These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / net / phy / smsc.c

diff --git a/kernel/drivers/net/phy/smsc.c b/kernel/drivers/net/phy/smsc.c
index c0f6479..dc2da87 100644 (file)
--- a/kernel/drivers/net/phy/smsc.c
+++ b/kernel/drivers/net/phy/smsc.c
@@ -43,16 +43,25 @@ static int smsc_phy_ack_interrupt(struct phy_device *phydev)
 
 static int smsc_phy_config_init(struct phy_device *phydev)
 {
+       int __maybe_unused len;
+       struct device *dev __maybe_unused = &phydev->dev;
+       struct device_node *of_node __maybe_unused = dev->of_node;
        int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
+       int enable_energy = 1;
 
        if (rc < 0)
                return rc;
 
-       /* Enable energy detect mode for this SMSC Transceivers */
-       rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
-                      rc | MII_LAN83C185_EDPWRDOWN);
-       if (rc < 0)
-               return rc;
+       if (of_find_property(of_node, "smsc,disable-energy-detect", &len))
+               enable_energy = 0;
+
+       if (enable_energy) {
+               /* Enable energy detect mode for this SMSC Transceivers */
+               rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
+                              rc | MII_LAN83C185_EDPWRDOWN);
+               if (rc < 0)
+                       return rc;
+       }
 
        return smsc_phy_ack_interrupt(phydev);
 }
@@ -91,19 +100,18 @@ static int lan911x_config_init(struct phy_device *phydev)
 }
 
 /*
- * The LAN8710/LAN8720 requires a minimum of 2 link pulses within 64ms of each
- * other in order to set the ENERGYON bit and exit EDPD mode.  If a link partner
- * does send the pulses within this interval, the PHY will remained powered
- * down.
- *
- * This workaround will manually toggle the PHY on/off upon calls to read_status
- * in order to generate link test pulses if the link is down.  If a link partner
- * is present, it will respond to the pulses, which will cause the ENERGYON bit
- * to be set and will cause the EDPD mode to be exited.
+ * The LAN87xx suffers from rare absence of the ENERGYON-bit when Ethernet cable
+ * plugs in while LAN87xx is in Energy Detect Power-Down mode. This leads to
+ * unstable detection of plugging in Ethernet cable.
+ * This workaround disables Energy Detect Power-Down mode and waiting for
+ * response on link pulses to detect presence of plugged Ethernet cable.
+ * The Energy Detect Power-Down mode is enabled again in the end of procedure to
+ * save approximately 220 mW of power if cable is unplugged.
  */
 static int lan87xx_read_status(struct phy_device *phydev)
 {
        int err = genphy_read_status(phydev);
+       int i;
 
        if (!phydev->link) {
                /* Disable EDPD to wake up PHY */
@@ -116,8 +124,16 @@ static int lan87xx_read_status(struct phy_device *phydev)
                if (rc < 0)
                        return rc;
 
-               /* Sleep 64 ms to allow ~5 link test pulses to be sent */
-               msleep(64);
+               /* Wait max 640 ms to detect energy */
+               for (i = 0; i < 64; i++) {
+                       /* Sleep to allow link test pulses to be sent */
+                       msleep(10);
+                       rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
+                       if (rc < 0)
+                               return rc;
+                       if (rc & MII_LAN83C185_ENERGYON)
+                               break;
+               }
 
                /* Re-enable EDPD */
                rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
@@ -191,7 +207,7 @@ static struct phy_driver smsc_phy_driver[] = {
 
        /* basic functions */
        .config_aneg    = genphy_config_aneg,
-       .read_status    = genphy_read_status,
+       .read_status    = lan87xx_read_status,
        .config_init    = smsc_phy_config_init,
        .soft_reset     = smsc_phy_reset,