diff options
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c')
-rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c index 90383abafa66..f5581db0ba9b 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c @@ -218,11 +218,18 @@ static void dwmac1000_dump_dma_regs(void __iomem *ioaddr, u32 *reg_space) readl(ioaddr + DMA_BUS_MODE + i * 4); } -static void dwmac1000_get_hw_feature(void __iomem *ioaddr, - struct dma_features *dma_cap) +static int dwmac1000_get_hw_feature(void __iomem *ioaddr, + struct dma_features *dma_cap) { u32 hw_cap = readl(ioaddr + DMA_HW_FEATURE); + if (!hw_cap) { + /* 0x00000000 is the value read on old hardware that does not + * implement this register + */ + return -EOPNOTSUPP; + } + dma_cap->mbps_10_100 = (hw_cap & DMA_HW_FEAT_MIISEL); dma_cap->mbps_1000 = (hw_cap & DMA_HW_FEAT_GMIISEL) >> 1; dma_cap->half_duplex = (hw_cap & DMA_HW_FEAT_HDSEL) >> 2; @@ -252,6 +259,8 @@ static void dwmac1000_get_hw_feature(void __iomem *ioaddr, dma_cap->number_tx_channel = (hw_cap & DMA_HW_FEAT_TXCHCNT) >> 22; /* Alternate (enhanced) DESC mode */ dma_cap->enh_desc = (hw_cap & DMA_HW_FEAT_ENHDESSEL) >> 24; + + return 0; } static void dwmac1000_rx_watchdog(void __iomem *ioaddr, u32 riwt, |