Code to control a Traxster robot using a Wimote and Android app

Dependencies:   mbed

Fork of BlueUSB by Peter Barrett

Revision:
1:accdaa84fe8d
Parent:
0:606b230e5b4a
diff -r 606b230e5b4a -r accdaa84fe8d BlueUSB/USBHost.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/BlueUSB/USBHost.cpp	Mon Apr 28 16:06:32 2014 +0000
@@ -0,0 +1,1072 @@
+
+/*
+Copyright (c) 2010 Peter Barrett
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include "mbed.h"
+#include "USBHost.h"
+
+//	Config (default uses x bytes)
+#define MAX_DEVICES 8				// Max number of devices
+#define MAX_ENDPOINTS_TOTAL 16		// Max number of endpoints total
+#define MAX_ENDPOINTS_PER_DEVICE 8	// Max number of endpoints for any one device
+
+#define  USBLOG 1
+#if USBLOG
+#define  LOG(...)       printf(__VA_ARGS__)
+#else 
+#define  LOG(...)       do {} while(0)
+#endif
+
+// USB host structures
+
+#define USB_RAM_SIZE 16*1024	// AHB SRAM block 1 TODO MACHINE DEPENDENT
+#define USB_RAM_BASE 0x2007C000
+
+#define TOKEN_SETUP 0
+#define TOKEN_IN  1
+#define TOKEN_OUT 2
+
+//	Status flags from hub
+#define PORT_CONNECTION 0
+#define PORT_ENABLE  1
+#define PORT_SUSPEND  2
+#define PORT_OVER_CURRENT 3
+#define PORT_RESET 4
+#define PORT_POWER 8
+#define PORT_LOW_SPEED 9
+
+#define C_PORT_CONNECTION 16
+#define C_PORT_ENABLE 17
+#define C_PORT_SUSPEND 18
+#define C_PORT_OVER_CURRENT 19
+#define C_PORT_RESET 20
+
+typedef struct {
+	u8 bm_request_type;
+	u8 b_request;
+	u16 w_value;
+	u16 w_index;
+	u16 w_length;
+} Setup;
+
+
+//	Hub stuff is kept private just to keep api simple
+int SetPortFeature(int device, int feature, int index);
+int ClearPortFeature(int device, int feature, int index);
+int SetPortPower(int device, int port);
+int SetPortReset(int device, int port);
+int GetPortStatus(int device, int port, u32* status);
+
+//===================================================================
+//===================================================================
+//	Hardware defines
+
+//	HcControl
+#define PeriodicListEnable	0x00000004
+#define	IsochronousEnable	0x00000008
+#define	ControlListEnable	0x00000010
+#define	BulkListEnable		0x00000020
+#define	OperationalMask		0x00000080
+#define	HostControllerFunctionalState	0x000000C0
+
+//	HcCommandStatus
+#define HostControllerReset	0x00000001
+#define ControlListFilled	0x00000002
+#define BulkListFilled		0x00000004
+
+//	HcInterruptStatus Register
+#define	WritebackDoneHead		0x00000002
+#define	StartofFrame			0x00000004
+#define ResumeDetected			0x00000008
+#define UnrecoverableError		0x00000010
+#define FrameNumberOverflow		0x00000020
+#define RootHubStatusChange		0x00000040
+#define OwnershipChange			0x00000080
+#define MasterInterruptEnable	0x80000000
+
+//	HcRhStatus
+#define SetGlobalPower			0x00010000
+#define DeviceRemoteWakeupEnable	0x00008000
+
+//	HcRhPortStatus (hub 0, port 1)
+#define CurrentConnectStatus	0x00000001
+#define	PortEnableStatus		0x00000002
+#define PortSuspendStatus		0x00000004
+#define PortOverCurrentIndicator	0x00000008
+#define PortResetStatus			0x00000010
+
+#define PortPowerStatus			0x00000100
+#define LowspeedDevice			0x00000200
+#define HighspeedDevice			0x00000400
+
+#define ConnectStatusChange	(CurrentConnectStatus << 16)
+#define PortResetStatusChange	(PortResetStatus << 16)
+
+
+#define  TD_ROUNDING		(u32)0x00040000
+#define  TD_SETUP			(u32)0x00000000
+#define  TD_IN				(u32)0x00100000
+#define  TD_OUT				(u32)0x00080000
+#define  TD_DELAY_INT(x)	(u32)((x) << 21)
+#define  TD_TOGGLE_0		(u32)0x02000000
+#define  TD_TOGGLE_1		(u32)0x03000000
+#define  TD_CC				(u32)0xF0000000
+
+//	HostController EndPoint Descriptor
+typedef struct {
+	volatile u32	Control;
+	volatile u32	TailTd;
+	volatile u32	HeadTd;
+	volatile u32	Next;
+} HCED;
+
+// HostController Transfer Descriptor
