668 lines
22 KiB
C
668 lines
22 KiB
C
/*++
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Copyright (C) Microsoft Corporation, 1993 - 1999
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Module Name:
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nibble.c
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Abstract:
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This module contains the code to do nibble mode reads.
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Author:
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Anthony V. Ercolano 1-Aug-1992
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Norbert P. Kusters 22-Oct-1993
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Environment:
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Kernel mode
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Revision History :
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--*/
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#include "pch.h"
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BOOLEAN
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ParIsNibbleSupported(
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IN PDEVICE_EXTENSION Extension
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);
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BOOLEAN
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ParIsChannelizedNibbleSupported(
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IN PDEVICE_EXTENSION Extension
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);
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NTSTATUS
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ParEnterNibbleMode(
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IN PDEVICE_EXTENSION Extension,
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IN BOOLEAN DeviceIdRequest
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);
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NTSTATUS
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ParEnterChannelizedNibbleMode(
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IN PDEVICE_EXTENSION Extension,
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IN BOOLEAN DeviceIdRequest
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);
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VOID
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ParTerminateNibbleMode(
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IN PDEVICE_EXTENSION Extension
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);
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NTSTATUS
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ParNibbleModeRead(
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IN PDEVICE_EXTENSION Extension,
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IN PVOID Buffer,
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IN ULONG BufferSize,
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OUT PULONG BytesTransferred
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);
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BOOLEAN
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ParIsNibbleSupported(
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IN PDEVICE_EXTENSION Extension
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)
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/*++
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Routine Description:
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This routine determines whether or not nibble mode is suported
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by trying to negotiate when asked.
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Arguments:
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Extension - The device extension.
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Return Value:
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BOOLEAN.
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--*/
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{
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NTSTATUS Status;
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ParDump2(PARINFO, ("ParIsNibbleSupported: Start\n"));
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if (Extension->BadProtocolModes & NIBBLE) {
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ParDump2(PARINFO, ("ParIsNibbleSupported: BAD PROTOCOL Leaving\n"));
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return FALSE;
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}
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if (Extension->ProtocolModesSupported & NIBBLE) {
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ParDump2(PARINFO, ("ParIsNibbleSupported: Already Checked YES Leaving\n"));
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return TRUE;
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}
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Status = ParEnterNibbleMode (Extension, FALSE);
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ParTerminateNibbleMode (Extension);
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if (NT_SUCCESS(Status)) {
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ParDump2(PARINFO, ("ParIsNibbleSupported: SUCCESS Leaving\n"));
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Extension->ProtocolModesSupported |= NIBBLE;
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return TRUE;
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}
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ParDump2(PARINFO, ("ParIsNibbleSupported: UNSUCCESSFUL Leaving\n"));
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return FALSE;
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}
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BOOLEAN
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ParIsChannelizedNibbleSupported(
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IN PDEVICE_EXTENSION Extension
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)
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/*++
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Routine Description:
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This routine determines whether or not channelized nibble mode is suported (1284.3)
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by trying to negotiate when asked.
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Arguments:
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Extension - The device extension.
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Return Value:
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BOOLEAN.
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--*/
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{
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NTSTATUS Status;
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ParDump2(PARINFO, ("ParIsChannelizedNibbleSupported: Start\n"));
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if (Extension->BadProtocolModes & CHANNEL_NIBBLE) {
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ParDump2(PARINFO, ("ParIsChannelizedNibbleSupported: BAD PROTOCOL Leaving\n"));
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return FALSE;
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}
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if (Extension->ProtocolModesSupported & CHANNEL_NIBBLE) {
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ParDump2(PARINFO, ("ParIsChannelizedNibbleSupported: Already Checked YES Leaving\n"));
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return TRUE;
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}
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Status = ParEnterChannelizedNibbleMode (Extension, FALSE);
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ParTerminateNibbleMode (Extension);
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if (NT_SUCCESS(Status)) {
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ParDump2(PARINFO, ("ParIsChannelizedNibbleSupported: SUCCESS Leaving\n"));
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Extension->ProtocolModesSupported |= CHANNEL_NIBBLE;
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return TRUE;
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}
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ParDump2(PARINFO, ("ParIsChannelizedNibbleSupported: UNSUCCESSFUL Leaving\n"));
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return FALSE;
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}
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NTSTATUS
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ParEnterNibbleMode(
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IN PDEVICE_EXTENSION Extension,
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IN BOOLEAN DeviceIdRequest
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)
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/*++
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Routine Description:
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This routine performs 1284 negotiation with the peripheral to the
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nibble mode protocol.
