Re: [bmp280 v1 3/6] iio: pressure: bmp280: implement sampling_frequency for BMx280

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 04 Aug 2025 19:29:48 +0200
ASSI <Stromeko@nexgo.de> wrote:

> Andy Shevchenko writes:
> >> +       .sampling_freq_default = BMP280_ODR_0HZ, /* MODE_FORCED */  
> >
> > Why is this comment repeated all over the code? Any justification why
> > it's so important, please?  
> 
> It's just a reminder that this value isn't actually used by the driver
> to do what it says in the datasheet, but instead for effecting the
> switching between MODE_FORCED and MODE_NORMAL.  If you'd really want to
> run the sensor with no standby between measurements there'd need to be
> an extra invalid value (like -1), that then would need to be guarded
> everywhere against getting used as an array index.
Call it BMP280_ODR_MODE_FORCED rather than making it 0HZ related?
Using the value 0 for the sysfs interface doesn't make much sense though.

Even if it is a pain to work out, we should estimate what it means to
use force mode wrt to how fast a single sample can be obtain.
It may be that is such that we don't bother with the other slow sampling
frequency modes if they are slower as they aren't useful vs only reading
when we want to.

Jonathan

> 
> 
> Regards,
> Achim.