+typedef struct {
+	volatile u32	Control;
+	volatile u32	CurrBufPtr;
+	volatile u32	Next;
+	volatile u32	BufEnd;
+} HCTD;
+
+// Host Controller Communication Area
+typedef struct {
+	volatile u32	InterruptTable[32];
+	volatile u16	FrameNumber;
+	volatile u16	FrameNumberPad;
+	volatile u32	DoneHead;
+	volatile u8		Reserved[120];
+} HCCA;
+
+//====================================================================================
+//====================================================================================
+
+class HostController;
+class Endpoint;
+class Device;
+
+//	  must be 3*16 bytes long
+class Endpoint
+{
+public:
+	HCED	EndpointDescriptor;    // Pointer to EndpointDescriptor == Pointer to Endpoint
+	HCTD	TDHead;
+
+	enum State
+	{
+		Free,
+		NotQueued,
+		Idle,
+		SetupQueued,
+		DataQueued,
+		StatusQueued,
+		CallbackPending
+	};
+	
+	volatile u8 CurrentState;
+	u8		Flags;			// 0x80 In, 0x03 mask endpoint type
+
+	u16		Length;
+	u8*		Data;
+	USBCallback Callback;	 // Must be a multiple of 16 bytes long
+	void*  UserData;
+  
+	int Address()
+	{
+		int ep = (EndpointDescriptor.Control >> 7) & 0xF;
+		if (ep)
+			ep |= Flags & 0x80;
+		return ep;
+	}
+	
+	int Device()
+	{
+		return EndpointDescriptor.Control & 0x7F;
+	}
+
+	int Status()
+	{
+		return (TDHead.Control >> 28) & 0xF;
+	}
+
+	u32 Enqueue(u32 head)
+	{
+		if (CurrentState == NotQueued)
+		{
+			EndpointDescriptor.Next = head;
+			head = (u32)&EndpointDescriptor;
+			CurrentState = Idle;
+		}
+		return head;
+	}
+};
+
+class Device
+{
+public:
+	u8	_endpointMap[MAX_ENDPOINTS_PER_DEVICE*2];
+	u8	Hub;
+	u8	Port;
+	u8	Addr;
+	u8	Pad;
+
+	//	Only if this device is a hub
+	u8	HubPortCount;	// nonzero if this is a hub
+	u8	HubInterruptData;
+	u8	HubMap;
+	u8	HubMask;
+
+	int Flags;		// 1 = Disconnected
+
+	Setup	SetupBuffer;
+
+	// Allocate endpoint zero
+	int Init(DeviceDescriptor* d, int hub, int port, int addr, int lowSpeed)
+	{
+		Hub = hub;
+		Port = port;
+		Addr = addr;
+		Flags = lowSpeed;
+		memset(_endpointMap,0xFF,sizeof(_endpointMap));
+		return 0;
+	}
+
+	int SetEndpointIndex(int ep, int endpointIndex)
+	{
+		for (int i = 0; i < MAX_ENDPOINTS_PER_DEVICE*2; i += 2)
+		{
+			if (_endpointMap[i] == 0xFF)	// Add endpoint to map
+			{
+				_endpointMap[i] = ep;
+				_endpointMap[i+1] = endpointIndex;
+				return 0;
+			}
+		}
+		return ERR_ENDPOINT_NONE_LEFT;
+	}
+
+	int GetEndpointIndex(int ep)
+	{
+		for (int i = 0; i < MAX_ENDPOINTS_PER_DEVICE*2; i += 2)
+		{
+			if (_endpointMap[i] == ep)
+				return _endpointMap[i+1];
+			if (_endpointMap[i] == 0xFF)
+				break;
+		}
+		return -1;
+	}
+};
+
+class HostController
+{
+public:
+	HCCA		CommunicationArea;
+	Endpoint	Endpoints[MAX_ENDPOINTS_TOTAL];    // Multiple of 16
+	
+	Endpoint	EndpointZero;						// For device enumeration
+	HCTD		_commonTail;
+	Setup		_setupZero;
+	
+	Device	Devices[MAX_DEVICES];
+	u32	_frameNumber;			// 32 bit ms counter
+
+	u8	_callbacksPending;		//	Endpoints with callbacks are pending, set from ISR via ProcessDoneQueue
+	u8	_rootHubStatusChange;	//	Root hub status has changed, set from ISR
+	u8	_unused0;
+	u8	_unused1;
+
+	u8	_connectPending;	//	Reset has initiated a connect
+	u8	_connectCountdown;	//	Number of ms left after reset before we can connect
+	u8	_connectHub;		//	Will connect on this hub
+	u8	_connectPort;		//	... and this port
+
+	u8	SRAM[0];			// Start of free SRAM
+
+	void Loop()
+	{
+		u16 elapsed = CommunicationArea.FrameNumber - (u16)_frameNumber;	// extend to 32 bits
+		_frameNumber += elapsed;
+
+		// Do callbacks, if any
+		while (_callbacksPending)
+		{
+			for (int i = 0; i < MAX_ENDPOINTS_TOTAL; i++)
+			{
+				Endpoint* endpoint = Endpoints + i;
+				if (endpoint->CurrentState == Endpoint::CallbackPending)
+				{
+					_callbacksPending--;
