Re: [PATCH 1/2] arm64: dts: renesas: r9a07g044: Fix external clk node names

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 25/04/2022 17:28, Biju Das wrote:
>>>> My suggestion was to move the [12] part into the first part, so the
>>>> suffix "clk" stays consistent:
>>>> audio1-clk
>>>> audio2-clk
>>>
>>> From HW perspective,  there are 2 audio clocks, audio clock1(multiple
>>> and sub multiple of 44.1 Khz) and audio clk 2(Multiple and submultiple
>> of 48Khz) connected to a single audio Codec.
>>>
>>> Based on the sampling rate, through clock generator driver we can
>>> switch the clock source for audio mclock along with audio clock for
>>> SSI and we can support both these rates
>>>
>>> Since there is a single audio codec, I am not sure, audio1-clk and
>> audio2-clk is a good choise.
>>
>> The name of the clock is not "audio clock" but "audio", because you do not
>> call a car "Ford Mustang car", but just "Ford Mustang". Therefore "clock"
>> is not part of the name, but just description of a type.
> 
> The hardware mention the name as AUDIO_CLK1 and AUDIO_CLK2.

The hardware document might call it "AUDIO_CLK_REAL_CLK_CLK" and it
won't be an argument to call device node that way in DTS.

> There are 2 Clock availables for audio interface.
> In that case if you term it as audio1-clk and audio-clk2,
> But as you said clk-1-audio and clk-2-audio will be correct?

If you change all other clocks to follow same principle - generic name
followed by specific suffix - then yes. Then you should have
"clk-extal", "clk-can" etc.

> 
>>
>>>
>>> What about like
>>>
>>> audio_clk1: audio-clk-1 ?
>>> audio_clk2: audio-clk-2 ?
>>>
>>> Which is consistent with naming used for cpu and opp-tables?
>>
>>
>> It's not consistent with clk naming. Nodes should have generic names, so
>> the generic part is "clk". You add specific audio/audio-X prefix or suffix
>> - it's fine, but not both.
>>
>> This is exactly the trouble when you start using specific names and
>> Devicetree spec explicitly asks for generic names. So maybe go with the
>> spec and call of these "clk-[0-9]" and problem is gone.
> 
> Ok Will change like
> 
> "audio_clk1: clk-1-audio"
> 

What do you mean "ok"? I said "clk-[0-9]", so "clk-0", "clk-1", "clk-2"
and so on. No specific prefix.

> Label name matches with hardware manual and node names as per Device tree spec.


Best regards,
Krzysztof