The sh_eth_close() resets the MAC and then calls phy_stop() so that mdio read access result is incorrect without any error according to kernel trace like below: ifconfig-216 [003] .n.. 109.133124: mdio_access: ee700000.ethernet-ffffffff read phy:0x01 reg:0x00 val:0xffff To fix the issue, this patch adds a condition and set the RMII mode regiseter in sh_eth_dev_exit() for some SoCs. Note that when I have tried to move the sh_eth_dev_exit() calling after phy_stop() on sh_eth_close(), but it gets worse. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> --- drivers/net/ethernet/renesas/sh_eth.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c index e33af37..106ae90 100644 --- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -1596,6 +1596,10 @@ static void sh_eth_dev_exit(struct net_device *ndev) /* Set MAC address again */ update_mac_address(ndev); + + /* Set the mode again if required */ + if (mdp->cd->rmiimode) + sh_eth_write(ndev, 0x1, RMIIMODE); } static void sh_eth_rx_csum(struct sk_buff *skb) -- 2.7.4