+					endpoint->CurrentState = Endpoint::Idle;
+					endpoint->Callback(endpoint->Device(),endpoint->Address(),endpoint->Status(),endpoint->Data,endpoint->Length,endpoint->UserData);
+				}
+			}
+		}
+
+		//	Deal with changes on the root hub
+		if (_rootHubStatusChange)
+		{
+			u32 status = LPC_USB->HcRhPortStatus1;
+			_rootHubStatusChange = 0;
+			if (status >> 16)
+			{
+				HubStatusChange(0,1,status);
+				LPC_USB->HcRhPortStatus1 = status & 0xFFFF0000;	// clear status changes
+			}
+		}
+
+		//	Connect after reset timeout
+		if (_connectCountdown)
+		{
+			if (elapsed >= _connectCountdown)
+			{
+				_connectCountdown = 0;
+				Connect(_connectHub,_connectPort & 0x7F,_connectPort & 0x80);
+			} else
+				_connectCountdown -= elapsed;
+		}
+	}
+
+	//	HubInterrupt - bitmap in dev->HubInterruptData
+	void HubInterrupt(int device)
+	{
+		Device* dev = &Devices[device-1];
+		for (int i = 0; i < dev->HubPortCount; i++)
+		{
+			int port = i+1;
+			if (dev->HubInterruptData & (1 << port))
+			{
+				u32 status = 0;
+				GetPortStatus(device,port,&status);
+				if (status >> 16)
+				{
+					if (_connectPending && (status & ConnectStatusChange))
+						continue;	// Don't connect again until previous device has been added and addressed
+
+					HubStatusChange(device,port,status);
+					if (status & ConnectStatusChange)
+						ClearPortFeature(device,C_PORT_CONNECTION,port);
+					if (status & PortResetStatusChange)
+						ClearPortFeature(device,C_PORT_RESET,port);
+				}
+			}
+		}
+	}
+
+	static void HubInterruptCallback(int device, int endpoint, int status, u8* data, int len, void* userData)
+	{
+		HostController* controller = (HostController*)userData;
+		if (status == 0)
+			controller->HubInterrupt(device);
+		USBInterruptTransfer(device,endpoint,data,1,HubInterruptCallback,userData);
+	}
+
+	int InitHub(int device)
+	{
+		u8 buf[16];
+		int r= USBControlTransfer(device,DEVICE_TO_HOST | REQUEST_TYPE_CLASS | RECIPIENT_DEVICE,GET_DESCRIPTOR,(DESCRIPTOR_TYPE_HUB << 8),0,buf,sizeof(buf));
+		if (r < 0)
+			return ERR_HUB_INIT_FAILED;
+	    
+		//	turn on power on the hubs ports
+		Device* dev = &Devices[device-1];
+		int ports = buf[2];
+		dev->HubPortCount = ports;
+		for (int i = 0; i < ports; i++)
+			SetPortPower(device,i+1);
+	    
+		// Enable hub change interrupts
+		return USBInterruptTransfer(device,0x81,&dev->HubInterruptData,1,HubInterruptCallback,this);
+	}
+	
+	int AddEndpoint(int device, int ep, int attributes, int maxPacketSize, int interval)
+	{
+		LOG("AddEndpoint D:%02X A:%02X T:%02X P:%04X I:%02X\n",device,ep,attributes,maxPacketSize,interval);
+		Device* dev = &Devices[device-1];
+		Endpoint* endpoint = AllocateEndpoint(device,ep,attributes,maxPacketSize);
+		if (!endpoint)
+			return ERR_ENDPOINT_NONE_LEFT;
+		dev->SetEndpointIndex(ep,endpoint - Endpoints);
+		endpoint->EndpointDescriptor.Control |= dev->Flags; // Map in slow speed
+		return 0;  // TODO ed->bInterval
+	}
+	
+	int AddEndpoint(int device, EndpointDescriptor* ed)
+	{
+		return AddEndpoint(device,ed->bEndpointAddress,ed->bmAttributes,ed->wMaxPacketSize,ed->bInterval);
+	}
+
+	//	  allocate a endpoint
+	Endpoint* AllocateEndpoint(int device, int endpointAddress, int type, int maxPacketSize)
+	{
+		for (int i = 0; i < MAX_ENDPOINTS_TOTAL; i++)
+		{
+			Endpoint* ep = &Endpoints[i];
+			if (ep->CurrentState == 0)
+			{
+				//LOG("Allocated endpoint %d to %02X:%02X\n",i,device,endpointAddress);
+				ep->Flags = (endpointAddress & 0x80) | (type & 3);
+				ep->CurrentState = Endpoint::NotQueued;
+				ep->EndpointDescriptor.Control = (maxPacketSize << 16) | ((endpointAddress & 0x7F) << 7) | device;
+				return ep;
+			}
+		}
+		return 0;
+	}
+
+	Endpoint* GetEndpoint(int device, int ep)
+	{
+		if (device == 0)
+		{
+			//printf("WARNING: USING DEVICE 0\n");
