mirror of https://github.com/tongzx/nt5src
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
545 lines
22 KiB
545 lines
22 KiB
/*---
|
|
Copyright (c) 1998 - 1999 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
poll.c
|
|
|
|
Abstract: This module contains the routines to poll an analog gameport device
|
|
|
|
Environment:
|
|
|
|
Kernel mode
|
|
|
|
@@BEGIN_DDKSPLIT
|
|
Author:
|
|
|
|
Eliyas Yakub (Mar, 11, 1997)
|
|
|
|
Revision History:
|
|
|
|
Updated by Eliyas on Feb 5 1998
|
|
MarcAnd 02-Jul-98 Quick tidy for DDK
|
|
MarcAnd 04-Oct-98 Re-org
|
|
|
|
@@END_DDKSPLIT
|
|
|
|
--*/
|
|
|
|
#include "hidgame.h"
|
|
|
|
|
|
/*****************************************************************************
|
|
*
|
|
* @doc EXTERNAL
|
|
*
|
|
* @func NTSTATUS | HidAnalogPoll |
|
|
*
|
|
* Polling routine for analog joysticks.
|
|
* <nl>Polls the analog device for position and button information.
|
|
* The position information in analog devices is conveyed by the
|
|
* duration of a pulse width. Each axis occupies one bit position.
|
|
* The read operation is started by writing a value to the joystick
|
|
* io address. Immediately thereafter we begin examing the values
|
|
* returned and the elapsed time.
|
|
*
|
|
* This sort of device has a few limitations:
|
|
*
|
|
* First, button information is not latched by the device, so if a
|
|
* button press which occurrs in between polls it will be lost.
|
|
* There is really no way to prevent this short of devoting
|
|
* the entire cpu to polling. In reality this does not cause a problem.
|
|
*
|
|
* Second, since it is necessary to measure the duration of the axis pulse,
|
|
* the most accurate results would be obtained using the smallest possible
|
|
* sense loop and no interruptions of this loop.
|
|
* The typical range of pulse lengths is from around 10 uSecs to 1500 uSecs
|
|
* but depending on the joystick and gameport, this could extend to at least
|
|
* 8000 uSecs. Keeping interrupts disabled for this length of time causes
|
|
* many problems, like modems losing connections to sound break ups.
|
|
*
|
|
* Third, because each iteration of the poll loop requires an port read, the
|
|
* speed of the loop is largely constrained by the speed of the IO bus.
|
|
* This also means that when there is contention for the IO bus, the loop
|
|
* will be slowed down. IO contention is usually caused by DMAs (or FDMAs)
|
|
* which result in a significant slow down.
|
|
*
|
|
* Forth, because of the previous two problems, the poll loop may be slowed
|
|
* down or interrupted at any time so an external time source is needed to
|
|
* measure the pulse width for each axis. The only cross-platform high
|
|
* resolution timer is the read with KeQueryPerformanceCounter.
|
|
* Unfortunately the implementation of this often uses a 1.18MHz 8253 timer
|
|
* which requires 3 IO accesses to read, compounding the third problem and
|
|
* even then, the result may need to be reread if the counters were in the
|
|
* wrong state. Current CPUs have on board counters that can be used to
|
|
* provide very accurate timing and more recent HAL implementations tend to
|
|
* use these to implement KeQueryPerformanceCounter so this will be a problem
|
|
* on less systems as time goes on. In the majority of cases, a poor
|
|
* KeQueryPerformanceCounter implementation is made irrelevant by testing
|
|
* for the availability of a CPU time stamp counter on Intel architechtures
|
|
* and using it directly if it is available.
|
|
*
|
|
* The algorithm implemented here is not the most obvious but works as
|
|
* follows:
|
|
*
|
|
* Once started, the axes read a value of one until the completion of their
|
|
* pulse. The axes are the four lower bits in the byte read from the port.
|
|
* The state of the axes in each iteration of the poll loop is therefore
|
|
* represented as a value between 0 and 15. The important time for each
|
|
* axis is the time at which it changes from 1 to 0. This is done by using
|
|
* the value representing the state of the axes to index an array into which
|
|
* time values are stored. For each axis, the duration of its pulse width is
|
|
* the latest time stored in the array at an index with the bit for that axis
|
|
* set. However since interrupts can occur at any time, it is not possible
|
|
* to simultaneously read the port value and record that time in an atomic
|
|
* operation the in each iteration, the current time is stored in two arrays,
|
|
* one using the index before the time was recorded and the other using the
|
|
* index after the time was recorded.
