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Date:   Thu, 19 Mar 2020 10:10:45 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     Florian Fainelli <f.fainelli@gmail.com>,
        Russell King - ARM Linux <linux@armlinux.org.uk>,
        David Miller <davem@davemloft.net>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next 1/3] net: phy: add and use phy_check_downshift
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On Wed, Mar 18, 2020 at 10:29:01PM +0100, Heiner Kallweit wrote:
> So far PHY drivers have to check whether a downshift occurred to be
> able to notify the user. To make life of drivers authors a little bit
> easier move the downshift notification to phylib. phy_check_downshift()
> compares the highest mutually advertised speed with the actual value
> of phydev->speed (typically read by the PHY driver from a
> vendor-specific register) to detect a downshift.
>  
> +/**
> + * phy_check_downshift - check whether downshift occurred
> + * @phydev: The phy_device struct
> + *
> + * Check whether a downshift to a lower speed occurred. If this should be the
> + * case warn the user.
> + */

Hi Heiner

Might be worth documenting here that phydev->speed needs to contain
the real speed, which typically requires a vendor-specific register.

    Andrew