#include <sys/cdefs.h>

__BEGIN_DECLS
#include <kern/thread_call.h>
__END_DECLS

#include "AppleUSBAudioLevelControl.h"
#include "AppleUSBAudioCommon.h"
#include "AppleUSBAudioDevice.h"

#include <IOKit/audio/IOAudioTypes.h>
#include <IOKit/audio/IOAudioDefines.h>
#include <IOKit/usb/USB.h>
#include <IOKit/usb/IOUSBInterface.h>
#include <IOKit/IOLib.h>

#include <libkern/OSByteOrder.h>

#define super IOAudioLevelControl

OSDefineMetaClassAndStructors(AppleUSBAudioLevelControl, IOAudioLevelControl)

AppleUSBAudioLevelControl *AppleUSBAudioLevelControl::create (UInt8 theUnitID, UInt8 theInterfaceNumber, UInt8 theControlSelector, UInt8 theChannelNumber, USBDeviceRequest theUSBDeviceRequest, void *theCallerRefCon, UInt32 subType, UInt32 usage) {
    AppleUSBAudioLevelControl *			control;

    debug8IOLog ("+AppleUSBAudioLevelControl::create (%d, %d, %d, %d, %p, %lX, %lX)\n", theUnitID, theInterfaceNumber, theControlSelector, theChannelNumber, theUSBDeviceRequest, subType, usage);
    control = new AppleUSBAudioLevelControl;
    FailIf (NULL == control, Exit);

    if (FALSE == control->init (theUnitID, theInterfaceNumber, theControlSelector, theChannelNumber, theUSBDeviceRequest, theCallerRefCon, subType, usage)) {
        control->release ();
        control = NULL;
    }

Exit:
    debug8IOLog ("-AppleUSBAudioLevelControl::create(%d, %d, %d, %d, %p, %lX, %lX)\n", theUnitID, theInterfaceNumber, theControlSelector, theChannelNumber, theUSBDeviceRequest, subType, usage);
    return control;
}

bool AppleUSBAudioLevelControl::init (UInt8 theUnitID, UInt8 theInterfaceNumber, UInt8 theControlSelector, UInt8 theChannelNumber, USBDeviceRequest theUSBDeviceRequest, void *theCallerRefCon, UInt32 subType, UInt32 usage, OSDictionary *properties) {
	const char *				channelName = NULL;
	SInt16						currentValue;
	SInt16						deviceMin;
	SInt16						deviceMax;
	IOFixed						deviceMinDB;
	IOFixed						deviceMaxDB;
	IOFixed						resolutionDB;
	IOReturn					ret;
	Boolean						result;

	debug8IOLog ("+AppleUSBAudioLevelControl[%p]::init (%d, %d, %d, %d, %p, %p)\n", this, theUnitID, theInterfaceNumber, theControlSelector, theChannelNumber, theUSBDeviceRequest, properties);
	result = FALSE;
	FailIf (NULL == theUSBDeviceRequest, Exit);
	FailIf (VOLUME_CONTROL != theControlSelector, Exit);	 // Only supports volume control for now - add more later

	setValueThreadCall = thread_call_allocate ((thread_call_func_t)updateValueCallback, this);
	FailIf (NULL == setValueThreadCall, Exit);

	unitID = theUnitID;
	interfaceNumber = theInterfaceNumber;
	controlSelector = theControlSelector;
	channelNumber = theChannelNumber;
	callerRefCon = theCallerRefCon;
	usbDeviceRequest = theUSBDeviceRequest;

	switch (channelNumber) {
		case kIOAudioControlChannelIDAll:
			channelName = kIOAudioControlChannelNameAll;
			break;
		case kIOAudioControlChannelIDDefaultLeft:
			channelName = kIOAudioControlChannelNameLeft;
			break;
		case kIOAudioControlChannelIDDefaultRight:
			channelName = kIOAudioControlChannelNameRight;
			break;
		case 0xff:
			debugIOLog ("++AppleUSBAudioLevelControl: Does not support channel number 0xff.\n");
			return FALSE;
		default:
			channelName = "Unknown";
			break;
	}

	currentValue = GetCurVolume (interfaceNumber, channelNumber, &ret);
    FailIf (kIOReturnSuccess != ret, Exit);
	debug3IOLog ("channelNumber %d, currentValue = 0x%X, ", channelNumber, currentValue);
	volRes = GetVolumeResolution (interfaceNumber, channelNumber, &ret);
    FailIf (kIOReturnSuccess != ret, Exit);
	debug2IOLog ("vol res = %d, ", volRes);
	deviceMin = GetMinVolume (interfaceNumber, channelNumber, &ret);
    FailIf (kIOReturnSuccess != ret, Exit);
	debug2IOLog ("deviceMin = 0x%X, ", deviceMin);
	deviceMax = GetMaxVolume (interfaceNumber, channelNumber, &ret);
    FailIf (kIOReturnSuccess != ret, Exit);
	debug2IOLog ("deviceMax = 0x%X\n", deviceMax);