|
|
* Once all the axes being monitored have become 0, or a timeout value is
|
|
* reached, the data left in the arrays is analysed to find the best
|
|
* estimate for the transition time for each axis. If the times before and
|
|
* after the transition differ by too much, it is judged that an interrupt
|
|
* must have occured so the last known good axis value is returned unless
|
|
* that falls outside the range in which it is known that the transition
|
|
* occured.
|
|
*
|
|
* This routine cannot be pageable as HID can make reads at dispatch-level.
|
|
*
|
|
* @parm IN PDEVICE_EXTENSION | DeviceExtension |
|
|
*
|
|
* Pointer to the device extension.
|
|
*
|
|
* @parm IN UCHAR | resisitiveInputMask |
|
|
*
|
|
* Mask that describes the axes lines that are to be polled
|
|
*
|
|
* @parm IN BOOLEAN | fApproximate |
|
|
*
|
|
* Boolean value indicating if it is OK to approximate some
|
|
* value of the current axis state with the last axis state
|
|
* if polling was not successful (we took an interrput during polling)
|
|
*
|
|
* @parm IN OUT ULONG | Axis[MAX_AXES] |
|
|
*
|
|
* The state of the axes. On entry the last axis state is passed
|
|
* into this routine. If the fApproximate flag is turned on, we can
|
|
* make use of the last axis state to "guess" the current axis state.
|
|
*
|
|
* @parm OUT UCHAR | Button[PORT_BUTTONS]|
|
|
*
|
|
* Receives the state of the buttons. 0x0 specifies the button is not
|
|
* pressed and 0x1 indicates an armed button state.
|
|
*
|
|
* @rvalue STATUS_SUCCESS | success
|
|
* @rvalue STATUS_DEVICE_NOT_CONNECTED | Device Failed to Quiesce
|
|
* ( not connected ) This is a failure code.
|
|
* @rvalue STATUS_TIMEOUT | Could not determine exact transition time for
|
|
* one or more axis. This is a success code.
|
|
*
|
|
*****************************************************************************/
|
|
/*
|
|
* Tell a compiler that we "a" won't use any aliasing and "t" want fast code
|
|
*/
|
|
#pragma optimize( "at", on )
|
|
|
|
/*
|
|
* Disable warning for variable used before set as it is hard for a compiler
|
|
* to see that TimeNow is always initialized before it is used.
|
|
*/
|
|
#pragma warning( disable:4701 )
|
|
|
|
NTSTATUS INTERNAL
|
|
HGM_AnalogPoll
|
|
(
|
|
IN PDEVICE_EXTENSION DeviceExtension,
|
|
IN UCHAR resistiveInputMask,
|
|
IN BOOLEAN fApproximate,
|
|
IN OUT ULONG Axis[MAX_AXES],
|
|
OUT UCHAR Button[PORT_BUTTONS]
|
|
)
|
|
|
|
{
|
|
ULONG BeforeTimes[MAX_AXES*MAX_AXES];
|
|
ULONG AfterTimes[MAX_AXES*MAX_AXES];
|
|
ULONGLONG CounterFreq;
|
|
PUCHAR GameContext;
|
|
NTSTATUS ntStatus = STATUS_SUCCESS;
|
|
|
|
|
|
/*
|
|
* To improve compiler optimization, we cast the ReadAccessor function to
|
|
* return a ULONG instead of a UCHAR. This means that the result must
|
|
* always be masked before use but this would be done anyway to remove
|
|
* the parts of the UCHAR we are not interested in.
