libcamera: ipa_interface: Add support for custom IPA data to configure()

Add two new parameters, ipaConfig and result, to the
IPAInterface::configure() function to allow pipeline handlers to pass
custom data to their IPA, and receive data back. Wire this through the
code base. The C API interface will be addressed separately, likely
through automation of the C <-> C++ translation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

src/libcamera/ipa_interface.cpp

@@ -557,6 +557,8 @@ namespace libcamera {
  * \param[in] sensorInfo Camera sensor information
  * \param[in] streamConfig Configuration of all active streams
  * \param[in] entityControls Controls provided by the pipeline entities
+ * \param[in] ipaConfig Pipeline-handler-specific configuration data
+ * \param[out] result Pipeline-handler-specific configuration result
  *
  * This method shall be called when the camera is started to inform the IPA of
  * the camera's streams and the sensor settings. The meaning of the numerical
@@ -566,6 +568,11 @@ namespace libcamera {
  * The \a sensorInfo conveys information about the camera sensor settings that
  * the pipeline handler has selected for the configuration. The IPA may use
  * that information to tune its algorithms.
+ *
+ * The \a ipaConfig and \a result parameters carry custom data passed by the
+ * pipeline handler to the IPA and back. The pipeline handler may set the \a
+ * result parameter to null if the IPA protocol doesn't need to pass a result
+ * back through the configure() function.
  */
 
 /**