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/*
* linux/arch/sh/stboards/led.c
*
* Copyright (C) 2000 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.
*
* This file contains ST40STB1 HARP and compatible code.
*/
#include <linux/config.h>
#include <asm/io.h>
#include "harp.h"
/* Harp: Flash LD10 (front pannel) connected to EPLD (IC8) */
/* Overdrive: Flash LD1 (front panel) connected to EPLD (IC4) */
/* Works for HARP and overdrive */
static void mach_led(int position, int value)
{
if (value) {
ctrl_outl(EPLD_LED_ON, EPLD_LED);
} else {
ctrl_outl(EPLD_LED_OFF, EPLD_LED);
}
}
#ifdef CONFIG_HEARTBEAT
#include <linux/sched.h>
/* acts like an actual heart beat -- ie thump-thump-pause... */
void heartbeat_harp(void)
{
static unsigned 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;
}
}
#endif
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