Streaming DMA operates at already allocated memory and the mapping needs to be checked for errors with dma_mapping_error(). Calling it on the DMA address resulting from dma_alloc_coherent is wrong, because error is indicated by returning a NULL pointer as CPU address; The DMA address may not be set at all in that case. While fixing this I wondered why priv->[tr]x_mac_descrtable_dev appear to be unused. That's not the case, because they are used indirectly via a helper function defined in a header, so add a comment about this while we are at it. Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> --- drivers/net/designware.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/designware.c b/drivers/net/designware.c index 66f28b429dea..e7735a014cf4 100644 --- a/drivers/net/designware.c +++ b/drivers/net/designware.c @@ -480,18 +480,20 @@ struct dw_eth_dev *dwc_drv_probe(struct device *dev) dwc_version(dev, readl(&priv->mac_regs_p->version)); priv->dma_regs_p = base + DW_DMA_BASE_OFFSET; + /* [tr]x_mac_descrtable_dev will be used by the [tr]x_dma_addr helpers */ + priv->tx_mac_descrtable_cpu = dma_alloc_coherent( CONFIG_TX_DESCR_NUM * sizeof(struct dmamacdescr), &priv->tx_mac_descrtable_dev); - if (dma_mapping_error(dev, priv->tx_mac_descrtable_dev)) + if (!priv->tx_mac_descrtable_cpu) return ERR_PTR(-EFAULT); priv->rx_mac_descrtable_cpu = dma_alloc_coherent( CONFIG_RX_DESCR_NUM * sizeof(struct dmamacdescr), &priv->rx_mac_descrtable_dev); - if (dma_mapping_error(dev, priv->rx_mac_descrtable_dev)) + if (!priv->rx_mac_descrtable_cpu) return ERR_PTR(-EFAULT); priv->txbuffs = dma_alloc(TX_TOTAL_BUFSIZE); -- 2.39.5
