[PATCH 4.14 130/222] dmaengine: stm32-dma: fix incomplete configuration in cyclic mode

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Pierre Yves MORDRET <pierre-yves.mordret@xxxxxx>

commit e57cb3b3f10d005410f09d4598cc6d62b833f2b0 upstream.

When in cyclic mode, the configuration is updated after having started the
DMA hardware (STM32_DMA_SCR_EN) leading to incomplete configuration of
SMxAR registers.

Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@xxxxxx>
Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
Cc: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/dma/stm32-dma.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -429,6 +429,8 @@ static void stm32_dma_dump_reg(struct st
 	dev_dbg(chan2dev(chan), "SFCR:  0x%08x\n", sfcr);
 }
 
+static void stm32_dma_configure_next_sg(struct stm32_dma_chan *chan);
+
 static void stm32_dma_start_transfer(struct stm32_dma_chan *chan)
 {
 	struct stm32_dma_device *dmadev = stm32_dma_get_dev(chan);
@@ -471,6 +473,9 @@ static void stm32_dma_start_transfer(str
 	if (status)
 		stm32_dma_irq_clear(chan, status);
 
+	if (chan->desc->cyclic)
+		stm32_dma_configure_next_sg(chan);
+
 	stm32_dma_dump_reg(chan);
 
 	/* Start DMA */
@@ -564,8 +569,7 @@ static void stm32_dma_issue_pending(stru
 	if (vchan_issue_pending(&chan->vchan) && !chan->desc && !chan->busy) {
 		dev_dbg(chan2dev(chan), "vchan %p: issued\n", &chan->vchan);
 		stm32_dma_start_transfer(chan);
-		if (chan->desc->cyclic)
-			stm32_dma_configure_next_sg(chan);
+
 	}
 	spin_unlock_irqrestore(&chan->vchan.lock, flags);
 }