	// Having the device say that it does -infinity dB messes up our math, so set the min at -127.9961dB instead.
	if ((SInt16)0x8000 == deviceMin) {
		deviceMin = (SInt16)0x8001;
		debug2IOLog ("deviceMin adjusted to = %d\n", deviceMin);
	}

	deviceMinDB = ConvertUSBVolumeTodB (deviceMin);
	deviceMaxDB = ConvertUSBVolumeTodB (deviceMax);
	resolutionDB = ConvertUSBVolumeTodB (volRes);		// The volume is incremented in units of this many dB, represented as 1/256 dB (eg 256 == 1dB of control)

	offset = -deviceMin;
	debug2IOLog ("offset = %d\n", offset);

/*	The device won't ever report itself being outside of its allowable range -- that would be silly.
	if (currentValue < deviceMin) {
		currentValue = deviceMin;
	} else if (currentValue > deviceMax) {
		currentValue = deviceMax;
	} */

	currentValue = (currentValue + offset) / volRes;
	deviceMax = ((deviceMin + offset) + (deviceMax + offset)) / volRes;
//	FailIf (!super::init (currentValue + offset, deviceMin + offset, deviceMax + offset, deviceMinDB, deviceMaxDB, theChannelNumber, channelName, 0, subType, usage), Exit);
	debug4IOLog ("min = %d, max = %d, current = %d\n", (deviceMin + offset) - 1, deviceMax, currentValue);
	FailIf (FALSE == super::init (currentValue, (deviceMin + offset) - 1, deviceMax, deviceMinDB, deviceMaxDB, theChannelNumber, channelName, 0, subType, usage), Exit);

	result = TRUE;

Exit:
	debug8IOLog ("-AppleUSBAudioLevelControl[%p]::init (%d, %d, %d, %d, %p, %p)\n", this, theUnitID, theInterfaceNumber, theControlSelector, theChannelNumber, theUSBDeviceRequest, properties);
	return result;
}

void AppleUSBAudioLevelControl::free () {
    debug2IOLog ("+AppleUSBAudioLevelControl[%p]::free ()\n", this);

    if (setValueThreadCall) {
        thread_call_free (setValueThreadCall);
        setValueThreadCall = NULL;
    }

    super::free ();
    debug2IOLog ("-AppleUSBAudioLevelControl[%p]::free ()\n", this);
}

IOReturn AppleUSBAudioLevelControl::performValueChange (OSObject * newValue) {
	OSNumber *					newValueAsNumber;
	SInt32						newValueAsSInt32;

    debug3IOLog ("+AppleUSBAudioLevelControl[%p]::performValueChange (%d)\n", this, newValue); 

	newValueAsNumber = OSDynamicCast (OSNumber, newValue);
	FailIf (NULL == newValueAsNumber, Exit);
	newValueAsSInt32 = newValueAsNumber->unsigned32BitValue ();
	debug3IOLog ("++AppleUSBAudioLevelControl[%p]::performValueChange (%ld)\n", this, newValueAsSInt32);

    // updateUSBValue ();
    // We should just be able to make an asynchronous deviceRequest, but for some reason that doesn't want to work
    // we get pipe stall errors and the change is never made

    assert (setValueThreadCall);
    thread_call_enter1 (setValueThreadCall, (thread_call_param_t)newValueAsSInt32);

    debug3IOLog ("-AppleUSBAudioLevelControl[%p]::performValueChange (%d)\n", this, newValueAsSInt32);

Exit:
    return kIOReturnSuccess;
}

void AppleUSBAudioLevelControl::updateUSBValue () {
    updateUSBValue (getIntValue ());
}

void AppleUSBAudioLevelControl::updateUSBValue (SInt32 newValue) {
	SInt32						newiSubVolume;
    SInt16						theValue;
	SInt16						newVolume;
    IOReturn					ret;

    debug3IOLog ("+AppleUSBAudioLevelControl[%p]::updateUSBValue (%d)\n", this, newValue);

	if (newValue < 0) {
		newVolume = 0x8000;
	} else {
		newVolume = (newValue * volRes) - offset;
	}
    theValue = HostToUSBWord (newVolume);
	debug2IOLog ("setting volume to 0x%X\n", newVolume);
	ret = SetCurVolume (interfaceNumber, channelNumber, theValue);

