arch/all-pc/hpet/allochpetunit.c

   1 /*
   2     Copyright © 1995-2014, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <proto/exec.h>
   7
   8 #include "hpet_intern.h"
   9
  10 /*****************************************************************************
  11
  12     NAME */
  13 #include <proto/hpet.h>
  14
  15         AROS_LH1(ULONG, AllocHPETUnit,
  16
  17 /*  SYNOPSIS */
  18         AROS_LHA(const char *, user, A0),
  19
  20 /*  LOCATION */
  21         struct HPETBase *, base, 2, Hpet)
  22
  23 /*  FUNCTION
  24         Allocate a free HPET timer for use.
  25
  26     INPUTS
  27         user - a string specifying the name of current user. Can not be NULL.
  28
  29     RESULT
  30         A number of HPET timer unit allocated for exclusive use, or -1 if
  31         there was no free HPET.
  32
  33     NOTES
  34
  35     EXAMPLE
  36
  37     BUGS
  38
  39     SEE ALSO
  40
  41     INTERNALS
  42
  43 ******************************************************************************/
  44 {
  45     AROS_LIBFUNC_INIT
  46
  47     ULONG i;
  48
  49     ObtainSemaphore(&base->lock);
  50
  51     for (i = 0; i < base->unitCnt; i++)
  52     {
  53         if (!base->units[i].Owner)
  54         {
  55             base->units[i].Owner = user;
  56
  57             ReleaseSemaphore(&base->lock);
  58             return i;
  59         }
  60     }
  61
  62     ReleaseSemaphore(&base->lock);
  63     return -1;
  64
  65     AROS_LIBFUNC_EXIT
  66 }