linux-kernel - [PATCH net-next v3 1/3] net: phy: Allow drivers to always call into ->suspend()

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Message-Id: <20230511172110.2243275-2-f.fainelli@gmail.com>
Date:   Thu, 11 May 2023 10:21:08 -0700
From:   Florian Fainelli <f.fainelli@...il.com>
To:     netdev@...r.kernel.org
Cc:     Florian Fainelli <f.fainelli@...il.com>,
        Simon Horman <simon.horman@...igine.com>,
        Andrew Lunn <andrew@...n.ch>, Doug Berger <opendmb@...il.com>,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@...adcom.com>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Heiner Kallweit <hkallweit1@...il.com>,
        Russell King <linux@...linux.org.uk>,
        Marek Behún <kabel@...nel.org>,
        Peter Geis <pgwipeout@...il.com>,
        Frank <Frank.Sae@...or-comm.com>,
        linux-kernel@...r.kernel.org (open list)
Subject: [PATCH net-next v3 1/3] net: phy: Allow drivers to always call into ->suspend()

A few PHY drivers are currently attempting to not suspend the PHY when
Wake-on-LAN is enabled, however that code is not currently executing at
all due to an early check in phy_suspend().

This prevents PHY drivers from making an appropriate decisions and put
the hardware into a low power state if desired.

In order to allow the PHY drivers to opt into getting their ->suspend
routine to be called, add a PHY_ALWAYS_CALL_SUSPEND bit which can be
set. A boolean that tracks whether the PHY or the attached MAC has
Wake-on-LAN enabled is also provided for convenience.

If phydev::wol_enabled then the PHY shall not prevent its own
Wake-on-LAN detection logic from working and shall not prevent the
Ethernet MAC from receiving packets for matching.

Reviewed-by: Simon Horman <simon.horman@...igine.com>
Reviewed-by: Andrew Lunn <andrew@...n.ch>
Signed-off-by: Florian Fainelli <f.fainelli@...il.com>
---
 drivers/net/phy/phy_device.c | 5 +++--
 include/linux/phy.h          | 4 ++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 17d0d0555a79..8852b0c53114 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1860,9 +1860,10 @@ int phy_suspend(struct phy_device *phydev)
 	if (phydev->suspended)
 		return 0;
 
-	/* If the device has WOL enabled, we cannot suspend the PHY */
 	phy_ethtool_get_wol(phydev, &wol);
-	if (wol.wolopts || (netdev && netdev->wol_enabled))
+	phydev->wol_enabled = wol.wolopts || (netdev && netdev->wol_enabled);
+	/* If the device has WOL enabled, we cannot suspend the PHY */
+	if (phydev->wol_enabled && !(phydrv->flags & PHY_ALWAYS_CALL_SUSPEND))
 		return -EBUSY;
 
 	if (!phydrv || !phydrv->suspend)
diff --git a/include/linux/phy.h b/include/linux/phy.h
index c5a0dc829714..e0df8b3c2bdb 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -86,6 +86,7 @@ extern const int phy_10gbit_features_array[1];
 #define PHY_IS_INTERNAL		0x00000001
 #define PHY_RST_AFTER_CLK_EN	0x00000002
 #define PHY_POLL_CABLE_TEST	0x00000004
+#define PHY_ALWAYS_CALL_SUSPEND	0x00000008
 #define MDIO_DEVICE_IS_PHY	0x80000000
 
 /**
@@ -548,6 +549,8 @@ struct macsec_ops;
  * @downshifted_rate: Set true if link speed has been downshifted.
  * @is_on_sfp_module: Set true if PHY is located on an SFP module.
  * @mac_managed_pm: Set true if MAC driver takes of suspending/resuming PHY
+ * @wol_enabled: Set to true if the PHY or the attached MAC have Wake-on-LAN
+ * 		 enabled.
  * @state: State of the PHY for management purposes
  * @dev_flags: Device-specific flags used by the PHY driver.
  *
@@ -644,6 +647,7 @@ struct phy_device {
 	unsigned downshifted_rate:1;
 	unsigned is_on_sfp_module:1;
 	unsigned mac_managed_pm:1;
+	unsigned wol_enabled:1;
 
 	unsigned autoneg:1;
 	/* The most recently read link state */
-- 
2.34.1