reactos/ntoskrnl/io/timer.c

   1 /* $Id: timer.c,v 1.11 2003/12/30 18:52:04 fireball 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 static VOID STDCALL
  27 IoTimerCallback(IN PKDPC Dpc,
  28                 IN PVOID DeferredContext,
  29                 IN PVOID SystemArgument1,
  30                 IN PVOID SystemArgument2)
  31 {
  32   PIO_TIMER Timer = (PIO_TIMER) DeferredContext;
  33
  34   Timer->TimerRoutine(Timer->DeviceObject, Timer->Context);
  35 }
  36
  37 /*
  38  * @implemented
  39  */
  40 NTSTATUS
  41 STDCALL
  42 IoInitializeTimer(PDEVICE_OBJECT DeviceObject,
  43                            PIO_TIMER_ROUTINE TimerRoutine,
  44                            PVOID Context)
  45 /*
  46  * FUNCTION: Sets up a driver-supplied IoTimer routine associated with a given
  47  * device object
  48  * ARGUMENTS:
  49  *     DeviceObject = Device object whose timer is be initialized
  50  *     TimerRoutine = Driver supplied routine which will be called once per
  51  *                    second if the timer is active
  52  *     Context = Driver supplied context to be passed to the TimerRoutine
  53  * RETURNS: Status
  54  */
  55 {
  56    DeviceObject->Timer = ExAllocatePoolWithTag(NonPagedPool, sizeof(IO_TIMER),
  57                                                TAG_IO_TIMER);
  58    DeviceObject->Timer->DeviceObject = DeviceObject;
  59    DeviceObject->Timer->TimerRoutine = TimerRoutine;
  60    DeviceObject->Timer->Context = Context;
  61    KeInitializeTimer(&(DeviceObject->Timer->timer));
  62    KeInitializeDpc(&(DeviceObject->Timer->dpc),
  63                    IoTimerCallback, DeviceObject->Timer);
  64
  65    return(STATUS_SUCCESS);
  66 }
  67
  68 /*
  69  * @implemented
  70  */
  71 VOID
  72 STDCALL
  73 IoStartTimer(PDEVICE_OBJECT DeviceObject)
  74 /*
  75  * FUNCTION: Starts a timer so the driver-supplied IoTimer routine will be
  76  * called once per second
  77  * ARGUMENTS:
  78  *       DeviceObject = Device whose timer is to be started
  79  */
  80 {
  81    LONGLONG lli;
  82    LARGE_INTEGER li;
  83
  84    lli = -1000000;
  85    li = *(LARGE_INTEGER *)&lli;
  86
  87    KeSetTimerEx(&DeviceObject->Timer->timer,
  88                 li,
  89                 1000,
  90                 &(DeviceObject->Timer->dpc));
  91 }
  92
  93 /*
  94  * @implemented
  95  */
  96 VOID
  97 STDCALL
  98 IoStopTimer(PDEVICE_OBJECT DeviceObject)
  99 /*
 100  * FUNCTION: Disables for a specified device object so the driver-supplied
 101  * IoTimer is not called
 102  * ARGUMENTS:
 103  *        DeviceObject = Device whose timer is to be stopped
 104  */
 105 {
 106    KeCancelTimer(&(DeviceObject->Timer->timer));
 107 }
 108
 109
 110 /* EOF */