42 lines
		
	
	
	
		
			955 B
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			42 lines
		
	
	
	
		
			955 B
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * arch/sh64/kernel/led.c | ||
|  |  * | ||
|  |  * Copyright (C) 2002 Stuart Menefy <stuart.menefy@st.com> | ||
|  |  * | ||
|  |  * May be copied or modified under the terms of the GNU General Public | ||
|  |  * License.  See linux/COPYING for more information. | ||
|  |  * | ||
|  |  * Flash the LEDs | ||
|  |  */ | ||
|  | #include <linux/config.h>
 | ||
|  | #include <linux/stddef.h>
 | ||
|  | #include <linux/sched.h>
 | ||
|  | 
 | ||
|  | void mach_led(int pos, int val); | ||
|  | 
 | ||
|  | /* acts like an actual heart beat -- ie thump-thump-pause... */ | ||
|  | void heartbeat(void) | ||
|  | { | ||
|  | 	static unsigned int cnt = 0, period = 0, dist = 0; | ||
|  | 
 | ||
|  | 	if (cnt == 0 || cnt == dist) { | ||
|  | 		mach_led(-1, 1); | ||
|  | 	} else if (cnt == 7 || cnt == dist + 7) { | ||
|  | 		mach_led(-1, 0); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	if (++cnt > period) { | ||
|  | 		cnt = 0; | ||
|  | 
 | ||
|  | 		/*
 | ||
|  | 		 * The hyperbolic function below modifies the heartbeat period | ||
|  | 		 * length in dependency of the current (5min) load. It goes | ||
|  | 		 * through the points f(0)=126, f(1)=86, f(5)=51, f(inf)->30. | ||
|  | 		 */ | ||
|  | 		period = ((672 << FSHIFT) / (5 * avenrun[0] + | ||
|  | 					    (7 << FSHIFT))) + 30; | ||
|  | 		dist = period / 4; | ||
|  | 	} | ||
|  | } | ||
|  | 
 |