acrn-kernel/arch/sh/boards/bigsur/led.c

55 lines
1.3 KiB
C

/*
* linux/arch/sh/kernel/led_bigsur.c
*
* By Dustin McIntire (dustin@sensoria.com) (c)2001
* Derived from led_se.c and led.c, which bore the message:
* 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 Big Sur specific LED code.
*/
#include <asm/io.h>
#include <asm/bigsur/bigsur.h>
static void mach_led(int position, int value)
{
int word;
word = bigsur_inl(BIGSUR_CSLR);
if (value) {
bigsur_outl(word & ~BIGSUR_LED, BIGSUR_CSLR);
} else {
bigsur_outl(word | BIGSUR_LED, BIGSUR_CSLR);
}
}
#ifdef CONFIG_HEARTBEAT
#include <linux/sched.h>
/* Cycle the LED on/off */
void heartbeat_bigsur(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 /* CONFIG_HEARTBEAT */