From: Ming Lei <tom.leiming@xxxxxxxxx> If buffer is to be accessed by cpu after dma transfer is over, but between dma mapping and dma unmapping, we should use dma_sync_single_for_cpu to sync the buffer between cpu with device. And dma_sync_single_for_device is used to let device gain the buffer again. Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx> --- drivers/net/wireless/ath/ath9k/recv.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index a3fe6e1..96f5d83 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -694,7 +694,7 @@ static bool ath_edma_get_buffers(struct ath_softc *sc, bf = SKB_CB_ATHBUF(skb); BUG_ON(!bf); - dma_sync_single_for_device(sc->dev, bf->bf_buf_addr, + dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr, common->rx_bufsize, DMA_FROM_DEVICE); ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data); @@ -808,7 +808,7 @@ static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc, * 1. accessing the frame * 2. requeueing the same buffer to h/w */ - dma_sync_single_for_device(sc->dev, bf->bf_buf_addr, + dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr, common->rx_bufsize, DMA_FROM_DEVICE); -- 1.6.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html