[media] vb2: Move buffer cache synchronisation to prepare from queue

The buffer cache should be synchronised in buffer preparation, not when
the buffer is queued to the device. Fix this.

Mmap buffers do not need cache synchronisation since they are always
coherent.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index 9f3ce3b669c142ae98b92dc6cbc94456adf980a6..3107e2196e54e7272c4346b6f3dcc65f05ecbbc7 100644 (file)
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -1227,23 +1227,19 @@ err:
 static void __enqueue_in_driver(struct vb2_buffer *vb)
 {
        struct vb2_queue *q = vb->vb2_queue;
-       unsigned int plane;
 
        vb->state = VB2_BUF_STATE_ACTIVE;
        atomic_inc(&q->owned_by_drv_count);
 
        trace_vb2_buf_queue(q, vb);
 
-       /* sync buffers */
-       for (plane = 0; plane < vb->num_planes; ++plane)
-               call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
-
        call_void_vb_qop(vb, buf_queue, vb);
 }
 
 static int __buf_prepare(struct vb2_buffer *vb, const void *pb)
 {
        struct vb2_queue *q = vb->vb2_queue;
+       unsigned int plane;
        int ret;
 
        if (q->error) {
@@ -1268,11 +1264,19 @@ static int __buf_prepare(struct vb2_buffer *vb, const void *pb)
                ret = -EINVAL;
        }
 
-       if (ret)
+       if (ret) {
                dprintk(1, "buffer preparation failed: %d\n", ret);
-       vb->state = ret ? VB2_BUF_STATE_DEQUEUED : VB2_BUF_STATE_PREPARED;
+               vb->state = VB2_BUF_STATE_DEQUEUED;
+               return ret;
+       }
 
-       return ret;
+       /* sync buffers */
+       for (plane = 0; plane < vb->num_planes; ++plane)
+               call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
+
+       vb->state = VB2_BUF_STATE_PREPARED;
+
+       return 0;
 }
 
 int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb)