[libcamera-devel] [PATCH v2] ipa: ipu3: Consolidate querying of exposure and gain limits

[Kieran Bingham]

Quoting Umang Jain (2022-03-03 12:15:44)
> Hi Kieran,
> 
> On 3/3/22 17:17, Kieran Bingham wrote:
> > Quoting Umang Jain (2022-03-01 07:59:19)
> >> The exposure and gain limits are required for AGC configuration
> >> handled in IPAIPU3::updateSessionConfiguration(), which is happening
> >> already. Therefore the max/min private members in IPAIPU3 class for
> >> exposure/gain serve no use except setting initial values of exposure_
> >> and gain_ members.
> >>
> >> Drop the max/min private members from IPAIPU3 class and set initial
> >> gain_ and exposure_ in  IPAIPU3::updateSessionConfiguration().
> >
> > Great, even better to drop them if they aren't used.
> >
> > This looks like we're on the path to removing the private variables for
> > controls from the IPAIPU3 now, as they should all be stored in the
> > context if there's any relationship with the algorithms.
> 
> 
> yeah, we are on that path.
> 
> >
> > Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> >
> >> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
> >> ---
> >> Changes in v2:
> >>   - Split into separate patch
> >>   - Prepped over "v4 ipa: ipu3: Misc clean up"
> >>   - Don't include max/min exposure/gain members in
> >>     IPASessionConfiguration, as they aren't used anywhere.
> >> ---
> >>   src/ipa/ipu3/ipu3.cpp | 26 ++------------------------
> >>   1 file changed, 2 insertions(+), 24 deletions(-)
> >>
> >> diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp
> >> index 17324616..4b6852a7 100644
> >> --- a/src/ipa/ipu3/ipu3.cpp
> >> +++ b/src/ipa/ipu3/ipu3.cpp
> >> @@ -167,11 +167,7 @@ private:
> >>          /* Camera sensor controls. */
> >>          uint32_t defVBlank_;
> >>          uint32_t exposure_;
> >> -       uint32_t minExposure_;
> >> -       uint32_t maxExposure_;
> >>          uint32_t gain_;
> >> -       uint32_t minGain_;
> >> -       uint32_t maxGain_;
> > What's required to get rid of gain_, exposure_ and defVBlank_ from here
> > too?
> 
> 
> we can drop gain_, exposure_ and replace them with local vars, no issue 
> in that.
> 
> defVBlank_ seems to be used IPAIPU3 class functions directly, but i 
> think we can move the defVBlank_ to JM's introduction of 
> IPASessionConfiguration.sensor structure
> 
> With this plan i think we can drop these remaining private members from 
> IPAIPU3.

Great, can easily be patches on top - doesn't need to be in this one.

--
Kieran


> 
> >
> > --
> > Kieran
> >
> >
> >>   
> >>          /* Interface to the Camera Helper */
> >>          std::unique_ptr<CameraSensorHelper> camHelper_;
> >> @@ -192,10 +188,12 @@ void IPAIPU3::updateSessionConfiguration(const ControlInfoMap &sensorControls)
> >>          const ControlInfo &v4l2Exposure = sensorControls.find(V4L2_CID_EXPOSURE)->second;
> >>          int32_t minExposure = v4l2Exposure.min().get<int32_t>();
> >>          int32_t maxExposure = v4l2Exposure.max().get<int32_t>();
> >> +       exposure_ = minExposure;
> >>   
> >>          const ControlInfo &v4l2Gain = sensorControls.find(V4L2_CID_ANALOGUE_GAIN)->second;
> >>          int32_t minGain = v4l2Gain.min().get<int32_t>();
> >>          int32_t maxGain = v4l2Gain.max().get<int32_t>();
> >> +       gain_ = minGain;
> >>   
> >>          /*
> >>           * When the AGC computes the new exposure values for a frame, it needs
> >> @@ -429,32 +427,12 @@ int IPAIPU3::configure(const IPAConfigInfo &configInfo,
> >>           */
> >>          ctrls_ = configInfo.sensorControls;
> >>   
> >> -       const auto itExp = ctrls_.find(V4L2_CID_EXPOSURE);
> >> -       if (itExp == ctrls_.end()) {
> >> -               LOG(IPAIPU3, Error) << "Can't find exposure control";
> >> -               return -EINVAL;
> >> -       }
> >> -
> >> -       const auto itGain = ctrls_.find(V4L2_CID_ANALOGUE_GAIN);
> >> -       if (itGain == ctrls_.end()) {
> >> -               LOG(IPAIPU3, Error) << "Can't find gain control";
> >> -               return -EINVAL;
> >> -       }
> >> -
> >>          const auto itVBlank = ctrls_.find(V4L2_CID_VBLANK);
> >>          if (itVBlank == ctrls_.end()) {
> >>                  LOG(IPAIPU3, Error) << "Can't find VBLANK control";
> >>                  return -EINVAL;
> >>          }
> >>   
> >> -       minExposure_ = itExp->second.min().get<int32_t>();
> >> -       maxExposure_ = itExp->second.max().get<int32_t>();
> >> -       exposure_ = minExposure_;
> >> -
> >> -       minGain_ = itGain->second.min().get<int32_t>();
> >> -       maxGain_ = itGain->second.max().get<int32_t>();
> >> -       gain_ = minGain_;
> >> -
> >>          defVBlank_ = itVBlank->second.def().get<int32_t>();
> >>   
> >>          calculateBdsGrid(configInfo.bdsOutputSize);
> >> -- 
> >> 2.31.1
> >>