From 884485e1f12dcd39390f042e772cdbefc9ebb750 Mon Sep 17 00:00:00 2001 From: Russell King - ARM Linux Date: Tue, 6 Mar 2012 22:34:46 +0000 Subject: dmaengine: consolidate assignment of DMA cookies Everyone deals with assigning DMA cookies in the same way (it's part of the API so they should be), so lets consolidate the common code into a helper function to avoid this duplication. Signed-off-by: Russell King Tested-by: Linus Walleij Reviewed-by: Linus Walleij Acked-by: Jassi Brar [imx-sdma.c & mxs-dma.c] Tested-by: Shawn Guo Signed-off-by: Vinod Koul --- drivers/dma/dmaengine.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'drivers/dma/dmaengine.h') diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h index 968570dde2eb..7692c8644045 100644 --- a/drivers/dma/dmaengine.h +++ b/drivers/dma/dmaengine.h @@ -7,4 +7,24 @@ #include +/** + * dma_cookie_assign - assign a DMA engine cookie to the descriptor + * @tx: descriptor needing cookie + * + * Assign a unique non-zero per-channel cookie to the descriptor. + * Note: caller is expected to hold a lock to prevent concurrency. + */ +static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx) +{ + struct dma_chan *chan = tx->chan; + dma_cookie_t cookie; + + cookie = chan->cookie + 1; + if (cookie < DMA_MIN_COOKIE) + cookie = DMA_MIN_COOKIE; + tx->cookie = chan->cookie = cookie; + + return cookie; +} + #endif -- cgit v1.2.3