[media] cx23885: ensure video is streaming before allowing vbi to stream

Signed-off-by: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/media/video/cx23885/cx23885-video.c b/drivers/media/video/cx23885/cx23885-video.c
index a182e829c8d0..44a63c4de122 100644
--- a/drivers/media/video/cx23885/cx23885-video.c
+++ b/drivers/media/video/cx23885/cx23885-video.c
@@ -1100,6 +1100,14 @@ static int vidioc_streamon(struct file *file, void *priv,
 
         if (unlikely(!res_get(dev, fh, get_resource(fh))))
                 return -EBUSY;
+
+        /* Don't start VBI streaming unless vida streaming
+         * has already started.
+         */
+        if ((fh->type == V4L2_BUF_TYPE_VBI_CAPTURE) &&
+                ((cx_read(VID_A_DMA_CTL) & 0x11) == 0))
+                return -EINVAL;
+
         return videobuf_streamon(get_queue(fh));
 }