel@vger.kernel.org, linux@ew.tq-group.com
Date: Wed, 17 Apr 2024 09:13:53 +0200
In-Reply-To: <Zh6trxU0hB+yt6rV@shell.armlinux.org.uk>
References: <20240416155054.3650354-1-matthias.schiffer@ew.tq-group.com>
	 <Zh6trxU0hB+yt6rV@shell.armlinux.org.uk>
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On Tue, 2024-04-16 at 17:56 +0100, Russell King (Oracle) wrote:
> On Tue, Apr 16, 2024 at 05:50:54PM +0200, Matthias Schiffer wrote:
> > +int mv88e6250_port_get_mode(struct mv88e6xxx_chip *chip, int port,
> > +			    phy_interface_t *mode)
> > +{
> > +	int err;
> > +	u16 reg;
> > +
> > +	if (port < 5) {
> > +		*mode =3D PHY_INTERFACE_MODE_INTERNAL;
> > +		return 0;
> > +	}
>=20
> Note that if mv88e6xxx_phy_is_internal() returns TRUE for the port,
> then this will be handled automatically.
>=20
> > +
> > +	err =3D mv88e6xxx_port_read(chip, port, MV88E6XXX_PORT_STS, &reg);
> > +	if (err)
> > +		return err;
> > +
> > +	switch (reg & MV88E6250_PORT_STS_PORTMODE_MASK) {
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_10_HALF_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_100_HALF_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_10_FULL_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_100_FULL_PHY:
> > +		*mode =3D PHY_INTERFACE_MODE_REVMII;
> > +		break;
> > +
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_HALF:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_FULL:
> > +		*mode =3D PHY_INTERFACE_MODE_MII;
> > +		break;
> > +
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_DUAL_100_RMII_FULL_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_200_RMII_FULL_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_10_100_RMII_HALF_PHY:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_10_100_RMII_FULL_PHY:
> > +		*mode =3D PHY_INTERFACE_MODE_REVRMII;
> > +		break;
> > +
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_DUAL_100_RMII_FULL:
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_10_100_RMII_FULL:
> > +		*mode =3D PHY_INTERFACE_MODE_RMII;
> > +		break;
> > +
> > +	case MV88E6250_PORT_STS_PORTMODE_MII_100_RGMII:
> > +		*mode =3D PHY_INTERFACE_MODE_RGMII;
> > +		break;
> > +
> > +	default:
> > +		*mode =3D PHY_INTERFACE_MODE_NA;
>=20
> What does this mean? I don't allow PHY_INTERFACE_MODE_NA to be set in
> the list of supported interfaces because it isn't an interface mode.
> If it's invalid, then it's probably best to return an error.
>=20
> I wonder whether it would just be better to pass the
> supported_interfaces bitmap into this function and have it set the
> appropriate bit itself, renaming the function to something more
> better suited to that purpose.
>=20
> Thanks.

I'm explicitly checking for PHY_INTERFACE_MODE_NA in the caller to handle t=
he "this interface isn't
useable" case. Passing supported_interfaces into the function handling the =
port modes is fine with
me, too - will send a v2 later.

Best regards,
Matthias


>=20

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