Sample Code
Windows Driver Samples/ PCMCIA Smart Card Driver/ C++/ pscr/ pscrrdwr.c/
/*++
Copyright (c) 1997 - 1999 SCM Microsystems, Inc.
Module Name:
PscrRdWr.c
Abstract:
Hardware access functions for SCM PSCR smartcard reader
Author:
Andreas Straub
Environment:
Win 95 Sys... calls are resolved by Pscr95Wrap.asm functions and
Pscr95Wrap.h macros, resp.
NT 4.0 Sys... functions resolved by PscrNTWrap.c functions and
PscrNTWrap.h macros, resp.
Notes:
The file pscrrdwr.c was reviewed by LCA in June 2011 and per license is
acceptable for Microsoft use under Dealpoint ID 178449.
Revision History:
Andreas Straub 7/16/1997 1.00 Initial Version
Klaus Schuetz 9/20/1997 1.01 Timing changed
Andreas Straub 9/24/1997 1.02 Low Level error handling,
minor bugfixes, clanup
--*/
#include <PscrNT.h>
#include <PscrCmd.h>
#include <PscrRdWr.h>
#pragma optimize( "", off )
VOID
PscrFlushInterface( PREADER_EXTENSION ReaderExtension )
/*++
PscrFlushInterface:
Read & discard data from the pcmcia interface
Arguments:
ReaderExtension context of call
Return Value:
void
--*/
{
UCHAR Status;
ULONG Length;
PPSCR_REGISTERS IOBase;
IOBase = ReaderExtension->IOBase;
Status = READ_PORT_UCHAR( &IOBase->CmdStatusReg );
if (( Status & PSCR_DATA_AVAIL_BIT ) && ( Status & PSCR_FREE_BIT )) {
// take control over
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, PSCR_HOST_CONTROL_BIT );
// get number of available bytes
Length = ((ULONG)READ_PORT_UCHAR( &IOBase->SizeMSReg )) << 8;
Length |= READ_PORT_UCHAR( &IOBase->SizeLSReg );
// perform a dummy read
while ( Length-- ) {
READ_PORT_UCHAR( &IOBase->DataReg );
}
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, CLEAR_BIT );
}
return;
}
NTSTATUS
PscrRead(
_In_ PREADER_EXTENSION ReaderExtension, // context of call
_Out_writes_bytes_(DataLen) PUCHAR pData, // ptr to data buffer
_In_ ULONG DataLen, // length of data
_Out_ PULONG pNBytes // number of bytes read
)
/*++
PscrRead:
wait until data available & transfer data from reader to host
Arguments:
ReaderExtension context of call
pData ptr to data buffer
DataLen length of data buffer
pNBytes number of bytes returned
Return Value:
STATUS_SUCCESS
STATUS_BUFFER_TOO_SMALL
STATUS_UNSUCCESSFUL
--*/
{
NTSTATUS NTStatus = STATUS_UNSUCCESSFUL;
ULONG NBytes = 0;
NTStatus = PscrReadDirect(
ReaderExtension,
pData,
DataLen,
&NBytes
);
if( NTStatus == STATUS_SUCCESS )
{
// error check
if( pData[ NBytes - 1 ] !=
PscrCalculateLRC( pData, (USHORT)( NBytes-1 )))
{
NTStatus = STATUS_CRC_ERROR;
}
else
{
USHORT ReaderStatus;
//
// Evaluation of reader errors. A reader error is indicated
// if the T1 length is 2 and the Nad indicates that this
// packet came from the reader
//
if( ( ( pData[ PSCR_NAD ] & 0x0F ) == 0x01 ) &&
( pData[ PSCR_LEN ] == 0x02 )
)
{
ReaderStatus = (( USHORT ) pData[3] ) << 8;
ReaderStatus |= (( USHORT ) pData[4] );
if( ( ReaderStatus != 0x9000 ) &&
( ReaderStatus != 0x9001 )
)
{
NBytes = 0;
if( ReaderStatus == PSCR_SW_PROTOCOL_ERROR )
{
NTStatus = STATUS_IO_TIMEOUT;
}
else if( ReaderStatus == PSCR_SW_NO_ICC )
{
NTStatus = STATUS_NO_MEDIA;
}
else
{
NTStatus = STATUS_UNSUCCESSFUL;
}
}
}
// check freeze data
if( ( NBytes == 9 ) &&
( pData[ PSCR_NAD ] == 0x21 ) &&
( pData[ PSCR_INF ] == TAG_FREEZE_EVENTS ))
{
UCHAR CardState;
CardState = pData[PSCR_INF + 2] == DEVICE_ICC1 ?
