net: add phylink managed WoL and convert stmmac

Hi,

This series is implementing the thoughts of Andrew, Florian and myself to improve the quality of Wake-on-Lan (WoL) implementations.

This changes nothing for MAC drivers that do not wish to participate in this, but if they do, then they gain the benefit of phylink configuring WoL at the point closest to the media as possible.

We first need to solve the problem that the multitude of PHY drivers report their device supports WoL, but are not capable of waking the system. Correcting this is fundamental to choosing where WoL should be enabled - a mis-reported WoL support can render WoL completely ineffective.

The only PHY drivers which uses the driver model's wakeup support is drivers/net/phy/broadcom.c, and until recently, realtek. This means we have the opportunity for PHY drivers to be _correctly_ converted to use this method of signalling wake-up capability only when they can actually wake the system, and thus providing a way for phylink to know whether to use PHY-based WoL at all.

However, a PHY driver not implementing that logic doesn't become a blocker to MACs wanting to convert. In full, the logic is:

- phylink supports a flag, wol_phy_legacy, which forces phylink to use the PHY-based WoL even if the MDIO device is not marked as wake-up capable.

- when wol_phy_legacy is not set, we check whether the PHY MDIO device is wake-up capable. If it is, we offer the WoL request to the PHY.

- if neither wol_phy_legacy is set, or the PHY is not wake-up capable, we do not offer the WoL request to the PHY.

In both cases, after setting any PHY based WoL, we remove the options that the PHY now reports are enabled from the options mask, and offer these (if any) to the MAC. The mac will get a "mac_set_wol()" method call when any settings change.

Phylink mainatains the WoL state for the MAC, so there's no need for a "mac_get_wol()" method. There may be the need to set the initial state but this is not supported at present.

I've also added support for doing the PHY speed-up/speed-down at suspend/resume time depending on the WoL state, which takes another issue from the MAC authors.

Lastly, with phylink now having the full picture for WoL, the "mac_wol" argument for phylink_suspend() becomes redundant, and for MAC drivers that implement mac_set_wol(), the value passed becomes irrelevant.

Changes since RFC:
- patch 3: fix location of phylink_xxx_supports_wol() helpers
- patch 3: handle sopass for WAKE_MAGICSECURE only when the MAC is handling magic secure.

  drivers/net/ethernet/stmicro/stmmac/stmmac.h       | 11 +--
  .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c   | 31 +-------
  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  | 45 +++++++----
  .../net/ethernet/stmicro/stmmac/stmmac_platform.c  |  4 +-
  drivers/net/phy/phy_device.c                       | 14 +++-
  drivers/net/phy/phylink.c                          | 92 +++++++++++++++++++++-
  include/linux/phy.h                                | 21 +++++
  include/linux/phylink.h                            | 28 +++++++
  8 files changed, 182 insertions(+), 64 deletions(-)

Hi,

This series is implementing the thoughts of Andrew, Florian and myself to improve the quality of Wake-on-Lan (WoL) implementations.

This changes nothing for MAC drivers that do not wish to participate in this, but if they do, then they gain the benefit of phylink configuring WoL at the point closest to the media as possible.

We first need to solve the problem that the multitude of PHY drivers report their device supports WoL, but are not capable of waking the system. Correcting this is fundamental to choosing where WoL should be enabled - a mis-reported WoL support can render WoL completely ineffective.

The only PHY drivers which uses the driver model's wakeup support is drivers/net/phy/broadcom.c, and until recently, realtek. This means we have the opportunity for PHY drivers to be _correctly_ converted to use this method of signalling wake-up capability only when they can actually wake the system, and thus providing a way for phylink to know whether to use PHY-based WoL at all.

However, a PHY driver not implementing that logic doesn't become a blocker to MACs wanting to convert. In full, the logic is:

- phylink supports a flag, wol_phy_legacy, which forces phylink to use the PHY-based WoL even if the MDIO device is not marked as wake-up capable.

- when wol_phy_legacy is not set, we check whether the PHY MDIO device is wake-up capable. If it is, we offer the WoL request to the PHY.

- if neither wol_phy_legacy is set, or the PHY is not wake-up capable, we do not offer the WoL request to the PHY.

