Re: [PATCH net-next v3 8/9] net: dsa: dsa_slave_phy_connect(): extend phy's flags with port specific phy flags

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: Woojung Huh <woojung.huh@microchip.com>,
	UNGLinuxDriver@microchip.com, Andrew Lunn <andrew@lunn.ch>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Vivien Didelot <vivien.didelot@gmail.com>,
	Vladimir Oltean <olteanv@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	kernel@pengutronix.de, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Michael Grzeschik <m.grzeschik@pengutronix.de>
Subject: Re: [PATCH net-next v3 8/9] net: dsa: dsa_slave_phy_connect(): extend phy's flags with port specific phy flags
Date: Wed, 26 May 2021 16:08:11 +0100	[thread overview]
Message-ID: <20210526150811.GF30436@shell.armlinux.org.uk> (raw)
In-Reply-To: <20210526043037.9830-9-o.rempel@pengutronix.de>

On Wed, May 26, 2021 at 06:30:36AM +0200, Oleksij Rempel wrote:
> This patch extends the flags of the phy that's being connected with the
> port specific flags of the switch port.
> 
> This is needed to handle a port specific erratum of the KSZ8873 switch,
> which is added in a later patch.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
>  drivers/net/phy/phylink.c | 2 +-
>  net/dsa/slave.c           | 4 ++++
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
> index 96d8e88b4e46..167c2277814f 100644
> --- a/drivers/net/phy/phylink.c
> +++ b/drivers/net/phy/phylink.c
> @@ -1029,7 +1029,7 @@ static int phylink_attach_phy(struct phylink *pl, struct phy_device *phy,
>  	if (pl->phydev)
>  		return -EBUSY;
>  
> -	return phy_attach_direct(pl->netdev, phy, 0, interface);
> +	return phy_attach_direct(pl->netdev, phy, phy->dev_flags, interface);

I don't think this has any benefit. phy_attach_direct() does this
internally:

        phydev->dev_flags |= flags;

which means the above change is effectively doing:

        phydev->dev_flags |= phydev->dev_flags;

So, are you sure you need this?

-- 
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