[PATCH v5 2/5] dma: mmp_pdma: don't clear DCMD_ENDIRQEN at end of pending chain

Daniel Mack zonque at gmail.com
Wed Aug 21 08:08:55 EDT 2013


In order to fully support multiple transactions per channel, we need to
assure we get an interrupt for each completed transaction. That flags
bit is also our only way to tell at which descriptor a transaction ends.

So, remove the manual clearing of that bit, and then inline the only
remaining command that is left in append_pending_queue() for better
readability.

Signed-off-by: Daniel Mack <zonque at gmail.com>
---
 drivers/dma/mmp_pdma.c | 22 ++--------------------
 1 file changed, 2 insertions(+), 20 deletions(-)

diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
index 9929f85..31e9a71 100644
--- a/drivers/dma/mmp_pdma.c
+++ b/drivers/dma/mmp_pdma.c
@@ -279,25 +279,6 @@ static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 	spin_unlock_irqrestore(&pdev->phy_lock, flags);
 }
 
-/* desc->tx_list ==> pending list */
-static void append_pending_queue(struct mmp_pdma_chan *chan,
-					struct mmp_pdma_desc_sw *desc)
-{
-	struct mmp_pdma_desc_sw *tail =
-				to_mmp_pdma_desc(chan->chain_pending.prev);
-
-	if (list_empty(&chan->chain_pending))
-		goto out_splice;
-
-	/* one irq per queue, even appended */
-	tail->desc.ddadr = desc->async_tx.phys;
-	tail->desc.dcmd &= ~DCMD_ENDIRQEN;
-
-	/* softly link to pending list */
-out_splice:
-	list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
-}
-
 /**
  * start_pending_queue - transfer any pending transactions
  * pending list ==> running list
@@ -360,7 +341,8 @@ static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx)
 		cookie = dma_cookie_assign(&child->async_tx);
 	}
 
-	append_pending_queue(chan, desc);
+	/* softly link to pending list - desc->tx_list ==> pending list */
+	list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
 
 	spin_unlock_irqrestore(&chan->desc_lock, flags);
 
-- 
1.8.3.1




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