Re: [PATCH v2 1/1] iio: accel: adxl367: fix setting odr for activity time update

[Lothar Rubusch]

Hi Jonathan,

On Mon, Mar 10, 2025 at 9:10 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> On Sun,  9 Mar 2025 19:35:15 +0000
> Lothar Rubusch <l.rubusch@xxxxxxxxx> wrote:
>
> > Fix setting the odr value to update activity time based on frequency
> > derrived by recent odr, and not by obsolete odr value.
> >
> > The [small] bug: When _adxl367_set_odr() is called with a new odr value,
> > it first writes the new odr value to the hardware register
> > ADXL367_REG_FILTER_CTL.
> > Second, it calls _adxl367_set_act_time_ms(), which calls
> > adxl367_time_ms_to_samples(). Here st->odr still holds the old odr value.
> > This st->odr member is used to derrive a frequency value, which is
> > applied to update ADXL367_REG_TIME_ACT. Hence, the idea is to update
> > activity time, based on possibilities and power consumption by the
> > current ODR rate.
> > Finally, when the function calls return, again in _adxl367_set_odr() the
> > new ODR is assigned to st->odr.
> >
> > The fix: When setting a new ODR value is set to ADXL367_REG_FILTER_CTL,
> > also ADXL367_REG_TIME_ACT should probably be updated with a frequency
> > based on the recent ODR value and not the old one. Changing the location
> > of the assignment to st->odr fixes this.
> >
> > Fixes: cbab791c5e2a5 ("iio: accel: add ADXL367 driver")
> > Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx>
> > Reviewed-by: Marcelo Schmitt <marcelo.schmitt1@xxxxxxxxx>
> > ---
> Change log missing, but I assume it's just the Fixes tag.
> If so, I would have been fine with that just being in a reply
> to the v1. Anyhow, new patch is fine too so applied to the
> fixes-togreg branch of iio.git.  I may well queue this up for
> the merge window rather than send another pull request this cycle.
>

Yes, it is actually just the fixes tag and reviewed-by tag. I'm sorry
for the missing log.

Best,
L

> Thanks
>
> Jonathan
>
>
> >  drivers/iio/accel/adxl367.c | 10 +++-------
> >  1 file changed, 3 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/iio/accel/adxl367.c b/drivers/iio/accel/adxl367.c
> > index add4053e7a02..0c04b2bb7efb 100644
> > --- a/drivers/iio/accel/adxl367.c
> > +++ b/drivers/iio/accel/adxl367.c
> > @@ -601,18 +601,14 @@ static int _adxl367_set_odr(struct adxl367_state *st, enum adxl367_odr odr)
> >       if (ret)
> >               return ret;
> >
> > +     st->odr = odr;
> > +
> >       /* Activity timers depend on ODR */
> >       ret = _adxl367_set_act_time_ms(st, st->act_time_ms);
> >       if (ret)
> >               return ret;
> >
> > -     ret = _adxl367_set_inact_time_ms(st, st->inact_time_ms);
> > -     if (ret)
> > -             return ret;
> > -
> > -     st->odr = odr;
> > -
> > -     return 0;
> > +     return _adxl367_set_inact_time_ms(st, st->inact_time_ms);
> >  }
> >
> >  static int adxl367_set_odr(struct iio_dev *indio_dev, enum adxl367_odr odr)
>