original_kernel/arch/sh/boards/se/7300/led.c

55 lines
1.0 KiB
C

/*
* linux/arch/sh/boards/se/7300/led.c
*
* Derived from linux/arch/sh/boards/se/770x/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 Solution Engine specific LED code.
*/
#include <linux/sched.h>
#include <asm/se7300.h>
/* Cycle the LED's in the clasic Knightrider/Sun pattern */
void heartbeat_7300se(void)
{
static unsigned int cnt = 0, period = 0;
volatile unsigned short *p = (volatile unsigned short *) PA_LED;
static unsigned bit = 0, up = 1;
cnt += 1;
if (cnt < period) {
return;
}
cnt = 0;
/* Go through the points (roughly!):
* f(0)=10, f(1)=16, f(2)=20, f(5)=35,f(inf)->110
*/
period = 110 - ((300 << FSHIFT) / ((avenrun[0] / 5) + (3 << FSHIFT)));
if (up) {
if (bit == 7) {
bit--;
up = 0;
} else {
bit++;
}
} else {
if (bit == 0) {
bit++;
up = 1;
} else {
bit--;
}
}
*p = 1 << (bit + 8);
}