In both cases, after setting any PHY based WoL, we remove the options that the PHY now reports are enabled from the options mask, and offer these (if any) to the MAC. The mac will get a "mac_set_wol()" method call when any settings change.

Phylink mainatains the WoL state for the MAC, so there's no need for a "mac_get_wol()" method. There may be the need to set the initial state but this is not supported at present.

I've also added support for doing the PHY speed-up/speed-down at suspend/resume time depending on the WoL state, which takes another issue from the MAC authors.

Lastly, with phylink now having the full picture for WoL, the "mac_wol" argument for phylink_suspend() becomes redundant, and for MAC drivers that implement mac_set_wol(), the value passed becomes irrelevant.

Changes since RFC:
- patch 3: fix location of phylink_xxx_supports_wol() helpers
- patch 3: handle sopass for WAKE_MAGICSECURE only when the MAC is handling magic secure.

 drivers/net/ethernet/stmicro/stmmac/stmmac.h       | 11 +--
 .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c   | 31 +-------
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  | 45 +++++++----
 .../net/ethernet/stmicro/stmmac/stmmac_platform.c  |  4 +-
 drivers/net/phy/phy_device.c                       | 14 +++-
 drivers/net/phy/phylink.c                          | 92 +++++++++++++++++++++-
 include/linux/phy.h                                | 21 +++++
 include/linux/phylink.h                            | 28 +++++++
 8 files changed, 182 insertions(+), 64 deletions(-)

Signature · 2 lines

RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Add phy_can_wakeup() to report whether the PHY driver has marked the PHY device as being wake-up capable as far as the driver model is concerned.

Signed-off-by Russell King (Oracle) <[email protected]>

---
 include/linux/phy.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

include/linux/phy.h +12 -0

index 3c7634482356..3eeeaec52832 100644
@@ -1379,6 +1379,18 @@ static inline void phy_disable_eee_mode(struct phy_device *phydev, u32 link_mode
 	linkmode_clear_bit(link_mode, phydev->advertising_eee);
 }
 
+/**
+ * phy_can_wakeup() - indicate whether PHY has driver model wakeup capabilities
+ * @phydev: The phy_device struct
+ *
+ * Returns: true/false depending on the PHY driver's device_set_wakeup_capable()
+ * setting.
+ */
+static inline bool phy_can_wakeup(struct phy_device *phydev)
+{
+	return device_can_wakeup(&phydev->mdio.dev);
+}
+
 void phy_resolve_aneg_pause(struct phy_device *phydev);
 void phy_resolve_aneg_linkmode(struct phy_device *phydev);
 

Add phy_may_wakeup() which uses the driver model's device_may_wakeup() when the PHY driver has marked the device as wakeup capable in the driver model, otherwise use phy_drv_wol_enabled().

Replace the sites that used to call phy_drv_wol_enabled() with this as checking the driver model will be more efficient than checking the WoL state.

Export phy_may_wakeup() so that phylink can use it.

Signed-off-by Russell King (Oracle) <[email protected]>

---
 drivers/net/phy/phy_device.c | 14 ++++++++++++--
 include/linux/phy.h          |  9 +++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

drivers/net/phy/phy_device.c +12 -2

index 7a67c900e79a..b7feaf0cb1df 100644
@@ -251,6 +251,16 @@ static bool phy_drv_wol_enabled(struct phy_device *phydev)
 	return wol.wolopts != 0;
 }
 
+bool phy_may_wakeup(struct phy_device *phydev)
+{
+	/* If the PHY is using driver-model based wakeup, use that state. */
+	if (phy_can_wakeup(phydev))
+		return device_may_wakeup(&phydev->mdio.dev);
+
+	return phy_drv_wol_enabled(phydev);
+}
+EXPORT_SYMBOL_GPL(phy_may_wakeup);
+
 static void phy_link_change(struct phy_device *phydev, bool up)
 {
 	struct net_device *netdev = phydev->attached_dev;

@@ -302,7 +312,7 @@ static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 	/* If the PHY on the mido bus is not attached but has WOL enabled
 	 * we cannot suspend the PHY.
 	 */
-	if (!netdev && phy_drv_wol_enabled(phydev))
+	if (!netdev && phy_may_wakeup(phydev))
 		return false;
 
