libcamera: controls: Add support for float controls

Add support for float values in Control<> and ControlValue classes.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

include/libcamera/controls.h

@@ -24,6 +24,7 @@ enum ControlType {
 	ControlTypeBool,
 	ControlTypeInteger32,
 	ControlTypeInteger64,
+	ControlTypeFloat,
 };
 
 namespace details {
@@ -52,6 +53,11 @@ struct control_type<int64_t> {
 	static constexpr ControlType value = ControlTypeInteger64;
 };
 
+template<>
+struct control_type<float> {
+	static constexpr ControlType value = ControlTypeFloat;
+};
+
 template<typename T, std::size_t N>
 struct control_type<Span<T, N>> : public control_type<std::remove_cv_t<T>> {
 };