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Subject: Re: [PATCH net-next v3 2/4] dt-bindings: net: Add Rx/Tx output
 configuration for 10base T1L
To:     Andrew Lunn <andrew@lunn.ch>
CC:     <davem@davemloft.net>, <f.fainelli@gmail.com>,
        <hkallweit1@gmail.com>, <robh@kernel.org>,
        <devicetree@vger.kernel.org>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20201030172950.12767-1-dmurphy@ti.com>
 <20201030172950.12767-3-dmurphy@ti.com> <20201030195655.GD1042051@lunn.ch>
From:   Dan Murphy <dmurphy@ti.com>
Message-ID: <a50fe8f3-2ca1-8969-08ac-013704a5a617@ti.com>
Date:   Tue, 3 Nov 2020 10:52:58 -0600
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Andrew

On 10/30/20 2:56 PM, Andrew Lunn wrote:
> On Fri, Oct 30, 2020 at 12:29:48PM -0500, Dan Murphy wrote:
>> Per the 802.3cg spec the 10base T1L can operate at 2 different
>> differential voltages 1v p2p and 2.4v p2p. The abiility of the PHY to
>> drive that output is dependent on the PHY's on board power supply.
> Hi Dan
>
> So this property is about the board being able to support the needed
> voltages? The PHY is not forced into 2.4v p2p, it just says the PHY
> can operate at 2.4v and the board will not melt, blow a fuse, etc?
>
> I actually think it is normal to specify the reverse. List the maximum
> that device can do because of board restrictions. e.g.
>
> - maximum-power-milliwatt : Maximum module power consumption
>    Specifies the maximum power consumption allowable by a module in the
>    slot, in milli-Watts.  Presently, modules can be up to 1W, 1.5W or 2W.
>
> - max-link-speed:
>     If present this property specifies PCI gen for link capability.  Host
>     drivers could add this as a strategy to avoid unnecessary operation for
>     unsupported link speed, for instance, trying to do training for
>     unsupported link speed, etc.  Must be '4' for gen4, '3' for gen3, '2'
>     for gen2, and '1' for gen1. Any other values are invalid.
>
>   - max-microvolt : The maximum voltage value supplied to the haptic motor.
>                  [The unit of the voltage is a micro]
>
> So i think this property should be
>
>     max-tx-rx-p2p = <1000>;

When I was re-writing the code I couldn't come up with a better property 
name but I like this one.

I will implement it.

Do you have any issue with the property being in the ethernet-phy.yaml?

Dan