diff options
| author | Ming Lei <tom.leiming@gmail.com> | 2010-05-15 18:25:40 +0800 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2010-06-04 14:55:09 -0400 |
| commit | ce9426d1908001fb2f7b0152fbe4184bbc0c7b68 (patch) | |
| tree | 42389f116a18a2ba8c3d7b20f52d591766bb9602 /drivers/net/wireless/ath/ath9k/recv.c | |
| parent | 26b36cfefaf2be98b225e3c1a399edb0daf52ddd (diff) | |
| download | lwn-ce9426d1908001fb2f7b0152fbe4184bbc0c7b68.tar.gz lwn-ce9426d1908001fb2f7b0152fbe4184bbc0c7b68.zip | |
ath9k: fix dma sync in rx path
If buffer is to be accessed by cpu after dma 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.
v2: Felix pointed out dma_sync_single_for_device is needed to return
buffer to device if an unsuccessful status bit check is found.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Acked-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/recv.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/recv.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index 1618f8fe195d..d373364ef8a9 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -700,12 +700,16 @@ 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); - if (ret == -EINPROGRESS) + if (ret == -EINPROGRESS) { + /*let device gain the buffer again*/ + dma_sync_single_for_device(sc->dev, bf->bf_buf_addr, + common->rx_bufsize, DMA_FROM_DEVICE); return false; + } __skb_unlink(skb, &rx_edma->rx_fifo); if (ret == -EINVAL) { @@ -814,7 +818,7 @@ 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); |