dmaengine: xgene-dma: Fix double IRQ issue by setting IRQ_DISABLE_UNLAZY flag

For interrupt controller that doesn't support irq_disable and hardware
with level interrupt, an extra interrupt can be pending. This patch fixes
the issue by setting IRQ_DISABLE_UNLAZY flag for the interrupt line.

Reference: http://git.kernel.org/tip/e9849777d0e27cdd2902805be51da73e7c79578cSigned-off-by: Rameshwar Prasad Sahu <rsahu@apm.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/xgene-dma.c

@@ -29,6 +29,7 @@
 #include <linux/dmapool.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
 
@@ -1610,6 +1611,7 @@ static int xgene_dma_request_irqs(struct xgene_dma *pdma)
 	/* Register DMA channel rx irq */
 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
 		chan = &pdma->chan[i];
+		irq_set_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
 		ret = devm_request_irq(chan->dev, chan->rx_irq,
 				       xgene_dma_chan_ring_isr,
 				       0, chan->name, chan);
@@ -1620,6 +1622,7 @@ static int xgene_dma_request_irqs(struct xgene_dma *pdma)
 
 			for (j = 0; j < i; j++) {
 				chan = &pdma->chan[i];
+				irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
 				devm_free_irq(chan->dev, chan->rx_irq, chan);
 			}
 
@@ -1640,6 +1643,7 @@ static void xgene_dma_free_irqs(struct xgene_dma *pdma)
 
 	for (i = 0; i < XGENE_DMA_MAX_CHANNEL; i++) {
 		chan = &pdma->chan[i];
+		irq_clear_status_flags(chan->rx_irq, IRQ_DISABLE_UNLAZY);
 		devm_free_irq(chan->dev, chan->rx_irq, chan);
 	}
 }