[libcamera-devel] [PATCH v7 2/3] libcamera: camera_sensor: Enable to set a test pattern mode

[Hirokazu Honda]

Hi Laurent,

On Wed, Nov 24, 2021 at 1:53 PM Laurent Pinchart
<laurent.pinchart at ideasonboard.com> wrote:
>
> Hi Hiro,
>
> Thank you for the patch.
>
> On Wed, Nov 24, 2021 at 04:08:11AM +0900, Hirokazu Honda wrote:
> > This adds a function to set a camera sensor driver a test pattern
> > mode.
> >
> > Signed-off-by: Hirokazu Honda <hiroh at chromium.org>
> > Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
>
> The patch I've reviewed differs significantly from this one. Please drop
> my tag in v8.
>
> > ---
> >  include/libcamera/internal/camera_sensor.h |  7 +++
> >  src/libcamera/camera_sensor.cpp            | 60 +++++++++++++++++++---
> >  src/libcamera/control_ids.yaml             |  5 ++
> >  3 files changed, 65 insertions(+), 7 deletions(-)
> >
> > diff --git a/include/libcamera/internal/camera_sensor.h b/include/libcamera/internal/camera_sensor.h
> > index edef2220..f355f323 100644
> > --- a/include/libcamera/internal/camera_sensor.h
> > +++ b/include/libcamera/internal/camera_sensor.h
> > @@ -27,6 +27,9 @@ namespace libcamera {
> >
> >  class BayerFormat;
> >  class MediaEntity;
> > +class Request;
>
> Not needed anymore.
>
> > +
> > +struct CameraSensorProperties;
> >
> >  class CameraSensor : protected Loggable
> >  {
> > @@ -47,6 +50,7 @@ public:
> >       {
> >               return testPatternModes_;
> >       }
> > +     int setTestPatternMode(controls::draft::TestPatternModeEnum testPatternMode);
> >
> >       V4L2SubdeviceFormat getFormat(const std::vector<unsigned int> &mbusCodes,
> >                                     const Size &size) const;
> > @@ -82,6 +86,8 @@ private:
> >       std::unique_ptr<V4L2Subdevice> subdev_;
> >       unsigned int pad_;
> >
> > +     const CameraSensorProperties *staticProps_;
> > +
> >       std::string model_;
> >       std::string id_;
> >
> > @@ -89,6 +95,7 @@ private:
> >       std::vector<unsigned int> mbusCodes_;
> >       std::vector<Size> sizes_;
> >       std::vector<controls::draft::TestPatternModeEnum> testPatternModes_;
> > +     controls::draft::TestPatternModeEnum testPatternMode_;
> >
> >       Size pixelArraySize_;
> >       Rectangle activeArea_;
> > diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
> > index f0aa9f24..e1293980 100644
> > --- a/src/libcamera/camera_sensor.cpp
> > +++ b/src/libcamera/camera_sensor.cpp
> > @@ -17,6 +17,7 @@
> >  #include <string.h>
> >
> >  #include <libcamera/property_ids.h>
> > +#include <libcamera/request.h>
>
> Not needed anymore either.
>
> >
> >  #include <libcamera/base/utils.h>
> >
> > @@ -54,8 +55,9 @@ LOG_DEFINE_CATEGORY(CameraSensor)
> >   * Once constructed the instance must be initialized with init().
> >   */
> >  CameraSensor::CameraSensor(const MediaEntity *entity)
> > -     : entity_(entity), pad_(UINT_MAX), bayerFormat_(nullptr),
> > -       properties_(properties::properties)
> > +     : entity_(entity), pad_(UINT_MAX), staticProps_(nullptr),
> > +       testPatternMode_(controls::draft::TestPatternModeUnset),
> > +       bayerFormat_(nullptr), properties_(properties::properties)
> >  {
> >  }
> >
> > @@ -300,14 +302,14 @@ void CameraSensor::initVimcDefaultProperties()
> >
> >  void CameraSensor::initStaticProperties()
> >  {
> > -     const CameraSensorProperties *props = CameraSensorProperties::get(model_);
> > -     if (!props)
> > +     staticProps_ = CameraSensorProperties::get(model_);
> > +     if (!staticProps_)
> >               return;
> >
> >       /* Register the properties retrieved from the sensor database. */
> > -     properties_.set(properties::UnitCellSize, props->unitCellSize);
> > +     properties_.set(properties::UnitCellSize, staticProps_->unitCellSize);
> >
> > -     initTestPatternModes(props->testPatternModes);
> > +     initTestPatternModes(staticProps_->testPatternModes);
> >  }
> >
> >  void CameraSensor::initTestPatternModes(
> > @@ -315,7 +317,15 @@ void CameraSensor::initTestPatternModes(