+			return &EndpointZero;
+		}
+		if (device > MAX_DEVICES)
+			return 0;
+		int i = Devices[device-1].GetEndpointIndex(ep);
+		if (i == -1)
+			return 0;
+		return Endpoints + i;
+	}
+
+	int Transfer(Endpoint* endpoint, int token, u8* data, int len, int state)
+	{
+		//LOG("Transfer %02X T:%d Len:%d S:%d\n",endpoint->Address(),token,len,state);
+	
+		int toggle = 0;
+		if (endpoint->Address() == 0)
+			toggle = (token == TOKEN_SETUP) ? TD_TOGGLE_0 : TD_TOGGLE_1;
+
+		if (token != TOKEN_SETUP)
+			token = (token == TOKEN_IN ? TD_IN : TD_OUT);
+
+		HCTD* head = &endpoint->TDHead;
+		HCTD* tail = &_commonTail;
+
+		head->Control = TD_ROUNDING | token | TD_DELAY_INT(0) | toggle | TD_CC; 
+		head->CurrBufPtr = (u32)data;
+		head->BufEnd = (u32)(data + len - 1);
+		head->Next = (u32)tail;
+
+		HCED* ed = &endpoint->EndpointDescriptor;
+		ed->HeadTd = (u32)head | (ed->HeadTd & 0x00000002);    // carry toggle
+		ed->TailTd = (u32)tail;
+		
+		//HCTD* td = head;
+		//LOG("%04X TD %08X %08X %08X Next:%08X\n",CommunicationArea.FrameNumber,td->Control,td->CurrBufPtr,td->BufEnd,td->Next);
+		//LOG("%04X ED %08X %08X %08X\n",CommunicationArea.FrameNumber,ed->Control,ed->HeadTd,ed->TailTd);
+		
+		switch (endpoint->Flags & 3)
+		{
+			case ENDPOINT_CONTROL:
+				LPC_USB->HcControlHeadED = endpoint->Enqueue(LPC_USB->HcControlHeadED);    // May change state NotQueued->Idle
+				endpoint->CurrentState = state;											   // Get in before an int
+				LPC_USB->HcCommandStatus = LPC_USB->HcCommandStatus | ControlListFilled;
+				LPC_USB->HcControl = LPC_USB->HcControl | ControlListEnable;
+				break;
+
+			case ENDPOINT_BULK:
+				LPC_USB->HcBulkHeadED = endpoint->Enqueue(LPC_USB->HcBulkHeadED);
+				endpoint->CurrentState = state;
+				LPC_USB->HcCommandStatus = LPC_USB->HcCommandStatus | BulkListFilled;
+				LPC_USB->HcControl = LPC_USB->HcControl | BulkListEnable;
+				break;
+
+			case ENDPOINT_INTERRUPT:
+				CommunicationArea.InterruptTable[0] = endpoint->Enqueue(CommunicationArea.InterruptTable[0]);
+				endpoint->CurrentState = state;
+				LPC_USB->HcControl |= PeriodicListEnable;
+				break;
+		}
+		return 0;
+	}
+	
+	//	Remove an endpoint from an active queue
+	bool Remove(HCED* ed, volatile HCED** queue)
+	{
+		if (*queue == 0)
+			return false;
+		if (*queue == (volatile HCED*)ed)
+		{
+			*queue = (volatile HCED*)ed->Next;	// At head of queue
+			return true;
+		}
+
+		volatile HCED* head = *queue;
+		while (head)
+		{
+			if (head->Next == (u32)ed)
+			{
+				head->Next = ed->Next;
+				return true;
+			}
+			head = (volatile HCED*)head->Next;
+		}
+		return false;
+	}
+
+	void Release(Endpoint* endpoint)
+	{
+		if (endpoint->CurrentState == Endpoint::NotQueued)
+		{
+			// Never event used it, nothing to do
+		}
+		else
+		{
+			HCED* ed = (HCED*)endpoint;
+			ed->Control |= 0x4000;	// SKIP
+			switch (endpoint->Flags & 0x03)
+			{
+				case ENDPOINT_CONTROL:
+					Remove(ed,(volatile HCED**)&LPC_USB->HcControlHeadED);
+					break;
+				case ENDPOINT_BULK:
+					Remove(ed,(volatile HCED**)&LPC_USB->HcBulkHeadED);
+					break;
+				case ENDPOINT_INTERRUPT:
+					for (int i = 0; i < 32; i++)
+						Remove(ed,(volatile HCED**)&CommunicationArea.InterruptTable[i]);
+					break;
+			}
+
+			u16 fn = CommunicationArea.FrameNumber;
+			while (fn == CommunicationArea.FrameNumber)
+				;	// Wait for next frame
+
+		}
+
+		//	In theory, the endpoint is now dead.
+		//	TODO: Will Callbacks ever be pending? BUGBUG
+		memset(endpoint,0,sizeof(Endpoint));
+	}
+
+	//	  Pop the last TD from the list
+	HCTD* Reverse(HCTD* current) 
+	{ 
+		HCTD *result = NULL,*temp; 
+		while (current) 
+		{ 
+			temp = (HCTD*)current->Next; 
+			current->Next = (u32)result;
+			result = current;
+			current = temp;
+		}
+		return result;
+	}
+
+	//	  Called from interrupt...