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Arguments:
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Controller - Supplies the port address.
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DeviceIdRequest - Supplies whether or not this is a request for a device
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id.
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Return Value:
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STATUS_SUCCESS - Successful negotiation.
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otherwise - Unsuccessful negotiation.
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--*/
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{
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NTSTATUS Status = STATUS_SUCCESS;
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ParDump2(PARINFO, ("ParEnterNibbleMode: Start\n"));
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if ( Extension->ModeSafety == SAFE_MODE ) {
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if (DeviceIdRequest) {
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Status = IeeeEnter1284Mode (Extension, NIBBLE_EXTENSIBILITY | DEVICE_ID_REQ);
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} else {
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Status = IeeeEnter1284Mode (Extension, NIBBLE_EXTENSIBILITY);
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}
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} else {
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ParDump2(PARINFO, ("ParEnterNibbleMode: In UNSAFE_MODE.\n"));
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Extension->Connected = TRUE;
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}
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// dvdr
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if (NT_SUCCESS(Status)) {
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ParDump2(PARINFO, ("ParEnterNibbleMode: IeeeEnter1284Mode returned success\n"));
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Extension->CurrentEvent = 6;
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Extension->CurrentPhase = PHASE_NEGOTIATION;
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Extension->IsIeeeTerminateOk = TRUE;
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} else {
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ParDump2(PARINFO, ("ParEnterNibbleMode: IeeeEnter1284Mode returned unsuccessful\n"));
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ParTerminateNibbleMode ( Extension );
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Extension->CurrentPhase = PHASE_UNKNOWN;
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Extension->IsIeeeTerminateOk = FALSE;
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}
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ParDump2(PARINFO, ("ParEnterNibbleMode: Leaving with Status : %x \n", Status));
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return Status;
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}
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NTSTATUS
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ParEnterChannelizedNibbleMode(
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IN PDEVICE_EXTENSION Extension,
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IN BOOLEAN DeviceIdRequest
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)
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/*++
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Routine Description:
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This routine performs 1284 negotiation with the peripheral to the
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nibble mode protocol.
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Arguments:
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Controller - Supplies the port address.
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DeviceIdRequest - Supplies whether or not this is a request for a device
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id.
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Return Value:
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STATUS_SUCCESS - Successful negotiation.
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otherwise - Unsuccessful negotiation.
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--*/
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{
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NTSTATUS Status = STATUS_SUCCESS;
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ParDump2(PARINFO, ("ParEnterChannelizedNibbleMode: Start\n"));
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if ( Extension->ModeSafety == SAFE_MODE ) {
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if (DeviceIdRequest) {
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Status = IeeeEnter1284Mode (Extension, CHANNELIZED_EXTENSIBILITY | DEVICE_ID_REQ);
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} else {
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Status = IeeeEnter1284Mode (Extension, CHANNELIZED_EXTENSIBILITY);
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}
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} else {
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ParDump2(PARINFO, ("ParEnterChannelizedNibbleMode: In UNSAFE_MODE.\n"));
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Extension->Connected = TRUE;
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}
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// dvdr
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if (NT_SUCCESS(Status)) {
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ParDump2(PARINFO, ("ParEnterChannelizedNibbleMode: IeeeEnter1284Mode returned success\n"));
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Extension->CurrentEvent = 6;
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Extension->CurrentPhase = PHASE_NEGOTIATION;
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Extension->IsIeeeTerminateOk = TRUE;
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} else {
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ParDump2(PARINFO, ("ParEnterChannelizedNibbleMode: IeeeEnter1284Mode returned unsuccessful\n"));
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ParTerminateNibbleMode ( Extension );
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Extension->CurrentPhase = PHASE_UNKNOWN;
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Extension->IsIeeeTerminateOk = FALSE;
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}
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ParDump2(PARINFO, ("ParEnterChannelizedNibbleMode: Leaving with Status : %x \n", Status));
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return Status;
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}
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VOID
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ParTerminateNibbleMode(
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IN PDEVICE_EXTENSION Extension
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)
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/*++
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Routine Description:
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This routine terminates the interface back to compatibility mode.
