delay.h 1.2 KB

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  1. #ifndef _LINUX_DELAY_H
  2. #define _LINUX_DELAY_H
  3. /*
  4. * Copyright (C) 1993 Linus Torvalds
  5. *
  6. * Delay routines, using a pre-computed "loops_per_jiffy" value.
  7. */
  8. extern unsigned long loops_per_jiffy;
  9. #include <asm/delay.h>
  10. /*
  11. * Using udelay() for intervals greater than a few milliseconds can
  12. * risk overflow for high loops_per_jiffy (high bogomips) machines. The
  13. * mdelay() provides a wrapper to prevent this. For delays greater
  14. * than MAX_UDELAY_MS milliseconds, the wrapper is used. Architecture
  15. * specific values can be defined in asm-???/delay.h as an override.
  16. * The 2nd mdelay() definition ensures GCC will optimize away the
  17. * while loop for the common cases where n <= MAX_UDELAY_MS -- Paul G.
  18. */
  19. #ifndef MAX_UDELAY_MS
  20. #define MAX_UDELAY_MS 5
  21. #endif
  22. #ifndef mdelay
  23. #define mdelay(n) (\
  24. (__builtin_constant_p(n) && (n)<=MAX_UDELAY_MS) ? udelay((n)*1000) : \
  25. ({unsigned long __ms=(n); while (__ms--) udelay(1000);}))
  26. #endif
  27. #ifndef ndelay
  28. #define ndelay(x) udelay(((x)+999)/1000)
  29. #endif
  30. void calibrate_delay(void);
  31. void msleep(unsigned int msecs);
  32. unsigned long msleep_interruptible(unsigned int msecs);
  33. static inline void ssleep(unsigned int seconds)
  34. {
  35. msleep(seconds * 1000);
  36. }
  37. #endif /* defined(_LINUX_DELAY_H) */