[PATCH 1/2] dma: axi-dmac: Only use hardware cyclic mode for single segment transfers

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In hardware cyclic mode the submitted segment is repeated. This means
hardware cyclic mode can only be used if the transfer has a single segment.

Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
---
 drivers/dma/dma-axi-dmac.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c
index 7f0b9aa15867..eb289aa187dd 100644
--- a/drivers/dma/dma-axi-dmac.c
+++ b/drivers/dma/dma-axi-dmac.c
@@ -220,9 +220,11 @@ static void axi_dmac_start_transfer(struct axi_dmac_chan *chan)
 
 	/*
 	 * If the hardware supports cyclic transfers and there is no callback to
-	 * call, enable hw cyclic mode to avoid unnecessary interrupts.
+	 * call and only a single segment, enable hw cyclic mode to avoid
+	 * unnecessary interrupts.
 	 */
-	if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback)
+	if (chan->hw_cyclic && desc->cyclic && !desc->vdesc.tx.callback &&
+		desc->num_sgs == 1)
 		flags |= AXI_DMAC_FLAG_CYCLIC;
 
 	axi_dmac_write(dmac, AXI_DMAC_REG_X_LENGTH, sg->x_len - 1);
-- 
2.11.0

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