Re: [RFC PATCH] net: phy/mdio: enable mmd indirect access through phy_mii_ioctl()

From: Grygorii Strashko <grygorii.strashko@ti.com>
To: Andrew Lunn <andrew@lunn.ch>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>,
	"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>
Subject: Re: [RFC PATCH] net: phy/mdio: enable mmd indirect access through phy_mii_ioctl()
Date: Wed, 3 Nov 2021 20:42:07 +0200	[thread overview]
Message-ID: <01a0ebf9-5d3f-e886-4072-acb9bf418b12@ti.com> (raw)
In-Reply-To: <YYHXcyCOPiUkk8Tz@lunn.ch>

On 03/11/2021 02:27, Andrew Lunn wrote:
>>> What i find interesting is that you and the other resent requester are
>>> using the same user space tool. If you implement C45 over C22 in that
>>> tool, you get your solution, and it will work for older kernels as
>>> well. Also, given the diverse implementations of this IOTCL, it
>>> probably works for more drivers than just those using phy_mii_ioctl().
>>
>> Do you mean change uapi, like
>>   add mdio_phy_id_is_c45_over_c22() and
>>   flag #define MDIO_PHY_ID_C45_OVER_C22 0x4000?
> 
> No, i mean user space implements C45 over C22. Make phytool write
> MII_MMD_CTRL and MII_MMD_DATA to perform a C45 over C22.

Now I give up - as mentioned there is now way to sync User space vs Kernel
MMD transactions and so no way to get trusted results.

Thanks all for participating in discussion.

-- 
Best regards,
grygorii