|
|
*/
|
|
typedef ULONG (*PHIDGAME_READPORT) ( PVOID GameContext );
|
|
|
|
PHIDGAME_READPORT ReadPort;
|
|
ULONG portLast, portMask;
|
|
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_FENTRY, \
|
|
("HGM_AnalogPoll DeviceExtension=0x%x, resistiveInputMask=0x%x",\
|
|
DeviceExtension, resistiveInputMask ));
|
|
|
|
|
|
portMask = (ULONG)(resistiveInputMask & 0xf);
|
|
|
|
/*
|
|
* Initialize Times to recognizable value
|
|
*/
|
|
memset( (PVOID)BeforeTimes, 0, sizeof( BeforeTimes ) );
|
|
memset( (PVOID)AfterTimes, 0, sizeof( AfterTimes ) );
|
|
|
|
/*
|
|
* Find where our port and data area are, and related parameters
|
|
*/
|
|
GameContext = DeviceExtension->GameContext;
|
|
ReadPort = (PHIDGAME_READPORT)(*DeviceExtension->ReadAccessor);
|
|
|
|
/*
|
|
* get the buttons (not forgetting that the top 3 bytes are garbage)
|
|
*/
|
|
portLast = ReadPort(GameContext);
|
|
Button[0] = (UCHAR)(( portLast & 0x10 ) == 0x0);
|
|
Button[1] = (UCHAR)(( portLast & 0x20 ) == 0x0);
|
|
Button[2] = (UCHAR)(( portLast & 0x40 ) == 0x0);
|
|
Button[3] = (UCHAR)(( portLast & 0x80 ) == 0x0);
|
|
|
|
portLast = portMask;
|
|
|
|
/*
|
|
* Start the pots
|
|
* (any debug output from here until the completion of the
|
|
* while( portLast ) loop will destroy the axis data)
|
|
*/
|
|
(*DeviceExtension->WriteAccessor)(GameContext, JOY_START_TIMERS);
|
|
|
|
/*
|
|
* Keep reading until all the pots we care about are zero or we time out
|
|
*/
|
|
|
|
{
|
|
ULONG TimeNow;
|
|
ULONG TimeStart;
|
|
ULONG TimeOut = DeviceExtension->ScaledTimeout/Global.CounterScale;
|
|
ULONG portVal = portMask;
|
|
|
|
TimeStart = Global.ReadCounter(NULL).LowPart;
|
|
|
|
while( portLast )
|
|
{
|
|
TimeNow = Global.ReadCounter(NULL).LowPart - TimeStart;
|
|
AfterTimes[portLast] = TimeNow;
|
|
portLast = portVal;
|
|
portVal = ReadPort(GameContext) & portMask;
|
|
BeforeTimes[portVal] = TimeNow;
|
|
|
|
if( TimeNow >= TimeOut ) break;
|
|
}
|
|
|
|
if( portLast && ( TimeNow >= TimeOut ) )
|
|
{
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE, \
|
|
("HGM_AnalogPoll: TimeNow: 0x%08x TimeOut: 0x%08x", TimeNow, TimeOut ) );
|
|
}
|
|
}
|
|
|
|
{
|
|
LONG axisIdx;
|
|
|
|
for( axisIdx = 3; axisIdx>=0; axisIdx-- )
|
|
{
|
|
ULONG axisMask;
|
|
|
|
axisMask = 1 << axisIdx;
|
|
if( axisMask & portMask )
|
|
{
|
|
if( axisMask & portLast )
|
|
{
|
|
/*
|
|
* Whether or not a hit was taken, this axis did not
|
|
* quiesce. So update the axis time so that next poll
|
|
* the last value will be a timeout in case a hit is
|
|
* taken over both the transition and the timeout.
|
|
*/
|
|
Axis[axisIdx] = AXIS_TIMEOUT;
|
|
ntStatus = STATUS_DEVICE_NOT_CONNECTED;
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_WARN, \
|
|
("HGM_AnalogPoll: axis %x still set at timeout", axisMask ) );
|
|
}
|
|
else
|
|
{
|
|
ULONG timeIdx;
|
|
ULONG beforeThresholdTime;
|
|
ULONG afterThresholdTime;
|
|
ULONG delta;
|
|
|
|
afterThresholdTime = beforeThresholdTime = 0;
|
|
for( timeIdx = axisMask; timeIdx<= portMask; timeIdx=(timeIdx+1) | axisMask )
|
|
{
|
|
if( BeforeTimes[timeIdx] > beforeThresholdTime )
|
|
{
|
|
beforeThresholdTime = BeforeTimes[timeIdx];
|
|
afterThresholdTime = AfterTimes[timeIdx];
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Convert the CPU specific timing values into 'wall clock'
|
|
* values so that they can be compared with the previous
|
|
* poll values and so that the range will be dependent on
|
|
* the gamecard/joystick characteristics, not the CPU
|
|
* and counter implementation.
|
|
* Use a ULONGLONG temp to avoid overflow.