+	//	  Control endpoints use a state machine to progress through the transfers
+	void ProcessDoneQueue(u32 tdList)
+	{
+		HCTD* list = Reverse((HCTD*)tdList);
+		while (list)
+		{
+			Endpoint* endpoint = (Endpoint*)(list-1);
+			list = (HCTD*)list->Next;
+			int ep = endpoint->Address();
+			bool in = endpoint->Flags & 0x80;
+			int status = (endpoint->TDHead.Control >> 28) & 0xF;
+
+			//LOG("ProcessDoneQueue %02X %08X\n",ep,endpoint->TDHead.Control);
+
+			if (status != 0)
+			{
+				LOG("ProcessDoneQueue status %02X %d\n",ep,status);
+				endpoint->CurrentState = Endpoint::Idle;
+			} else {
+				switch (endpoint->CurrentState)
+				{
+					case Endpoint::SetupQueued:
+						if (endpoint->Length == 0)
+							Transfer(endpoint,in ? TOKEN_OUT : TOKEN_IN,0,0,Endpoint::StatusQueued);	// Skip Data Phase
+						else
+							Transfer(endpoint,in ? TOKEN_IN : TOKEN_OUT,endpoint->Data,endpoint->Length, Endpoint::DataQueued);    // Setup is done, now Data
+						break;
+
+					case Endpoint::DataQueued:
+						if (endpoint->TDHead.CurrBufPtr)
+							endpoint->Length = endpoint->TDHead.CurrBufPtr - (u32)endpoint->Data;
+
+						if (ep == 0)
+							Transfer(endpoint,in ? TOKEN_OUT : TOKEN_IN,0,0,Endpoint::StatusQueued);	// Data is done, now Status, Control only
+						else
+							endpoint->CurrentState = Endpoint::Idle;
+						break;
+
+					case Endpoint::StatusQueued:	// Transaction is done
+						endpoint->CurrentState = Endpoint::Idle;
+						break;
+				}
+			}
+
+			//	  Complete, flag if we need a callback
+			if (endpoint->Callback && endpoint->CurrentState == Endpoint::Idle)
+			{
+				endpoint->CurrentState = Endpoint::CallbackPending;
+				_callbacksPending++;
+			}
+		}
+	}
+
+	//	Hack to reset devices that don't want to connect
+	int AddDevice(int hub, int port, bool isLowSpeed)
+	{
+		int device = AddDeviceCore(hub,port,isLowSpeed);
+        if (device < 0)
+		{
+			LOG("========RETRY ADD DEVICE========\n");	// This will go for ever.. TODO power cycle root?
+            Disconnect(hub,port);	// Could not read descriptor at assigned address, reset this port and try again
+            ResetPort(hub,port);	// Cheap bluetooth dongles often need this on a hotplug
+            return -1;
+        }
+		return device;
+	}
+
+	int AddDeviceCore(int hub, int port, bool isLowSpeed)
+	{
+		int lowSpeed = isLowSpeed ? 0x2000 : 0;
+		DeviceDescriptor desc;
+		EndpointZero.EndpointDescriptor.Control = (8 << 16) | lowSpeed;			   // MaxPacketSize == 8
+		int r = GetDescriptor(0,DESCRIPTOR_TYPE_DEVICE,0,(u8*)&desc,8);
+		if (r < 0)
+		{
+			LOG("FAILED TO LOAD DESCRIPTOR FOR DEVICE 0\n");
+			return r;
+		}
+
+		EndpointZero.EndpointDescriptor.Control = (desc.bMaxPacketSize << 16) | lowSpeed;	 // Actual MaxPacketSize
+		r = GetDescriptor(0,DESCRIPTOR_TYPE_DEVICE,0,(u8*)&desc,sizeof(desc));
+		if (r < 0)
+			return r;
+
+		LOG("\nClass %02X found %04X:%04X\n\n",desc.bDeviceClass,desc.idVendor,desc.idProduct);
+
+		//	  Now assign the device an address, move off EndpointZero
+		int device = 0;
+		for (int i = 0; i < MAX_DEVICES; i++)
+		{
+			if (Devices[i].Port == 0)
+			{
+				device = i+1;
+				break;
+			}
+		}
+		if (!device)
+			return ERR_DEVICE_NONE_LEFT;
+
+		r = SetAddress(0,device);
+		if (r)
+			return r;
+		DelayMS(2);
+		
+		// Now at a nonzero address, create control endpoint
+		Device* dev = &Devices[device-1];
+		dev->Init(&desc,hub,port,device,lowSpeed);
+		AddEndpoint(device,0,ENDPOINT_CONTROL,desc.bMaxPacketSize,0);
+		_connectPending = 0;
+
+		//	Verify this all works
+		r = GetDescriptor(device,DESCRIPTOR_TYPE_DEVICE,0,(u8*)&desc,sizeof(desc));
+		if (r < 0)
+			return r;
+
+		//	Set to interface 0 by default
+		//	Calls LoadDevice if interface is found
+		r = SetConfigurationAndInterface(device,1,0,&desc);
+
+		if (desc.bDeviceClass == CLASS_HUB)
+			InitHub(device);			// Handle hubs in this code
+
+		return device;
+	}
+
+	// Walk descriptors and create endpoints for a given device
+	// TODO configuration !=1, alternate settings etc.
