dmaengine: virt-dma: Add helper to free/reuse a descriptor

The vchan_vdesc_fini() can be used to free or reuse a given descriptor
after it has been marked as completed.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index 3f776a46a29c..2edb05505102 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -104,6 +104,20 @@ static inline void vchan_cookie_complete(struct virt_dma_desc *vd)
 }
 
 /**
+ * vchan_vdesc_fini - Free or reuse a descriptor
+ * @vd: virtual descriptor to free/reuse
+ */
+static inline void vchan_vdesc_fini(struct virt_dma_desc *vd)
+{
+        struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
+
+        if (dmaengine_desc_test_reuse(&vd->tx))
+                list_add(&vd->node, &vc->desc_allocated);
+        else
+                vc->desc_free(vd);
+}
+
+/**
  * vchan_cyclic_callback - report the completion of a period
  * @vd: virtual descriptor
  */