[PATCH] net: phy: fix may not suspend when phy has WoL

[WangYuli]

From: Wentao Guan <guanwentao@xxxxxxxxxxxxx>

When system suspends and mdio_bus_phy goes to suspend, if the phy
enabled wol, phy_suspend will returned -EBUSY, and break system
suspend.

Commit 93f41e67dc8f ("net: phy: fix WoL handling when suspending
the PHY") fixes the case when netdev->wol_enabled=1, but some case,
netdev->wol_enabled=0 and phydev set wol_enabled enabled, so check
phydev->wol_enabled.

This case happens when using some out of tree ethernet drivers or
phy drivers.

Log:
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: dpm_run_callback(): mdio_bus_phy_suspend+0x0/0x10c returns -16
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: failed to suspend: error -16
PM: Some devices failed to suspend, or early wake event detected
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: dpm_run_callback(): mdio_bus_phy_suspend+0x0/0x10c returns -16
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: failed to suspend: error -16
PM: Some devices failed to suspend, or early wake event detected
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: dpm_run_callback(): mdio_bus_phy_suspend+0x0/0x10c returns -16
YT8531S Gigabit Ethernet phytmac_mii_bus-PHYT0046:00:07: PM: failed to freeze: error -16

Link: https://lore.kernel.org/all/20240827092446.7948-1-guanwentao@xxxxxxxxxxxxx/
Fixes: 481b5d938b4a ("net: phy: provide phy_resume/phy_suspend helpers")
Signed-off-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
Signed-off-by: WangYuli <wangyuli@xxxxxxxxxxxxx>
---
 drivers/net/phy/phy_device.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index bc24c9f2786b..12af590bfd99 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -315,6 +315,19 @@ static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 	if (netdev->ethtool->wol_enabled)
 		return false;
 
+	/* Ethernet and phy device wol state may not same, netdev->wol_enabled
+	 * disabled, and phydev set wol_enabled enabled, so netdev->wol_enabled
+	 * is not enough.
+	 * Check phydev->wol_enabled.
+	 */
+	struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
+
+	phy_ethtool_get_wol(phydev, &wol);
+	if (wol.wolopts) {
+		phydev_warn(phydev, "Phy and mac wol are not compatible\n");
+		return false;
+	}
+
 	/* As long as not all affected network drivers support the
 	 * wol_enabled flag, let's check for hints that WoL is enabled.
 	 * Don't suspend PHY if the attached netdev parent may wake up.
-- 
2.45.2