 	/* PHY not attached? May suspend if the PHY has not already been

@@ -1909,7 +1919,7 @@ int phy_suspend(struct phy_device *phydev)
 	if (phydev->suspended || !phydrv)
 		return 0;
 
-	phydev->wol_enabled = phy_drv_wol_enabled(phydev) ||
+	phydev->wol_enabled = phy_may_wakeup(phydev) ||
 			      (netdev && netdev->ethtool->wol_enabled);
 	/* If the device has WOL enabled, we cannot suspend the PHY */
 	if (phydev->wol_enabled && !(phydrv->flags & PHY_ALWAYS_CALL_SUSPEND))

include/linux/phy.h +0 -0

index 3eeeaec52832..801356da1fb2 100644

Add core phylink managed Wake-on-Lan support, which is enabled when the MAC driver fills in the new .mac_wol_set() method that this commit creates.

When this feature is disabled, phylink acts as it has in the past, merely passing the ethtool WoL calls to phylib whenever a PHY exists. No other new functionality provided by this commit is enabled.

When this feature is enabled, a more inteligent approach is used. Phylink will first pass WoL options to the PHY, read them back, and attempt to set any options that were not set at the PHY at the MAC.

Since we have PHY drivers that report they support WoL, and accept WoL configuration even though they aren't wired up to be capable of waking the system, we need a way to differentiate between PHYs that think they support WoL and those which actually do. As PHY drivers do not make use of the driver model's wake-up infrastructure, but could, we use this to determine whether PHY drivers can participate. This gives a path forward where, as MAC drivers are converted to this, it encourages PHY drivers to also be converted.

Phylink will also ignore the mac_wol argument to phylink_suspend() as it now knows the WoL state at the MAC.

MAC drivers are expected to record/configure the Wake-on-Lan state in their .mac_set_wol() method, and deal appropriately with it in their suspend/resume methods. The driver model provides assistance to set the IRQ wake support which may assist driver authors in achieving the necessary configuration.

Signed-off-by Russell King (Oracle) <[email protected]>

---
 drivers/net/phy/phylink.c | 80 +++++++++++++++++++++++++++++++++++++--
 include/linux/phylink.h   | 26 +++++++++++++
 2 files changed, 102 insertions(+), 4 deletions(-)

drivers/net/phy/phylink.c +45 -4

index 9d7799ea1c17..939438a6d6f5 100644
@@ -93,6 +93,9 @@ struct phylink {
 	u8 sfp_port;
 
 	struct eee_config eee_cfg;
+
+	u32 wolopts_mac;
+	u8 wol_sopass[SOPASS_MAX];
 };
 
 #define phylink_printk(level, pl, fmt, ...) \

@@ -2562,6 +2565,17 @@ void phylink_rx_clk_stop_unblock(struct phylink *pl)
 }
 EXPORT_SYMBOL_GPL(phylink_rx_clk_stop_unblock);
 
+static bool phylink_mac_supports_wol(struct phylink *pl)
+{
+	return !!pl->mac_ops->mac_wol_set;
+}
+
+static bool phylink_phy_supports_wol(struct phylink *pl,
+				     struct phy_device *phydev)
+{
+	return phydev && (pl->config->wol_phy_legacy || phy_can_wakeup(phydev));
+}
+
 /**
  * phylink_suspend() - handle a network device suspend event
  * @pl: a pointer to a &struct phylink returned from phylink_create()

@@ -2575,11 +2589,17 @@ EXPORT_SYMBOL_GPL(phylink_rx_clk_stop_unblock);
  *   can also bring down the link between the MAC and PHY.
  * - If Wake-on-Lan is active, but being handled by the MAC, the MAC
  *   still needs to receive packets, so we can not bring the link down.
+ *
+ * Note: when phylink managed Wake-on-Lan is in use, @mac_wol is ignored.
+ * (struct phylink_mac_ops.mac_set_wol populated.)
  */
 void phylink_suspend(struct phylink *pl, bool mac_wol)
 {
 	ASSERT_RTNL();
 
+	if (phylink_mac_supports_wol(pl))
+		mac_wol = !!pl->wolopts_mac;
+
 	if (mac_wol && (!pl->netdev || pl->netdev->ethtool->wol_enabled)) {
 		/* Wake-on-Lan enabled, MAC handling */
 		mutex_lock(&pl->state_mutex);

