net: phy: smsc: force all capable mode if the phy is started in powerdown mode

A SMSC PHY in power down mode can't be used.
If a SMSC PHY is in this mode in the config_init
stage, the mode "all capable" is set. So the PHY
could then be used.

Signed-off-by: Philippe Reynes <tremyfr@yahoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 30 insertions, 1 deletions

diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
index 16dceed29d8c..ef883e3048c0 100644
--- a/drivers/net/phy/smsc.c
+++ b/drivers/net/phy/smsc.c
@@ -43,7 +43,31 @@ static int smsc_phy_ack_interrupt(struct phy_device *phydev)
 
 static int smsc_phy_config_init(struct phy_device *phydev)
 {
-        int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
+        int rc = phy_read(phydev, MII_LAN83C185_SPECIAL_MODES);
+        if (rc < 0)
+                return rc;
+
+        /* If the SMSC PHY is in power down mode, then set it
+         * in all capable mode before using it.
+         */
+        if ((rc & MII_LAN83C185_MODE_MASK) == MII_LAN83C185_MODE_POWERDOWN) {
+                int timeout = 50000;
+
+                /* set "all capable" mode and reset the phy */
+                rc |= MII_LAN83C185_MODE_ALL;
+                phy_write(phydev, MII_LAN83C185_SPECIAL_MODES, rc);
+                phy_write(phydev, MII_BMCR, BMCR_RESET);
+
+                /* wait end of reset (max 500 ms) */
+                do {
+                        udelay(10);
+                        if (timeout-- == 0)
+                                return -1;
+                        rc = phy_read(phydev, MII_BMCR);
+                } while (rc & BMCR_RESET);
+        }
+
+        rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
         if (rc < 0)
                 return rc;
 
diff --git a/include/linux/smscphy.h b/include/linux/smscphy.h
index ce718cbce435..f4bf16e16e16 100644
--- a/include/linux/smscphy.h
+++ b/include/linux/smscphy.h
@@ -4,6 +4,7 @@
 #define MII_LAN83C185_ISF 29 /* Interrupt Source Flags */
 #define MII_LAN83C185_IM  30 /* Interrupt Mask */
 #define MII_LAN83C185_CTRL_STATUS 17 /* Mode/Status Register */
+#define MII_LAN83C185_SPECIAL_MODES 18 /* Special Modes Register */
 
 #define MII_LAN83C185_ISF_INT1 (1<<1) /* Auto-Negotiation Page Received */
 #define MII_LAN83C185_ISF_INT2 (1<<2) /* Parallel Detection Fault */
@@ -22,4 +23,8 @@
 #define MII_LAN83C185_EDPWRDOWN (1 << 13) /* EDPWRDOWN */
 #define MII_LAN83C185_ENERGYON  (1 << 1)  /* ENERGYON */
 
+#define MII_LAN83C185_MODE_MASK      0xE0
+#define MII_LAN83C185_MODE_POWERDOWN 0xC0 /* Power Down mode */
+#define MII_LAN83C185_MODE_ALL       0xE0 /* All capable mode */
+
 #endif /* __LINUX_SMSCPHY_H__ */