[media] pwc: do not decompress the image unless the state is DONE

There is no point in trying to decompress a captured frame unless
the buffer state is OK. It won't be used in any other state, and
in fact the contents of the buffer might well be corrupt.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

1 files changed, 9 insertions, 6 deletions

diff --git a/drivers/media/usb/pwc/pwc-if.c b/drivers/media/usb/pwc/pwc-if.c
index 1a27096b3f91..84a6720b1d00 100644
--- a/drivers/media/usb/pwc/pwc-if.c
+++ b/drivers/media/usb/pwc/pwc-if.c
@@ -619,12 +619,15 @@ static void buffer_finish(struct vb2_buffer *vb)
         struct pwc_device *pdev = vb2_get_drv_priv(vb->vb2_queue);
         struct pwc_frame_buf *buf = container_of(vb, struct pwc_frame_buf, vb);
 
-        /*
-         * Application has called dqbuf and is getting back a buffer we've
-         * filled, take the pwc data we've stored in buf->data and decompress
-         * it into a usable format, storing the result in the vb2_buffer
-         */
-        pwc_decompress(pdev, buf);
+        if (vb->state == VB2_BUF_STATE_DONE) {
+                /*
+                 * Application has called dqbuf and is getting back a buffer
+                 * we've filled, take the pwc data we've stored in buf->data
+                 * and decompress it into a usable format, storing the result
+                 * in the vb2_buffer.
+                 */
+                pwc_decompress(pdev, buf);
+        }
 }
 
 static void buffer_cleanup(struct vb2_buffer *vb)