[media] V4L: mx3_camera: implement .stop_streaming()

The .stop_streaming() videobuf2 operation has to be implemented to
guarantee, that video buffers are not written to after a STREAMOFF.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/mx3_camera.c

@@ -400,6 +400,35 @@ static int mx3_videobuf_init(struct vb2_buffer *vb)
 	return 0;
 }
 
+static int mx3_stop_streaming(struct vb2_queue *q)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(q);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct mx3_camera_dev *mx3_cam = ici->priv;
+	struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
+	struct dma_chan *chan;
+	struct mx3_camera_buffer *buf, *tmp;
+	unsigned long flags;
+
+	if (ichan) {
+		chan = &ichan->dma_chan;
+		chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
+	}
+
+	spin_lock_irqsave(&mx3_cam->lock, flags);
+
+	mx3_cam->active = NULL;
+
+	list_for_each_entry_safe(buf, tmp, &mx3_cam->capture, queue) {
+		buf->state = CSI_BUF_NEEDS_INIT;
+		list_del_init(&buf->queue);
+	}
+
+	spin_unlock_irqrestore(&mx3_cam->lock, flags);
+
+	return 0;
+}
+
 static struct vb2_ops mx3_videobuf_ops = {
 	.queue_setup	= mx3_videobuf_setup,
 	.buf_prepare	= mx3_videobuf_prepare,
@@ -408,6 +437,7 @@ static struct vb2_ops mx3_videobuf_ops = {
 	.buf_init	= mx3_videobuf_init,
 	.wait_prepare	= soc_camera_unlock,
 	.wait_finish	= soc_camera_lock,
+	.stop_streaming	= mx3_stop_streaming,
 };
 
 static int mx3_camera_init_videobuf(struct vb2_queue *q,