linux/arch/sh/boards/sh03/led.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

50 lines
839 B
C

/*
* linux/arch/sh/boards/sh03/led.c
*
* Copyright (C) 2004 Saito.K Interface Corporation.
*
* This file contains Interface CTP/PCI-SH03 specific LED code.
*/
#include <linux/config.h>
#include <linux/sched.h>
/* Cycle the LED's in the clasic Knightrider/Sun pattern */
void heartbeat_sh03(void)
{
static unsigned int cnt = 0, period = 0;
volatile unsigned char* p = (volatile unsigned char*)0xa0800000;
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;
}