--- zzzz-none-000/linux-2.6.19.2/arch/arm/kernel/process.c	2007-01-10 19:10:37.000000000 +0000
+++ davinci-8020-5505/linux-2.6.19.2/arch/arm/kernel/process.c	2007-06-28 13:54:53.000000000 +0000
@@ -131,6 +131,76 @@
 	}
 }
 
+/*------------------------------------------------------------------------------------------*\
+\*------------------------------------------------------------------------------------------*/
+#if defined(CONFIG_CHECK_IDLE)
+#include <linux/check_idle.h>
+
+static struct _check_idle_action {
+    signed start_idle;
+    signed end_idle;
+    unsigned long run_time;
+    unsigned long idle_time;
+    signed last_report;
+    signed schwelle;
+    signed shift;
+    atomic_t idle; /* >0 if we are in idle */
+    void (*report_function)(unsigned long, unsigned long);
+    signed int (*timer_function)(void);
+} idle_action;
+
+void begin_check_idle(void) {
+    signed int time;
+    if(idle_action.report_function == NULL)
+        return;
+    idle_action.start_idle = (*idle_action.timer_function)();
+    time = idle_action.start_idle - idle_action.end_idle;
+    idle_action.run_time += time > 0 ? time : -time;
+    atomic_set(&idle_action.idle, 1);
+}
+
+void end_check_idle(void) {
+    signed int time;
+    if(atomic_read(&idle_action.idle) == 0) {
+        return;
+    }
+    if(idle_action.report_function == NULL)
+        return;
+    idle_action.end_idle = (*idle_action.timer_function)(); 
+    time = idle_action.end_idle - idle_action.start_idle;
+    idle_action.idle_time += time > 0 ? time : -time;
+
+    if(((signed)jiffies - idle_action.last_report) > idle_action.schwelle) {
+        idle_action.last_report = jiffies;
+        if(idle_action.report_function)
+            (*idle_action.report_function)(idle_action.idle_time, idle_action.run_time);
+        if(idle_action.shift == 0) {
+            idle_action.idle_time = 0;
+            idle_action.run_time  = 0;
+        } else {
+            idle_action.idle_time >>= idle_action.shift;
+            idle_action.run_time  >>= idle_action.shift;
+        }
+    }
+    atomic_set(&idle_action.idle, 0);
+}
+
+void init_check_idle(int shift, int schwelle, void (*report_function)(unsigned long, unsigned long), signed int (*timer_function)(void)) {
+    if(report_function && timer_function) {
+        idle_action.shift           = shift;
+        idle_action.schwelle        = schwelle;
+        idle_action.idle_time       = 0;
+        idle_action.run_time        = 0;
+        idle_action.timer_function  = timer_function;
+        idle_action.report_function = report_function;
+        idle_action.end_idle        = (*idle_action.timer_function)();
+        idle_action.last_report     = jiffies;
+        return;
+    }
+    idle_action.report_function = NULL;
+}
+#endif /*--- #if CONFIG_CHECK_IDLE ---*/
+
 /*
  * The idle thread.  We try to conserve power, while trying to keep
  * overall latency low.  The architecture specific idle is passed
@@ -154,8 +224,12 @@
 		if (!idle)
 			idle = default_idle;
 		leds_event(led_idle_start);
-		while (!need_resched())
+		while (!need_resched()) {
+#if defined(CONFIG_CHECK_IDLE)
+            begin_check_idle();
+#endif /*--- #if CONFIG_CHECK_IDLE ---*/
 			idle();
+        }
 		leds_event(led_idle_end);
 		preempt_enable_no_resched();
 		schedule();