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Date:   Wed, 10 Feb 2021 11:38:18 +0100
From:   Michael Walle <michael@walle.cc>
To:     Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc:     Heiner Kallweit <hkallweit1@gmail.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Andrew Lunn <andrew@lunn.ch>,
        "David S . Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>
Subject: Re: [PATCH net-next 7/9] net: phy: icplus: select page before writing
 control register
In-Reply-To: <20210210103059.GR1463@shell.armlinux.org.uk>
References: <20210209164051.18156-1-michael@walle.cc>
 <20210209164051.18156-8-michael@walle.cc>
 <d5672062-c619-02a4-3bbe-dad44371331d@gmail.com>
 <20210210103059.GR1463@shell.armlinux.org.uk>
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Am 2021-02-10 11:30, schrieb Russell King - ARM Linux admin:
> On Wed, Feb 10, 2021 at 08:03:07AM +0100, Heiner Kallweit wrote:
>> On 09.02.2021 17:40, Michael Walle wrote:
>> > +out:
>> > +	return phy_restore_page(phydev, oldpage, err);
>> 
>> If a random page was set before entering config_init, do we actually 
>> want
>> to restore it? Or wouldn't it be better to set the default page as 
>> part
>> of initialization?
> 
> I think you've missed asking one key question: does the paging on this
> PHY affect the standardised registers at 0..15 inclusive, or does it
> only affect registers 16..31?

For this PHY it affects only registers >=16. But that doesn't invaldiate
the point that for other PHYs this might affect all regsisters. Eg. ones
where you could select between fiber and copper pages, right?

> If it doesn't affect the standardised registers, then the genphy_*
> functions don't care which page is selected.

-- 
-michael