diff --git a/drivers/spi/pxa2xx_spi.c b/drivers/spi/pxa2xx_spi.c index dae87b1a4c6e..cf12f2d84be2 100644 --- a/drivers/spi/pxa2xx_spi.c +++ b/drivers/spi/pxa2xx_spi.c @@ -352,21 +352,21 @@ static int map_dma_buffers(struct driver_data *drv_data) } else drv_data->tx_map_len = drv_data->len; - /* Stream map the rx buffer */ - drv_data->rx_dma = dma_map_single(dev, drv_data->rx, - drv_data->rx_map_len, - DMA_FROM_DEVICE); - if (dma_mapping_error(dev, drv_data->rx_dma)) + /* Stream map the tx buffer. Always do DMA_TO_DEVICE first + * so we flush the cache *before* invalidating it, in case + * the tx and rx buffers overlap. + */ + drv_data->tx_dma = dma_map_single(dev, drv_data->tx, + drv_data->tx_map_len, DMA_TO_DEVICE); + if (dma_mapping_error(dev, drv_data->tx_dma)) return 0; - /* Stream map the tx buffer */ - drv_data->tx_dma = dma_map_single(dev, drv_data->tx, - drv_data->tx_map_len, - DMA_TO_DEVICE); - - if (dma_mapping_error(dev, drv_data->tx_dma)) { - dma_unmap_single(dev, drv_data->rx_dma, + /* Stream map the rx buffer */ + drv_data->rx_dma = dma_map_single(dev, drv_data->rx, drv_data->rx_map_len, DMA_FROM_DEVICE); + if (dma_mapping_error(dev, drv_data->rx_dma)) { + dma_unmap_single(dev, drv_data->tx_dma, + drv_data->tx_map_len, DMA_TO_DEVICE); return 0; }