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