[ARM] 3690/1: genirq: Introduce and make use of dummy irq chip

Patch from Thomas Gleixner

From: Thomas Gleixner <tglx@linutronix.de>

ARM has a couple of really dumb interrupt controllers.
Implement a generic one and fixup the ARM migration. ARM reused
the no_irq_chip for this purpose, but this does not work out
for platforms which are not converted to the new interrupt
type handling model.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 16 insertions, 0 deletions

diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 961b87591731..e71266c3803e 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -96,6 +96,22 @@ struct irq_chip no_irq_chip = {
 };
 
 /*
+ * Generic dummy implementation which can be used for
+ * real dumb interrupt sources
+ */
+struct irq_chip dummy_irq_chip = {
+        .name           = "dummy",
+        .startup        = noop_ret,
+        .shutdown       = noop,
+        .enable         = noop,
+        .disable        = noop,
+        .ack            = noop,
+        .mask           = noop,
+        .unmask         = noop,
+        .end            = noop,
+};
+
+/*
  * Special, empty irq handler:
  */
 irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs)