IOHIDManager/IOHIDElement_.c

//      File: IOHIDElement_.c
//  Abstract: convieance functions for IOHIDElementGetProperty
//   Version: 2.0
//  
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//  FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND
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//  
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//  
//  Copyright (C) 2009 Apple Inc. All Rights Reserved.
//  
//*****************************************************
#pragma mark - includes & imports
//-----------------------------------------------------
 
#include "IOHIDElement_.h"
 
//*****************************************************
#pragma mark - typedef's, struct's, enums, defines, etc.
//-----------------------------------------------------
 
//*****************************************************
#pragma mark - local (static) function prototypes
//-----------------------------------------------------
 
// static Boolean IOHIDElement_GetLongProperty( IOHIDElementRef inElementRef, CFStringRef inKey, long * outValue );
// static void IOHIDElement_SetLongProperty( IOHIDElementRef inElementRef, CFStringRef inKey, long inValue );
 
//*****************************************************
#pragma mark - exported globals
//-----------------------------------------------------
 
//*****************************************************
#pragma mark - local (static) globals
//-----------------------------------------------------
 
//*****************************************************
#pragma mark - exported function implementations
//-----------------------------------------------------
 
//*************************************************************************
//
// HIDIsValidElement( inIOHIDElementRef )
//
// Purpose: validate this element
//
// Inputs:  inIOHIDElementRef   - the element
//
// Returns: Boolean         - TRUE if this is a valid element ref
//
Boolean HIDIsValidElement(IOHIDElementRef inIOHIDElementRef) {
    Boolean result = FALSE; // assume failure (pessimist!)
    if ( inIOHIDElementRef ) {
        if (                                   CFGetTypeID(inIOHIDElementRef) ==IOHIDElementGetTypeID() ) {
            result = TRUE;
        }
    }
    
    return (result);
} // HIDIsValidElement
 
//*************************************************************************
//
// IOHIDElement_GetValue( inElementRef, inIOHIDValueScaleType )
//
// Purpose: returns the current value for an element( polling )
//
// Notes:   will return 0 on error conditions which should be accounted for by application
//
// Inputs:  inElementRef    - the element
//          inIOHIDValueScaleType   - scale type ( calibrated or physical )
//
// Returns: double      - current value for element
//
double IOHIDElement_GetValue(IOHIDElementRef inElementRef, IOHIDValueScaleType inIOHIDValueScaleType) {
    long result = 0;
    IOHIDValueRef tIOHIDValueRef;
    if ( kIOReturnSuccess == IOHIDDeviceGetValue(IOHIDElementGetDevice(inElementRef), inElementRef, &tIOHIDValueRef) ) {
        result = IOHIDValueGetScaledValue(tIOHIDValueRef, inIOHIDValueScaleType);
    }
    
