net: phy: improve phy_driver callback handle_interrupt

did_interrupt() clears the interrupt, therefore handle_interrupt() can
not check which event triggered the interrupt. To overcome this
constraint and allow more flexibility for customer interrupt handlers,
let's decouple handle_interrupt() from parts of the phylib interrupt
handling. Custom interrupt handlers now have to implement the
did_interrupt() functionality in handle_interrupt() if needed.

Fortunately we have just one custom interrupt handler so far (in the
mscc PHY driver), convert it to the changed API.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/mscc/mscc_main.c

@@ -1429,11 +1429,18 @@ static int vsc8584_config_init(struct phy_device *phydev)
 	return ret;
 }
 
-static int vsc8584_handle_interrupt(struct phy_device *phydev)
+static irqreturn_t vsc8584_handle_interrupt(struct phy_device *phydev)
 {
+	int irq_status;
+
+	irq_status = phy_read(phydev, MII_VSC85XX_INT_STATUS);
+	if (irq_status < 0 || !(irq_status & MII_VSC85XX_INT_MASK_MASK))
+		return IRQ_NONE;
+
 	vsc8584_handle_macsec_interrupt(phydev);
 	phy_mac_interrupt(phydev);
-	return 0;
+
+	return IRQ_HANDLED;
 }
 
 static int vsc85xx_config_init(struct phy_device *phydev)

drivers/net/phy/phy.c

@@ -715,28 +715,26 @@ static int phy_disable_interrupts(struct phy_device *phydev)
 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 {
 	struct phy_device *phydev = phy_dat;
+	struct phy_driver *drv = phydev->drv;
 
-	if (phydev->drv->did_interrupt && !phydev->drv->did_interrupt(phydev))
+	if (drv->handle_interrupt)
+		return drv->handle_interrupt(phydev);
+
+	if (drv->did_interrupt && !drv->did_interrupt(phydev))
 		return IRQ_NONE;
 
-	if (phydev->drv->handle_interrupt) {
-		if (phydev->drv->handle_interrupt(phydev))
-			goto phy_err;
-	} else {
 	/* reschedule state queue work to run as soon as possible */
 	phy_trigger_machine(phydev);
-	}
 
 	/* did_interrupt() may have cleared the interrupt already */
-	if (!phydev->drv->did_interrupt && phy_clear_interrupt(phydev))
+	if (!drv->did_interrupt && phy_clear_interrupt(phydev)) {
-		goto phy_err;
-	return IRQ_HANDLED;
-
-phy_err:
 		phy_error(phydev);
 		return IRQ_NONE;
 	}
 
+	return IRQ_HANDLED;
+}
+
 /**
  * phy_enable_interrupts - Enable the interrupts from the PHY side
  * @phydev: target phy_device struct

include/linux/phy.h

@@ -23,6 +23,7 @@
 #include <linux/workqueue.h>
 #include <linux/mod_devicetable.h>
 #include <linux/u64_stats_sync.h>
+#include <linux/irqreturn.h>
 
 #include <linux/atomic.h>
 
@@ -568,7 +569,7 @@ struct phy_driver {
 	int (*did_interrupt)(struct phy_device *phydev);
 
 	/* Override default interrupt handling */
-	int (*handle_interrupt)(struct phy_device *phydev);
+	irqreturn_t (*handle_interrupt)(struct phy_device *phydev);
 
 	/* Clears up any memory if needed */
 	void (*remove)(struct phy_device *phydev);