Re: [PATCH v3 1/2] dt-bindings: net: motorcomm: Add pad driver strength cfg

From: Guo Samin <samin.guo@starfivetech.com>
To: Conor Dooley <conor@kernel.org>
Cc: <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
	<netdev@vger.kernel.org>, Peter Geis <pgwipeout@gmail.com>,
	Frank <Frank.Sae@motor-comm.com>,
	"David S . Miller" <davem@davemloft.net>,
	"Eric Dumazet" <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Andrew Lunn <andrew@lunn.ch>,
	"Heiner Kallweit" <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Yanhong Wang <yanhong.wang@starfivetech.com>
Subject: Re: [PATCH v3 1/2] dt-bindings: net: motorcomm: Add pad driver strength cfg
Date: Mon, 29 May 2023 11:46:19 +0800	[thread overview]
Message-ID: <1dbf113c-7592-68bd-6aaf-05ff1d8c538c@starfivetech.com> (raw)
In-Reply-To: <20230526-glutinous-pristine-fed571235b80@spud>

Re: [PATCH v3 1/2] dt-bindings: net: motorcomm: Add pad driver strength cfg
From: Conor Dooley <conor@kernel.org>
to: Samin Guo <samin.guo@starfivetech.com>
data: 2023/5/27

> On Fri, May 26, 2023 at 05:05:01PM +0800, Samin Guo wrote:
>> The motorcomm phy (YT8531) supports the ability to adjust the drive
>> strength of the rx_clk/rx_data, the value range of pad driver
>> strength is 0 to 7.
>>
>> Signed-off-by: Samin Guo <samin.guo@starfivetech.com>
>> ---
>>  .../devicetree/bindings/net/motorcomm,yt8xxx.yaml    | 12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/net/motorcomm,yt8xxx.yaml b/Documentation/devicetree/bindings/net/motorcomm,yt8xxx.yaml
>> index 157e3bbcaf6f..29a1997a1577 100644
>> --- a/Documentation/devicetree/bindings/net/motorcomm,yt8xxx.yaml
>> +++ b/Documentation/devicetree/bindings/net/motorcomm,yt8xxx.yaml
>> @@ -52,6 +52,18 @@ properties:
>>        for a timer.
>>      type: boolean
>>  
>> +  motorcomm,rx-clk-driver-strength:
>> +    description: drive strength of rx_clk pad.
>> +    $ref: /schemas/types.yaml#/definitions/uint32
>> +    enum: [ 0, 1, 2, 3, 4, 5, 6, 7 ]
> 
> I think you should use minimum & maximum instead of these listed out
> enums.

Thanks Conor, This can be improved in the next version.

 You have also had this comment since v1 & were reminded of it on
> v2 by Krzysztof: "What do the numbers mean? What are the units? mA?"
> 

The good news is that we just got some data about units from Motorcomm. 
Maybe I can post the data show of the unit later after I get the complete data.

> This information should go into the binding, not sit in a thread on a
> mailing list that noone will look at when trying to write a DT :(
> 
> Thanks,
> Conor.
>

Yes，when we have the complete 'unit' data, it will be placed in DT.

Best regards,
Samin

>> +    default: 3
>> +
>> +  motorcomm,rx-data-driver-strength:
>> +    description: drive strength of rx_data/rx_ctl rgmii pad.
>> +    $ref: /schemas/types.yaml#/definitions/uint32
>> +    enum: [ 0, 1, 2, 3, 4, 5, 6, 7 ]
>> +    default: 3
>> +
>>    motorcomm,tx-clk-adj-enabled:
>>      description: |
>>        This configuration is mainly to adapt to VF2 with JH7110 SoC.
>> -- 
>> 2.17.1
>>