led.c 1.1 KB

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  1. /*
  2. * linux/arch/sh/boards/renesas/rts7751r2d/led.c
  3. *
  4. * Copyright (C) Atom Create Engineering Co., Ltd.
  5. *
  6. * May be copied or modified under the terms of GNU General Public
  7. * License. See linux/COPYING for more information.
  8. *
  9. * This file contains Renesas Technology Sales RTS7751R2D specific LED code.
  10. */
  11. #include <asm/io.h>
  12. #include <asm/rts7751r2d/rts7751r2d.h>
  13. #ifdef CONFIG_HEARTBEAT
  14. #include <linux/sched.h>
  15. /* Cycle the LED's in the clasic Knightriger/Sun pattern */
  16. void heartbeat_rts7751r2d(void)
  17. {
  18. static unsigned int cnt = 0, period = 0;
  19. volatile unsigned short *p = (volatile unsigned short *)PA_OUTPORT;
  20. static unsigned bit = 0, up = 1;
  21. cnt += 1;
  22. if (cnt < period)
  23. return;
  24. cnt = 0;
  25. /* Go through the points (roughly!):
  26. * f(0)=10, f(1)=16, f(2)=20, f(5)=35, f(int)->110
  27. */
  28. period = 110 - ((300 << FSHIFT)/((avenrun[0]/5) + (3<<FSHIFT)));
  29. *p = 1 << bit;
  30. if (up)
  31. if (bit == 7) {
  32. bit--;
  33. up = 0;
  34. } else
  35. bit++;
  36. else if (bit == 0)
  37. up = 1;
  38. else
  39. bit--;
  40. }
  41. #endif /* CONFIG_HEARTBEAT */
  42. void rts7751r2d_led(unsigned short value)
  43. {
  44. ctrl_outw(value, PA_OUTPORT);
  45. }