net: pcs: xpcs: fix incorrect steps on disable EEE

When Energy-Efficient Ethernet(EEE) is disable from the MAC side,
we need to clear the DW_VR_MII_EEE_TRN_LPI bit of DW_VR_MII_EEE_MCTRL1
register.

Fixes: 7617af3d ("net: pcs: Introducing support for DWC xpcs Energy Efficient Ethernet")
Cc: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
Signed-off-by: Wong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/pcs/pcs-xpcs.c

@@ -666,6 +666,10 @@ int xpcs_config_eee(struct dw_xpcs *xpcs, int mult_fact_100ns, int enable)
 {
 	int ret;
 
+	ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL0);
+	if (ret < 0)
+		return ret;
+
 	if (enable) {
 	/* Enable EEE */
 		ret = DW_VR_MII_EEE_LTX_EN | DW_VR_MII_EEE_LRX_EN |
@@ -673,9 +677,6 @@ int xpcs_config_eee(struct dw_xpcs *xpcs, int mult_fact_100ns, int enable)
 		      DW_VR_MII_EEE_TX_EN_CTRL | DW_VR_MII_EEE_RX_EN_CTRL |
 		      mult_fact_100ns << DW_VR_MII_EEE_MULT_FACT_100NS_SHIFT;
 	} else {
-		ret = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL0);
-		if (ret < 0)
-			return ret;
 		ret &= ~(DW_VR_MII_EEE_LTX_EN | DW_VR_MII_EEE_LRX_EN |
 		       DW_VR_MII_EEE_TX_QUIET_EN | DW_VR_MII_EEE_RX_QUIET_EN |
 		       DW_VR_MII_EEE_TX_EN_CTRL | DW_VR_MII_EEE_RX_EN_CTRL |
@@ -690,7 +691,11 @@ int xpcs_config_eee(struct dw_xpcs *xpcs, int mult_fact_100ns, int enable)
 	if (ret < 0)
 		return ret;
 
+	if (enable)
 		ret |= DW_VR_MII_EEE_TRN_LPI;
+	else
+		ret &= ~DW_VR_MII_EEE_TRN_LPI;
+
 	return xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_EEE_MCTRL1, ret);
 }
 EXPORT_SYMBOL_GPL(xpcs_config_eee);