genirq: Define irq_ack() and irq_eoi() helpers

The newly-added IRQCHIP_AUTOMASKS_FLOW flag requires some additional
bookkeeping around chip->{irq_ack, irq_eoi}() calls. Define wrappers around
those chip callbacks to drive the IRQD_IRQ_FLOW_MASKED state of an IRQ when
the chip has the IRQCHIP_AUTOMASKS_FLOW flag.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>

kernel/irq/chip.c

@@ -408,6 +408,22 @@ void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
 	cpumask_clear_cpu(cpu, desc->percpu_enabled);
 }
 
+void ack_irq(struct irq_desc *desc)
+{
+	desc->irq_data.chip->irq_ack(&desc->irq_data);
+
+	if (desc->irq_data.chip->flags & IRQCHIP_AUTOMASKS_FLOW)
+		irq_state_set_flow_masked(desc);
+}
+
+void eoi_irq(struct irq_desc *desc)
+{
+	desc->irq_data.chip->irq_eoi(&desc->irq_data);
+
+	if (desc->irq_data.chip->flags & IRQCHIP_AUTOMASKS_FLOW)
+		irq_state_clr_flow_masked(desc);
+}
+
 static inline void mask_ack_irq(struct irq_desc *desc)
 {
 	if (desc->irq_data.chip->irq_mask_ack) {

kernel/irq/internals.h

@@ -87,6 +87,8 @@ extern void irq_enable(struct irq_desc *desc);
 extern void irq_disable(struct irq_desc *desc);
 extern void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu);
 extern void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu);
+extern void irq_ack(struct irq_desc *desc);
+extern void irq_eoi(struct irq_desc *desc);
 extern void mask_irq(struct irq_desc *desc);
 extern void unmask_irq(struct irq_desc *desc);
 extern void unmask_threaded_irq(struct irq_desc *desc);