PSCR_ICC_PRESENT : PSCR_ICC_ABSENT;
if( ( ReaderExtension->CompletionRoutine != NULL ) &&
( ReaderExtension->TrackingContext != NULL ))
{
// Freeze Data read
ReaderExtension->RequestInterrupt = FALSE; // set in DPC/reset here
(ReaderExtension->CompletionRoutine)(
ReaderExtension->TrackingContext,
CardState,
FALSE
);
}
NBytes = 0;
if( CardState == PSCR_ICC_ABSENT )
{
NTStatus = STATUS_NO_MEDIA;
}
}
}
}
// write number of bytes received
*pNBytes = NBytes;
if( NBytes )
{
NTStatus = STATUS_SUCCESS;
}
return ( NTStatus );
}
NTSTATUS
PscrReadDirect(
PREADER_EXTENSION ReaderExtension,
_Out_writes_bytes_(DataLen) PUCHAR pData,
ULONG DataLen,
PULONG pNBytes
)
/*++
PscrReadDirect:
wait until data available & transfer data from reader to host
Arguments:
ReaderExtension context of call
pData ptr to data buffer
DataLen length of data buffer
pNBytes number of bytes returned
Return Value:
STATUS_SUCCESS
STATUS_BUFFER_TOO_SMALL
STATUS_UNSUCCESSFUL
--*/
{
NTSTATUS NTStatus = STATUS_UNSUCCESSFUL;
PPSCR_REGISTERS IOBase;
USHORT InDataLen;
ULONG Idx;
IOBase = ReaderExtension->IOBase;
// wait until interface is ready to transfer
InDataLen = 0;
if( NT_SUCCESS( NTStatus = PscrWait( ReaderExtension, PSCR_DATA_AVAIL_BIT | PSCR_FREE_BIT )))
{
// take control over
SysDelay( DELAY_PSCR_WAIT );
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, PSCR_HOST_CONTROL_BIT );
SysDelay( DELAY_PSCR_WAIT );
// get number of available bytes
InDataLen = ( READ_PORT_UCHAR( &IOBase->SizeMSReg ) << 8 );
InDataLen |= READ_PORT_UCHAR( &IOBase->SizeLSReg );
// check buffer size. if buffer to small, the data will be discarded
if( ( ULONG )InDataLen <= DataLen )
{
// read data
for (Idx = 0; Idx < InDataLen; Idx++) {
pData[ Idx ] = READ_PORT_UCHAR( &IOBase->DataReg );
if(( READ_PORT_UCHAR( &IOBase->CmdStatusReg )) == 0x02 )
{
Idx++;
break;
}
}
if( Idx < ( ULONG )InDataLen )
{
if(( InDataLen - Idx ) == 1 )
{
pData[ Idx ] = PscrCalculateLRC( pData, ( USHORT ) Idx );
}
else
{
InDataLen = 0;
NTStatus = STATUS_UNSUCCESSFUL;
}
}
}
else
{
// flush interface in case of wrong buffer size
do
{
READ_PORT_UCHAR( &IOBase->DataReg );
} while( --InDataLen );
NTStatus = STATUS_BUFFER_TOO_SMALL;
}
// clean up
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, CLEAR_BIT );
}
ReaderExtension->RequestPending = FALSE;
// write number of bytes received
if( InDataLen )
{
if( pNBytes != NULL )
{
( *pNBytes ) = ( ULONG ) InDataLen;
}
NTStatus = STATUS_SUCCESS;
}
return ( NTStatus );
}
NTSTATUS
PscrWrite(
PREADER_EXTENSION ReaderExtension,
PUCHAR pData,
ULONG DataLen,
PULONG pNBytes
)
/*++
PscrWrite:
calculates the LRC of the buffer & sends command to the reader
Arguments:
ReaderExtension context of call
pData ptr to data buffer
DataLen length of data buffer (exclusive LRC!)
pNBytes number of bytes written
Return Value:
return value of PscrWriteDirect
--*/
{
NTSTATUS NTStatus;
// Add the EDC field to the end of the data
pData[ DataLen ] = PscrCalculateLRC( pData, ( USHORT ) DataLen );
// Send buffer
NTStatus = PscrWriteDirect(
ReaderExtension,
pData,
DataLen + PSCR_EPILOGUE_LENGTH,
pNBytes
);
return( NTStatus );
}
NTSTATUS
PscrWriteDirect(
PREADER_EXTENSION ReaderExtension,
PUCHAR pData,
ULONG DataLen,
PULONG pNBytes
)
/*++
PscrWriteDirect:
sends command to the reader. The LRC / CRC must be calculated by caller!
