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Subject: Re: [PATCH V1 1/4] bindings: nvmem: introduce "reverse-data" property
To:     Joakim Zhang <qiangqing.zhang@nxp.com>, robh+dt@kernel.org,
        shawnguo@kernel.org
Cc:     kernel@pengutronix.de, linux-imx@nxp.com,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20210810073510.18218-1-qiangqing.zhang@nxp.com>
 <20210810073510.18218-2-qiangqing.zhang@nxp.com>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Message-ID: <6e3f6881-929d-1663-58f1-39bf35069175@linaro.org>
Date:   Wed, 11 Aug 2021 11:16:49 +0100
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On 10/08/2021 08:35, Joakim Zhang wrote:
> Introduce "reverse-data" property for nvmem provider to reverse buffer.
> 
> Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
> ---
>   Documentation/devicetree/bindings/nvmem/nvmem.yaml | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/nvmem/nvmem.yaml b/Documentation/devicetree/bindings/nvmem/nvmem.yaml
> index b8dc3d2b6e92..bc745083fc64 100644
> --- a/Documentation/devicetree/bindings/nvmem/nvmem.yaml
> +++ b/Documentation/devicetree/bindings/nvmem/nvmem.yaml
> @@ -61,6 +61,11 @@ patternProperties:
>                 description:
>                   Size in bit within the address range specified by reg.
>   
> +      reverse-data:
> +        $ref: /schemas/types.yaml#/definitions/flag
> +        description:
> +          Reverse the data that read from the storage device.
> +

This new property is only going to solve one of the reverse order issue 
here.
If I remember correctly we have mac-address stored in various formats 
ex: from old thread I can see

Type 1: Octets in ASCII without delimiters. (Swapped/non-Swapped)
Type 2: Octets in ASCII with delimiters like (":", ",", ".", "-"... so 
on) (Swapped/non-Swapped)
Type 3: Is the one which stores mac address in Type1/2 but this has to 
be incremented to be used on other instances of eth.
Type 4: Octets as bytes/u8, swapped/non-swapped

I think its right time to consider adding compatibles to nvmem-cells to 
be able to specify encoding information and handle post processing.


Lets see what Rob would say on this approach.


--srini

>       required:
>         - reg
>   
>