Index: linux-2.6.24.3/arch/powerpc/kernel/idle.c
===================================================================
--- linux-2.6.24.3.orig/arch/powerpc/kernel/idle.c	2008-02-29 14:49:40.000000000 +0100
+++ linux-2.6.24.3/arch/powerpc/kernel/idle.c	2008-02-29 16:29:23.000000000 +0100
@@ -19,6 +19,7 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/leds.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/smp.h>
@@ -51,6 +52,12 @@
 __setup("powersave=off", powersave_off);
 
 /*
+ * CPU activity indicator.
+ */
+void (*leds_idle)(int is_idle);
+EXPORT_SYMBOL(leds_idle);
+
+/*
  * The body of the idle task.
  */
 void cpu_idle(void)
@@ -64,7 +71,8 @@
 		while (!need_resched() && !need_resched_delayed() &&
 				!cpu_should_die()) {
 			ppc64_runlatch_off();
-
+            if (leds_idle)
+              leds_idle(1);
 			if (ppc_md.power_save) {
 				clear_thread_flag(TIF_POLLING_NRFLAG);
 				/*
@@ -99,6 +107,8 @@
 		if (cpu_should_die())
 			cpu_die();
 		__preempt_enable_no_resched();
+        if (leds_idle)
+          leds_idle(0);
 		schedule();
 		preempt_disable();
 	}