[PATCH 08/11] USB: musb: clear the Blackfin interrupt pending bits early in the ISR

[Mike Frysinger]

From: Cliff Cai <cliff.cai@xxxxxxxxxx>

If we clear the interrupt pending bits at the end, we sometimes return too
fast and have the same interrupt assert itself.  There is no way in a
Blackfin system to force a sync of this state, so the hardware manual
instructs people to clear interrupt flags early in their ISR.

Signed-off-by: Cliff Cai <cliff.cai@xxxxxxxxxx>
Signed-off-by: Mike Frysinger <vapier@xxxxxxxxxx>
---
 drivers/usb/musb/musbhsdma.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c
index 5e83f96..c767387 100644
--- a/drivers/usb/musb/musbhsdma.c
+++ b/drivers/usb/musb/musbhsdma.c
@@ -259,6 +259,11 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data)
 	if (!int_hsdma)
 		goto done;
 
+#ifdef CONFIG_BLACKFIN
+	/* Clear DMA interrupt flags */
+	musb_writeb(mbase, MUSB_HSDMA_INTR, int_hsdma);
+#endif
+
 	for (bchannel = 0; bchannel < MUSB_HSDMA_CHANNELS; bchannel++) {
 		if (int_hsdma & (1 << bchannel)) {
 			musb_channel = (struct musb_dma_channel *)
@@ -324,11 +329,6 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data)
 		}
 	}
 
-#ifdef CONFIG_BLACKFIN
-	/* Clear DMA interrup flags */
-	musb_writeb(mbase, MUSB_HSDMA_INTR, int_hsdma);
-#endif
-
 	retval = IRQ_HANDLED;
 done:
 	spin_unlock_irqrestore(&musb->lock, flags);
-- 
1.6.5.rc1

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