1/* 2 * arch/sh64/kernel/led.c 3 * 4 * Copyright (C) 2002 Stuart Menefy <stuart.menefy@st.com> 5 * 6 * May be copied or modified under the terms of the GNU General Public 7 * License. See linux/COPYING for more information. 8 * 9 * Flash the LEDs 10 */ 11#include <linux/stddef.h> 12#include <linux/sched.h> 13 14void mach_led(int pos, int val); 15 16/* acts like an actual heart beat -- ie thump-thump-pause... */ 17void heartbeat(void) 18{ 19 static unsigned int cnt = 0, period = 0, dist = 0; 20 21 if (cnt == 0 || cnt == dist) { 22 mach_led(-1, 1); 23 } else if (cnt == 7 || cnt == dist + 7) { 24 mach_led(-1, 0); 25 } 26 27 if (++cnt > period) { 28 cnt = 0; 29 30 /* 31 * The hyperbolic function below modifies the heartbeat period 32 * length in dependency of the current (5min) load. It goes 33 * through the points f(0)=126, f(1)=86, f(5)=51, f(inf)->30. 34 */ 35 period = ((672 << FSHIFT) / (5 * avenrun[0] + 36 (7 << FSHIFT))) + 30; 37 dist = period / 4; 38 } 39} 40