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Message-ID: <ebc34b27-31b2-b57a-ec0c-fb4e0fa25c1e@ti.com>
Date:   Tue, 11 Jul 2023 13:32:56 +0530
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Subject: Re: [PATCH] dt-bindings: ti-serdes-mux: Add defines for SERDES4 in
 J784S4 SoC
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To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        <peda@axentia.se>, <robh+dt@kernel.org>,
        <krzysztof.kozlowski+dt@linaro.org>, <conor+dt@kernel.org>
CC:     <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <s-vadapalli@ti.com>
References: <20230710102712.155195-1-j-choudhary@ti.com>
 <d136d58d-9582-3833-861f-086b64c1ad36@linaro.org>
 <ecbb6d34-e024-f6c6-5921-ba7bc6fe2e5e@ti.com>
 <97436a92-2cbd-0498-8aad-444ac3fab99b@linaro.org>
 <d54b0cc2-91d9-b081-fc39-0bbba715ee5b@ti.com>
 <80a43533-f6d6-b498-b677-08f7e608155a@linaro.org>
From:   Jayesh Choudhary <j-choudhary@ti.com>
In-Reply-To: <80a43533-f6d6-b498-b677-08f7e608155a@linaro.org>
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On 11/07/23 13:05, Krzysztof Kozlowski wrote:
> On 11/07/2023 09:21, Jayesh Choudhary wrote:
>>
>>
>> On 11/07/23 11:34, Krzysztof Kozlowski wrote:
>>> On 11/07/2023 07:55, Jayesh Choudhary wrote:
>>>> Hello Krzysztof,
>>>>
>>>> On 10/07/23 17:11, Krzysztof Kozlowski wrote:
>>>>> On 10/07/2023 12:27, Jayesh Choudhary wrote:
>>>>>> SERDES4 has 4 lanes. Add lane definitions for it.
>>>>>>
>>>>>> Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
>>>>>> ---
>>>>>>     include/dt-bindings/mux/ti-serdes.h | 20 ++++++++++++++++++++
>>>>>
>>>>> Where are the users of this binding constants? IOW, why do you need to
>>>>> add these?
>>>>>
>>>>> I don't see users of existing constants either...
>>>>>
>>>>
>>>> These constants are propagated in the idle-state property for the
>>>> mux-controller node (named serdes_ln_ctrl) usually in the final
>>>> board dts files and occasionally in the main dtsi files for TI SoCs.
>>>
>>> So they are not used.
>>
>> 'They' as in SERDES4 definition or others as well??
> 
> I made quick greps and it seems that none of the defines - existing and
> new - are used. But here anyway we talk about this patch, which without
> users does not have any rationale.
These defines are yet to be added. For reference:
https://lore.kernel.org/all/20230522092201.127598-3-s-vadapalli@ti.com/

SERDES4 by default is used for display but it can be configured for 
QSGMII too. There are users for that configuration as well. So it felt 
reasonable to add the definitions for SERDES4 which were missed earlier.

Warm Regards,
-Jayesh