dmaengine: tegra-apb: Remove duplicated residue calculation

The calculation of the DMA residue for the Tegra APB DMA is duplicated
in two places in the tegra_dma_tx_status() function. Remove this
duplicated code by moving calculation to the end of the function and
only calculating if we found a valid descriptor.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index bc91fea..a8de08b 100644 (file)
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -819,13 +819,8 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
        /* Check on wait_ack desc status */
        list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
                if (dma_desc->txd.cookie == cookie) {
-                       residual =  dma_desc->bytes_requested -
-                                       (dma_desc->bytes_transferred %
-                                               dma_desc->bytes_requested);
-                       dma_set_residue(txstate, residual);
                        ret = dma_desc->dma_status;
-                       spin_unlock_irqrestore(&tdc->lock, flags);
-                       return ret;
+                       goto found;
                }
        }
 
@@ -833,17 +828,22 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
        list_for_each_entry(sg_req, &tdc->pending_sg_req, node) {
                dma_desc = sg_req->dma_desc;
                if (dma_desc->txd.cookie == cookie) {
-                       residual =  dma_desc->bytes_requested -
-                                       (dma_desc->bytes_transferred %
-                                               dma_desc->bytes_requested);
-                       dma_set_residue(txstate, residual);
                        ret = dma_desc->dma_status;
-                       spin_unlock_irqrestore(&tdc->lock, flags);
-                       return ret;
+                       goto found;
                }
        }
 
        dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie);
+       dma_desc = NULL;
+
+found:
+       if (dma_desc) {
+               residual = dma_desc->bytes_requested -
+                          (dma_desc->bytes_transferred %
+                           dma_desc->bytes_requested);
+               dma_set_residue(txstate, residual);
+       }
+
        spin_unlock_irqrestore(&tdc->lock, flags);
        return ret;
 }