When the port_window support was verified it was done on setup where only
the MEM_TO_DEV direction was enabled. This got un-noticed and thus only
this direction worked.

Now that I have managed to get a setup to verify both direction it turned
out that the setup was incorrect:
omap_desc members are settings for the slave port while the omap_sg members
apply to the memory side of the sDMA setup.

Fixes: 527a27591312 ("dmaengine: omap-dma: Fix the port_window support")
Signed-off-by: Peter Ujfalusi <peter.ujfal...@ti.com>
Cc: Russell King <li...@armlinux.org.uk>
Cc: dmaeng...@vger.kernel.org
Cc: dan.j.willi...@intel.com
Cc: vinod.k...@intel.com
---
 drivers/dma/omap-dma.c | 39 +++++++++++++++------------------------
 1 file changed, 15 insertions(+), 24 deletions(-)

diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index eed745a598fa..4fc86d40b50c 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -948,12 +948,6 @@ static struct dma_async_tx_descriptor 
*omap_dma_prep_slave_sg(
                return NULL;
        }
 
-       /* When the port_window is used, one frame must cover the window */
-       if (port_window) {
-               burst = port_window;
-               port_window_bytes = port_window * es_bytes[es];
-       }
-
        /* Now allocate and setup the descriptor. */
        d = kzalloc(sizeof(*d) + sglen * sizeof(d->sg[0]), GFP_ATOMIC);
        if (!d)
@@ -963,6 +957,21 @@ static struct dma_async_tx_descriptor 
*omap_dma_prep_slave_sg(
        d->dev_addr = dev_addr;
        d->es = es;
 
+       /* When the port_window is used, one frame must cover the window */
+       if (port_window) {
+               burst = port_window;
+               port_window_bytes = port_window * es_bytes[es];
+
+               d->ei = 1;
+               /*
+                * One frame covers the port_window and by  configure
+                * the source frame index to be -1 * (port_window - 1)
+                * we instruct the sDMA that after a frame is processed
+                * it should move back to the start of the window.
+                */
+               d->fi = -(port_window_bytes - 1);
+       }
+
        d->ccr = c->ccr | CCR_SYNC_FRAME;
        if (dir == DMA_DEV_TO_MEM) {
                d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
@@ -987,14 +996,6 @@ static struct dma_async_tx_descriptor 
*omap_dma_prep_slave_sg(
                d->ccr |= CCR_SRC_AMODE_POSTINC;
                if (port_window) {
                        d->ccr |= CCR_DST_AMODE_DBLIDX;
-                       d->ei = 1;
-                       /*
-                        * One frame covers the port_window and by  configure
-                        * the source frame index to be -1 * (port_window - 1)
-                        * we instruct the sDMA that after a frame is processed
-                        * it should move back to the start of the window.
-                        */
-                       d->fi = -(port_window_bytes - 1);
 
                        if (port_window_bytes >= 64)
                                d->csdp |= CSDP_DST_BURST_64;
@@ -1050,16 +1051,6 @@ static struct dma_async_tx_descriptor 
*omap_dma_prep_slave_sg(
                osg->addr = sg_dma_address(sgent);
                osg->en = en;
                osg->fn = sg_dma_len(sgent) / frame_bytes;
-               if (port_window && dir == DMA_DEV_TO_MEM) {
-                       osg->ei = 1;
-                       /*
-                        * One frame covers the port_window and by  configure
-                        * the source frame index to be -1 * (port_window - 1)
-                        * we instruct the sDMA that after a frame is processed
-                        * it should move back to the start of the window.
-                        */
-                       osg->fi = -(port_window_bytes - 1);
-               }
 
                if (d->using_ll) {
                        osg->t2_desc = dma_pool_alloc(od->desc_pool, GFP_ATOMIC,
-- 
2.12.2

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