diff options
author | Paul Mackerras <paulus@samba.org> | 2008-12-03 20:11:06 +1100 |
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committer | Paul Mackerras <paulus@samba.org> | 2008-12-03 20:11:06 +1100 |
commit | 527491885554002837b5742202adc0ab5f536e54 (patch) | |
tree | 6d9c44776e0b4368eccd414b92b957fac3c5a4c6 /drivers/spi/au1550_spi.c | |
parent | cea555d384b85271035814c5adad23e6c7fc5d2a (diff) | |
parent | 2434bbb30e79468c49cff3cff6005236f55ed188 (diff) | |
download | linux-next-527491885554002837b5742202adc0ab5f536e54.tar.gz |
Merge branch 'merge'
Diffstat (limited to 'drivers/spi/au1550_spi.c')
-rw-r--r-- | drivers/spi/au1550_spi.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/drivers/spi/au1550_spi.c b/drivers/spi/au1550_spi.c index 87b73e0169c5..b02f25c702fd 100644 --- a/drivers/spi/au1550_spi.c +++ b/drivers/spi/au1550_spi.c @@ -369,10 +369,23 @@ static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t) dma_rx_addr = t->rx_dma; /* - * check if buffers are already dma mapped, map them otherwise + * check if buffers are already dma mapped, map them otherwise: + * - first map the TX buffer, so cache data gets written to memory + * - then map the RX buffer, so that cache entries (with + * soon-to-be-stale data) get removed * use rx buffer in place of tx if tx buffer was not provided * use temp rx buffer (preallocated or realloc to fit) for rx dma */ + if (t->tx_buf) { + if (t->tx_dma == 0) { /* if DMA_ADDR_INVALID, map it */ + dma_tx_addr = dma_map_single(hw->dev, + (void *)t->tx_buf, + t->len, DMA_TO_DEVICE); + if (dma_mapping_error(hw->dev, dma_tx_addr)) + dev_err(hw->dev, "tx dma map error\n"); + } + } + if (t->rx_buf) { if (t->rx_dma == 0) { /* if DMA_ADDR_INVALID, map it */ dma_rx_addr = dma_map_single(hw->dev, @@ -396,15 +409,8 @@ static int au1550_spi_dma_txrxb(struct spi_device *spi, struct spi_transfer *t) dma_sync_single_for_device(hw->dev, dma_rx_addr, t->len, DMA_FROM_DEVICE); } - if (t->tx_buf) { - if (t->tx_dma == 0) { /* if DMA_ADDR_INVALID, map it */ - dma_tx_addr = dma_map_single(hw->dev, - (void *)t->tx_buf, - t->len, DMA_TO_DEVICE); - if (dma_mapping_error(hw->dev, dma_tx_addr)) - dev_err(hw->dev, "tx dma map error\n"); - } - } else { + + if (!t->tx_buf) { dma_sync_single_for_device(hw->dev, dma_rx_addr, t->len, DMA_BIDIRECTIONAL); hw->tx = hw->rx; |