Re: [PATCH 1/4] dt-bindings: iio: adc: ad7768-1: add new supported parts

From: Krzysztof Kozlowski
Date: Tue Aug 19 2025 - 02:39:57 EST


On 18/08/2025 23:04, Jonathan Santos wrote:
> On 08/16, Jonathan Cameron wrote:
>> On Thu, 14 Aug 2025 08:03:23 +0200
>> Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>>
>>> On 14/08/2025 00:39, Jonathan Santos wrote:
>>>>>>
>>>>>> + adi,aaf-gain:
>>>>>> + description: |
>>>>>> + Specifies the gain of the Analog Anti-Aliasing Filter (AAF) applied to the
>>>>>> + ADC input, measured in milli-units. The AAF provides additional signal
>>>>>
>>>>> What is milli unit? Isn't gain in dB, so maybe you want mB? Quite
>>>>> unpopular to see mB, but we cannot use 1/100 of dB, so I could
>>>>> understand it.
>>>>>
>>>>
>>>> Actually, the gain is expressed in V/V, not in dB. I may have phrased it poorly, but since
>>>> there are fractional values like 0.364 and 0.143, I chose to represent it
>>>> in milli-units.
>>>
>>> Why your reply to is corrupted:
>>> "c3cf9b97-3883-4ebb-a2ed-0033adebda87@xxxxxxxxxx"?
>>>
>>>
>>> What sort of unit is milli-unit? Isn't this 1/1000 of some BASE unit,
>>> but you do not have here a base?
>>>
>>> I think you want just basis point if this is V/V (already in common
>>> property suffixes)
>> Nice. I didn't know about -bp. That does sound like a good choice for ratio
>> stuff and here would be 100x larger actual values which is fine.
>>
>
> Yes, it would be, but the here it is 1000x larger than the
> actual value (1/1000 V/V). I don't see another unit in

Huh? How? 1000x larger would be = 1... This makes no sense...


> property-units.yaml for this specifc case. Maybe using -milli suffix
> like in 'adi,ad4000.yaml' and 'adi,ad7380.yaml'?


Best regards,
Krzysztof