[PATCH net,stable 1/1] net: fec: add defer probe for of_get_mac_address

[Andy Duan]

If MAC address read from nvmem efuse by calling .of_get_mac_address(),
but nvmem efuse is registerred later than the driver, then it
return -EPROBE_DEFER value. So modify the driver to support
defer probe when read MAC address from nvmem efuse.

Signed-off-by: Fugang Duan <fugang.d...@nxp.com>
---
 drivers/net/ethernet/freescale/fec_main.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c 
b/drivers/net/ethernet/freescale/fec_main.c
index 848defa..a76b609 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -1634,7 +1634,7 @@ static int fec_enet_rx_napi(struct napi_struct *napi, int 
budget)
 }
 
 /* ------------------------------------------------------------------------- */
-static void fec_get_mac(struct net_device *ndev)
+static int fec_get_mac(struct net_device *ndev)
 {
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct fec_platform_data *pdata = dev_get_platdata(&fep->pdev->dev);
@@ -1657,6 +1657,8 @@ static void fec_get_mac(struct net_device *ndev)
                        const char *mac = of_get_mac_address(np);
                        if (!IS_ERR(mac))
                                iap = (unsigned char *) mac;
+                       else if (PTR_ERR(mac) == -EPROBE_DEFER)
+                               return -EPROBE_DEFER;
                }
        }
 
@@ -1693,7 +1695,7 @@ static void fec_get_mac(struct net_device *ndev)
                eth_hw_addr_random(ndev);
                netdev_info(ndev, "Using random MAC address: %pM\n",
                            ndev->dev_addr);
-               return;
+               return 0;
        }
 
        memcpy(ndev->dev_addr, iap, ETH_ALEN);
@@ -1701,6 +1703,8 @@ static void fec_get_mac(struct net_device *ndev)
        /* Adjust MAC if using macaddr */
        if (iap == macaddr)
                 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->dev_id;
+
+       return 0;
 }
 
 /* ------------------------------------------------------------------------- */
@@ -3146,7 +3150,10 @@ static int fec_enet_init(struct net_device *ndev)
        memset(cbd_base, 0, bd_size);
 
        /* Get the Ethernet address */
-       fec_get_mac(ndev);
+       ret = fec_get_mac(ndev);
+       if (ret)
+               return ret;
+
        /* make sure MAC we just acquired is programmed into the hw */
        fec_set_mac_address(ndev, NULL);
 
-- 
2.7.4