[PATCH] DMAEngine: sirf: lock the shared registers access in sirfsoc_dma_terminate_all

[Barry Song]

From: Barry Song <Baohua.Song at csr.com>

Just like Russell pointed out in "DMAEngine: sirf: add DMA
pause/resume support" at
http://www.spinics.net/lists/arm-kernel/msg212496.html
here I find sirfsoc_dma_terminate_all() has same problem,
so move the locking to the front of registers access.

Signed-off-by: Barry Song <Baohua.Song at csr.com>
Cc: Russell King <linux at arm.linux.org.uk>
---
 drivers/dma/sirf-dma.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/dma/sirf-dma.c b/drivers/dma/sirf-dma.c
index 623f195..df8e2e6 100644
--- a/drivers/dma/sirf-dma.c
+++ b/drivers/dma/sirf-dma.c
@@ -291,6 +291,8 @@ static int sirfsoc_dma_terminate_all(struct sirfsoc_dma_chan *schan)
 	int cid = schan->chan.chan_id;
 	unsigned long flags;
 
+	spin_lock_irqsave(&schan->lock, flags);
+
 	if (!sdma->is_marco) {
 		writel_relaxed(readl_relaxed(sdma->base + SIRFSOC_DMA_INT_EN) &
 			~(1 << cid), sdma->base + SIRFSOC_DMA_INT_EN);
@@ -305,9 +307,9 @@ static int sirfsoc_dma_terminate_all(struct sirfsoc_dma_chan *schan)
 
 	writel_relaxed(1 << cid, sdma->base + SIRFSOC_DMA_CH_VALID);
 
-	spin_lock_irqsave(&schan->lock, flags);
 	list_splice_tail_init(&schan->active, &schan->free);
 	list_splice_tail_init(&schan->queued, &schan->free);
+
 	spin_unlock_irqrestore(&schan->lock, flags);
 
 	return 0;
-- 
1.7.5.4



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