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Arguments:
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Controller - Supplies the parallel port's controller address.
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Return Value:
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None.
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--*/
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{
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ParDump2(PARINFO, ("ParTerminateNibbleMode: Enter.\n"));
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if ( Extension->ModeSafety == SAFE_MODE ) {
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IeeeTerminate1284Mode (Extension);
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} else {
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ParDump2(PARINFO, ("ParTerminateNibbleMode: In UNSAFE_MODE.\n"));
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Extension->Connected = FALSE;
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}
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ParDump2(PARINFO, ("ParTerminateNibbleMode: Exit.\n"));
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}
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NTSTATUS
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ParNibbleModeRead(
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IN PDEVICE_EXTENSION Extension,
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IN PVOID Buffer,
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IN ULONG BufferSize,
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OUT PULONG BytesTransferred
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)
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/*++
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Routine Description:
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This routine performs a 1284 nibble mode read into the given
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buffer for no more than 'BufferSize' bytes.
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Arguments:
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Extension - Supplies the device extension.
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Buffer - Supplies the buffer to read into.
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BufferSize - Supplies the number of bytes in the buffer.
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BytesTransferred - Returns the number of bytes transferred.
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--*/
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{
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PUCHAR Controller;
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PUCHAR wPortDCR;
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PUCHAR wPortDSR;
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NTSTATUS Status = STATUS_SUCCESS;
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PUCHAR p = (PUCHAR)Buffer;
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UCHAR dsr, dcr;
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UCHAR nibble[2];
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ULONG i, j;
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Controller = Extension->Controller;
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wPortDCR = Controller + OFFSET_DCR;
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wPortDSR = Controller + OFFSET_DSR;
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// Read nibbles according to 1284 spec.
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ParDump2(PARENTRY,("ParNibbleModeRead: Start\n"));
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dcr = READ_PORT_UCHAR(wPortDCR);
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switch (Extension->CurrentPhase) {
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case PHASE_NEGOTIATION:
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ParDump2(PARINFO,("ParNibbleModeRead: PHASE_NEGOTIATION\n"));
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// Starting in state 6 - where do we go from here?
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// To Reverse Idle or Reverse Data Transfer Phase depending if
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// data is available.
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dsr = READ_PORT_UCHAR(wPortDSR);
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// =============== Periph State 6 ===============8
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// PeriphAck/PtrBusy = Don't Care
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// PeriphClk/PtrClk = Don't Care (should be high
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// and the nego. proc already
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// checked this)
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// nAckReverse/AckDataReq = Don't Care (should be high)
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// XFlag = Don't Care (should be low)
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// nPeriphReq/nDataAvail = High/Low (line status determines
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// which state we move to)
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Extension->CurrentEvent = 6;
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#if (0 == DVRH_USE_NIBBLE_MACROS)
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if (dsr & DSR_NOT_DATA_AVAIL)
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#else
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if (TEST_DSR(dsr, DONT_CARE, DONT_CARE, DONT_CARE, DONT_CARE, ACTIVE ))
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#endif
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{
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// Data is NOT available - go to Reverse Idle
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ParDump2(PARINFO,("ParNibbleModeRead: PHASE_REVERSE_IDLE\n"));
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// Host enters state 7 - officially in Reverse Idle now
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// Must stall for at least .5 microseconds before this state.
