Merge branch 'dsa-mv88e6xxx-lockdep'

Andrew Lunn says:

====================
mv88e6xxx: Avoid false positive Lockdep splats

When acquiring the GPIO interrupt line for the switch, it is possible
to trigger lockdep splats. These are false positives, the mutex is in
a different IRQ descriptor. But fix it anyway, since it could mask
real locking issues.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -442,16 +442,26 @@ static int mv88e6xxx_g1_irq_setup_common(struct mv88e6xxx_chip *chip)
 
 static int mv88e6xxx_g1_irq_setup(struct mv88e6xxx_chip *chip)
 {
+	static struct lock_class_key lock_key;
+	static struct lock_class_key request_key;
 	int err;
 
 	err = mv88e6xxx_g1_irq_setup_common(chip);
 	if (err)
 		return err;
 
+	/* These lock classes tells lockdep that global 1 irqs are in
+	 * a different category than their parent GPIO, so it won't
+	 * report false recursion.
+	 */
+	irq_set_lockdep_class(chip->irq, &lock_key, &request_key);
+
+	mutex_unlock(&chip->reg_lock);
 	err = request_threaded_irq(chip->irq, NULL,
 				   mv88e6xxx_g1_irq_thread_fn,
 				   IRQF_ONESHOT | IRQF_SHARED,
 				   dev_name(chip->dev), chip);
+	mutex_lock(&chip->reg_lock);
 	if (err)
 		mv88e6xxx_g1_irq_free_common(chip);