phy: micrel.c: Enable ksz9031 energy-detect power-down mode
Set bit 0 in register 1C.23 to enable the EDPD feature of the
KSZ9031 PHY. This reduces power consumption when the link is
down.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 885ac9c..081df68 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -439,6 +439,10 @@
#define MII_KSZ9031RN_TX_DATA_PAD_SKEW 6
#define MII_KSZ9031RN_CLK_PAD_SKEW 8
+/* MMD Address 0x1C */
+#define MII_KSZ9031RN_EDPD 0x23
+#define MII_KSZ9031RN_EDPD_ENABLE BIT(0)
+
static int ksz9031_extended_write(struct phy_device *phydev,
u8 mode, u32 dev_addr, u32 regnum, u16 val)
{
@@ -510,6 +514,18 @@
return genphy_restart_aneg(phydev);
}
+/* Enable energy-detect power-down mode */
+static int ksz9031_enable_edpd(struct phy_device *phydev)
+{
+ int reg;
+
+ reg = ksz9031_extended_read(phydev, OP_DATA, 0x1C, MII_KSZ9031RN_EDPD);
+ if (reg < 0)
+ return reg;
+ return ksz9031_extended_write(phydev, OP_DATA, 0x1C, MII_KSZ9031RN_EDPD,
+ reg | MII_KSZ9031RN_EDPD_ENABLE);
+}
+
static int ksz9031_config_init(struct phy_device *phydev)
{
const struct device *dev = &phydev->mdio.dev;
@@ -525,6 +541,11 @@
};
static const char *control_skews[2] = {"txen-skew-ps", "rxdv-skew-ps"};
const struct device *dev_walker;
+ int result;
+
+ result = ksz9031_enable_edpd(phydev);
+ if (result < 0)
+ return result;
/* The Micrel driver has a deprecated option to place phy OF
* properties in the MAC node. Walk up the tree of devices to