libcamera: v4l2_controls: Add V4L2ControlId

Add a V4L2 specialisation of the ControlId class, in order to construct
a ControlId from a v4l2_query_ext_ctrl. The V4L2ControlId is embedded in
V4L2ControlInfo, and thus needs to be copyable to allow for
V4L2ControlInfo to be passed to IPAs. The ControlId copy constructor and
assignment operators are thus restored, but made protected to avoid the
Control class being copyable.

This is needed in order to use ControlList for V4L2 controls, as
ControlList requires ControlId instances for all controls.

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

1 files changed, 4 insertions, 3 deletions

diff --git a/include/libcamera/controls.h b/include/libcamera/controls.h
index 5e6708fe..ebc4204f 100644
--- a/include/libcamera/controls.h
+++ b/include/libcamera/controls.h
@@ -68,11 +68,12 @@ protected:
 		: id_(id), name_(name), type_(type)
 	{
 	}
+#ifndef __DOXYGEN__
+	ControlId &operator=(const ControlId &) = default;
+	ControlId(const ControlId &) = default;
+#endif
 
 private:
-	ControlId(const ControlId &) = delete;
-	ControlId &operator=(const ControlId &) = delete;
-
 	unsigned int id_;
 	std::string name_;
 	ControlType type_;