+	int SetConfigurationAndInterface(int device, int configuration, int interfaceNumber, DeviceDescriptor* desc)
+	{
+		u8 buffer[255];
+		int err = GetDescriptor(device,DESCRIPTOR_TYPE_CONFIGURATION,0,buffer,sizeof(buffer));
+		if (err < 0)
+			return err;
+
+		err = SetConfiguration(device,configuration);
+		if (err < 0)
+			return err;
+
+		//	Add the endpoints for this interface
+		int len = buffer[2] | (buffer[3] << 8);
+		u8* d = buffer;
+		u8* end = d + len;
+		InterfaceDescriptor* found = 0;
+		while (d < end)
+		{
+			if (d[1] == DESCRIPTOR_TYPE_INTERFACE)
+			{
+				InterfaceDescriptor* id = (InterfaceDescriptor*)d;
+				if (id->bInterfaceNumber == interfaceNumber)
+				{
+					found = id;
+					d += d[0];
+					while (d < end && d[1] != DESCRIPTOR_TYPE_INTERFACE)
+					{
+						switch (d[1])
+						{
+							case DESCRIPTOR_TYPE_ENDPOINT:
+								AddEndpoint(device,(EndpointDescriptor*)d);
+								break;
+							default:
+								LOG("Skipping descriptor %02X (%d bytes)\n",d[1],d[0]);
+						}
+						d += d[0];
+					}
+				}
+			}
+			d += d[0];
+		}
+
+		if (!found)
+			return ERR_INTERFACE_NOT_FOUND;
+		OnLoadDevice(device,desc,found);
+		return 0;
+	}
+
+	void Init()
+	{
+		LOG("USB INIT (Controller is %d bytes)\n",sizeof(*this));
+		memset(this,0,sizeof(HostController));
+		EndpointZero.CurrentState = Endpoint::NotQueued;
+		HWInit(&CommunicationArea);
+		DelayMS(10);
+	}
+
+	void ResetPort(int hub, int port)
+	{
+		LOG("ResetPort Hub:%d Port:%d\n",hub,port);
+		_connectPending++;			// Only reset/add 1 device at a time
+		if (hub == 0)
+			LPC_USB->HcRhPortStatus1 = PortResetStatus;	// Reset Root Hub, port 1
+		else
+			SetPortReset(hub,port);	// or reset other hub
+	}
+
+	void Disconnect(int hub, int port)
+	{
+		LOG("Disconnect Hub:%d Port:%d\n",hub,port);	// Mark a device for destruction
+		for (int i = 0; i < MAX_DEVICES; i++)
+		{
+			Device* dev = Devices + i;
+			if (dev->Port == port && dev->Hub == hub)
+			{
+				//	Disconnect everything that is attached to this device if it is a hub
+				for (int p = 0; p < dev->HubPortCount; p++)
+					Disconnect(i+1,p+1);
+
+				//	Now release endpoints
+				for (int j = 1; j < MAX_ENDPOINTS_PER_DEVICE*2; j += 2)
+				{
+					u8 endpointIndex = dev->_endpointMap[j];
+					if (endpointIndex != 0xFF)
+						Release(Endpoints + endpointIndex);
+				}
+				dev->Port = 0;	// Device is now free
+				dev->Flags = 0;
+				return;
+			}
+		}
+	}
+
+	// called after reset
+	void Connect(int hub, int port, bool lowspeed)
+	{
+		LOG("Connect Hub:%d Port:%d %s\n",hub,port,lowspeed ? "slow" : "full");
+		AddDevice(hub,port,lowspeed);
+	}
+
+	// Called from interrupt
+	void HubStatusChange(int hub, int port, u32 status)
+	{
+		LOG("HubStatusChange Hub:%d Port:%d %08X\n",hub,port,status);
+		if (status & ConnectStatusChange)
+		{
+			if (status & CurrentConnectStatus)	// Connecting
+				ResetPort(hub,port);			// Reset to initiate connect (state machine?)
