kpddrv.c

mips 下的键盘驱动

/****************************************************************************
** Notice: Copyright (c) 1998 LSI Logic Corporation - All Rights Reserved 
**
** File Name: KPDDRV.C
**                          
** $Revision: \main\20010426_1.4_integration_branch\4 $                          
** $Date:     Wed Aug  1 07:32:38 2001 $
**
** Description:
** Keypad driver API and support functions. The keypad driver generates
** key press and key release events as per OpenTV.
**
****************************************************************************/
#include <gendefs.h>    /* Generic Definitions system wide */
#include <keyirdef.h>   /* Common Keypad & IR definitions for buttons */
#include <kpddrv.h>     /* Macros, protos for keypad driver */
#include <osp.h>        /* OSP Prototypes, and macros */
#include <sgo.h>        /* EVB specific GPIO APIs */

/***************************************************************************
** Generic Keypad Access Register. The keypad is mapped through GPIOs.
****************************************************************************/
#define KPD_REGISTER     (*((volatile UINT8 *) 0xB8660000))

/****************************************************************************
** Value (ms) for KPD SCAN 
****************************************************************************/
#define KPD_POLL_INTERVAL         (20) 

/****************************************************************************
** Value for KPD Qusue size 
****************************************************************************/
#define KPD_QUEUE_SIZE        (16)

/****************************************************************************
** Value for KPD Task stack size 
****************************************************************************/
#define KPD_TASK_STACK_SIZE     (0x2000)

/****************************************************************************
** Local Variables
****************************************************************************/
/* Local variables for key sent,counter for LED, and KeypadEnabled */
static UINT8 LastKeySent = 0;
static UINT8 KeypadEnabled;

/****************************************************************************
** Local Function Declarations
****************************************************************************/
static void  KPDTask(void);
static void  (*KeySendCallback)(UINT32, UINT32, UINT32);
static INT32 CallbackAssigned = FALSE;

/* KPDDisable() is not called by anyone, keep it for future use */
/****************************************************************************
** Function KPDDisable(): Disable the keypad interface.
**
** Inputs:  None.
**
** Outputs: None.
**
** Returns: None.
****************************************************************************/
void KPDDisable(void)
{
  KeypadEnabled = FALSE;
}

  
/* KPDEnable() is not called by anyone, keep it for future use */
/****************************************************************************
** Function KPDEnable(): Enable the keypad interface.
**
** Inputs:  None.
**
** Outputs: None.
**
** Returns: None.
****************************************************************************/
void KPDEnable(void)
{
  KeypadEnabled = TRUE;
}


/****************************************************************************
** Function KPDRegisterCallback(): This function is used to register  
** the keysend callback with the keypad driver. The function is also used 
** to unregister by passing a NULL pointer parameter.                             
**
** Inputs:  callbackFunction
**
** Outputs: none.
**
** Returns: SUCCESS.
****************************************************************************/
void KPDRegisterKeySendCallback(void (*callbackFunction)(UINT32, UINT32, UINT32))
{
  KeySendCallback = callbackFunction;
  CallbackAssigned = TRUE;
}                        


/****************************************************************************
** Function KPDInitialize(): Initialize the keypad driver inclduing Keypad 
** Task, Keypad scan task, and check for keypad type
**
** Inputs:  taskPriority, Keypad task Priority.
**
** Outputs: None.
**
** Returns: SUCCESS/FAILURE.
****************************************************************************/
INT32 KPDInitialize(INT32 taskPriority)
{
  UINT32 kpdTaskID;
  INT32  returnCode;

  CallbackAssigned = FALSE;
  
  KPDEnable();

  returnCode = OSPTaskCreate("KPDT", KPD_TASK_STACK_SIZE, KPDTask, 
                             taskPriority, 0, 0, &kpdTaskID);                  
  return (returnCode);
}


/****************************************************************************
** Function KPDTask(): Control loop for the Keypad task. This task 
** flash LED, poll the keypad status, decode Key ID, software debouncing
** and involves the registered callback. This task also generates the 
** PRESS and RELEASE events for OPEN TV requirement. 
**         
** Inputs:  None.
**
** Outputs: None.
**
** Returns: Never. This is a task.
****************************************************************************/
static void KPDTask(void)
{
  UINT8 keyID;
         
  while(TRUE)
  {
    OSPTaskTemporarySleep(KPD_POLL_INTERVAL);   /* sleep for a while */

    if(KeypadEnabled)
    {
      keyID = SGOReadKeypad();
            
      if(keyID)             /* Key press detected */
      {
        if(keyID != LastKeySent)  /* send Key ID with key press */
        {
          if (CallbackAssigned == TRUE)
          {
            KeySendCallback(KEY_PRESS, SOURCE_KEYPAD, keyID);
          }  
        }
      } /* end of if(keyBits) */
      else                  /* Key detected as release or not pressed */
      {
        if(keyID != LastKeySent)  /* send Key ID with key released */
        {
          keyID = 0;
          if (CallbackAssigned == TRUE)
          {
            KeySendCallback(KEY_RELEASE, SOURCE_KEYPAD, LastKeySent);
          }  
        } 
      } /* end of else */
      LastKeySent = keyID;
    } /* end of if(KeypadEnabled) */
  } /* end while (TRUE) */
}