On Sat, Nov 12, 2016 at 04:36:37PM +0000, Jonathan Cameron wrote:
> On 10/11/16 09:25, Brian Masney wrote:
> > If channel 0 does not have any data, then the code sets the lux to zero.
> > The corresponding comment says that the last value is returned. This
> > updates the comment to correctly reflect what the code does.
> >
> > Signed-off-by: Brian Masney <masneyb@xxxxxxxxxxxxx>
> Better perhaps to just return an error, -EAGAIN perhaps?
> I'm not sure why it would not give a value.
This check is to avoid a division by zero. Here is the relevant code
that wasn't shown in the diff:
if (!ch0) {
/* have no data, so return 0 */
ret = 0;
chip->als_cur_info.lux = 0;
goto done;
}
/* calculate ratio */
ratio = (ch1 << 15) / ch0;
Channel 0 is sensitive to both infrared and visible light. In total
darkness, the sensor should return 0. Correct me if I am wrong, but
I believe that returning 0 here is more correct than -EAGAIN.
Brian
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