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Diffstat (limited to 'arch/sh64/kernel/led.c')
| -rw-r--r-- | arch/sh64/kernel/led.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/sh64/kernel/led.c b/arch/sh64/kernel/led.c new file mode 100644 index 00000000000..cf993c4a9fd --- /dev/null +++ b/arch/sh64/kernel/led.c @@ -0,0 +1,41 @@ +/* + * arch/sh64/kernel/led.c + * + * Copyright (C) 2002 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. + * + * Flash the LEDs + */ +#include <linux/config.h> +#include <linux/stddef.h> +#include <linux/sched.h> + +void mach_led(int pos, int val); + +/* acts like an actual heart beat -- ie thump-thump-pause... */ +void heartbeat(void) +{ + static unsigned int 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; + } +} + |