On Tue, 31 Oct 2023 19:08:08 +1030
Subhajit Ghosh <subhajit.ghosh@xxxxxxxxxxxxxx> wrote:
> >
> >> +static struct iio_event_spec apds9306_event_spec_als[] = {
> >> + {
> >> + .type = IIO_EV_TYPE_THRESH,
> >> + .dir = IIO_EV_DIR_RISING,
> >> + .mask_shared_by_all = BIT(IIO_EV_INFO_VALUE),
> >> + }, {
> >> + .type = IIO_EV_TYPE_THRESH,
> >> + .dir = IIO_EV_DIR_FALLING,
> >> + .mask_shared_by_all = BIT(IIO_EV_INFO_VALUE),
> >> + }, {
> >> + .type = IIO_EV_TYPE_THRESH,
> >> + .mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),
> >> + }, {
> >> + .type = IIO_EV_TYPE_THRESH_ADAPTIVE,
> >> + .mask_shared_by_all = BIT(IIO_EV_INFO_VALUE) |
> >> + BIT(IIO_EV_INFO_ENABLE),
> >> + }, {
> >> + .type = IIO_EV_TYPE_THRESH,
> >> + .mask_separate = BIT(IIO_EV_INFO_ENABLE),
> > This matches an entry above for type. Don't have separate entries.
> >> + },
> >> +};
> >> +
> >> +static struct iio_event_spec apds9306_event_spec_clear[] = {
> >> + {
> >> + .type = IIO_EV_TYPE_THRESH,
> >> + .mask_separate = BIT(IIO_EV_INFO_ENABLE),
> >> + },
> >> +};
> >> +
> >> +#define APDS9306_CHANNEL(_type) \
> >> + .type = _type, \
> >> + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | \
> >> + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> >> + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) | \
> >> + BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> >
> > Scale on the intensity channel is interesting... What are the units?
> > There tend not to be any well defined units for intensity (as opposed
> > to illuminance). There may be gain on the signal, but it won't be in untils
> > that map directly to a scale userspace should apply. This is one of the
> > rare reasons for using the HARDWARE_GAIN element of the ABI.
> >
> > A tricky corner however as relationship between raw value and hardwaregain
> > is not tightly defined (as it can be really weird!)
> Hi Jonathan,
>
> Thank you for taking time for reviewing and clearing all my tiny doubts and
> queries especially for the dt and versioning part. Much appreciated.
>
> In the above case, should I not expose scale for the "clear" channel? Rather,
> how should I expose the "clear" channel to userspace?
What is the scale? What units to you get after applying it?
I suspect it's not well defined.
Not sure what we've done in similar cases in the past. Perhaps have
a look at those. There may be precedence for still using scale.
I'm about to jump on a long haul flight (delayed - sigh) so don't have
time to look myself!
Jonathan
>
> Regards,
> Subhajit Ghosh
>
> >
> >> +
> >> +static struct iio_chan_spec apds9306_channels_without_events[] = {
> >> + {
> >> + APDS9306_CHANNEL(IIO_LIGHT)
> >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> >> + }, {
> >> + APDS9306_CHANNEL(IIO_INTENSITY)
> >> + .channel2 = IIO_MOD_LIGHT_CLEAR,
> >> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> >> + .modified = 1,
> >> + },
> >> +};
> >
>
>
