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-rw-r--r--arch/sh64/kernel/led.c41
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 0000000..cf993c4
--- /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;
+ }
+}
+
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