diff --git a/include/libcamera/bound_method.h b/include/libcamera/bound_method.h
index 38c44b923ba1..54c40fc52e3b 100644
--- a/include/libcamera/bound_method.h
+++ b/include/libcamera/bound_method.h
@@ -13,9 +13,6 @@
 namespace libcamera {
 
 class Object;
-template<typename... Args>
-class Signal;
-class SignalBase;
 
 class BoundMethodBase
 {
@@ -28,7 +25,7 @@ public:
 	bool match(T *obj) { return obj == obj_; }
 	bool match(Object *object) { return object == object_; }
 
-	void disconnect(SignalBase *signal);
+	Object *object() const { return object_; }
 
 	void activatePack(void *pack);
 	virtual void invokePack(void *pack) = 0;
@@ -93,6 +90,8 @@ public:
 	BoundMemberMethod(T *obj, Object *object, void (T::*func)(Args...))
 		: BoundMethodArgs<Args...>(obj, object), func_(func) {}
 
+	bool match(void (T::*func)(Args...)) const { return func == func_; }
+
 	void activate(Args... args)
 	{
 		if (this->object_)
@@ -107,7 +106,6 @@ public:
 	}
 
 private:
-	friend class Signal<Args...>;
 	void (T::*func_)(Args...);
 };
 
@@ -118,11 +116,12 @@ public:
 	BoundStaticMethod(void (*func)(Args...))
 		: BoundMethodArgs<Args...>(nullptr, nullptr), func_(func) {}
 
+	bool match(void (*func)(Args...)) const { return func == func_; }
+
 	void activate(Args... args) { (*func_)(args...); }
 	void invoke(Args... args) {}
 
 private:
-	friend class Signal<Args...>;
 	void (*func_)(Args...);
 };
 
diff --git a/include/libcamera/signal.h b/include/libcamera/signal.h
index 3b6de30f7d35..b8a60281cceb 100644
--- a/include/libcamera/signal.h
+++ b/include/libcamera/signal.h
@@ -46,7 +46,9 @@ public:
 	~Signal()
 	{
 		for (BoundMethodBase *slot : slots_) {
-			slot->disconnect(this);
+			Object *object = slot->object();
+			if (object)
+				object->disconnect(this);
 			delete slot;
 		}
 	}
@@ -95,11 +97,11 @@ public:
 			/*
 			 * If the object matches the slot, the slot is
 			 * guaranteed to be a member slot, so we can safely
-			 * cast it to BoundMemberMethod<T, Args...> and access its
-			 * func_ member.
+			 * cast it to BoundMemberMethod<T, Args...> to match
+			 * func.
 			 */
 			if (slot->match(obj) &&
-			    static_cast<BoundMemberMethod<T, Args...> *>(slot)->func_ == func) {
+			    static_cast<BoundMemberMethod<T, Args...> *>(slot)->match(func)) {
 				iter = slots_.erase(iter);
 				delete slot;
 			} else {
@@ -113,7 +115,7 @@ public:
 		for (auto iter = slots_.begin(); iter != slots_.end(); ) {
 			BoundMethodArgs<Args...> *slot = *iter;
 			if (slot->match(nullptr) &&
-			    static_cast<BoundStaticMethod<Args...> *>(slot)->func_ == func) {
+			    static_cast<BoundStaticMethod<Args...> *>(slot)->match(func)) {
 				iter = slots_.erase(iter);
 				delete slot;
 			} else {
diff --git a/src/libcamera/bound_method.cpp b/src/libcamera/bound_method.cpp
index 0a2d61a6c805..23b8f4122283 100644
--- a/src/libcamera/bound_method.cpp
+++ b/src/libcamera/bound_method.cpp
@@ -13,12 +13,6 @@
 
 namespace libcamera {
 
-void BoundMethodBase::disconnect(SignalBase *signal)
-{
-	if (object_)
-		object_->disconnect(signal);
-}
-
 void BoundMethodBase::activatePack(void *pack)
 {
 	if (Thread::current() == object_->thread()) {