@@ -2689,8 +2709,24 @@ void phylink_ethtool_get_wol(struct phylink *pl, struct ethtool_wolinfo *wol)
 	wol->supported = 0;
 	wol->wolopts = 0;
 
-	if (pl->phydev)
-		phy_ethtool_get_wol(pl->phydev, wol);
+	if (phylink_mac_supports_wol(pl)) {
+		if (phylink_phy_supports_wol(pl, pl->phydev))
+			phy_ethtool_get_wol(pl->phydev, wol);
+
+		/* Where the MAC augments the WoL support, merge its support and
+		 * current configuration.
+		 */
+		if (~wol->wolopts & pl->wolopts_mac & WAKE_MAGICSECURE)
+			memcpy(wol->sopass, pl->wol_sopass,
+			       sizeof(wol->sopass));
+
+		wol->supported |= pl->config->wol_mac_support;
+		wol->wolopts |= pl->wolopts_mac;
+	} else {
+		/* Legacy */
+		if (pl->phydev)
+			phy_ethtool_get_wol(pl->phydev, wol);
+	}
 }
 EXPORT_SYMBOL_GPL(phylink_ethtool_get_wol);
 

@@ -2707,12 +2743,48 @@ EXPORT_SYMBOL_GPL(phylink_ethtool_get_wol);
  */
 int phylink_ethtool_set_wol(struct phylink *pl, struct ethtool_wolinfo *wol)
 {
+	struct ethtool_wolinfo w;
 	int ret = -EOPNOTSUPP;
+	bool changed;
+	u32 wolopts;
 
 	ASSERT_RTNL();
 
-	if (pl->phydev)
-		ret = phy_ethtool_set_wol(pl->phydev, wol);
+	if (phylink_mac_supports_wol(pl)) {
+		wolopts = wol->wolopts;
+
+		if (phylink_phy_supports_wol(pl, pl->phydev)) {

drivers/net/phy/phylink.c +21 -0

+		}
+
+		wolopts &= pl->config->wol_mac_support;
+		changed = pl->wolopts_mac != wolopts;
+		if (wolopts & WAKE_MAGICSECURE)
+			changed |= !!memcmp(wol->sopass, pl->wol_sopass,
+					    sizeof(wol->sopass));
+		memcpy(pl->wol_sopass, wol->sopass, sizeof(pl->wol_sopass));
+
+		if (changed) {
+			ret = pl->mac_ops->mac_wol_set(pl->config, wolopts,
+						       wol->sopass);
+			if (!ret)
+				pl->wolopts_mac = wolopts;
+		} else {
+			ret = 0;
+		}
+	} else {
+		if (pl->phydev)
+			ret = phy_ethtool_set_wol(pl->phydev, wol);
+	}
 
 	return ret;
 }

include/linux/phylink.h +19 -0

index 9af0411761d7..59cb58b29d1d 100644
@@ -156,6 +156,8 @@ enum phylink_op_type {
  * @lpi_capabilities: MAC speeds which can support LPI signalling
  * @lpi_timer_default: Default EEE LPI timer setting.
  * @eee_enabled_default: If set, EEE will be enabled by phylink at creation time
+ * @wol_phy_legacy: Use Wake-on-Lan with PHY even if phy_can_wakeup() is false
+ * @wol_mac_support: Bitmask of MAC supported %WAKE_* options
  */
 struct phylink_config {
 	struct device *dev;

@@ -173,6 +175,10 @@ struct phylink_config {
 	unsigned long lpi_capabilities;
 	u32 lpi_timer_default;
 	bool eee_enabled_default;
+
+	/* Wake-on-Lan support */
+	bool wol_phy_legacy;
+	u32 wol_mac_support;
 };
 
 void phylink_limit_mac_speed(struct phylink_config *config, u32 max_speed);

@@ -188,6 +194,7 @@ void phylink_limit_mac_speed(struct phylink_config *config, u32 max_speed);
  * @mac_link_up: allow the link to come up.
  * @mac_disable_tx_lpi: disable LPI.
  * @mac_enable_tx_lpi: enable and configure LPI.
+ * @mac_wol_set: configure Wake-on-Lan settings at the MAC.
  *
  * The individual methods are described more fully below.
  */

