[ARM PATCH] 1941/2: End-of-interrupt (irq_finish) macro on ARM

Patch from SAN People

On some ARM-based processor's (eg, Atmel's AT91RM9200) it is necessary
to signal the end-of-interrupt to the interrupt controller. This is
necessary so it can restore its internal priority levels, etc.
This patch is equivalent to the version in the current 2.4 kernels.
Patch now updated to 2.6.11

Signed-off-by: Andrew Victor
Signed-off-by: Russell King

arch/arm/kernel/irq.c

@@ -55,6 +55,13 @@ static LIST_HEAD(irq_pending);
 struct irqdesc irq_desc[NR_IRQS];
 void (*init_arch_irq)(void) __initdata = NULL;
 
+/*
+ * No architecture-specific irq_finish function defined in arm/arch/irqs.h.
+ */
+#ifndef irq_finish
+#define irq_finish(irq) do { } while (0)
+#endif
+
 /*
  * Dummy mask/unmask handler
  */
@@ -532,6 +539,8 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
 	if (!list_empty(&irq_pending))
 		do_pending_irqs(regs);
 
+	irq_finish(irq);
+
 	spin_unlock(&irq_controller_lock);
 	irq_exit();
 }