	// If this is the iSub volume control, don't bother to look for ourselves, which would probably result in an infinite loop anyway.
	if (getSubType () != 'subL' && getSubType () != 'subR') {
		IOAudioLevelControl *	iSubVolume;
		IORegistryEntry *		start;
		IORegistryEntry *		parent;
		IORegistryEntry *		engine;

		iSubVolume = NULL;
		debugIOLog ("Looking for iSub volume control\n");
		start = getParentEntry (gIOServicePlane);
		FailIf (NULL == start, Exit);
		parent = start->getParentEntry (gIOServicePlane);
		FailIf (NULL == parent, Exit);
		engine = parent->childFromPath ("AppleUSBAudioEngine", gIOServicePlane);
		FailIf (NULL == engine, Exit);

		if (1 == channelNumber) {
			iSubVolume = (IOAudioLevelControl *)FindEntryByNameAndProperty (engine, "AppleUSBAudioLevelControl", kIOAudioControlSubTypeKey, 'subL');
		} else if (2 == channelNumber) {
			iSubVolume = (IOAudioLevelControl *)FindEntryByNameAndProperty (engine, "AppleUSBAudioLevelControl", kIOAudioControlSubTypeKey, 'subR');
		}

		engine->release ();

		FailIf (NULL == iSubVolume, Exit);
		newiSubVolume = (newValue * 60) / getMaxValue ();
		debugIOLog ("Setting the iSub volume control\n");
		iSubVolume->setValue (newiSubVolume);
		iSubVolume->release ();
	}

Exit:
    if (ret != kIOReturnSuccess) {
        debug4IOLog ("++AppleUSBAudioLevelContol:updateUSBValue () - set current value for %d:%d failed: 0x%X\n", controlSelector, channelNumber, ret);
    }

    debug3IOLog ("-AppleUSBAudioLevelControl[%p]::updateUSBValue (%d)\n", this, newValue);
}

SInt16 AppleUSBAudioLevelControl::GetCurVolume (UInt8 interfaceNumber, UInt8 channelNumber, IOReturn * error) {
    IOUSBDevRequest				devReq;
    SInt16						theVolume;

    devReq.bmRequestType = USBmakebmRequestType (kUSBIn, kUSBClass, kUSBInterface);
    devReq.bRequest = GET_CUR;
    devReq.wValue = (controlSelector << 8) | channelNumber;
    devReq.wIndex = (unitID << 8) | interfaceNumber;
    devReq.wLength = 2;
    devReq.pData = &theVolume;

//    *error = audioDevice->deviceRequest (&devReq);
	*error = usbDeviceRequest (&devReq, callerRefCon);
    FailIf (kIOReturnSuccess != *error, Error);

Exit:
    return USBToHostWord (theVolume);
Error:
	theVolume = 0;
	goto Exit;
}

SInt16 AppleUSBAudioLevelControl::GetMaxVolume (UInt8 interfaceNumber, UInt8 channelNumber, IOReturn * error) {
    IOUSBDevRequest				devReq;
    SInt16						theVolume;

    devReq.bmRequestType = USBmakebmRequestType (kUSBIn, kUSBClass, kUSBInterface);
    devReq.bRequest = GET_MAX;
    devReq.wValue = (controlSelector << 8) | channelNumber;
    devReq.wIndex = (unitID << 8) | interfaceNumber;
    devReq.wLength = 2;
    devReq.pData = &theVolume;

	*error = usbDeviceRequest (&devReq, callerRefCon);
    FailIf (kIOReturnSuccess != *error, Error);

Exit:
    return USBToHostWord (theVolume);
Error:
	theVolume = 0;
	goto Exit;
}

SInt16 AppleUSBAudioLevelControl::GetMinVolume (UInt8 interfaceNumber, UInt8 channelNumber, IOReturn * error) {
    IOUSBDevRequest				devReq;
    SInt16						theVolume;

    devReq.bmRequestType = USBmakebmRequestType (kUSBIn, kUSBClass, kUSBInterface);
    devReq.bRequest = GET_MIN;
    devReq.wValue = (controlSelector << 8) | channelNumber;
    devReq.wIndex = (unitID << 8) | interfaceNumber;
    devReq.wLength = 2;
    devReq.pData = &theVolume;

	*error = usbDeviceRequest (&devReq, callerRefCon);
    FailIf (kIOReturnSuccess != *error, Error);

