reactos/ntoskrnl/io/timer.c

   1 /* $Id: timer.c,v 1.6 2001/03/07 16:48:42 dwelch Exp $
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/io/timer.c
   6  * PURPOSE:         io timers
   7  * PROGRAMMER:      David Welch (welch@mcmail.com)
   8  * UPDATE HISTORY:
   9  *                  Created 22/05/98
  10  */
  11
  12 /* INCLUDES *****************************************************************/
  13
  14 #include <ddk/ntddk.h>
  15 #include <internal/pool.h>
  16
  17 #define NDEBUG
  18 #include <internal/debug.h>
  19
  20 /* GLBOALS *******************************************************************/
  21
  22 #define TAG_IO_TIMER      TAG('I', 'O', 'T', 'M')
  23
  24 /* FUNCTIONS *****************************************************************/
  25
  26 NTSTATUS
  27 STDCALL
  28 IoInitializeTimer(PDEVICE_OBJECT DeviceObject,
  29                            PIO_TIMER_ROUTINE TimerRoutine,
  30                            PVOID Context)
  31 /*
  32  * FUNCTION: Sets up a driver-supplied IoTimer routine associated with a given
  33  * device object
  34  * ARGUMENTS:
  35  *     DeviceObject = Device object whose timer is be initialized
  36  *     TimerRoutine = Driver supplied routine which will be called once per
  37  *                    second if the timer is active
  38  *     Context = Driver supplied context to be passed to the TimerRoutine
  39  * RETURNS: Status
  40  */
  41 {
  42    DeviceObject->Timer = ExAllocatePoolWithTag(NonPagedPool, sizeof(IO_TIMER),
  43                                                TAG_IO_TIMER);
  44    KeInitializeTimer(&(DeviceObject->Timer->timer));
  45    KeInitializeDpc(&(DeviceObject->Timer->dpc),
  46                    (PKDEFERRED_ROUTINE)TimerRoutine,Context);
  47
  48    return(STATUS_SUCCESS);
  49 }
  50
  51 VOID
  52 STDCALL
  53 IoStartTimer(PDEVICE_OBJECT DeviceObject)
  54 /*
  55  * FUNCTION: Starts a timer so the driver-supplied IoTimer routine will be
  56  * called once per second
  57  * ARGUMENTS:
  58  *       DeviceObject = Device whose timer is to be started
  59  */
  60 {
  61    long long int lli;
  62    LARGE_INTEGER li;
  63
  64    lli = -1000000;
  65    li = *(LARGE_INTEGER *)&lli;
  66
  67    KeSetTimerEx(&DeviceObject->Timer->timer,
  68                 li,
  69                 1000,
  70                 &(DeviceObject->Timer->dpc));
  71 }
  72
  73 VOID
  74 STDCALL
  75 IoStopTimer(PDEVICE_OBJECT DeviceObject)
  76 /*
  77  * FUNCTION: Disables for a specified device object so the driver-supplied
  78  * IoTimer is not called
  79  * ARGUMENTS:
  80  *        DeviceObject = Device whose timer is to be stopped
  81  */
  82 {
  83    KeCancelTimer(&(DeviceObject->Timer->timer));
  84 }
  85
  86
  87 /* EOF */