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Subject: Re: [net] net: usb: smsc95xx: fix external PHY reset
To:     Alexandru Tachici <alexandru.tachici@analog.com>,
        linux-kernel@vger.kernel.org
Cc:     andrew@lunn.ch, linux@armlinux.org.uk, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        netdev@vger.kernel.org, steve.glendinning@shawell.net,
        UNGLinuxDriver@microchip.com, andre.edich@microchip.com,
        linux-usb@vger.kernel.org
References: <20221114131643.19450-1-alexandru.tachici@analog.com>
From:   Sergei Shtylyov <sergei.shtylyov@gmail.com>
Message-ID: <adb2dc3c-fd1e-53ea-ca64-5c1600058890@gmail.com>
Date:   Mon, 14 Nov 2022 14:43:22 +0300
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Hello!

On 11/14/22 4:16 PM, Alexandru Tachici wrote:

> An external PHY needs settling time after power up or reser.

   Reset? :-)

> In the bind() function an mdio bus is registered. If at this point
> the external PHY is still initialising, no valid PHY ID will be
> read and on phy_find_first() the bind() function will fail.
> 
> If an external PHY is present, wait the maximum time specified
> in 802.3 45.2.7.1.1.
> 
> Fixes: 05b35e7eb9a1 ("smsc95xx: add phylib support")
> Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>

[...]

MBR, Sergey