[libcamera-devel] [PATCH 2/2] libipa: Correct IMX219 in CameraSensorHelper

[Laurent Pinchart]

On Fri, Nov 19, 2021 at 11:14:34AM +0000, Kieran Bingham wrote:
> Quoting Jean-Michel Hautbois (2021-11-19 10:25:59)
> > The equation is badly reported in the CameraSensorHelper, as m1 and c0
> > are inverted. Correct it to have a proper gain calculation.
> > 
> 
> I feel like this would be easier to spot if this was all constructed
> from a single table. But perhaps that's not as extensible in the future,
> which is why we've got the individual constructors.

Agreed, there's a bit of room for improvements in the syntax.

> Anyway, this update matches more closely to the IMX258 now, so it looks
> better from that comparative perspective at least...
> 
> I can't really add more value than that and I don't know what to check
> specifically on the datasheets so

Registers 0x008c to 0x0093: m0 = 0x0000, c0 = 0x0100, m1 = 0xffff,
c1 = 0x0100.

> Acked-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
> > ---
> >  src/ipa/libipa/camera_sensor_helper.cpp | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/src/ipa/libipa/camera_sensor_helper.cpp b/src/ipa/libipa/camera_sensor_helper.cpp
> > index 67cf6913..5e22f9c3 100644
> > --- a/src/ipa/libipa/camera_sensor_helper.cpp
> > +++ b/src/ipa/libipa/camera_sensor_helper.cpp
> > @@ -292,7 +292,7 @@ class CameraSensorHelperImx219 : public CameraSensorHelper
> >  public:
> >         CameraSensorHelperImx219()
> >         {
> > -               analogueGainConstants_ = { AnalogueGainLinear, 0, -1, 256, 256 };
> > +               analogueGainConstants_ = { AnalogueGainLinear, 0, 256, -1, 256 };
> >         }
> >  };
> >  REGISTER_CAMERA_SENSOR_HELPER("imx219", CameraSensorHelperImx219)

-- 
Regards,

Laurent Pinchart