[PATCH 4.19 32/90] dmaengine: sprd: Fix block length overflow

[Greg Kroah-Hartman]

[ Upstream commit 89d03b3c126d683f7b2cd5b07178493993d12448 ]

The maximum value of block length is 0xffff, so if the configured transfer length
is more than 0xffff, that will cause block length overflow to lead a configuration
error.

Thus we can set block length as the maximum burst length to avoid this issue, since
the maximum burst length will not be a big value which is more than 0xffff.

Signed-off-by: Eric Long <eric.long@xxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/dma/sprd-dma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index 55df0d41355b..1ed1c7efa288 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -663,7 +663,7 @@ static int sprd_dma_fill_desc(struct dma_chan *chan,
 	temp |= slave_cfg->src_maxburst & SPRD_DMA_FRG_LEN_MASK;
 	hw->frg_len = temp;
 
-	hw->blk_len = len & SPRD_DMA_BLK_LEN_MASK;
+	hw->blk_len = slave_cfg->src_maxburst & SPRD_DMA_BLK_LEN_MASK;
 	hw->trsc_len = len & SPRD_DMA_TRSC_LEN_MASK;
 
 	temp = (dst_step & SPRD_DMA_TRSF_STEP_MASK) << SPRD_DMA_DEST_TRSF_STEP_OFFSET;
-- 
2.20.1