|
|
*/
|
|
{
|
|
ULONGLONG u64Temp;
|
|
|
|
u64Temp = beforeThresholdTime * Global.CounterScale;
|
|
beforeThresholdTime = (ULONG)(u64Temp >> SCALE_SHIFT);
|
|
u64Temp = afterThresholdTime * Global.CounterScale;
|
|
afterThresholdTime = (ULONG)(u64Temp >> SCALE_SHIFT);
|
|
}
|
|
|
|
delta = afterThresholdTime - beforeThresholdTime;
|
|
if( delta > DeviceExtension->ScaledThreshold )
|
|
{
|
|
/*
|
|
* We took an unacceptable hit so only change the value
|
|
* if we know the last value is no longer correct
|
|
* Since the real time is somewhere between the before and
|
|
* after, take the value closer to the last value.
|
|
*/
|
|
if( fApproximate )
|
|
{
|
|
/*
|
|
* Be careful not to turn a failure into a success
|
|
*/
|
|
if( NT_SUCCESS(ntStatus) )
|
|
{
|
|
ntStatus = STATUS_TIMEOUT;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
ntStatus = STATUS_DEVICE_NOT_CONNECTED;
|
|
}
|
|
|
|
if( Axis[axisIdx] >= AXIS_FULL_SCALE )
|
|
{
|
|
/*
|
|
* The previous poll was a timeout
|
|
*/
|
|
if( afterThresholdTime < AXIS_FULL_SCALE )
|
|
{
|
|
/*
|
|
* This poll is not a timeout so split the
|
|
* difference since there is nothing else
|
|
* to use for an estimate.
|
|
* Since these values are scaled, it would
|
|
* be perfectly legitimate for their sum to
|
|
* be greater than 32 bits.
|
|
*/
|
|
Axis[axisIdx] = (beforeThresholdTime>>1)
|
|
+ (afterThresholdTime>>1);
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:Axis=%d, using glitch average %04x",\
|
|
axisIdx, Axis[axisIdx] ) ) ;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Since the previous poll was a timeout and
|
|
* there is no evidence that this is not, call
|
|
* this a timeout.
|
|
*/
|
|
ntStatus = STATUS_DEVICE_NOT_CONNECTED;
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:Axis=%d, repeating timeout on glitch",\
|
|
axisIdx ) ) ;
|
|
}
|
|
}
|
|
else if( beforeThresholdTime > Axis[axisIdx] )
|
|
{
|
|
Axis[axisIdx] = beforeThresholdTime;
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:Axis=%d, using smaller glitch limit %04x",\
|
|
axisIdx, Axis[axisIdx] ) ) ;
|
|
}
|
|
else if( afterThresholdTime < Axis[axisIdx] )
|
|
{
|
|
Axis[axisIdx] = afterThresholdTime;
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:Axis=%d, using larger glitch limit %04x",\
|
|
axisIdx, Axis[axisIdx] ) ) ;
|
|
}
|
|
else
|
|
{
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:Axis=%d, repeating previous on glitch %04x",\
|
|
axisIdx, Axis[axisIdx] ) ) ;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( (delta <<= 1) < DeviceExtension->ScaledThreshold )
|
|
{
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll: Updating ScaledThreshold from %d to %d",\
|
|
DeviceExtension->ScaledThreshold, delta ) ) ;
|
|
|
|
/*
|
|
* Fastest change yet, update
|
|
*/
|
|
DeviceExtension->ScaledThreshold = delta;
|
|
}
|
|
|
|
/*
|
|
* It is possible that afterThresholdTime is greater
|
|
* than the timeout limit but since the purpose of
|
|
* the timeout is to prevent excessive sampling of
|
|
* the gameport, the success or failure of an
|
|
* uninterrupted poll around this limit is not
|
|
* important.
|
|
* Since these values are scaled, it would be
|
|
* perfectly legitimate for their sum to be greater
|
|
* than 32 bits and the 1 bit of lost resolution is
|
|
* utterly negligable.
|
|
*/
|
|
Axis[axisIdx] = (beforeThresholdTime>>1)
|
|
+ (afterThresholdTime>>1);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
HGM_DBGPRINT( FILE_POLL | HGM_BABBLE2, \
|
|
("HGM_AnalogPoll:X=%d, Y=%d, R=%d, Z=%d Buttons=%d,%d,%d,%d",\
|
|
Axis[0], Axis[1], Axis[2], Axis[3],\
|
|
Button[0],Button[1],Button[2],Button[3] ) ) ;
|
|
|
|
HGM_EXITPROC(FILE_POLL|HGM_FEXIT, "HGM_AnalogPoll", ntStatus);
|
|
|
|
return ntStatus;
|
|
} /* HGM_AnalogPoll */
|
|
#pragma warning( default:4701 )
|
|
#pragma optimize( "", on )
|
|
|
|
|
|
|
|
|
|
/*****************************************************************************
|
|
*
|
|
* @doc EXTERNAL
|
|
*
|
|
* @func NTSTATUS | HGM_UpdateLatestPollData |
|
|
*
|
|
* Do whatever polling is required and possible to update the
|
|
* LastGoodAxis and LastGoodButton arrays in the DeviceExtension.
