Re: [PATCH v2 2/4] iio: core: Add IIO_EV_INFO_SCALE to event info

[David Lechner]

On 2/2/26 9:19 AM, Taha Ed-Dafili wrote:
> Hi David,
> 
> Thanks for the feedback. You're right—"missing" was poor wording; I’ll
> rephrase to "implement support in the core" for v3 to reflect that this
> is an infrastructure addition.
> 
> Regarding existing users, the current lack of IIO_EV_INFO_SCALE in the core
> forces developers into manual workarounds to stay ABI-compliant. For
> instance, in drivers/iio/accel/mma8452.c, the developer used
> IIO_CONST_ATTR_NAMED to create a manual in_accel_scale and linked it via
> .event_attrs. This approach is static and bypasses the standard event_spec
> infrastructure.

OK, so it looks like there is just one existing user of any events/*_scale
attribute then. That would explain why there isn't a IIO_EV_INFO_SCALE.
It just isn't very common.

> 
> My goal with adding IIO_EV_INFO_SCALE is to provide a standard path to
> report these scales dynamically through read_event_value(), ensuring ABI
> compliance without manual sysfs boilerplate.
> 
> Does this core infrastructure approach seem like the right architectural
> path, or would you prefer I stick to a driver-level attribute for the
> ADXL345? Regardless of the path chosen, I will address your other comments
> in the next version: I'll fix the "in scale" typo and add the new scale
> entries to the adxl345 documentation table.

If we think there will be more users of this and we want to make it more
discoverable, then adding IIO_EV_INFO_SCALE seems useful.

I would wait until Jonathan weighs in with his opinion before taking action
though.

> 
> Thanks,
> Taha