[PATCH] x86/ioapic: add IO-APIC irq_chip retrigger hook

[Ruslan Ruslichenko <rruslich@cisco.com>]

After commit d32932d02e18  ("x86/irq: Convert IOAPIC to use hierarchical
irqdomain interfaces") IO-APIC is switched to hierarchical irqdomain
implementation. Also this patch removed irq_retrigger hook for IO-APIC
chip which seem to be wrong. Without this hook some edge-triggered irq's
might be lost, since kernel uses it to retrigger edge irq's triggered
while they are being handled or disabled by driver
(see "Delayed_interrupt_disable" section at "Generic-IRQ-Guide"
of kernel docbook).

Thus adding this hook same way as it was done for MSI domain.

Signed-off-by: Ruslan Ruslichenko <rruslich@cisco.com>
---
 arch/x86/kernel/apic/io_apic.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 945e512..1e35dd0 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1875,6 +1875,7 @@ static int ioapic_set_affinity(struct irq_data *irq_data,
 	.irq_ack		= irq_chip_ack_parent,
 	.irq_eoi		= ioapic_ack_level,
 	.irq_set_affinity	= ioapic_set_affinity,
+	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.flags			= IRQCHIP_SKIP_SET_WAKE,
 };
 
@@ -1886,6 +1887,7 @@ static int ioapic_set_affinity(struct irq_data *irq_data,
 	.irq_ack		= irq_chip_ack_parent,
 	.irq_eoi		= ioapic_ir_ack_level,
 	.irq_set_affinity	= ioapic_set_affinity,
+	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.flags			= IRQCHIP_SKIP_SET_WAKE,
 };
 
-- 
1.9.1