    return (result);
}   // IOHIDElement_GetValue
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationMin( inElementRef )
//
// Purpose: get the minimum bounds for a calibrated value for this element
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the minimum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationMin(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMinKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMaxKey), &result) ) {
            result = 0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMinKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationMin
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationMin( inElementRef, inValue )
//
// Purpose: set the minimum bounds for a calibrated value for this element
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the minimum bounds for a calibrated value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationMin(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMinKey), inValue);
}   // IOHIDElement_SetCalibrationMin
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationMax( inElementRef )
//
// Purpose: get the maximum bounds for a calibrated value for this element
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the maximum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationMax(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMaxKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMaxKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationMax
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationMax( inElementRef, inValue )
//
// Purpose: set the maximum bounds for a calibrated value for this element
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the maximum Calibration value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationMax(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationMaxKey), inValue);
}   // IOHIDElement_SetCalibrationMax
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationSaturationMin( inElementRef )
//
// Purpose: get the mininum tolerance to be used when calibrating a logical element value
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the maximum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationSaturationMin(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMinKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMinKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationSaturationMin
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationSaturationMin( inElementRef, inValue )
//
// Purpose: set the mininum tolerance to be used when calibrating a logical element value
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the maximum Calibration value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationSaturationMin(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMinKey), inValue);
}   // IOHIDElement_SetCalibrationSaturationMin
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationSaturationMax( inElementRef )
//
// Purpose: get the maximum tolerance to be used when calibrating a logical element value
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the maximum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationSaturationMax(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMaxKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMaxKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationSaturationMax
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationSaturationMax( inElementRef, inValue )
//
// Purpose: set the maximum tolerance to be used when calibrating a logical element value
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the maximum Calibration value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationSaturationMax(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationSaturationMaxKey), inValue);
}   // IOHIDElement_SetCalibrationSaturationMax
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationDeadZoneMin( inElementRef )
//
// Purpose: get the minimum bounds near the midpoint of a logical value in which the value is ignored
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the maximum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationDeadZoneMin(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMinKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMinKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationDeadZoneMin
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationDeadZoneMin( inElementRef, inValue )
//
// Purpose: set the minimum bounds near the midpoint of a logical value in which the value is ignored
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the maximum Calibration value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationDeadZoneMin(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMinKey), inValue);
}   // IOHIDElement_SetCalibrationDeadZoneMin
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationDeadZoneMax( inElementRef )
//
// Purpose: get the maximum bounds near the midpoint of a logical value in which the value is ignored
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: CFIndex - the maximum Calibration value for this element
//
 
CFIndex IOHIDElement_GetCalibrationDeadZoneMax(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMaxKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMaxKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationDeadZoneMax
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationDeadZoneMax( inElementRef, inValue )
//
// Purpose: set the maximum bounds near the midpoint of a logical value in which the value is ignored
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the maximum Calibration value for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationDeadZoneMax(IOHIDElementRef inElementRef, CFIndex inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationDeadZoneMaxKey), inValue);
}   // IOHIDElement_SetCalibrationDeadZoneMax
 
//*************************************************************************
//
// IOHIDElement_GetCalibrationGranularity( inElementRef )
//
// Purpose: get the level of detail returned for a calibrated element value
//
// Inputs:  inElementRef - the IOHIDElementRef for this element
//
// Returns: double_t - the maximum Calibration value for this element
//
 
double_t IOHIDElement_GetCalibrationGranularity(IOHIDElementRef inElementRef) {
    CFIndex result;
    if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationGranularityKey), &result) ) {
        if ( !IOHIDElement_GetLongProperty(inElementRef, CFSTR(kIOHIDElementMinKey), &result) ) {
            result = -0x7FFFFFFF;
        }
        
        IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationGranularityKey), result);
    }
    
    return (result);
}   // IOHIDElement_GetCalibrationGranularity
 
//*************************************************************************
//
// IOHIDElement_SetCalibrationGranularity( inElementRef, inValue )
//
// Purpose: set the level of detail returned for a calibrated element value
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//          inValue         - the the level of detail for this element
//
// Returns: nothing
//
 
void IOHIDElement_SetCalibrationGranularity(IOHIDElementRef inElementRef, double_t inValue) {
    IOHIDElement_SetLongProperty(inElementRef, CFSTR(kIOHIDElementCalibrationGranularityKey), inValue);
}   // IOHIDElement_SetCalibrationGranularity
 
//*************************************************************************
//
// IOHIDElement_SetupCalibration( inElementRef )
//
// Purpose: set default values for the element calibration parameters
//
// Inputs:  inElementRef    - the IOHIDElementRef for this element
//
// Returns: nothing
//
void IOHIDElement_SetupCalibration(IOHIDElementRef inIOHIDElementRef) {
    // these are the min/max values returned by IOHIDValueGetScaledValue( v, kIOHIDValueScaleTypeCalibrated );
    IOHIDElement_SetCalibrationMin( inIOHIDElementRef, IOHIDElementGetLogicalMin(inIOHIDElementRef) );
    IOHIDElement_SetCalibrationMax( inIOHIDElementRef, IOHIDElementGetLogicalMax(inIOHIDElementRef) );
    
