[PATCH net-next] net: phy: broadcom: Register dummy IRQ handler

[Florian Fainelli]

From: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>

In order to have our interrupt descriptor fully setup, and in particular
the action, ensure that we register a full fledged interrupt handler.
This is in particular necessary for the kernel to properly manage early
wake-up scenarios and arm the wake-up interrupt, otherwise there would
be risks of missing the interrupt and leaving it in a state where it
would not be handled correctly at all, including for wake-up purposes.

Fixes: 8baddaa9d4ba ("net: phy: broadcom: Add support for Wake-on-LAN")
Suggested-by: Doug Berger <doug.berger@xxxxxxxxxxxx>
Signed-off-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
---
 drivers/net/phy/bcm-phy-lib.c | 6 ++++++
 drivers/net/phy/bcm-phy-lib.h | 2 ++
 drivers/net/phy/broadcom.c    | 9 ++++++++-
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c
index 27c57f6ab211..5603d0a9ce96 100644
--- a/drivers/net/phy/bcm-phy-lib.c
+++ b/drivers/net/phy/bcm-phy-lib.c
@@ -1028,6 +1028,12 @@ void bcm_phy_get_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
 }
 EXPORT_SYMBOL_GPL(bcm_phy_get_wol);
 
+irqreturn_t bcm_phy_wol_isr(int irq, void *dev_id)
+{
+	return IRQ_HANDLED;
+}
+EXPORT_SYMBOL_GPL(bcm_phy_wol_isr);
+
 MODULE_DESCRIPTION("Broadcom PHY Library");
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Broadcom Corporation");
diff --git a/drivers/net/phy/bcm-phy-lib.h b/drivers/net/phy/bcm-phy-lib.h
index c6fed43ec913..2f30ce0cab0e 100644
--- a/drivers/net/phy/bcm-phy-lib.h
+++ b/drivers/net/phy/bcm-phy-lib.h
@@ -8,6 +8,7 @@
 
 #include <linux/brcmphy.h>
 #include <linux/phy.h>
+#include <linux/interrupt.h>
 
 struct ethtool_wolinfo;
 
@@ -115,5 +116,6 @@ static inline void bcm_ptp_stop(struct bcm_ptp_private *priv)
 
 int bcm_phy_set_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol);
 void bcm_phy_get_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol);
+irqreturn_t bcm_phy_wol_isr(int irq, void *dev_id);
 
 #endif /* _LINUX_BCM_PHY_LIB_H */
diff --git a/drivers/net/phy/broadcom.c b/drivers/net/phy/broadcom.c
index 418e6bc0e998..822c8b01dc53 100644
--- a/drivers/net/phy/broadcom.c
+++ b/drivers/net/phy/broadcom.c
@@ -927,7 +927,14 @@ static int bcm54xx_phy_probe(struct phy_device *phydev)
 
 	if (!IS_ERR(wakeup_gpio)) {
 		priv->wake_irq = gpiod_to_irq(wakeup_gpio);
-		ret = irq_set_irq_type(priv->wake_irq, IRQ_TYPE_LEVEL_LOW);
+
+		/* Dummy interrupt handler which is not enabled but is provided
+		 * in order for the interrupt descriptor to be fully set-up.
+		 */
+		ret = devm_request_irq(&phydev->mdio.dev, priv->wake_irq,
+				       bcm_phy_wol_isr,
+				       IRQF_TRIGGER_LOW | IRQF_NO_AUTOEN,
+				       dev_name(&phydev->mdio.dev), phydev);
 		if (ret)
 			return ret;
 	}
-- 
2.34.1

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