dmaengine: at_xdmac: fix a bug in transfer residue computation

The total size of the transfer was wrong in at_xdmac_prep_slave_sg()
resulting in bad computation of the transfer residue by
at_xdmac_tx_status().

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index fa9d75adf4d7..bf2aacbbf4cc 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -562,6 +562,7 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
         struct scatterlist      *sg;
         int                     i;
         u32                     cfg;
+        unsigned int            xfer_size = 0;
 
         if (!sgl)
                 return NULL;
@@ -637,12 +638,13 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                 dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
                          __func__, desc, first);
                 list_add_tail(&desc->desc_node, &first->descs_list);
+                xfer_size += len;
         }
 
         spin_unlock_bh(&atchan->lock);
 
         first->tx_dma_desc.flags = flags;
-        first->xfer_size = sg_len;
+        first->xfer_size = xfer_size;
         first->direction = direction;
 
         return &first->tx_dma_desc;