+			else
+				Disconnect(hub,port);
+		}
+
+		if (status & PortResetStatusChange)
+		{
+			if (!(status & PortResetStatus))
+			{
+				_connectCountdown = 200;		// Schedule a connection in 200ms
+				if (status & LowspeedDevice)
+					port |= 0x80;
+				_connectHub = hub;
+				_connectPort = port;
+			}
+		}
+	}
+
+	#define HOST_CLK_EN		(1<<0)
+	#define PORTSEL_CLK_EN	(1<<3)
+	#define AHB_CLK_EN		(1<<4)
+	#define CLOCK_MASK		(HOST_CLK_EN | PORTSEL_CLK_EN | AHB_CLK_EN)
+
+	#define  FRAMEINTERVAL		(12000-1)	// 1ms
+	#define  DEFAULT_FMINTERVAL	((((6 * (FRAMEINTERVAL - 210)) / 7) << 16) | FRAMEINTERVAL)
+
+	void DelayMS(int ms)
+	{
+		u16 f = ms + CommunicationArea.FrameNumber;
+		while (f != CommunicationArea.FrameNumber)
+			;
+	}
+
+	static void HWInit(HCCA* cca)
+	{
+		NVIC_DisableIRQ(USB_IRQn);
+		
+		// turn on power for USB
+		LPC_SC->PCONP		|= (1UL<<31);
+		// Enable USB host clock, port selection and AHB clock
+		LPC_USB->USBClkCtrl |= CLOCK_MASK;
+		// Wait for clocks to become available
+		while ((LPC_USB->USBClkSt & CLOCK_MASK) != CLOCK_MASK)
+			;
+		
+		//	We are a Host
+		LPC_USB->OTGStCtrl |= 1;
+		LPC_USB->USBClkCtrl &= ~PORTSEL_CLK_EN;				// we don't need port selection clock until we do OTG
+		
+		// configure USB pins
+		LPC_PINCON->PINSEL1 &= ~((3<<26)|(3<<28));	
+		LPC_PINCON->PINSEL1 |=	((1<<26)|(1<<28));			// USB D+/D-
+			
+		LPC_PINCON->PINSEL3 &= ~((3 << 6) | (3 << 22));		// USB_PPWR, USB_OVRCR
+		LPC_PINCON->PINSEL3 |= ((2 << 6) | (2 << 22));
+		
+		LPC_PINCON->PINSEL4 &= ~(3 << 18);					// USB_CONNECT
+		LPC_PINCON->PINSEL4 |= (1 << 18);
+
+		//	Reset OHCI block
+		LPC_USB->HcControl		 = 0;
+		LPC_USB->HcControlHeadED = 0;
+		LPC_USB->HcBulkHeadED	 = 0;
+		
+		LPC_USB->HcCommandStatus = HostControllerReset;
+		LPC_USB->HcFmInterval	 = DEFAULT_FMINTERVAL;
+		LPC_USB->HcPeriodicStart = FRAMEINTERVAL*90/100;
+
+		LPC_USB->HcControl	= (LPC_USB->HcControl & (~HostControllerFunctionalState)) | OperationalMask;
+		LPC_USB->HcRhStatus = SetGlobalPower;
+		
+		LPC_USB->HcHCCA = (u32)cca;
+		LPC_USB->HcInterruptStatus |= LPC_USB->HcInterruptStatus;
+		LPC_USB->HcInterruptEnable = MasterInterruptEnable | WritebackDoneHead | RootHubStatusChange | FrameNumberOverflow;
+
+		NVIC_SetPriority(USB_IRQn, 0);
+		NVIC_EnableIRQ(USB_IRQn);
+		while (cca->FrameNumber < 10)
+			;	// 10ms delay before diving in
+	}
+};
+
+//====================================================================================
+//====================================================================================
+//	  Host controller instance and Interrupt handler
+
+static HostController _controller __attribute__((at(USB_RAM_BASE)));
+
+extern "C" void USB_IRQHandler(void) __irq;
+void USB_IRQHandler (void) __irq
+{
+	u32 int_status = LPC_USB->HcInterruptStatus;
+
+	if (int_status & RootHubStatusChange)	//	Root hub status change
+		_controller._rootHubStatusChange++;	//	Just flag the controller, will be processed in USBLoop
+
+	u32 head = 0;
+	if (int_status & WritebackDoneHead)
+	{
+		head = _controller.CommunicationArea.DoneHead;		// Writeback Done
+		_controller.CommunicationArea.DoneHead = 0;
+	}			 
+	LPC_USB->HcInterruptStatus = int_status;
+
+	if (head)
+	   _controller.ProcessDoneQueue(head);	 // TODO - low bit can be set BUGBUG
+}
+
+//====================================================================================
+//====================================================================================
+//	  API Methods
+
+void USBInit()
+{
+	return _controller.Init();
+}
+
+void USBLoop()
+{
+	return _controller.Loop();
+}
+
+u8* USBGetBuffer(u32* len)
+{
+	*len = USB_RAM_SIZE - sizeof(HostController);
+	return _controller.SRAM;
+}
+
+static Setup* GetSetup(int device)
+{
+	if (device == 0)
+		return &_controller._setupZero;
+	
+	if (device < 1 || device > MAX_DEVICES)
+		return 0;
+	return &_controller.Devices[device-1].SetupBuffer;
+}
+
+//	Loop until IO on endpoint is complete
+static int WaitIODone(Endpoint* endpoint)
+{
+	if (endpoint->CurrentState == Endpoint::NotQueued)
