/* Configure and start timer for CAN bus I/O transactions */
/* Input: CanBusDescriptor for write and read to/from it  */
/* Output: 0 - start is ok                                */
/*         -1 - not ok (invalid)                          */
int StartCanBusTimer(void)
{
  /* linux interval timer configuration */
  struct itimerval TimerId;
  struct sigaction sigact;

  /* clear all flags and handler before using the signal action */
  memset(&sigact, 0, sizeof(sigact));
  /* define a signal handler for timer interruption */
  sigact.sa_handler = &CanBusTimerHandler;

  if(sigaction(SIGALRM, &sigact, (struct sigaction *)NULL) != 0)
  {
    DEBUG_PRINT("Can not run a signal action!\n");
    return -1;
  }

  /* configure timer */
  /* At first time run the timer handler after minimal time (1 us) */
  TimerId.it_value.tv_sec = 0;
  TimerId.it_value.tv_usec = 1;
  /* and every timing interval run timer handler again */
  TimerId.it_interval.tv_sec = CAN_BUS_TIMEOUT_INTERVAL_SEC;
  TimerId.it_interval.tv_usec = CAN_BUS_TIMEOUT_INTERVAL_NSEC / 1000;
  /* start the timer */
  setitimer(ITIMER_REAL, &TimerId, NULL);

  return 0;
}

/* It works at every CAN_BUS_TIMEOUT_INTERVAL_SEC */
/* Write data to the CAN bus and receive answer from it */
void CanBusTimerHandler(int SignalNumber)
{

  /* write DataToTheCanBus to the CAN bus */
  if((WriteToTheCanBus(CanBusDescriptor, (void *)DataToTheCanBus, UART_CAN_IO_NUMBER_OF_BYTES)) == -1)
  {
    DEBUG_PRINT("Can not write to the CAN bus!\n");
  }
}

root@crux:~# uname -a
Linux crux 3.2.0+ #915 Tue Mar 6 17:15:21 MSK 2012 armv5tejl GNU/Linux
root@crux:~# cat /proc/timer_list
Timer List Version: v0.6
HRTIMER_MAX_CLOCK_BASES: 3
now at 2012233776199 nsecs

cpu: 0
clock 0:
  .base:       c05256a8
  .index:      0
  .resolution: 5000000 nsecs
  .get_time:   ktime_get