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KeStallExecutionProcessor(1);
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/* =============== Host State 7 Nibble Reverse Idle ===============8
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DIR = Don't Care
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IRQEN = Don't Care
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1284/SelectIn = High
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nReverseReq/ (ECP only)= Don't Care
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HostAck/HostBusy = Low (signals State 7)
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HostClk/nStrobe = High
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============================================================ */
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Extension->CurrentEvent = 7;
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#if (0 == DVRH_USE_NIBBLE_MACROS)
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dcr |= DCR_NOT_HOST_BUSY;
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#else
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dcr = UPDATE_DCR(dcr, DONT_CARE, DONT_CARE, ACTIVE, DONT_CARE, INACTIVE, ACTIVE);
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#endif
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WRITE_PORT_UCHAR(wPortDCR, dcr);
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Extension->CurrentPhase = PHASE_REVERSE_IDLE ;
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// FALL THRU TO reverse idle
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} else {
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// Data is available, go to Reverse Transfer Phase
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Extension->CurrentPhase = PHASE_REVERSE_XFER ;
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// DO NOT fall thru
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goto PhaseReverseXfer; // please save me from my sins!
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}
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case PHASE_REVERSE_IDLE:
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// Check to see if the peripheral has indicated Interrupt Phase and if so,
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// get us ready to reverse transfer.
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// See if data is available (looking for state 19)
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dsr = READ_PORT_UCHAR(Controller + OFFSET_DSR);
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if (!(dsr & DSR_NOT_DATA_AVAIL)) {
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dcr = READ_PORT_UCHAR(wPortDCR);
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// =========== Host State 20 Interrupt Phase ===========8
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// DIR = Don't Care
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// IRQEN = Don't Care
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// 1284/SelectIn = High
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// nReverseReq/ (ECP only) = Don't Care
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// HostAck/HostBusy = High (Signals state 20)
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// HostClk/nStrobe = High
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//
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// Data is available, get us to Reverse Transfer Phase
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Extension->CurrentEvent = 20;
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dcr = UPDATE_DCR(dcr, DONT_CARE, DONT_CARE, ACTIVE, DONT_CARE, ACTIVE, ACTIVE);
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WRITE_PORT_UCHAR(wPortDCR, dcr);
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// =============== Periph State 21 HBDA ===============8
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// PeriphAck/PtrBusy = Don't Care
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// PeriphClk/PtrClk = Don't Care (should be high)
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// nAckReverse/AckDataReq = low (signals state 21)
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// XFlag = Don't Care (should be low)
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// nPeriphReq/nDataAvail = Don't Care (should be low)
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Extension->CurrentEvent = 21;
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if (CHECK_DSR(Controller,
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DONT_CARE, DONT_CARE, INACTIVE,
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DONT_CARE, DONT_CARE,
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IEEE_MAXTIME_TL)) {
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// Got state 21
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// Let's jump to Reverse Xfer and get the data
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Extension->CurrentPhase = PHASE_REVERSE_XFER;
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goto PhaseReverseXfer;
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} else {
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// Timeout on state 21
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Extension->IsIeeeTerminateOk = TRUE;
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Status = STATUS_IO_DEVICE_ERROR;
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Extension->CurrentPhase = PHASE_UNKNOWN;
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ParDump2(PARERRORS, ("ParNibbleModeRead:Failed State 21: Controller %x dcr %x\n",
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Controller, dcr));
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// NOTE: Don't ASSERT Here. An Assert here can bite you if you are in
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// Nibble Rev and you device is off/offline.
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// dvrh 2/25/97
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goto NibbleReadExit;
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}
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} else {
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// Data is NOT available - do nothing
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// The device doesn't report any data, it still looks like it is
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// in ReverseIdle. Just to make sure it hasn't powered off or somehow
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// jumped out of Nibble mode, test also for AckDataReq high and XFlag low
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// and nDataAvaul high.
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Extension->CurrentEvent = 18;
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dsr = READ_PORT_UCHAR(Controller + OFFSET_DSR);
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if(( dsr & DSR_NIBBLE_VALIDATION )== DSR_NIBBLE_TEST_RESULT ) {
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Extension->CurrentPhase = PHASE_REVERSE_IDLE ;
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} else {
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#if DVRH_BUS_RESET_ON_ERROR
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BusReset(wPortDCR); // Pass in the dcr address
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#endif
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// Appears we failed state 19.
