[COMMON] media: smfc: cancel queued buffers in .stop_streaming()

stop_streaming() waits for all queued buffers to be finished. But SMFC
driver as a mem2mem device, may wait for the queued buffer of the
current vb2_queue while no buffer is queued in the other vb2_queue.
If .stop_streaming() is called in that situation, it waits for a
buffer to be queued to the other vb2_queue infinitely.
However it will never happen because no user will queue a buffer
during stopping operations on the device. Therefore, the driver
should see if other vb2_queue has a queued buffer when this vb2_queue
is stopping streaming. If the other vb2_queue has no queued buffer,
stop_streaming() should cancel all queued buffers in the current
vb2_queue.

Change-Id: I3b07916707a0b0d238a3238621fea631df8b942d
Signed-off-by: Cho KyongHo <pullip.cho@samsung.com>

diff --git a/drivers/media/platform/exynos/smfc/smfc.c b/drivers/media/platform/exynos/smfc/smfc.c
index b19494f0231c966a8b8c9eceb56872ea4765a43e..70f43f772596bcbe12acdcc3770083d6b29aaf95 100644 (file)
--- a/drivers/media/platform/exynos/smfc/smfc.c
+++ b/drivers/media/platform/exynos/smfc/smfc.c
@@ -415,6 +415,18 @@ static void smfc_vb2_unlock(struct vb2_queue *vq)
 
 static void smfc_vb2_stop_streaming(struct vb2_queue *vq)
 {
+       struct smfc_ctx *ctx = vb2_get_drv_priv(vq);
+
+       if ((V4L2_TYPE_IS_OUTPUT(vq->type) &&
+                       !v4l2_m2m_num_dst_bufs_ready(ctx->m2mctx)) ||
+               (!V4L2_TYPE_IS_OUTPUT(vq->type) &&
+                       !v4l2_m2m_num_src_bufs_ready(ctx->m2mctx))) {
+               unsigned int i;
+               /* cancel all queued buffers */
+               for (i = 0; i < vq->num_buffers; ++i)
+                       vb2_buffer_done(vq->bufs[i], VB2_BUF_STATE_ERROR);
+       }
+
        vb2_wait_for_all_buffers(vq);
 }