[libcamera-devel] [PATCH v3 4/6] libcamera: camera_sensor: Break out properties initialization

[Kieran Bingham]

Hi Jacopo,

On 09/03/2020 18:04, Jacopo Mondi wrote:
> Refactor the CameraSensor properties initialization to a dedicated virtual
> function that derived classes could override to register sensor-specific
> properties values.

/properties/property/

> 
> While at it, move documentation of the properties() method to match the
> declaration order in the class definition and make the properties_ and
> subdev_ fields protected to allow subclasses access.
> 

Seems fine to me,

I fear how big initProperties() could get depending on what properties
we can obtain from V4L2 controls, but I don't think it's too much of a
worry - and we can factor as we grow.

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

> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  src/libcamera/camera_sensor.cpp       | 115 +++++++++++++++-----------
>  src/libcamera/include/camera_sensor.h |   7 +-
>  2 files changed, 73 insertions(+), 49 deletions(-)
> 
> diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
> index 8bfe02c9e8ff..354f4704299f 100644
> --- a/src/libcamera/camera_sensor.cpp
> +++ b/src/libcamera/camera_sensor.cpp
> @@ -51,7 +51,7 @@ LOG_DEFINE_CATEGORY(CameraSensor);
>   * Once constructed the instance must be initialized with init().
>   */
>  CameraSensor::CameraSensor(const MediaEntity *entity)
> -	: entity_(entity), properties_(properties::properties)
> +	: properties_(properties::properties), entity_(entity)
>  {
>  	subdev_ = new V4L2Subdevice(entity);
>  }
> @@ -93,45 +93,6 @@ int CameraSensor::init()
>  	if (ret < 0)
>  		return ret;
>  
> -	/* Retrieve and store the camera sensor properties. */
> -	const ControlInfoMap &controls = subdev_->controls();
> -	int32_t propertyValue;
> -
> -	/* Camera Location: default is front location. */
> -	const auto &locationControl = controls.find(V4L2_CID_CAMERA_SENSOR_LOCATION);
> -	if (locationControl != controls.end()) {
> -		int32_t v4l2Location =
> -			locationControl->second.def().get<int32_t>();
> -
> -		switch (v4l2Location) {
> -		default:
> -			LOG(CameraSensor, Warning)
> -				<< "Unsupported camera location "
> -				<< v4l2Location << ", setting to Front";
> -			/* Fall-through */
> -		case V4L2_LOCATION_FRONT:
> -			propertyValue = properties::CameraLocationFront;
> -			break;
> -		case V4L2_LOCATION_BACK:
> -			propertyValue = properties::CameraLocationBack;
> -			break;
> -		case V4L2_LOCATION_EXTERNAL:
> -			propertyValue = properties::CameraLocationExternal;
> -			break;
> -		}
> -	} else {
> -		propertyValue = properties::CameraLocationFront;
> -	}
> -	properties_.set(properties::Location, propertyValue);
> -
> -	/* Camera Rotation: default is 0 degrees. */
> -	const auto &rotationControl = controls.find(V4L2_CID_CAMERA_SENSOR_ROTATION);
> -	if (rotationControl != controls.end())
> -		propertyValue = rotationControl->second.def().get<int32_t>();
> -	else
> -		propertyValue = 0;
> -	properties_.set(properties::Rotation, propertyValue);
> -
>  	/* Enumerate and cache media bus codes and sizes. */
>  	const ImageFormats formats = subdev_->formats(0);
>  	if (formats.isEmpty()) {
> @@ -162,6 +123,58 @@ int CameraSensor::init()
>  	std::sort(mbusCodes_.begin(), mbusCodes_.end());
>  	std::sort(sizes_.begin(), sizes_.end());
>  
> +	return initProperties();
> +}
> +
> +/**
> + * \brief Initialize the camera sensor standard properties
> + *
> + * This method initializes the camera sensor standard properties, by inspecting
> + * the control information reported by the sensor subdevice.
