KSZ8851-SNL: Add support for EEPROM MAC address

Add support for reading the MAC address from the system registers if there
is an EEPROM present. This involves caching the KS_CCR register for later
use (will also be useful for ETHTOOL support) and adding a print to say
that there is an EEPROM present.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 34 insertions, 7 deletions

diff --git a/drivers/net/ethernet/micrel/ks8851.c b/drivers/net/ethernet/micrel/ks8851.c
index f56743a28fc0..d1669bcd4b4d 100644
--- a/drivers/net/ethernet/micrel/ks8851.c
+++ b/drivers/net/ethernet/micrel/ks8851.c
@@ -367,21 +367,47 @@ static int ks8851_write_mac_addr(struct net_device *dev)
 }
 
 /**
+ * ks8851_read_mac_addr - read mac address from device registers
+ * @dev: The network device
+ *
+ * Update our copy of the KS8851 MAC address from the registers of @dev.
+*/
+static void ks8851_read_mac_addr(struct net_device *dev)
+{
+        struct ks8851_net *ks = netdev_priv(dev);
+        int i;
+
+        mutex_lock(&ks->lock);
+
+        for (i = 0; i < ETH_ALEN; i++)
+                dev->dev_addr[i] = ks8851_rdreg8(ks, KS_MAR(i));
+
+        mutex_unlock(&ks->lock);
+}
+
+/**
  * ks8851_init_mac - initialise the mac address
  * @ks: The device structure
  *
  * Get or create the initial mac address for the device and then set that
- * into the station address register. Currently we assume that the device
- * does not have a valid mac address in it, and so we use random_ether_addr()
+ * into the station address register. If there is an EEPROM present, then
+ * we try that. If no valid mac address is found we use random_ether_addr()
  * to create a new one.
- *
- * In future, the driver should check to see if the device has an EEPROM
- * attached and whether that has a valid ethernet address in it.
  */
 static void ks8851_init_mac(struct ks8851_net *ks)
 {
         struct net_device *dev = ks->netdev;
 
+        /* first, try reading what we've got already */
+        if (ks->rc_ccr & CCR_EEPROM) {
+                ks8851_read_mac_addr(dev);
+                if (is_valid_ether_addr(dev->dev_addr))
+                        return;
+
+                netdev_err(ks->netdev, "invalid mac address read %pM\n",
+                                dev->dev_addr);
+        }
+
         random_ether_addr(dev->dev_addr);
         ks8851_write_mac_addr(dev);
 }
@@ -1674,9 +1700,10 @@ static int __devinit ks8851_probe(struct spi_device *spi)
                 goto err_netdev;
         }
 
-        netdev_info(ndev, "revision %d, MAC %pM, IRQ %d\n",
+        netdev_info(ndev, "revision %d, MAC %pM, IRQ %d, %s EEPROM\n",
                     CIDER_REV_GET(ks8851_rdreg16(ks, KS_CIDER)),
-                    ndev->dev_addr, ndev->irq);
+                    ndev->dev_addr, ndev->irq,
+                    ks->rc_ccr & CCR_EEPROM ? "has" : "no");
 
         return 0;