ar71xx: ag71xx: check PHY IDs before accessing the switch registers

SVN-Revision: 29541

diff --git a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar7240.c b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar7240.c
index ffc4948587c3da116eba090f0e6ac22b33272f73..c0eca4ae41f742d9597a97b50389e00df1cdeaab 100644 (file)
--- a/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar7240.c
+++ b/target/linux/ar71xx/files/drivers/net/ag71xx/ag71xx_ar7240.c
@@ -852,6 +852,14 @@ static struct ar7240sw *ar7240_probe(struct ag71xx *ag)
        u8 ver;
        int i;
 
+       phy_id1 = ar7240sw_phy_read(mii, 0, MII_PHYSID1);
+       phy_id2 = ar7240sw_phy_read(mii, 0, MII_PHYSID2);
+       if (phy_id1 != AR7240_PHY_ID1 || phy_id2 != AR7240_PHY_ID2) {
+               pr_err("%s: unknown phy id '%04x:%04x'\n",
+                      ag->dev->name, phy_id1, phy_id2);
+               return NULL;
+       }
+
        as = kzalloc(sizeof(*as), GFP_KERNEL);
        if (!as)
                return NULL;
@@ -859,7 +867,6 @@ static struct ar7240sw *ar7240_probe(struct ag71xx *ag)
        as->mii_bus = mii;
 
        ctrl = ar7240sw_reg_read(mii, AR7240_REG_MASK_CTRL);
-
        ver = (ctrl >> AR7240_MASK_CTRL_VERSION_S) & AR7240_MASK_CTRL_VERSION_M;
        if (ver != 1) {
                pr_err("%s: unsupported chip, ctrl=%08x\n",
@@ -867,14 +874,6 @@ static struct ar7240sw *ar7240_probe(struct ag71xx *ag)
                return NULL;
        }
 
-       phy_id1 = ar7240sw_phy_read(mii, 0, MII_PHYSID1);
-       phy_id2 = ar7240sw_phy_read(mii, 0, MII_PHYSID2);
-       if (phy_id1 != AR7240_PHY_ID1 || phy_id2 != AR7240_PHY_ID2) {
-               pr_err("%s: unknown phy id '%04x:%04x'\n",
-                      ag->dev->name, phy_id1, phy_id2);
-               return NULL;
-       }
-
        swdev = &as->swdev;
        swdev->name = "AR7240 built-in switch";
        swdev->ports = AR7240_NUM_PORTS - 1;