net: phy: nxp-tja11xx: implement generic .handle_interrupt() callback

In an attempt to actually support shared IRQs in phylib, we now move the
responsibility of triggering the phylib state machine or just returning
IRQ_NONE, based on the IRQ status register, to the PHY driver. Having
3 different IRQ handling callbacks (.handle_interrupt(),
.did_interrupt() and .ack_interrupt() ) is confusing so let the PHY
driver implement directly an IRQ handler like any other device driver.
Make this driver follow the new convention.

Cc: Marek Vasut <[e-mail]>
Cc: Oleksij Rempel <[e-mail]>
Signed-off-by: Ioana Ciornei <[e-mail]>
Signed-off-by: Jakub Kicinski <[e-mail]>

drivers/net/phy/nxp-tja11xx.c

···
 #define MII_CFG2_SLEEP_REQUEST_TO_16MS	0x3
 
 #define MII_INTSRC			21
+#define MII_INTSRC_LINK_FAIL		BIT(10)
+#define MII_INTSRC_LINK_UP		BIT(9)
+#define MII_INTSRC_MASK			(MII_INTSRC_LINK_FAIL | MII_INTSRC_LINK_UP)
 #define MII_INTSRC_TEMP_ERR		BIT(1)
 #define MII_INTSRC_UV_ERR		BIT(3)
 
···
 	return phy_write(phydev, MII_INTEN, value);
 }
 
+static irqreturn_t tja11xx_handle_interrupt(struct phy_device *phydev)
+{
+	int irq_status;
+
+	irq_status = phy_read(phydev, MII_INTSRC);
+	if (irq_status < 0) {
+		phy_error(phydev);
+		return IRQ_NONE;
+	}
+
+	if (!(irq_status & MII_INTSRC_MASK))
+		return IRQ_NONE;
+
+	phy_trigger_machine(phydev);
+
+	return IRQ_HANDLED;
+}
+
 static int tja11xx_cable_test_start(struct phy_device *phydev)
 {
 	int ret;
···
 		.get_stats	= tja11xx_get_stats,
 		.ack_interrupt	= tja11xx_ack_interrupt,
 		.config_intr	= tja11xx_config_intr,
+		.handle_interrupt = tja11xx_handle_interrupt,
 		.cable_test_start = tja11xx_cable_test_start,
 		.cable_test_get_status = tja11xx_cable_test_get_status,
 	}, {
···
 		.get_stats	= tja11xx_get_stats,
 		.ack_interrupt	= tja11xx_ack_interrupt,
 		.config_intr	= tja11xx_config_intr,
+		.handle_interrupt = tja11xx_handle_interrupt,
 		.cable_test_start = tja11xx_cable_test_start,
 		.cable_test_get_status = tja11xx_cable_test_get_status,
 	}