Re: [PATCH v3 6/6] iio: adc: ad4851: add ad485x driver

From: David Lechner
Date: Tue Oct 15 2024 - 12:08:34 EST


On 10/15/24 6:11 AM, Andy Shevchenko wrote:
> On Mon, Oct 14, 2024 at 08:15:15PM +0100, Jonathan Cameron wrote:
>> On Mon, 14 Oct 2024 16:14:27 +0300
>> Andy Shevchenko <andy@xxxxxxxxxx> wrote:
>>> On Mon, Oct 14, 2024 at 12:40:40PM +0300, Antoniu Miclaus wrote:
>
> ...
>
>>>> +config AD4851
>>>> + tristate "Analog Device AD4851 DAS Driver"
>>>> + depends on SPI
>>>> + select REGMAP_SPI
>>>> + select IIO_BACKEND
>>>> + help
>>>> + Say yes here to build support for Analog Devices AD4851, AD4852,
>>>> + AD4853, AD4854, AD4855, AD4856, AD4857, AD4858, AD4858I high speed
>>>> + data acquisition system (DAS).
>>>
>>> I think I already commented on this... Anyway, it's much better to support when
>>> this list is broke down on per device per line. In such a case it's less churn
>>> if we need to remove or add an entry in the future.
>>>
>>>> + To compile this driver as a module, choose M here: the module will be
>>>> + called ad4851.
>>>
>>> Also, with all these devices to be supported why not ad485x as the name of
>>> the driver? Is it a preference by the IIO subsystem?
>>
>> Don't. We've been bitten by too many cases of manufacturers noticing
>> a hole in their part numbers and 'slotting' something unrelated in.
>> So it just causes confusion. Hence strong preference for any new code
>> is pick a name from the list. The wild card also implies restrictions
>> that tend to break overtime when other part numbers outside the range
>> are used. Not using a wildcard keeps it consistently wrong so people
>> get used to it :)
>
> I see your point!
>
> But shouldn't we have a formal criteria for choosing that one from the list?
> I would go with "most featured device" as it may be aligned with all enabled
> features that otherwise would be questionable / confusing for the chips that
> do not support them or support in a limited manner.
>

I always go with the lowest number supported by the driver at the time
the driver was created. It is a simple, objective criteria and no one
has to spend time looking through features to decide which one is "best".