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Date:   Sat, 12 Mar 2022 18:46:46 -0800
From:   Richard Cochran <richardcochran@gmail.com>
To:     Andrew Lunn <andrew@lunn.ch>
Cc:     Woojung.Huh@microchip.com, linux@armlinux.org.uk,
        Horatiu.Vultur@microchip.com, Divya.Koppera@microchip.com,
        netdev@vger.kernel.org, hkallweit1@gmail.com, davem@davemloft.net,
        kuba@kernel.org, robh+dt@kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, UNGLinuxDriver@microchip.com,
        Madhuri.Sripada@microchip.com, Manohar.Puri@microchip.com
Subject: Re: [PATCH net-next 2/3] dt-bindings: net: micrel: Configure latency
 values and timestamping check for LAN8814 phy
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On Sat, Mar 12, 2022 at 09:04:31PM +0100, Andrew Lunn wrote:
> Do these get passed to the kernel so the hardware can act on them, or
> are they used purely in userspace by ptp4l?

user space only.
 
> If they has passed to the kernel, could we provide a getter as well as
> a setter, so the defaults hard coded in the driver can be read back?

Any hard coded defaults in the kernel are a nuisance.

I mean, do you want user space to say,

   "okay, so I know the correct value is X.  But the drivers may offer
   random values according to kernel version.  So, I'll read out the
   driver value Y, and then apply X-Y."

Insanity.

(not to mention that this fails for older kernels without the proposed
interface)

Thanks,
Richard