net: phy: broadcom: add bcm54xx_auxctl_read

Add a helper function to read the AUXCTL register for the BCM54xx.  This
mirrors the bcm54xx_auxctl_write function already present in the code.

Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 583ef8a..3a64b3d 100644 (file)
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -30,6 +30,16 @@ MODULE_DESCRIPTION("Broadcom PHY driver");
 MODULE_AUTHOR("Maciej W. Rozycki");
 MODULE_LICENSE("GPL");
 
+static int bcm54xx_auxctl_read(struct phy_device *phydev, u16 regnum)
+{
+       /* The register must be written to both the Shadow Register Select and
+        * the Shadow Read Register Selector
+        */
+       phy_write(phydev, MII_BCM54XX_AUX_CTL, regnum |
+                 regnum << MII_BCM54XX_AUXCTL_SHDWSEL_READ_SHIFT);
+       return phy_read(phydev, MII_BCM54XX_AUX_CTL);
+}
+
 static int bcm54xx_auxctl_write(struct phy_device *phydev, u16 regnum, u16 val)
 {
        return phy_write(phydev, MII_BCM54XX_AUX_CTL, regnum | val);

diff --git a/include/linux/brcmphy.h b/include/linux/brcmphy.h
index 60def78..0ed6691 100644 (file)
--- a/include/linux/brcmphy.h
+++ b/include/linux/brcmphy.h
@@ -110,6 +110,7 @@
 #define MII_BCM54XX_AUXCTL_MISC_FORCE_AMDIX    0x0200
 #define MII_BCM54XX_AUXCTL_MISC_RDSEL_MISC     0x7000
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MISC        0x0007
+#define MII_BCM54XX_AUXCTL_SHDWSEL_READ_SHIFT  12
 
 #define MII_BCM54XX_AUXCTL_SHDWSEL_MASK        0x0007