| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/sh/stboards/led.c |
| 3 | * |
| 4 | * Copyright (C) 2000 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 | * This file contains ST40STB1 HARP and compatible code. |
| 10 | */ |
| 11 | |
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/io.h> |
| 13 | #include <asm/harp/harp.h> |
| 14 | |
| 15 | /* Harp: Flash LD10 (front pannel) connected to EPLD (IC8) */ |
| 16 | /* Overdrive: Flash LD1 (front panel) connected to EPLD (IC4) */ |
| 17 | /* Works for HARP and overdrive */ |
| 18 | static void mach_led(int position, int value) |
| 19 | { |
| 20 | if (value) { |
| 21 | ctrl_outl(EPLD_LED_ON, EPLD_LED); |
| 22 | } else { |
| 23 | ctrl_outl(EPLD_LED_OFF, EPLD_LED); |
| 24 | } |
| 25 | } |
| 26 | |
| 27 | #ifdef CONFIG_HEARTBEAT |
| 28 | |
| 29 | #include <linux/sched.h> |
| 30 | |
| 31 | /* acts like an actual heart beat -- ie thump-thump-pause... */ |
| 32 | void heartbeat_harp(void) |
| 33 | { |
| 34 | static unsigned cnt = 0, period = 0, dist = 0; |
| 35 | |
| 36 | if (cnt == 0 || cnt == dist) |
| 37 | mach_led( -1, 1); |
| 38 | else if (cnt == 7 || cnt == dist+7) |
| 39 | mach_led( -1, 0); |
| 40 | |
| 41 | if (++cnt > period) { |
| 42 | cnt = 0; |
| 43 | /* The hyperbolic function below modifies the heartbeat period |
| 44 | * length in dependency of the current (5min) load. It goes |
| 45 | * through the points f(0)=126, f(1)=86, f(5)=51, |
| 46 | * f(inf)->30. */ |
| 47 | period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30; |
| 48 | dist = period / 4; |
| 49 | } |
| 50 | } |
| 51 | #endif |