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-rw-r--r--include/linux/delay.h50
1 files changed, 50 insertions, 0 deletions
diff --git a/include/linux/delay.h b/include/linux/delay.h
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--- /dev/null
+++ b/include/linux/delay.h
@@ -0,0 +1,50 @@
+#ifndef _LINUX_DELAY_H
+#define _LINUX_DELAY_H
+
+/*
+ * Copyright (C) 1993 Linus Torvalds
+ *
+ * Delay routines, using a pre-computed "loops_per_jiffy" value.
+ */
+
+extern unsigned long loops_per_jiffy;
+
+#include <asm/delay.h>
+
+/*
+ * Using udelay() for intervals greater than a few milliseconds can
+ * risk overflow for high loops_per_jiffy (high bogomips) machines. The
+ * mdelay() provides a wrapper to prevent this. For delays greater
+ * than MAX_UDELAY_MS milliseconds, the wrapper is used. Architecture
+ * specific values can be defined in asm-???/delay.h as an override.
+ * The 2nd mdelay() definition ensures GCC will optimize away the
+ * while loop for the common cases where n <= MAX_UDELAY_MS -- Paul G.
+ */
+
+#ifndef MAX_UDELAY_MS
+#define MAX_UDELAY_MS 5
+#endif
+
+#ifdef notdef
+#define mdelay(n) (\
+ {unsigned long __ms=(n); while (__ms--) udelay(1000);})
+#else
+#define mdelay(n) (\
+ (__builtin_constant_p(n) && (n)<=MAX_UDELAY_MS) ? udelay((n)*1000) : \
+ ({unsigned long __ms=(n); while (__ms--) udelay(1000);}))
+#endif
+
+#ifndef ndelay
+#define ndelay(x) udelay(((x)+999)/1000)
+#endif
+
+void calibrate_delay(void);
+void msleep(unsigned int msecs);
+unsigned long msleep_interruptible(unsigned int msecs);
+
+static inline void ssleep(unsigned int seconds)
+{
+ msleep(seconds * 1000);
+}
+
+#endif /* defined(_LINUX_DELAY_H) */