xgpio_sinit.c

XINLINX公司开发板的嵌入式源代码

/* $Id: xgpio_sinit.c,v 1.1.2.1 2008/02/12 13:28:38 svemula Exp $ */
/******************************************************************************
*
*       XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
*       AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
*       SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
*       OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
*       APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
*       THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
*       AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
*       FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
*       WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
*       IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
*       REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
*       INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
*       FOR A PARTICULAR PURPOSE.
*
*       (c) Copyright 2005-2007 Xilinx Inc.
*       All rights reserved.
*
******************************************************************************/
/**
* @file xgpio_sinit.c
*
* The implementation of the XGpio component's static initialzation
* functionality.
*
* @note
*
* None
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- -----------------------------------------------
* 2.01a jvb  10/13/05 First release
* 2.11a mta  03/21/07 Updated to new coding style
* </pre>
*
*****************************************************************************/

/***************************** Include Files ********************************/

#include "xstatus.h"
#include "xparameters.h"
#include "xgpio_i.h"

/************************** Constant Definitions ****************************/

/**************************** Type Definitions ******************************/

/***************** Macros (Inline Functions) Definitions ********************/

/************************** Variable Definitions ****************************/


/************************** Function Prototypes *****************************/


/******************************************************************************/
/**
* Lookup the device configuration based on the unique device ID.  The table
* ConfigTable contains the configuration info for each device in the system.
*
* @param	DeviceId is the device identifier to lookup.
*
* @return
*		 - A pointer of data type XGpio_Config which points to the
*		device configuration if DeviceID is found.
* 		- NULL if DeviceID is not found.
*
* @note		None.
*
******************************************************************************/
XGpio_Config *XGpio_LookupConfig(u16 DeviceId)
{
	XGpio_Config *CfgPtr = NULL;

	int i;

	for (i = 0; i < XPAR_XGPIO_NUM_INSTANCES; i++) {
		if (XGpio_ConfigTable[i].DeviceId == DeviceId) {
			CfgPtr = &XGpio_ConfigTable[i];
			break;
		}
	}

	return CfgPtr;
}


/****************************************************************************/
/**
* Initialize the XGpio instance provided by the caller based on the
* given DeviceID.
*
* Nothing is done except to initialize the InstancePtr.
*
* @param	InstancePtr is a pointer to an XGpio instance. The memory the
*		pointer references must be pre-allocated by the caller. Further
*		calls to manipulate the component through the XGpio API must be
*		made with this pointer.
*
* @param	DeviceId is the unique id of the device controlled by this XGpio
*		component. Passing in a device id associates the generic XGpio
*		instance to a specific device, as chosen by the caller or
*		application developer.
*
* @return
*		- XST_SUCCESS if the initialization was successfull.
* 		- XST_DEVICE_NOT_FOUND  if the device configuration data was not
*		found for a device with the supplied device ID.
*
* @note		None.
*
*****************************************************************************/
int XGpio_Initialize(XGpio * InstancePtr, u16 DeviceId)
{
	XGpio_Config *ConfigPtr;

	/*
	 * Assert arguments
	 */
	XASSERT_NONVOID(InstancePtr != NULL);

	/*
	 * Lookup configuration data in the device configuration table.
	 * Use this configuration info down below when initializing this
	 * component.
	 */
	ConfigPtr = XGpio_LookupConfig(DeviceId);
	if (ConfigPtr == (XGpio_Config *) NULL) {
		InstancePtr->IsReady = 0;
		return (XST_DEVICE_NOT_FOUND);
	}

	return XGpio_CfgInitialize(InstancePtr, ConfigPtr,
				   ConfigPtr->BaseAddress);
}