[PATCH net V3 2/3] net: lan743x: Support WOL at both the PHY and MAC appropriately

[Raju Lakkaraju <Raju.Lakkaraju@microchip.com>]

Prevent options not supported by the PHY from being requested to it by the MAC
Whenever a WOL option is supported by both, the PHY is given priority
since that usually leads to better power savings

Fixes: e9e13b6adc338 ("lan743x: fix for potential NULL pointer dereference with bare card")
Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com>
---
Change List:
------------
V2 -> V3:
  - Remove the "phy does not support WOL" debug message which is not required
  - Remove WAKE_PHY support option from Ethernet MAC (LAN743x/PCI11x1x) driver
  - Add "phy_wol_supported" and "phy_wolopts" variables to hold PHY's WOL config
V1 -> V2:
  - Repost - No change
V0 -> V1:
  - Change the "phy does not support WOL" print from netif_info() to
    netif_dbg()

 .../net/ethernet/microchip/lan743x_ethtool.c  | 44 +++++++++++++++++--
 drivers/net/ethernet/microchip/lan743x_main.c | 16 +++++--
 drivers/net/ethernet/microchip/lan743x_main.h |  4 ++
 3 files changed, 56 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan743x_ethtool.c b/drivers/net/ethernet/microchip/lan743x_ethtool.c
index d0f4ff4ee075..0d1740d64676 100644
--- a/drivers/net/ethernet/microchip/lan743x_ethtool.c
+++ b/drivers/net/ethernet/microchip/lan743x_ethtool.c
@@ -1127,8 +1127,12 @@ static void lan743x_ethtool_get_wol(struct net_device *netdev,
 	if (netdev->phydev)
 		phy_ethtool_get_wol(netdev->phydev, wol);
 
-	wol->supported |= WAKE_BCAST | WAKE_UCAST | WAKE_MCAST |
-		WAKE_MAGIC | WAKE_PHY | WAKE_ARP;
+	if (wol->supported != adapter->phy_wol_supported)
+		netif_warn(adapter, drv, adapter->netdev,
+			   "PHY changed its supported WOL! old=%x, new=%x\n",
+			   adapter->phy_wol_supported, wol->supported);
+
+	wol->supported |= MAC_SUPPORTED_WAKES;
 
 	if (adapter->is_pci11x1x)
 		wol->supported |= WAKE_MAGICSECURE;
@@ -1143,7 +1147,39 @@ static int lan743x_ethtool_set_wol(struct net_device *netdev,
 {
 	struct lan743x_adapter *adapter = netdev_priv(netdev);
 
+	/* WAKE_MAGICSEGURE is a modifier of and only valid together with
+	 * WAKE_MAGIC
+	 */
+	if ((wol->wolopts & WAKE_MAGICSECURE) && !(wol->wolopts & WAKE_MAGIC))
+		return -EINVAL;
+
+	if (netdev->phydev) {
+		struct ethtool_wolinfo phy_wol;
+		int ret;
+
+		phy_wol.wolopts = wol->wolopts & adapter->phy_wol_supported;
+
+		/* If WAKE_MAGICSECURE was requested, filter out WAKE_MAGIC
+		 * for PHYs that do not support WAKE_MAGICSECURE
+		 */
+		if (wol->wolopts & WAKE_MAGICSECURE &&
+		    !(adapter->phy_wol_supported & WAKE_MAGICSECURE))
+			phy_wol.wolopts &= ~WAKE_MAGIC;
+
+		ret = phy_ethtool_set_wol(netdev->phydev, &phy_wol);
+		if (ret && (ret != -EOPNOTSUPP))
+			return ret;
+
+		if (ret == -EOPNOTSUPP)
+			adapter->phy_wolopts = 0;
+		else
+			adapter->phy_wolopts = phy_wol.wolopts;
+	} else {
+		adapter->phy_wolopts = 0;
+	}
+
 	adapter->wolopts = 0;
+	wol->wolopts &= ~adapter->phy_wolopts;
 	if (wol->wolopts & WAKE_UCAST)
 		adapter->wolopts |= WAKE_UCAST;
 	if (wol->wolopts & WAKE_MCAST)
@@ -1164,10 +1200,10 @@ static int lan743x_ethtool_set_wol(struct net_device *netdev,
 		memset(adapter->sopass, 0, sizeof(u8) * SOPASS_MAX);
 	}
 
+	wol->wolopts = adapter->wolopts | adapter->phy_wolopts;
 	device_set_wakeup_enable(&adapter->pdev->dev, (bool)wol->wolopts);
 
-	return netdev->phydev ? phy_ethtool_set_wol(netdev->phydev, wol)
-			: -ENETDOWN;
+	return 0;
 }
 #endif /* CONFIG_PM */
 
diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index 6a40b961fafb..b6810840bc61 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -3118,6 +3118,15 @@ static int lan743x_netdev_open(struct net_device *netdev)
 		if (ret)
 			goto close_tx;
 	}
+
+	if (adapter->netdev->phydev) {
+		struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
+
+		phy_ethtool_get_wol(netdev->phydev, &wol);
+		adapter->phy_wol_supported = wol.supported;
+		adapter->phy_wolopts = wol.wolopts;
+	}
+
 	return 0;
 
 close_tx:
@@ -3587,10 +3596,9 @@ static void lan743x_pm_set_wol(struct lan743x_adapter *adapter)
 
 	pmtctl |= PMT_CTL_ETH_PHY_D3_COLD_OVR_ | PMT_CTL_ETH_PHY_D3_OVR_;
 
-	if (adapter->wolopts & WAKE_PHY) {
-		pmtctl |= PMT_CTL_ETH_PHY_EDPD_PLL_CTL_;
+	if (adapter->phy_wolopts)
 		pmtctl |= PMT_CTL_ETH_PHY_WAKE_EN_;
-	}
+
 	if (adapter->wolopts & WAKE_MAGIC) {
 		wucsr |= MAC_WUCSR_MPEN_;
 		macrx |= MAC_RX_RXEN_;
@@ -3686,7 +3694,7 @@ static int lan743x_pm_suspend(struct device *dev)
 	lan743x_csr_write(adapter, MAC_WUCSR2, 0);
 	lan743x_csr_write(adapter, MAC_WK_SRC, 0xFFFFFFFF);
 
-	if (adapter->wolopts)
+	if (adapter->wolopts || adapter->phy_wolopts)
 		lan743x_pm_set_wol(adapter);
 
 	if (adapter->is_pci11x1x) {
diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index fac0f33d10b2..3b2585a384e2 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -1042,6 +1042,8 @@ enum lan743x_sgmii_lsd {
 	LINK_2500_SLAVE
 };
 
+#define MAC_SUPPORTED_WAKES  (WAKE_BCAST | WAKE_UCAST | WAKE_MCAST | \
+			      WAKE_MAGIC | WAKE_ARP)
 struct lan743x_adapter {
 	struct net_device       *netdev;
 	struct mii_bus		*mdiobus;
@@ -1049,6 +1051,8 @@ struct lan743x_adapter {
 #ifdef CONFIG_PM
 	u32			wolopts;
 	u8			sopass[SOPASS_MAX];
+	u32			phy_wolopts;
+	u32			phy_wol_supported;
 #endif
 	struct pci_dev		*pdev;
 	struct lan743x_csr      csr;
-- 
2.34.1