Exit:
    return USBToHostWord (theVolume);
Error:
	theVolume = 0;
	goto Exit;
}

UInt16 AppleUSBAudioLevelControl::GetVolumeResolution (UInt8 interfaceNumber, UInt8 channelNumber, IOReturn * error) {
    IOUSBDevRequest				devReq;
    UInt16						theResolution;

    devReq.bmRequestType = USBmakebmRequestType (kUSBIn, kUSBClass, kUSBInterface);
    devReq.bRequest = GET_RES;
    devReq.wValue = (controlSelector << 8) | channelNumber;
    devReq.wIndex = (unitID << 8) | interfaceNumber;
    devReq.wLength = 2;
    devReq.pData = &theResolution;

	*error = usbDeviceRequest (&devReq, callerRefCon);
    FailIf (kIOReturnSuccess != *error, Error);

Exit:
    return USBToHostWord (theResolution);
Error:
	theResolution = 0;
	goto Exit;
}

IOReturn AppleUSBAudioLevelControl::SetCurVolume (UInt8 interfaceNumber, UInt8 channelNumber, SInt16 volume) {
    IOUSBDevRequest				devReq;
	IOReturn					error;

    devReq.bmRequestType = USBmakebmRequestType (kUSBOut, kUSBClass, kUSBInterface);
    devReq.bRequest = SET_CUR;
    devReq.wValue = (controlSelector << 8) | channelNumber;
    devReq.wIndex = (unitID << 8) | interfaceNumber;
    devReq.wLength = 2;
    devReq.pData = &volume;

	error = usbDeviceRequest (&devReq, callerRefCon);
    FailIf (kIOReturnSuccess != error, Exit);

Exit:
    return error;
}

void AppleUSBAudioLevelControl::updateValueCallback (void *arg1, void *arg2) {
    AppleUSBAudioLevelControl 		*levelControl;
    UInt32							value;

    debug3IOLog ("+AppleUSBAudioLevelControl::updateValueCallback (%p, %p)\n", (UInt32*)arg1, (UInt32*)arg2);
    levelControl = (AppleUSBAudioLevelControl *)arg1;
    value = (UInt32)arg2;

    if (levelControl && OSDynamicCast (AppleUSBAudioLevelControl, levelControl)) {
        levelControl->updateUSBValue (value);
    }

    debug3IOLog ("-AppleUSBAudioLevelControl::updateValueCallback (%p, %p)\n", (UInt32*)arg1, (UInt32*)arg2);
}

// This is how the thing is defined in the USB Audio spec (section 5.2.2.4.3.2 for the curious).
// The volume setting of a device is described in 1/256 dB increments using a number that goes from
// a max of 0x7fff (127.9961 dB) down to 0x8001 (-127.9961 dB) using standard signed math, but 0x8000
// is actually negative infinity (not -128 dB), so I have to special case it.
IOFixed AppleUSBAudioLevelControl::ConvertUSBVolumeTodB (SInt16 volume) {
	IOFixed							dBVolumeFixed;

	if (volume == (SInt16)0x8000) {
		dBVolumeFixed = ((SInt16)0x8000 * 256) << 8;	// really is negative infinity
	} else {
		dBVolumeFixed = volume * 256;
	}

	debug3IOLog ("volume = %d, dBVolumeFixed = 0x%X\n", volume, dBVolumeFixed);

	return dBVolumeFixed;
}

IORegistryEntry * AppleUSBAudioLevelControl::FindEntryByNameAndProperty (const IORegistryEntry * start, const char * name, const char * key, UInt32 value) {
	OSIterator				*iterator;
	IORegistryEntry			*theEntry;
	IORegistryEntry			*tmpReg;
	OSNumber				*tmpNumber;

	theEntry = NULL;
	iterator = NULL;
	FailIf (NULL == start, Exit);

	iterator = start->getChildIterator (gIOServicePlane);
	FailIf (NULL == iterator, Exit);

	while (NULL == theEntry && (tmpReg = OSDynamicCast (IORegistryEntry, iterator->getNextObject ())) != NULL) {
		if (strcmp (tmpReg->getName (), name) == 0) {
			tmpNumber = OSDynamicCast (OSNumber, tmpReg->getProperty (key));
			if (NULL != tmpNumber && tmpNumber->unsigned32BitValue () == value) {
				theEntry = tmpReg;
				theEntry->retain ();
			}
		}
	}

Exit:
	if (NULL != iterator) {
		iterator->release ();
	}
	return theEntry;
}