@@ -211,6 +218,9 @@ struct phylink_mac_ops {
 	void (*mac_disable_tx_lpi)(struct phylink_config *config);
 	int (*mac_enable_tx_lpi)(struct phylink_config *config, u32 timer,
 				 bool tx_clk_stop);
+
+	int (*mac_wol_set)(struct phylink_config *config, u32 wolopts,
+			   const u8 *sopass);
 };
 
 #if 0 /* For kernel-doc purposes only. */

@@ -440,6 +450,22 @@ void mac_disable_tx_lpi(struct phylink_config *config);
  */
 int mac_enable_tx_lpi(struct phylink_config *config, u32 timer,
 		      bool tx_clk_stop);
+
+/**
+ * mac_wol_set() - configure the Wake-on-Lan parameters
+ * @config: a pointer to a &struct phylink_config.
+ * @wolopts: Bitmask of %WAKE_* flags for enabled Wake-On-Lan modes.
+ * @sopass: SecureOn(tm) password; meaningful only for %WAKE_MAGICSECURE
+ *
+ * Enable the specified Wake-on-Lan options at the MAC. Options that the
+ * PHY can handle will have been removed from @wolopts.

Some drivers, e.g. stmmac, use the speed_up()/speed_down() APIs to gain additional power saving during Wake-on-LAN where the PHY is managing the state.

Add support to phylink for this, which can be enabled by the MAC driver. Only change the PHY speed if the PHY is configured for wake-up, but without any wake-up on the MAC side, as MAC side means changing the configuration once the negotiation has completed.

Signed-off-by Russell King (Oracle) <[email protected]>

---
 drivers/net/phy/phylink.c | 12 ++++++++++++
 include/linux/phylink.h   |  2 ++
 2 files changed, 14 insertions(+)

drivers/net/phy/phylink.c +6 -0

index 939438a6d6f5..26bd4b7619dd 100644
@@ -2576,6 +2576,12 @@ static bool phylink_phy_supports_wol(struct phylink *pl,
 	return phydev && (pl->config->wol_phy_legacy || phy_can_wakeup(phydev));
 }
 
+static bool phylink_phy_pm_speed_ctrl(struct phylink *pl)
+{
+	return pl->config->wol_phy_speed_ctrl && !pl->wolopts_mac &&
+	       pl->phydev && phy_may_wakeup(pl->phydev);
+}
+
 /**
  * phylink_suspend() - handle a network device suspend event
  * @pl: a pointer to a &struct phylink returned from phylink_create()

Hi Russell,

drivers/net/phy/phylink.c void phylink_suspend(struct phylink *pl, bool mac_wol) · line 2636

Quoted 3 lines

drivers/net/phy/phylink.c +3 -0

+
+	if (phylink_phy_pm_speed_ctrl(pl))
+		phy_speed_down(pl->phydev, false);

Should this rather be phylink_speed_down, to take into account the fact
that the PHY might be on SFP ? either here or directly in
phylink_phy_pm_speed_ctrl() above ?

Add phy_can_wakeup() to report whether the PHY driver has marked the PHY device as being wake-up capable as far as the driver model is concerned.

Signed-off-by Russell King (Oracle) <[email protected]>

Add phy_may_wakeup() which uses the driver model's device_may_wakeup() when the PHY driver has marked the device as wakeup capable in the driver model, otherwise use phy_drv_wol_enabled().

Replace the sites that used to call phy_drv_wol_enabled() with this as checking the driver model will be more efficient than checking the WoL state.

Export phy_may_wakeup() so that phylink can use it.

Signed-off-by Russell King (Oracle) <[email protected]>

Add core phylink managed Wake-on-Lan support, which is enabled when the MAC driver fills in the new .mac_wol_set() method that this commit creates.

When this feature is disabled, phylink acts as it has in the past, merely passing the ethtool WoL calls to phylib whenever a PHY exists. No other new functionality provided by this commit is enabled.

When this feature is enabled, a more inteligent approach is used. Phylink will first pass WoL options to the PHY, read them back, and attempt to set any options that were not set at the PHY at the MAC.