+		return 0;
+	while (endpoint->CurrentState != Endpoint::Idle)
+		USBLoop();	// May generate callbacks, mount or unmount devices etc
+	int status = endpoint->Status();
+	if (status == 0)
+		return endpoint->Length;
+	return -status;
+}
+
+int USBTransfer(int device, int ep, u8 flags, u8* data, int length, USBCallback callback, void* userData)
+{
+	Endpoint* endpoint = _controller.GetEndpoint(device,ep);
+	if (!endpoint)
+		return ERR_ENDPOINT_NOT_FOUND;
+		
+	WaitIODone(endpoint);
+	endpoint->Flags = flags;
+	endpoint->Data = data;
+	endpoint->Length = length;
+	endpoint->Callback = callback;
+	endpoint->UserData = userData;
+	if (ep == 0)
+		_controller.Transfer(endpoint,TOKEN_SETUP,(u8*)GetSetup(device),8,Endpoint::SetupQueued);
+	else
+		_controller.Transfer(endpoint,flags & 0x80 ? TOKEN_IN : TOKEN_OUT,data,length,Endpoint::DataQueued);
+	if (callback)
+		return IO_PENDING;
+	return WaitIODone(endpoint);
+}
+
+int USBControlTransfer(int device, int request_type, int request, int value, int index, u8* data, int length, USBCallback callback, void * userData)
+{
+	Setup* setup = GetSetup(device);
+	if (!setup)
+		return ERR_DEVICE_NOT_FOUND;
+		
+	// Async control calls may overwrite setup buffer of previous call, so we need to wait before setting up next call
+	WaitIODone(_controller.GetEndpoint(device,0));
+	
+	setup->bm_request_type = request_type;
+	setup->b_request = request;
+	setup->w_value = value;
+	setup->w_index = index;
+	setup->w_length = length;
+	return USBTransfer(device,0,request_type & DEVICE_TO_HOST,data,length,callback,userData);
+}
+
+int  USBInterruptTransfer(int device, int ep, u8* data, int length, USBCallback callback, void* userData)
+{
+	return USBTransfer(device,ep,(ep & 0x80) | ENDPOINT_INTERRUPT,data,length,callback,userData);
+}
+
+int  USBBulkTransfer(int device, int ep, u8* data, int length, USBCallback callback, void* userData)
+{
+	return USBTransfer(device,ep,(ep & 0x80) | ENDPOINT_BULK,data,length,callback,userData);
+}
+
+int GetDescriptor(int device, int descType,int descIndex, u8* data, int length)
+{
+	return USBControlTransfer(device,DEVICE_TO_HOST | RECIPIENT_DEVICE, GET_DESCRIPTOR,(descType << 8)|(descIndex), 0, data, length, 0);
+}
+
+int GetString(int device, int index, char* dst, int length)
+{
+    u8 buffer[255];
+    int le = GetDescriptor(device,DESCRIPTOR_TYPE_STRING,index,buffer,sizeof(buffer));
+    if (le < 0)
+		return le;
+	if (length < 1)
+		return -1;
+	length <<= 1;
+	if (le > length)
+		le = length;
+    for (int j = 2; j < le; j += 2)
+        *dst++ = buffer[j];
+    *dst = 0;
+	return (le>>1)-1;
+}
+
+int SetAddress(int device, int new_addr)
+{
+	return USBControlTransfer(device,HOST_TO_DEVICE | RECIPIENT_DEVICE, SET_ADDRESS, new_addr, 0, 0, 0, 0);
+}
+
+int SetConfiguration(int device, int configNum)
+{
+	return USBControlTransfer(device,HOST_TO_DEVICE | RECIPIENT_DEVICE, SET_CONFIGURATION, configNum, 0, 0, 0, 0);
+}
+
+int SetInterface(int device, int ifNum, int altNum)
+{
+	return USBControlTransfer(device,HOST_TO_DEVICE | RECIPIENT_INTERFACE, SET_INTERFACE, altNum, ifNum, 0, 0, 0);
+}
+
+//	HUB stuff
+int SetPortFeature(int device, int feature, int index)
+{
+    return USBControlTransfer(device,HOST_TO_DEVICE | REQUEST_TYPE_CLASS | RECIPIENT_OTHER,SET_FEATURE,feature,index,0,0);
+}
+
+int ClearPortFeature(int device, int feature, int index)
+{
+    return USBControlTransfer(device,HOST_TO_DEVICE | REQUEST_TYPE_CLASS | RECIPIENT_OTHER,CLEAR_FEATURE,feature,index,0,0);
+}
+
+int SetPortPower(int device, int port)
+{
+    int r = SetPortFeature(device,PORT_POWER,port);
+    _controller.DelayMS(20);	// 80ms to turn on a hubs power... DESCRIPTOR? todo
+    return r;
+}
+
+int SetPortReset(int device, int port)
+{
+    return SetPortFeature(device,PORT_RESET,port);
+}
+
+int GetPortStatus(int device, int port, u32* status)
+{
+    return USBControlTransfer(device,DEVICE_TO_HOST | REQUEST_TYPE_CLASS | RECIPIENT_OTHER,GET_STATUS,0,port,(u8*)status,4);
+}
\ No newline at end of file