Re: [PATCH v2 2/2] iio: adc: Add rtq6056 support

Andy Shevchenko
2022-07-04T21:52:35Z

On Mon, Jul 4, 2022 at 9:27 AM ChiYuan Huang <u0084500@gmail.com> wrote:
> ChiYuan Huang <u0084500@gmail.com> 於 2022年7月4日 週一 上午11:16寫道：
> > Andy Shevchenko <andy.shevchenko@gmail.com> 於 2022年7月1日 週五 下午6:05寫道：
> > > On Wed, Jun 29, 2022 at 4:23 AM cy_huang <u0084500@gmail.com> wrote:

...

> > > > + *val = DIV_ROUND_UP(1000000, sample_time);
> > >
> > > USEC_PER_SEC ?
> > >
> > No, sample time is (vshunt convesion time + vbus conversion time) *
> > average sample.
> > And the sample freq returns the unit by HZ (sample frequency per second)
> >
> The 'sample time' is unit by micro-second like as you mentioned.

Ah, then it should be MICRO, so we will get Hz.

> > > > + return IIO_VAL_INT;
> > > > +}

...

> > > > + struct {
> > > > + u16 vals[RTQ6056_MAX_CHANNEL];
> > > > + int64_t timestamp;
> > > > + } data __aligned(8);
> > >
> > > Hmm... alignment of this struct will be at least 4 bytes, but
> > > shouldn't we rather be sure that the timestamp member is aligned
> > > properly? Otherwise this seems fragile and dependent on
> > > RTQ6056_MAX_CHANNEL % 4 == 0.
> > >
> > Yap, from the 'max channel', it already guarantee this struct will be
> > aligned at lease 4.
> > Actually, It can be removed.

I think for the safest side it should be given to the timestamp member. No?

--
With Best Regards,
Andy Shevchenko