|
|
* Handles synchronization and non-fatal errors.
|
|
* <nl>This routine cannot be pageable as HID can make reads at
|
|
* dispatch-level.
|
|
*
|
|
* @parm IN OUT PDEVICE_EXTENSION | DeviceExtension |
|
|
*
|
|
* Pointer to the device extension containing the data to be updated
|
|
* and the functions and to use.
|
|
*
|
|
* @rvalue STATUS_SUCCESS | success
|
|
* @rvalue STATUS_DEVICE_CONFIGURATION_ERROR | Invalid configuration specified
|
|
*
|
|
*****************************************************************************/
|
|
#define APPROXIMATE_FAILS TRUE
|
|
|
|
NTSTATUS
|
|
HGM_UpdateLatestPollData
|
|
(
|
|
IN OUT PDEVICE_EXTENSION DeviceExtension
|
|
)
|
|
{
|
|
NTSTATUS ntStatus;
|
|
KIRQL oldIrql;
|
|
LONG axisIdx;
|
|
|
|
/*
|
|
* Acquire the global spinlock
|
|
* Read / Writes are made at dispatch level.
|
|
*/
|
|
KeAcquireSpinLock(&Global.SpinLock, &oldIrql );
|
|
|
|
/*
|
|
* First gain exclusive access to the hardware
|
|
*/
|
|
ntStatus = (*DeviceExtension->AcquirePort)( DeviceExtension->PortContext );
|
|
if( NT_SUCCESS(ntStatus) )
|
|
{
|
|
/*
|
|
* If it's available, let the hardware do the work
|
|
*/
|
|
if( DeviceExtension->ReadAccessorDigital )
|
|
{
|
|
ntStatus = (*DeviceExtension->ReadAccessorDigital)(DeviceExtension->GameContext,
|
|
DeviceExtension->resistiveInputMask,
|
|
APPROXIMATE_FAILS,
|
|
&DeviceExtension->LastGoodAxis[0],
|
|
&DeviceExtension->LastGoodButton[0]);
|
|
}
|
|
else
|
|
{
|
|
ntStatus = HGM_AnalogPoll(DeviceExtension,
|
|
DeviceExtension->resistiveInputMask,
|
|
APPROXIMATE_FAILS,
|
|
&DeviceExtension->LastGoodAxis[0],
|
|
&DeviceExtension->LastGoodButton[0]);
|
|
}
|
|
|
|
/*
|
|
* Either way, release the hardware ASAP
|
|
*/
|
|
(*DeviceExtension->ReleasePort)( DeviceExtension->PortContext );
|
|
|
|
}
|
|
|
|
/*
|
|
* Release the global spinlock and return to previous IRQL
|
|
*/
|
|
KeReleaseSpinLock(&Global.SpinLock, oldIrql);
|
|
|
|
if( ( ntStatus == STATUS_DEVICE_BUSY ) && APPROXIMATE_FAILS )
|
|
{
|
|
/*
|
|
* Clashed trying to access the gameport. So work with the same
|
|
* data as last time unless all failures must be reported or the
|
|
* last data was a failure for these axes.
|
|
*/
|
|
for( axisIdx=3; axisIdx>=0; axisIdx-- )
|
|
{
|
|
if( ( ( 1 << axisIdx ) & DeviceExtension->resistiveInputMask )
|
|
&&( DeviceExtension->LastGoodAxis[axisIdx]
|
|
>= DeviceExtension->ScaledTimeout ) )
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
if( axisIdx<0 )
|
|
{
|
|
ntStatus = STATUS_TIMEOUT;
|
|
}
|
|
}
|
|
|
|
|
|
if( !NT_SUCCESS( ntStatus ) )
|
|
{
|
|
HGM_DBGPRINT(FILE_IOCTL | HGM_WARN,\
|
|
("HGM_UpdateLatestPollData Failed 0x%x", ntStatus));
|
|
}
|
|
|
|
return( ntStatus );
|
|
} /* HGM_UpdateLatestPollData */
|