qcam: viewfinder: Move multi-planar check into viewfinder

The lack of support for multiplanar buffers comes from the viewfinder.
Move the corresponding check from MainWindow.

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

src/qcam/main_window.cpp

@@ -524,14 +524,9 @@ void MainWindow::processCapture()
 	queueRequest(buffer);
 }
 
-int MainWindow::display(FrameBuffer *buffer)
+void MainWindow::display(FrameBuffer *buffer)
 {
-	if (buffer->planes().size() != 1)
-		return -EINVAL;
-
 	viewfinder_->display(buffer, &mappedBuffers_[buffer]);
-
-	return 0;
 }
 
 void MainWindow::queueRequest(FrameBuffer *buffer)

src/qcam/main_window.h

@@ -66,7 +66,7 @@ private:
 
 	void requestComplete(Request *request);
 	void processCapture();
-	int display(FrameBuffer *buffer);
+	void display(FrameBuffer *buffer);
 	void queueRequest(FrameBuffer *buffer);
 
 	/* UI elements */

src/qcam/viewfinder.cpp

@@ -11,6 +11,7 @@
 #include <QImageWriter>
 #include <QMutexLocker>
 #include <QPainter>
+#include <QtDebug>
 
 #include "format_converter.h"
 
@@ -27,6 +28,11 @@ ViewFinder::~ViewFinder()
 void ViewFinder::display(const libcamera::FrameBuffer *buffer,
 			 MappedBuffer *map)
 {
+	if (buffer->planes().size() != 1) {
+		qWarning() << "Multi-planar buffers are not supported";
+		return;
+	}
+
 	QMutexLocker locker(&mutex_);
 
 	/*