Message-ID: <6247adab-2004-5159-69ca-9e1dd30f4c38@kernel.org>
Date:   Mon, 6 Mar 2023 17:09:00 +0100
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Subject: Re: [PATCH v1 1/2] dt-bindings: iio: adc: adding dt-bindings for
 PAC193X
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To:     Marius.Cristea@microchip.com, jic23@kernel.org
Cc:     devicetree@vger.kernel.org, lars@metafoo.de,
        linux-iio@vger.kernel.org, robh+dt@kernel.org,
        linux-kernel@vger.kernel.org
References: <20230220123232.413029-1-marius.cristea@microchip.com>
 <20230220123232.413029-2-marius.cristea@microchip.com>
 <c38afa67-d24f-0390-f18a-81bee15b7eca@kernel.org>
 <20230225171723.15e822ec@jic23-huawei>
 <2f1a14522a7a8d46e3b037a285af4c3dd9b17cbc.camel@microchip.com>
From:   Krzysztof Kozlowski <krzk@kernel.org>
In-Reply-To: <2f1a14522a7a8d46e3b037a285af4c3dd9b17cbc.camel@microchip.com>
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On 06/03/2023 14:53, Marius.Cristea@microchip.com wrote:
> 
> Hi Jonathan,
> 
>    Thank you so much! I'm happy to contribute to IIO.
> 
> I will remove some section because I agree with the propose solution.
> For the rest I will comment below..
> 
> 
> 
> On Sat, 2023-02-25 at 17:17 +0000, Jonathan Cameron wrote:
>>>> +
>>>> +  microchip,samp-rate:
>>>> +    $ref: /schemas/types.yaml#/definitions/uint32
>>>> +    description: Sampling rate for all device's channels.
>>>
>>> What are the units? rate is usually in hz, which should be
>>> expressed in
>>> unit suffix (property name)]
>>
>> It's unusual for sampling rate to be a property of the hardware and
>> hence
>> suitable for DT binding. Normally we make this a userspace control
>> instead.
>> If there is a reason for doing it from DT, that wants to be mentioned
>> here.
>>
> 
> Here I could change it into the datarate (as in
> iio/adc/ti,ads1015.yaml). The units are samples per second. My
> intention was to be alingned with the datasheet.
> 
> My intention was to let the user configure the sample rate as soon as
> posile during the startup (the PAC device's own power consumtion will
> increase with the sampling rate - default the chip will start with the
> maximum samples per second).

Then maybe the default should be just lowest rate and user will adjust
it further? Since this is user-space knob, why this should be even
configurable per board?


Best regards,
Krzysztof