From d9ec46416de5ef83220f1c7010ee0f5d1be1d753 Mon Sep 17 00:00:00 2001 From: Sylvain Lesne Date: Mon, 18 Sep 2017 13:08:00 +0200 Subject: [PATCH] dmaengine: altera: fix response FIFO emptying Commit 6084fc2ec478 ("dmaengine: altera: Use macros instead of structs to describe the registers") introduced a minus sign before a register offset. This leads to soft-locks of the DMA controller, since reading the last status byte is required to pop the response from the FIFO. Failing to do so will lead to a full FIFO, which means that the DMA controller will stop processing descriptors. Signed-off-by: Sylvain Lesne Reviewed-by: Stefan Roese Signed-off-by: Vinod Koul --- drivers/dma/altera-msgdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/dma/altera-msgdma.c b/drivers/dma/altera-msgdma.c index 32905d5606ac..35cbf2365f68 100644 --- a/drivers/dma/altera-msgdma.c +++ b/drivers/dma/altera-msgdma.c @@ -698,7 +698,7 @@ static void msgdma_tasklet(unsigned long data) * bits. So we need to just drop these values. */ size = ioread32(mdev->resp + MSGDMA_RESP_BYTES_TRANSFERRED); - status = ioread32(mdev->resp - MSGDMA_RESP_STATUS); + status = ioread32(mdev->resp + MSGDMA_RESP_STATUS); msgdma_complete_descriptor(mdev); msgdma_chan_desc_cleanup(mdev);