> + *
> + * Derived classes may override this method to register sensor-specific
> + * properties if needed. If they do so, they shall call the base
> + * initProperties() method to register standard properties.
> + *
> + * \return 0 on success, a negative error code otherwise
> + */
> +int CameraSensor::initProperties()
> +{
> +	const ControlInfoMap &controlMap = subdev_->controls();
> +	int32_t propertyValue;
> +
> +	/* Camera Location: default is front location. */
> +	const auto &locationControl = controlMap.find(V4L2_CID_CAMERA_SENSOR_LOCATION);
> +	if (locationControl != controlMap.end()) {
> +		int32_t v4l2Location =
> +			locationControl->second.def().get<int32_t>();
> +		switch (v4l2Location) {
> +		case V4L2_LOCATION_EXTERNAL:
> +			propertyValue = properties::CameraLocationExternal;
> +			break;
> +		case V4L2_LOCATION_FRONT:
> +			propertyValue = properties::CameraLocationFront;
> +			break;
> +		case V4L2_LOCATION_BACK:
> +			propertyValue = properties::CameraLocationBack;
> +			break;
> +		default:
> +			LOG(CameraSensor, Error)
> +				<< "Unsupported camera location: " << v4l2Location;
> +			return -EINVAL;
> +		}
> +	} else {
> +		propertyValue = properties::CameraLocationFront;
> +	}
> +	properties_.set(properties::Location, propertyValue);
> +
> +	/* Camera Rotation: default is 0 degrees. */
> +	propertyValue = 0;
> +	const auto &rotationControl = controlMap.find(V4L2_CID_CAMERA_SENSOR_ROTATION);
> +	if (rotationControl != controlMap.end())
> +		propertyValue = rotationControl->second.def().get<int32_t>();
> +	properties_.set(properties::Rotation, propertyValue);
> +
>  	return 0;
>  }
>  
> @@ -327,12 +340,6 @@ int CameraSensor::getControls(ControlList *ctrls)
>  	return subdev_->getControls(ctrls);
>  }
>  
> -/**
> - * \fn CameraSensor::properties()
> - * \brief Retrieve the camera sensor properties
> - * \return The list of camera sensor properties
> - */
> -
>  /**
>   * \brief Write controls to the sensor
>   * \param[in] ctrls The list of controls to write
> @@ -363,11 +370,27 @@ int CameraSensor::setControls(ControlList *ctrls)
>  	return subdev_->setControls(ctrls);
>  }
>  
> +/**
> + * \fn CameraSensor::properties()
> + * \brief Retrieve the camera sensor properties
> + * \return The list of camera sensor properties
> + */
> +
>  std::string CameraSensor::logPrefix() const
>  {
>  	return "'" + subdev_->entity()->name() + "'";
>  }
>  
> +/**
> + * \var CameraSensor::properties_
> + * \brief The list of camera sensor properties
> + */
> +
> +/**
> + * \var CameraSensor::subdev_
> + * \brief The camera sensor V4L2 subdevice
> + */
> +
>  /**
>   * \class CameraSensorFactory
>   * \brief Factory of camera sensors
> diff --git a/src/libcamera/include/camera_sensor.h b/src/libcamera/include/camera_sensor.h
> index 633955591b36..747c37e8b2e4 100644
> --- a/src/libcamera/include/camera_sensor.h
> +++ b/src/libcamera/include/camera_sensor.h
> @@ -34,6 +34,7 @@ public:
>  	CameraSensor &operator=(const CameraSensor &) = delete;
>  
>  	int init();
> +	virtual int initProperties();
>  
>  	const MediaEntity *entity() const { return entity_; }
>  	const std::vector<unsigned int> &mbusCodes() const { return mbusCodes_; }
> @@ -53,14 +54,14 @@ public:
>  protected:
>  	std::string logPrefix() const;
>  
> +	ControlList properties_;
> +	V4L2Subdevice *subdev_;
> +
>  private:
>  	const MediaEntity *entity_;
> -	V4L2Subdevice *subdev_;
>  
>  	std::vector<unsigned int> mbusCodes_;
>  	std::vector<Size> sizes_;
> -
> -	ControlList properties_;
>  };
>  
>  class CameraSensorFactory
> 

-- 
Regards
--
Kieran