> >  {
> >       const auto &v4l2TestPattern = controls().find(V4L2_CID_TEST_PATTERN);
> >       if (v4l2TestPattern == controls().end()) {
> > -             LOG(CameraSensor, Debug) << "No static test pattern map for \'"
> > +             LOG(CameraSensor, Debug)
> > +                     << "V4L2_CID_TEST_PATTERN is not supported";
> > +             return;
> > +     }
> > +
> > +     if (testPatternModes.empty()) {
> > +             // The camera sensor supports test patterns but we don't know
> > +             // how to map them so this should be fixed.
>
> We use C-style comments.
>
> > +             LOG(CameraSensor, Error) << "No static test pattern map for \'"
>
> No need to escape the single quote.
>
> >                                        << model() << "\'";
> >               return;
> >       }
> > @@ -531,6 +541,42 @@ Size CameraSensor::resolution() const
> >   * \return The list of test pattern modes
> >   */
> >
> > +/**
> > + * \brief Set the test pattern mode for the camera sensor
> > + * \param[in] testPatternMode Test pattern mode control value to set the camera
> > + * sensor
> > + *
> > + * \return 0 on success or a negative error code otherwise
> > + */
> > +int CameraSensor::setTestPatternMode(controls::draft::TestPatternModeEnum testPatternMode)
> > +{
> > +     if (testPatternMode_ == testPatternMode)
> > +             return 0;
> > +
> > +     if (!staticProps_ || testPatternModes_.empty())
> > +             return 0;
>
> Shouldn't this return an error ?
>
> > +
> > +     auto it = std::find(testPatternModes_.begin(), testPatternModes_.end(),
> > +                         testPatternMode);
> > +     if (it == testPatternModes_.end()) {
> > +             LOG(CameraSensor, Error) << "Unsupported test pattern mode "
> > +                                      << testPatternMode;
> > +             return -EINVAL;
> > +     }
> > +
> > +     int32_t index = staticProps_->testPatternModes.at(testPatternMode);
> > +     ControlList ctrls{ controls() };
> > +     ctrls.set(V4L2_CID_TEST_PATTERN, index);
> > +
> > +     int ret = setControls(&ctrls);
> > +     if (ret)
> > +             return ret;
> > +
> > +     testPatternMode_ = testPatternMode;
>
> This brings the question of where control values should be cached, to
> avoid applying controls that haven't changed. I don't think this need is
> limited to the CameraSensor class, so a more generic solution at the
> pipeline handler level may be better. This doesn't have to be addressed
> now though.
>
> > +
> > +     return 0;
> > +}
> > +
> >  /**
> >   * \brief Retrieve the best sensor format for a desired output
> >   * \param[in] mbusCodes The list of acceptable media bus codes
> > diff --git a/src/libcamera/control_ids.yaml b/src/libcamera/control_ids.yaml
> > index 9d4638ae..083bac7b 100644
> > --- a/src/libcamera/control_ids.yaml
> > +++ b/src/libcamera/control_ids.yaml
> > @@ -639,6 +639,11 @@ controls:
> >          Control to select the test pattern mode. Currently identical to
> >          ANDROID_SENSOR_TEST_PATTERN_MODE.
> >        enum:
> > +        - name: TestPatternModeUnset
> > +          value: -1
> > +          description: |
> > +            No test pattern is set. Returned frames by the camera device are
> > +            undefined.
>
> Why do we need this ? It's not documented in the commit message. If we
> need this new value, its addition should be split to a separate commit,
> with a proper explanation.
>

It was suggested by Kieran.
I originally used -1 for the initialized value of a test pattern mode
in CameraSensor.
-1 lets the first setTestPatternMode(Off) be executed.
It seems hack as -1 is invalid test pattern mode. So Kieran would like
to introduce this value.

If we move the cache of testpatternmode to ipu3 pipeline handler, this
may is not necessary.

Regards,
-Hiro
> >          - name: TestPatternModeOff
> >            value: 0
> >            description: |
>
> --
> Regards,
>
> Laurent Pinchart