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Subject: Re: [RFC PATCH] net: phy/mdio: enable mmd indirect access through
 phy_mii_ioctl()
To:     "Russell King (Oracle)" <linux@armlinux.org.uk>
CC:     Andrew Lunn <andrew@lunn.ch>,
        "David S. Miller" <davem@davemloft.net>, <netdev@vger.kernel.org>,
        Jakub Kicinski <kuba@kernel.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        <linux-kernel@vger.kernel.org>,
        Vignesh Raghavendra <vigneshr@ti.com>
References: <20211101182859.24073-1-grygorii.strashko@ti.com>
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From:   Grygorii Strashko <grygorii.strashko@ti.com>
Message-ID: <e18f17bd-9e77-d3ef-cc1e-30adccb7cdd5@ti.com>
Date:   Tue, 2 Nov 2021 20:37:08 +0200
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Hi Russell, Andrew,

Thanks a lot for you comments.

On 02/11/2021 19:41, Russell King (Oracle) wrote:
> On Tue, Nov 02, 2021 at 07:19:46PM +0200, Grygorii Strashko wrote:
>> It would require MDIO bus lock, which is not a solution,
>> or some sort of batch processing, like for mmd:
>>   w reg1 val1
>>   w reg2 val2
>>   w reg1 val3
>>   r reg2
>>
>> What Kernel interface do you have in mind?
> 
> That is roughly what I was thinking, but Andrew has basically said no
> to it.
> 
>> Sry, but I have to note that demand for this become terribly high, min two pings in months
> 
> Feel free to continue demanding it, but it seems that at least two of
> the phylib maintainers are in agreement that providing generic
> emulation of C45 accesses in kernel space is just not going to happen.
> 

not ready to give up.

One more idea how about mdiobus_get_phy(), so we can search for PHY and
if present try to use proper API phy_read/phy_write_mmd?


-- 
Best regards,
grygorii