xiic_slave.c

FPGA 并行NOR FLash的操作相关

/* $Id: xiic_slave.c,v 1.1 2007/12/03 15:44:58 meinelte 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 2002 Xilinx Inc.
*       All rights reserved.
*
******************************************************************************/
/*****************************************************************************/
/**
*
* @file xiic_slave.c
*
* Contains slave functions for the XIic component. This file is necessary when
* slave operations, sending and receiving data as a slave on the IIC bus,
* are desired.
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- --- ------- -----------------------------------------------
* 1.01b jhl 3/26/02 repartioned the driver
* 1.01c ecm 12/05/02 new rev
* 1.13a wgr  03/22/07 Converted to new coding style.
* </pre>
*
****************************************************************************/

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

#include "xiic.h"
#include "xiic_i.h"
#include "xio.h"

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


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


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


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

static void AddrAsSlaveHandler(XIic * InstancePtr);
static void NotAddrAsSlaveHandler(XIic * InstancePtr);
static void RecvSlaveData(XIic * InstancePtr);
static void SendSlaveData(XIic * InstancePtr);

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


/*****************************************************************************
*
* This function includes slave code such that slave events will be processsed.
* It is necessary to allow slave code to be optional to reduce the size of
* the driver.  This function may be called at any time but must be prior to
* being selected as a slave on the IIC bus.  This function may be called prior
* to the Initialize() function and must be called before any functions in the
* file are called.
*
******************************************************************************/
void XIic_SlaveInclude()
{
	XIic_AddrAsSlaveFuncPtr = AddrAsSlaveHandler;
	XIic_NotAddrAsSlaveFuncPtr = NotAddrAsSlaveHandler;
	XIic_RecvSlaveFuncPtr = RecvSlaveData;
	XIic_SendSlaveFuncPtr = SendSlaveData;
}

/*****************************************************************************
*
* This function sends data as a slave on the IIC bus and should not be called
* until an event has occurred that indicates the device has been selected by
* a master attempting read from the slave (XII_MASTER_READ_EVENT).
*
*
* @param    InstancePtr is a pointer to the XIic instance to be worked on.
* @param    TxMsgPtr is a pointer to the data to be transmitted
* @param    ByteCount is the number of message bytes to be sent
*
* @return
*
* - XST_SUCCESS indicates the message transmission has been initiated.
* - XST_IIC_NOT_SLAVE indicates the device has not been selected to be a slave
* on the IIC bus such that data cannot be sent.
*
******************************************************************************/
int XIic_SlaveSend(XIic * InstancePtr, u8 *TxMsgPtr, int ByteCount)
{
	u8 IntrStatus;
	u8 Status;

	/* If the device is not a slave on the IIC bus then indicate an error
	 * because data cannot be sent on the bus
	 */
	Status = XIo_In8(InstancePtr->BaseAddress + XIIC_SR_REG_OFFSET);
	if ((Status & XIIC_SR_ADDR_AS_SLAVE_MASK) == 0) {
		return XST_IIC_NOT_SLAVE;
	}

	XIic_mEnterCriticalRegion(InstancePtr->BaseAddress);

	/* Save message state and invalidate the receive buffer pointer to indicate
	 * the direction of transfer is sending
	 */
	InstancePtr->SendByteCount = ByteCount;
	InstancePtr->SendBufferPtr = TxMsgPtr;
	InstancePtr->RecvBufferPtr = NULL;

	/* Start sending the specified data and then interrupt processing will
	 * complete it
	 */
	XIic_TransmitFifoFill(InstancePtr, XIIC_SLAVE_ROLE);

	/* Clear any pending Tx empty, Tx Error and interrupt then enable them.
	 * The Tx error interrupt indicates when the message is complete.
	 * If data remaining to be sent, clear and enable Tx