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| author | Qipan Li <Qipan.Li@csr.com> | 2014-04-14 14:30:01 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-04-14 21:04:59 +0100 |
| commit | bf83fd6402a856eeb9a22c364c50ccf9bbdf9b17 (patch) | |
| tree | 905fe272f9d08fff5e4483294b8e96c6b26e59e6 /drivers/spi/spi-sirf.c | |
| parent | d77ec5df47696300b9498e6973dcc34b40de8d27 (diff) | |
| download | linux-bf83fd6402a856eeb9a22c364c50ccf9bbdf9b17.tar.gz linux-bf83fd6402a856eeb9a22c364c50ccf9bbdf9b17.tar.bz2 linux-bf83fd6402a856eeb9a22c364c50ccf9bbdf9b17.zip | |
spi: sirf: fix spi full-duplex DMA transferring issue
sometimes t->tx can be equal with t->rx. for example, spidev will make
tx and rx point to spidev->buffer at the same time. currently, for this
case, we map the buffer BIDIRECTION to fix the cache consistency.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/spi/spi-sirf.c')
| -rw-r--r-- | drivers/spi/spi-sirf.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/spi/spi-sirf.c b/drivers/spi/spi-sirf.c index 3c12f396d96a..0c039d4542a5 100644 --- a/drivers/spi/spi-sirf.c +++ b/drivers/spi/spi-sirf.c @@ -383,7 +383,8 @@ static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t) struct dma_async_tx_descriptor *rx_desc, *tx_desc; sspi->dst_start = dma_map_single(&spi->dev, - sspi->rx, t->len, DMA_FROM_DEVICE); + sspi->rx, t->len, (t->tx_buf != t->rx_buf) ? + DMA_FROM_DEVICE : DMA_BIDIRECTIONAL); rx_desc = dmaengine_prep_slave_single(sspi->rx_chan, sspi->dst_start, t->len, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); @@ -391,7 +392,9 @@ static int spi_sirfsoc_transfer(struct spi_device *spi, struct spi_transfer *t) rx_desc->callback_param = &sspi->rx_done; sspi->src_start = dma_map_single(&spi->dev, - (void *)sspi->tx, t->len, DMA_TO_DEVICE); + (void *)sspi->tx, t->len, + (t->tx_buf != t->rx_buf) ? + DMA_TO_DEVICE : DMA_BIDIRECTIONAL); tx_desc = dmaengine_prep_slave_single(sspi->tx_chan, sspi->src_start, t->len, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |