[PATCH] ipa: rpi: Fix for incorrectly reported max shutter speed

[Naushir Patuck]

Hi Laurent,

On Sat, 4 May 2024 at 16:04, Laurent Pinchart
<laurent.pinchart at ideasonboard.com> wrote:
>
> Hi Naush,
>
> On Wed, May 01, 2024 at 05:04:03PM +0100, Naushir Patuck wrote:
> > On Wed, 1 May 2024 at 16:53, Laurent Pinchart wrote:
> > > On Fri, Apr 26, 2024 at 12:18:15PM +0100, Naushir Patuck wrote:
> > > > The maximum shutter speed calculation in the cam-helper relied on
> > > > the frame duration limits being correctly set in the cam-helper's mode
> > > > structure. This was not the case on first startup, so the maximum
> > > > shutter speed reported back via the ControlInfo was incorrect.
> > > >
> > > > Fix this by setting up the camera mode in the cam-helper before querying
> > > > for the max shutter value.
> > > >
> > > > Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
> > > > ---
> > > >  src/ipa/rpi/common/ipa_base.cpp | 6 ++++++
> > > >  1 file changed, 6 insertions(+)
> > > >
> > > > diff --git a/src/ipa/rpi/common/ipa_base.cpp b/src/ipa/rpi/common/ipa_base.cpp
> > > > index 149a133ab662..1d12262bda01 100644
> > > > --- a/src/ipa/rpi/common/ipa_base.cpp
> > > > +++ b/src/ipa/rpi/common/ipa_base.cpp
> > > > @@ -592,6 +592,12 @@ void IpaBase::setMode(const IPACameraSensorInfo &sensorInfo)
> > > >       mode_.minAnalogueGain = helper_->gain(gainCtrl.min().get<int32_t>());
> > > >       mode_.maxAnalogueGain = helper_->gain(gainCtrl.max().get<int32_t>());
> > > >
> > > > +     /*
> > > > +      * We need to give the helper the min/max frame durations so it can calculate
> > > > +      * the correct exposure limits below.
> > > > +      */
> > > > +     helper_->setCameraMode(mode_);
> > > > +
> > >
> > > Don't you end up doing this twice, once here, and once in
> > > IpaBase::configure(), which calls IpaBase::setMode() ?
> >
> > Yes, it does happen twice.  The other option would be to pass a const
> > reference to mode_ into the helper through setMode(), allowing us only do
> > it once.
>
> I don't think I follow you.

What I mean is that we don't give the cam helper its own copy of the
mode structure, but pass it a const reference to the IPA's mode
structure.   This would solve the problem with the calculation here.

Regards,
Naush

>
> > But that was a bit more involved over this more trivial fix.  I
> > can change to do that if folks prefer.
> >
> > > >       /* Shutter speed is calculated based on the limits of the frame durations. */
> > > >       mode_.minShutter = helper_->exposure(shutterCtrl.min().get<int32_t>(), mode_.minLineLength);
> > > >       mode_.maxShutter = Duration::max();
>
> --
> Regards,
>
> Laurent Pinchart