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, 8 insertions, 4 deletions

diff --git a/src/libcamera/include/v4l2_controls.h b/src/libcamera/include/v4l2_controls.h
index b39370b2..71ce377f 100644
--- a/src/libcamera/include/v4l2_controls.h
+++ b/src/libcamera/include/v4l2_controls.h
@@ -20,23 +20,27 @@
 
 namespace libcamera {
 
+class V4L2ControlId : public ControlId
+{
+public:
+	V4L2ControlId(const struct v4l2_query_ext_ctrl &ctrl);
+};
+
 class V4L2ControlInfo
 {
 public:
 	V4L2ControlInfo(const struct v4l2_query_ext_ctrl &ctrl);
 
-	unsigned int id() const { return id_; }
+	const ControlId &id() const { return id_; }
 	unsigned int type() const { return type_; }
 	size_t size() const { return size_; }
-	const std::string &name() const { return name_; }
 
 	const ControlRange &range() const { return range_; }
 
 private:
-	unsigned int id_;
+	V4L2ControlId id_;
 	unsigned int type_;
 	size_t size_;
-	std::string name_;
 
 	ControlRange range_;
 };