linux-kernel - [PATCH v2 2/2] dmaengine: ptdma: handle the cases based on DMA is complete

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Date:   Wed, 2 Feb 2022 09:14:40 -0600
From:   Sanjay R Mehta <Sanju.Mehta@....com>
To:     <vkoul@...nel.org>
CC:     <gregkh@...uxfoundation.org>, <dan.j.williams@...el.com>,
        <Thomas.Lendacky@....com>, <robh@...nel.org>,
        <mchehab+samsung@...nel.org>, <davem@...emloft.net>,
        <linux-kernel@...r.kernel.org>, <dmaengine@...r.kernel.org>,
        Sanjay R Mehta <sanju.mehta@....com>
Subject: [PATCH v2 2/2] dmaengine: ptdma: handle the cases based on DMA is complete

From: Sanjay R Mehta <sanju.mehta@....com>

There is a need to segregate the cases when DMA is complete or not.
In case if DMA is already complete there is no need to handle it
again and gracefully exit from the function.

Signed-off-by: Sanjay R Mehta <sanju.mehta@....com>
---
 drivers/dma/ptdma/ptdma-dmaengine.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/ptdma/ptdma-dmaengine.c b/drivers/dma/ptdma/ptdma-dmaengine.c
index e38dca4..91b93e8 100644
--- a/drivers/dma/ptdma/ptdma-dmaengine.c
+++ b/drivers/dma/ptdma/ptdma-dmaengine.c
@@ -100,12 +100,17 @@ static struct pt_dma_desc *pt_handle_active_desc(struct pt_dma_chan *chan,
 		spin_lock_irqsave(&chan->vc.lock, flags);
 
 		if (desc) {
-			if (desc->status != DMA_ERROR)
-				desc->status = DMA_COMPLETE;
-
-			dma_cookie_complete(tx_desc);
-			dma_descriptor_unmap(tx_desc);
-			list_del(&desc->vd.node);
+			if (desc->status != DMA_COMPLETE) {
+				if (desc->status != DMA_ERROR)
+					desc->status = DMA_COMPLETE;
+
+				dma_cookie_complete(tx_desc);
+				dma_descriptor_unmap(tx_desc);
+				list_del(&desc->vd.node);
+			} else {
+				/* Don't handle it twice */
+				tx_desc = NULL;
+			}
 		}
 
 		desc = pt_next_dma_desc(chan);
-- 
2.7.4