Since we have PHY drivers that report they support WoL, and accept WoL configuration even though they aren't wired up to be capable of waking the system, we need a way to differentiate between PHYs that think they support WoL and those which actually do. As PHY drivers do not make use of the driver model's wake-up infrastructure, but could, we use this to determine whether PHY drivers can participate. This gives a path forward where, as MAC drivers are converted to this, it encourages PHY drivers to also be converted.

Phylink will also ignore the mac_wol argument to phylink_suspend() as it now knows the WoL state at the MAC.

MAC drivers are expected to record/configure the Wake-on-Lan state in their .mac_set_wol() method, and deal appropriately with it in their suspend/resume methods. The driver model provides assistance to set the IRQ wake support which may assist driver authors in achieving the necessary configuration.

Signed-off-by Russell King (Oracle) <[email protected]>

Hi Russell,

That's not exactly what's happening, this suggest this is merely a wrapper around device_may_wakeup().

I don't think it's worth blocking the series though, but if you need to respin maybe this could be reworded.

Reviewed-by Maxime Chevallier <[email protected]>

Quoted 8 lines · Russell King (Oracle)

Add phy_may_wakeup() which uses the driver model's device_may_wakeup() when the PHY driver has marked the device as wakeup capable in the driver model, otherwise use phy_drv_wol_enabled().

Replace the sites that used to call phy_drv_wol_enabled() with this as checking the driver model will be more efficient than checking the WoL state.

Quoted 3 lines

Export phy_may_wakeup() so that phylink can use it.

Signed-off-by Russell King (Oracle) <[email protected]>

Reviewed-by Florian Fainelli <[email protected]>

Quoted 3 lines

int phylink_ethtool_set_wol(struct phylink *pl, struct ethtool_wolinfo *wol) {

drivers/net/phy/phylink.c +1 -0

+	struct ethtool_wolinfo w;

drivers/net/phy/phylink.c EXPORT_SYMBOL_GPL(phylink_ethtool_get_wol); · line 2766

Quoted 6 lines

drivers/net/phy/phylink.c +6 -0

+			phy_ethtool_get_wol(pl->phydev, &w);
+
+			/* Any Wake-on-Lan modes which the PHY is handling
+			 * should not be passed on to the MAC.
+			 */
+			wolopts &= ~w.wolopts;

When PHY drivers gets converted to the new model, we'll have to look at how the .get_wol() behave WRT how they fill-in their wolopts.

The Broadcom driver for example may not set w.wolopts to 0 :

https://elixir.bootlin.com/linux/v6.17.4/source/drivers/net/phy/broadcom.c#L1121

You'd probably end-up with garbage here then. But not blocking for your series.

Quoted 9 lines · Maxime Chevallier

Hi Russell,

That's not exactly what's happening, this suggest this is merely a wrapper around device_may_wakeup().

I don't think it's worth blocking the series though, but if you need to respin maybe this could be reworded.

Reviewed-by Maxime Chevallier <[email protected]>

I've updated the description as I think patch 4 needs a repost:

include/linux/phy.h +9 -0

+/**
+ * phy_may_wakeup() - indicate whether PHY has wakeup enabled
+ * @phydev: The phy_device struct
+ *
+ * Returns: true/false depending on the PHY driver's device_set_wakeup_enabled()
+ * setting if using the driver model, otherwise the legacy determination.
+ */
+bool phy_may_wakeup(struct phy_device *phydev);
+

Do you want me to still add your r-b?

Quoted 9 lines · Maxime Chevallier

Hi Russell,

That's not exactly what's happening, this suggest this is merely a wrapper around device_may_wakeup().

I don't think it's worth blocking the series though, but if you need to respin maybe this could be reworded.

Reviewed-by Maxime Chevallier <[email protected]>

I've updated the description as I think patch 4 needs a repost:

include/linux/phy.h +9 -0

+/**
+ * phy_may_wakeup() - indicate whether PHY has wakeup enabled
+ * @phydev: The phy_device struct
+ *
+ * Returns: true/false depending on the PHY driver's device_set_wakeup_enabled()
+ * setting if using the driver model, otherwise the legacy determination.
+ */
+bool phy_may_wakeup(struct phy_device *phydev);
+

Do you want me to still add your r-b?