libcamera: ipu3: Do not re-queue cancelled buffers

When a video device is stopped all the buffers there queued are released
and their state is set to BufferCancelled.

Currently, on buffer completion, cancelled buffers are blindly re-queued
to the ImgU input or CIO2 output devices, preventing them to be
re-started succesfully in future capture sessions.

Fix that by inspecting the buffers status and skip re-queueing if
they're reported as cancelled. For the ImgU output buffer this is not
required, as cancelled request should be reported to applications in
order to report them failure of the capture operations.

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

src/libcamera/pipeline/ipu3/ipu3.cpp

@@ -927,6 +927,10 @@ int PipelineHandlerIPU3::registerCameras()
  */
 void IPU3CameraData::imguInputBufferReady(Buffer *buffer)
 {
+	/* \todo Handle buffer failures when state is set to BufferError. */
+	if (buffer->status() == Buffer::BufferCancelled)
+		return;
+
 	cio2_.output_->queueBuffer(buffer);
 }
 
@@ -957,6 +961,10 @@ void IPU3CameraData::imguOutputBufferReady(Buffer *buffer)
  */
 void IPU3CameraData::cio2BufferReady(Buffer *buffer)
 {
+	/* \todo Handle buffer failures when state is set to BufferError. */
+	if (buffer->status() == Buffer::BufferCancelled)
+		return;
+
 	imgu_->input_->queueBuffer(buffer);
 }