genirq: Walk the irq_data hierarchy when resending an interrupt

On resending an interrupt, we only check the outermost irqchip for
a irq_retrigger callback. However, this callback could be implemented
at an inner level. Use irq_chip_retrigger_hierarchy() in this case.
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

kernel/irq/resend.c

@@ -86,6 +86,18 @@ static int irq_sw_resend(struct irq_desc *desc)
 }
 #endif
 
+static int try_retrigger(struct irq_desc *desc)
+{
+	if (desc->irq_data.chip->irq_retrigger)
+		return desc->irq_data.chip->irq_retrigger(&desc->irq_data);
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+	return irq_chip_retrigger_hierarchy(&desc->irq_data);
+#else
+	return 0;
+#endif
+}
+
 /*
  * IRQ resend
  *
@@ -113,8 +125,7 @@ int check_irq_resend(struct irq_desc *desc, bool inject)
 
 	desc->istate &= ~IRQS_PENDING;
 
-	if (!desc->irq_data.chip->irq_retrigger ||
-	    !desc->irq_data.chip->irq_retrigger(&desc->irq_data))
+	if (!try_retrigger(desc))
 		err = irq_sw_resend(desc);
 
 	/* If the retrigger was successfull, mark it with the REPLAY bit */