b44: abort when no PHY is available at all

When the phy address is 31, this means that there is no PHY connected
to this MAC at all, no internal and no external PHY. Reading these PHY
registers causes a system reset on some routers.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/b44.c b/drivers/net/ethernet/broadcom/b44.c
index 5c05d15..09e9e97 100644 (file)
--- a/drivers/net/ethernet/broadcom/b44.c
+++ b/drivers/net/ethernet/broadcom/b44.c
@@ -2206,6 +2206,12 @@ static int b44_init_one(struct ssb_device *sdev,
                goto err_out_powerdown;
        }
 
+       if (bp->phy_addr == B44_PHY_ADDR_NO_PHY) {
+               dev_err(sdev->dev, "No PHY present on this MAC, aborting\n");
+               err = -ENODEV;
+               goto err_out_powerdown;
+       }
+
        bp->mii_if.dev = dev;
        bp->mii_if.mdio_read = b44_mii_read;
        bp->mii_if.mdio_write = b44_mii_write;

diff --git a/drivers/net/ethernet/broadcom/b44.h b/drivers/net/ethernet/broadcom/b44.h
index 57e5357..4b0c5d2 100644 (file)
--- a/drivers/net/ethernet/broadcom/b44.h
+++ b/drivers/net/ethernet/broadcom/b44.h
@@ -282,6 +282,7 @@ struct ring_info {
 
 #define B44_MCAST_TABLE_SIZE           32
 #define B44_PHY_ADDR_NO_LOCAL_PHY      30 /* no local phy regs */
+#define B44_PHY_ADDR_NO_PHY            31 /* no phy present at all */
 #define B44_MDC_RATIO                  5000000
 
 #define        B44_STAT_REG_DECLARE            \