From e598e6eb46dd448d9b77a564e4d9664da52e3e1f Mon Sep 17 00:00:00 2001 From: Kedareswara rao Appana Date: Sat, 9 Jul 2016 14:09:48 +0530 Subject: [PATCH] dmaengine: xilinx: Fix race condition in axi dma cyclic dma mode In cyclic DMA mode need to link the tail bd segment with the head bd segment to process bd's in cyclic. Current driver is doing this only for tx channel needs to update the same for rx channel case also. This patch fixes the same. Signed-off-by: Kedareswara rao Appana Signed-off-by: Vinod Koul --- drivers/dma/xilinx/xilinx_dma.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index cf47347a1bc6..4e223d094433 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -1895,14 +1895,15 @@ static struct dma_async_tx_descriptor *xilinx_dma_prep_dma_cyclic( reg |= XILINX_DMA_CR_CYCLIC_BD_EN_MASK; dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg); + segment = list_last_entry(&desc->segments, + struct xilinx_axidma_tx_segment, + node); + segment->hw.next_desc = (u32) head_segment->phys; + /* For the last DMA_MEM_TO_DEV transfer, set EOP */ if (direction == DMA_MEM_TO_DEV) { head_segment->hw.control |= XILINX_DMA_BD_SOP; - segment = list_last_entry(&desc->segments, - struct xilinx_axidma_tx_segment, - node); segment->hw.control |= XILINX_DMA_BD_EOP; - segment->hw.next_desc = (u32) head_segment->phys; } return &desc->async_tx; -- 2.20.1