    // this is the granularity of the values returned by IOHIDValueGetScaledValue( v, kIOHIDValueScaleTypeCalibrated );
    // for example if set to 0.1 the values returned will be multiples of 0.1 ( 0.1, 0.2, 0.3, etc. )
    IOHIDElement_SetCalibrationGranularity(inIOHIDElementRef, 0.);
    
    // these define the dead zone (like in the middel of joystick axis)
    IOHIDElement_SetCalibrationDeadZoneMin(inIOHIDElementRef, 0);
    IOHIDElement_SetCalibrationDeadZoneMax(inIOHIDElementRef, 0);
#if 1
    // get the current value of this element
    double value = IOHIDElement_GetValue(inIOHIDElementRef, kIOHIDValueScaleTypePhysical);
    // use it as our min/mas saturation
    IOHIDElement_SetCalibrationSaturationMin(inIOHIDElementRef, value);
    IOHIDElement_SetCalibrationSaturationMax(inIOHIDElementRef, value);
#else
    // calculate the middle physical value we would expect from this element
    CFIndex valueMin = IOHIDElementGetPhysicalMin(inIOHIDElementRef);
    CFIndex valueMax = IOHIDElementGetPhysicalMax(inIOHIDElementRef);
    CFIndex valueMid = (valueMin + valueMax) / 2;
    
    // use it as our min/mas saturation
    // this value determines the min/max values that have been recieved from the device element
    IOHIDElement_SetCalibrationSaturationMin(inIOHIDElementRef, valueMid);
    IOHIDElement_SetCalibrationSaturationMax(inIOHIDElementRef, valueMid);
    
    // get the current value of this element
    double value = IOHIDElement_GetValue(inIOHIDElementRef, kIOHIDValueScaleTypePhysical);
    // and use it to adjust the current saturation values if it's outside their range
    if ( value < IOHIDElement_GetCalibrationSaturationMin(inIOHIDElementRef) ) {
        IOHIDElement_SetCalibrationSaturationMin(inIOHIDElementRef, value);
    }
    if ( value > IOHIDElement_GetCalibrationSaturationMax(inIOHIDElementRef) ) {
        IOHIDElement_SetCalibrationSaturationMax(inIOHIDElementRef, value);
    }
    
#endif
}   // IOHIDElement_SetupCalibration
//*****************************************************
#pragma mark - local (static) function implementations
//-----------------------------------------------------
 
//*************************************************************************
//
// IOHIDElement_GetLongProperty( inElementRef, inKey, outValue )
//
// Purpose: convieance function to return a long property of an element
//
// Inputs:  inElementRef    - the element
//          inKey           - CFString for the key
//          outValue        - address where to store the value
// Returns: Boolean         - TRUE if successful
//          outValue        - the long property's value
//
 
Boolean IOHIDElement_GetLongProperty(IOHIDElementRef inElementRef, CFStringRef inKey, long *outValue) {
    Boolean result = FALSE;
    
    CFTypeRef tCFTypeRef = IOHIDElementGetProperty(inElementRef, inKey);
    if ( tCFTypeRef ) {
        // if this is a number
        if ( CFNumberGetTypeID() == CFGetTypeID(tCFTypeRef) ) {
            // get it's value
            result = CFNumberGetValue( (CFNumberRef) tCFTypeRef, kCFNumberSInt32Type, outValue );
        }
    }
    
    return (result);
} /* IOHIDElement_GetLongProperty */
 
//*************************************************************************
//
// IOHIDElement_SetLongProperty( inElementRef, inKey, inValue )
//
// Purpose: convieance function to set a long property of an element
//
// Inputs:  inElementRef    - the element
//          inKey           - CFString for the key
//          inValue         - the value to set it to
//
// Returns: nothing
//
 
void IOHIDElement_SetLongProperty(IOHIDElementRef inElementRef, CFStringRef inKey, long inValue) {
    CFNumberRef tCFNumberRef = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &inValue);
    if ( tCFNumberRef ) {
        IOHIDElementSetProperty(inElementRef, inKey, tCFNumberRef);
        CFRelease(tCFNumberRef);
    }
} // IOHIDElement_SetLongProperty
 
//*****************************************************