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Extension->IsIeeeTerminateOk = TRUE;
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Status = STATUS_IO_DEVICE_ERROR;
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Extension->CurrentPhase = PHASE_UNKNOWN;
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ParDump2(PARERRORS, ("ParNibbleModeRead:Failed State 19: Controller %x dcr %x\n",
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Controller, dcr));
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}
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goto NibbleReadExit;
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}
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PhaseReverseXfer:
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case PHASE_REVERSE_XFER:
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ParDump2(PARINFO,("ParNibbleModeRead:PHASE_REVERSE_IDLE\n"));
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for (i = 0; i < BufferSize; i++) {
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for (j = 0; j < 2; j++) {
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// Host enters state 7 or 12 depending if nibble 1 or 2
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// StoreControl (Controller, HDReady);
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dcr |= DCR_NOT_HOST_BUSY;
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WRITE_PORT_UCHAR(wPortDCR, dcr);
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// =============== Periph State 9 ===============8
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// PeriphAck/PtrBusy = Don't Care (Bit 3 of Nibble)
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// PeriphClk/PtrClk = low (signals state 9)
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// nAckReverse/AckDataReq = Don't Care (Bit 2 of Nibble)
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// XFlag = Don't Care (Bit 1 of Nibble)
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// nPeriphReq/nDataAvail = Don't Care (Bit 0 of Nibble)
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Extension->CurrentEvent = 9;
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if (!CHECK_DSR(Controller,
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DONT_CARE, INACTIVE, DONT_CARE,
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DONT_CARE, DONT_CARE,
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IEEE_MAXTIME_TL)) {
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// Time out.
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// Bad things happened - timed out on this state,
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// Mark Status as bad and let our mgr kill current mode.
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Extension->IsIeeeTerminateOk = FALSE;
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Status = STATUS_IO_DEVICE_ERROR;
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ParDump2(PARERRORS, ("ParNibbleModeRead:Failed State 9: Controller %x dcr %x\n",
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Controller, dcr));
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Extension->CurrentPhase = PHASE_UNKNOWN;
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goto NibbleReadExit;
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}
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// Read Nibble
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nibble[j] = READ_PORT_UCHAR(wPortDSR);
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/* ============== Host State 10 Nibble Read ===============8
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DIR = Don't Care
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IRQEN = Don't Care
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1284/SelectIn = High
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HostAck/HostBusy = High (signals State 10)
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HostClk/nStrobe = High
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============================================================ */
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Extension->CurrentEvent = 10;
|
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dcr &= ~DCR_NOT_HOST_BUSY;
|
||
WRITE_PORT_UCHAR(wPortDCR, dcr);
|
||
|
||
// =============== Periph State 11 ===============8
|
||
// PeriphAck/PtrBusy = Don't Care (Bit 3 of Nibble)
|
||
// PeriphClk/PtrClk = High (signals state 11)
|
||
// nAckReverse/AckDataReq = Don't Care (Bit 2 of Nibble)
|
||
// XFlag = Don't Care (Bit 1 of Nibble)
|
||
// nPeriphReq/nDataAvail = Don't Care (Bit 0 of Nibble)
|
||
Extension->CurrentEvent = 11;
|
||
if (!CHECK_DSR(Controller,
|
||
DONT_CARE, ACTIVE, DONT_CARE,
|
||
DONT_CARE, DONT_CARE,
|
||
IEEE_MAXTIME_TL)) {
|
||
// Time out.
|
||
// Bad things happened - timed out on this state,
|
||
// Mark Status as bad and let our mgr kill current mode.
|
||
Status = STATUS_IO_DEVICE_ERROR;
|
||
Extension->IsIeeeTerminateOk = FALSE;
|
||
ParDump2(PARERRORS, ("ParNibbleModeRead:Failed State 11: Controller %x dcr %x\n",
|
||
Controller, dcr));
|
||
Extension->CurrentPhase = PHASE_UNKNOWN;
|
||
goto NibbleReadExit;
|
||
}
|
||
}
|
||
|
||
// Read two nibbles - make them into one byte.