Arguments:
ReaderExtension context of call
pData ptr to data buffer
DataLen length of data buffer (exclusive LRC!)
pNBytes number of bytes written
Return Value:
STATUS_SUCCESS
STATUS_DEVICE_BUSY
--*/
{
NTSTATUS NTStatus = STATUS_SUCCESS;
UCHAR Status;
PPSCR_REGISTERS IOBase;
IOBase = ReaderExtension->IOBase;
// in case of card change, there may be data available
Status = READ_PORT_UCHAR( &IOBase->CmdStatusReg );
if ( Status & PSCR_DATA_AVAIL_BIT ) {
NTStatus = STATUS_DEVICE_BUSY;
} else {
//
// wait until reader is ready
//
ReaderExtension->RequestPending = TRUE;
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, PSCR_HOST_CONTROL_BIT );
NTStatus = PscrWait( ReaderExtension, PSCR_FREE_BIT );
if ( NT_SUCCESS( NTStatus )) {
ULONG Idx;
// take control over
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, PSCR_HOST_CONTROL_BIT );
// write the buffer size
WRITE_PORT_UCHAR( &IOBase->SizeMSReg, ( UCHAR )( DataLen >> 8 ));
SysDelay( DELAY_WRITE_PSCR_REG );
WRITE_PORT_UCHAR( &IOBase->SizeLSReg, ( UCHAR )( DataLen & 0x00FF ));
SysDelay( DELAY_WRITE_PSCR_REG );
// write data
for (Idx = 0; Idx < DataLen; Idx++) {
WRITE_PORT_UCHAR( &IOBase->DataReg, pData[ Idx ] );
}
if ( pNBytes != NULL ) {
*pNBytes = DataLen;
}
}
// clean up
WRITE_PORT_UCHAR( &IOBase->CmdStatusReg, CLEAR_BIT );
}
return( NTStatus );
}
UCHAR
PscrCalculateLRC(
PUCHAR pData,
USHORT DataLen
)
/*++
PscrCalculateLRC:
calculates the XOR LRC of a buffer.
Arguments:
pData ptr to data buffer
DataLen length of range
Return Value:
LRC
--*/
{
UCHAR Lrc;
USHORT Idx;
//
// Calculate LRC by XORing all the bytes.
//
Lrc = pData[ 0 ];
for ( Idx = 1 ; Idx < DataLen; Idx++ ) {
Lrc ^= pData[ Idx ];
}
return( Lrc );
}
NTSTATUS
PscrWait(
PREADER_EXTENSION ReaderExtension,
UCHAR Mask
)
/*++
PscrWait:
Test the status port of the reader until ALL bits in the mask are set.
The maximum of time until DEVICE_BUSY is returned is approx.
MaxRetries * DELAY_PSCR_WAIT if MaxRetries != 0.
If MaxRetries = 0 the driver waits until the requested status is reported or the
user defines a timeout.
Arguments:
ReaderExtension context of call
Mask mask of bits to test the status register
Return Value:
STATUS_SUCCESS
STATUS_DEVICE_BUSY
--*/
{
NTSTATUS NTStatus;
PPSCR_REGISTERS IOBase;
ULONG Retries;
IOBase = ReaderExtension->IOBase;
NTStatus = STATUS_DEVICE_BUSY;
// wait until condition fulfilled or specified timeout expired
for ( Retries = 0; Retries < ReaderExtension->MaxRetries; Retries++) {
if (( (READ_PORT_UCHAR( &IOBase->CmdStatusReg )) == 0x01) &&
ReaderExtension->InvalidStatus) {
NTStatus = STATUS_CANCELLED;
break;
}
// test requested bits
if (( (READ_PORT_UCHAR( &IOBase->CmdStatusReg )) & Mask ) == Mask ) {
NTStatus = STATUS_SUCCESS;
break;
}
SysDelay( DELAY_PSCR_WAIT );
}
(void) READ_PORT_UCHAR( &IOBase->CmdStatusReg );
return NTStatus;
}
#pragma optimize( "", on )
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