dmaengine: sprd: Fix block length overflow

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@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/sprd-dma.c

@@ -778,7 +778,7 @@ 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;