Message-ID: <f13b06e3-1947-b0f3-6523-d2986f085898@linaro.org>
Date:   Mon, 20 Mar 2023 11:20:32 +0100
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Subject: Re: [PATCH v2 1/7] dt-bindings: misc: Add the Lantiq PEF2466 E1/T1/J1
 framer
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To:     Herve Codina <herve.codina@bootlin.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Derek Kiernan <derek.kiernan@xilinx.com>,
        Dragan Cvetic <dragan.cvetic@xilinx.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, alsa-devel@alsa-project.org,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>
References: <20230316122741.577663-1-herve.codina@bootlin.com>
 <20230316122741.577663-2-herve.codina@bootlin.com>
 <96b01241-d57d-a460-4a8b-9e83eaab24ae@linaro.org>
 <20230320104619.468a304b@bootlin.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20230320104619.468a304b@bootlin.com>
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On 20/03/2023 10:46, Herve Codina wrote:
>>
>>> +
>>> +  lantiq,data-rate-bps:
>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>> +    enum: [2048000, 4096000, 8192000, 16384000]
>>> +    default: 2048000
>>> +    description:
>>> +      Data rate (bit per seconds) on the system highway.  
>>
>> Why do you need it? How is it different from clock? Do you expect some
>> DDR here?
> 
> This is needed to set the data position on the data line.
> If the data line clock (sysclk-rate-hz) is greater than 'data-rate-bps',
> the device interleaves some holes between data in the full frame.
> 
> The exact position of the data and the holes is defined by 'channel-phase'
> 
> So, two information are needed:
> - The number of slots available (deduced from 'lantiq,data-rate-bps')
> - The slot to use in the available slots ('lantiq,channel-phase" property
> 
> lantiq,data-rate-bps is not a clock but a property used to set the frame
> physical setting. ie the correct data position in the frame. 

OK

(...)

>>> +additionalProperties: false
>>> +
>>> +examples:
>>> +  - |
>>> +    #include <dt-bindings/gpio/gpio.h>
>>> +    pef2256@2000000 {  
>>
>> Figure out some generic node name.
> 
> What do you think about 'framer' ?

Sure, I don't have particular proposal.


Best regards,
Krzysztof