sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev);
if (IS_ERR(sur40->alloc_ctx)) {
dev_err(sur40->dev, "Can't allocate buffer context");
sur40->alloc_ctx = vb2_dma_sg_init_ctx(sur40->dev);
if (IS_ERR(sur40->alloc_ctx)) {
dev_err(sur40->dev, "Can't allocate buffer context");