Re: [PATCH] iio: light: vcnl4000: Fix scale for vcnl4040

[Guido Günther]

Hi,
On Fri, Dec 27, 2019 at 09:47:20AM +0100, Marco Felsch wrote:
> Hi Guido,
> 
> On 19-12-23 16:30, Guido Günther wrote:
> > According to the data sheet the ambient sensors's scale is 0.12
> > lux/step, not 0.024 lux/step as used by vcnl4200.
> 
> This is only true if the als_it bits are set to '0'. Is it worth to add
> a comment here?

Good point. I've added that to the commit message.
Cheers,
 -- Guido

> 
> > See p. 8 in https://www.vishay.com/docs/84307/designingvcnl4040.pdf
> > 
> > Fixes: 5a441aade5b3 ("light: vcnl4000 add support for the VCNL4040 proximity and light sensor")
> > Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
> 
> Reviewed-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> 
> > ---
> >  drivers/iio/light/vcnl4000.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
> > index 16dacea9eadf..b0e241aaefb4 100644
> > --- a/drivers/iio/light/vcnl4000.c
> > +++ b/drivers/iio/light/vcnl4000.c
> > @@ -163,7 +163,6 @@ static int vcnl4200_init(struct vcnl4000_data *data)
> >  	if (ret < 0)
> >  		return ret;
> >  
> > -	data->al_scale = 24000;
> >  	data->vcnl4200_al.reg = VCNL4200_AL_DATA;
> >  	data->vcnl4200_ps.reg = VCNL4200_PS_DATA;
> >  	switch (id) {
> > @@ -172,11 +171,13 @@ static int vcnl4200_init(struct vcnl4000_data *data)
> >  		/* show 54ms in total. */
> >  		data->vcnl4200_al.sampling_rate = ktime_set(0, 54000 * 1000);
> >  		data->vcnl4200_ps.sampling_rate = ktime_set(0, 4200 * 1000);
> > +		data->al_scale = 24000;
> >  		break;
> >  	case VCNL4040_PROD_ID:
> >  		/* Integration time is 80ms, add 10ms. */
> >  		data->vcnl4200_al.sampling_rate = ktime_set(0, 100000 * 1000);
> >  		data->vcnl4200_ps.sampling_rate = ktime_set(0, 100000 * 1000);
> > +		data->al_scale = 120000;
> >  		break;
> >  	}
> >  	data->vcnl4200_al.last_measurement = ktime_set(0, 0);
> > -- 
> > 2.23.0
>