|
||
|
||
p[i] = (((nibble[0]&0x38)>>3)&0x07) |
|
||
((nibble[0]&0x80) ? 0x00 : 0x08);
|
||
p[i] |= (((nibble[1]&0x38)<<1)&0x70) |
|
||
((nibble[1]&0x80) ? 0x00 : 0x80);
|
||
|
||
ParDump2(PARINFO,("ParNibbleModeRead:%x:%c\n", p[i], p[i]));
|
||
|
||
// At this point, we've either received the number of bytes we
|
||
// were looking for, or the peripheral has no more data to
|
||
// send, or there was an error of some sort (of course, in the
|
||
// error case we shouldn't get to this comment). Set the
|
||
// phase to indicate reverse idle if no data available or
|
||
// reverse data transfer if there's some waiting for us
|
||
// to get next time.
|
||
|
||
dsr = READ_PORT_UCHAR(wPortDSR);
|
||
|
||
if (dsr & DSR_NOT_DATA_AVAIL) {
|
||
|
||
// Data is NOT available - go to Reverse Idle
|
||
// Really we are going to HBDNA, but if we set
|
||
// current phase to reverse idle, the next time
|
||
// we get into this function all we have to do
|
||
// is set hostbusy low to indicate idle and
|
||
// we have infinite time to do that.
|
||
// Break out of the loop so we don't try to read
|
||
// data that isn't there.
|
||
// NOTE - this is a successful case even if we
|
||
// didn't read all that the caller requested
|
||
Extension->CurrentPhase = PHASE_REVERSE_IDLE ;
|
||
i++; // account for this last byte transferred
|
||
break;
|
||
|
||
} else {
|
||
// Data is available, go to (remain in ) Reverse Transfer Phase
|
||
Extension->CurrentPhase = PHASE_REVERSE_XFER ;
|
||
}
|
||
} // end for i loop
|
||
|
||
*BytesTransferred = i;
|
||
// DON'T FALL THRU THIS ONE
|
||
break;
|
||
|
||
default:
|
||
// I'm gonna mark this as false. There is not a correct answer here.
|
||
// The peripheral and the host are out of sync. I'm gonna reset myself
|
||
// and the peripheral.
|
||
Extension->IsIeeeTerminateOk = FALSE;
|
||
Status = STATUS_IO_DEVICE_ERROR;
|
||
Extension->CurrentPhase = PHASE_UNKNOWN ;
|
||
|
||
ParDump2(PARERRORS, ("ParNibbleModeRead:Failed State 9: Unknown Phase. Controller %x dcr %x\n",
|
||
Controller, dcr));
|
||
ParDump2(PARERRORS, ( "ParNibbleModeRead: You're hosed man.\n" ));
|
||
ParDump2(PARERRORS, ( "ParNibbleModeRead: If you are here, you've got a bug somewhere else.\n" ));
|
||
ParDump2(PARERRORS, ( "ParNibbleModeRead: Go fix it!\n" ));
|
||
goto NibbleReadExit;
|
||
break;
|
||
} // end switch
|
||
|
||
NibbleReadExit:
|
||
|
||
ParDump2(PARINFO,("ParNibbleModeRead:PHASE_REVERSE_IDLE\n"));
|
||
|
||
if( Extension->CurrentPhase == PHASE_REVERSE_IDLE ) {
|
||
// Host enters state 7 - officially in Reverse Idle now
|
||
dcr |= DCR_NOT_HOST_BUSY;
|
||
|
||
WRITE_PORT_UCHAR (wPortDCR, dcr);
|
||
}
|
||
|
||
ParDump2(PAREXIT,("ParNibbleModeRead:End [%d] bytes read = %d\n",
|
||
NT_SUCCESS(Status), *BytesTransferred));
|
||
Extension->log.NibbleReadCount += *BytesTransferred;
|
||
return Status;
|
||
}
|
||
|