USBCore.cpp

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/* Copyright (c) 2010, Peter Barrett
** Sleep/Wakeup support added by Michael Dreher
**  
** Permission to use, copy, modify, and/or distribute this software for  
** any purpose with or without fee is hereby granted, provided that the  
** above copyright notice and this permission notice appear in all copies.  
** 
** THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL  
** WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED  
** WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR  
** BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES  
** OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,  
** WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,  
** ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS  
** SOFTWARE.  
*/

#include "USBAPI.h"
#include "PluggableUSB.h"
#include <stdlib.h>

#if defined(USBCON)

#define TX_RX_LED_PULSE_MS 100
volatile u8 TxLEDPulse; 
volatile u8 RxLEDPulse; 
//==================================================================
//==================================================================

extern const u16 STRING_LANGUAGE[] PROGMEM;
extern const u8 STRING_PRODUCT[] PROGMEM;
extern const u8 STRING_MANUFACTURER[] PROGMEM;
extern const DeviceDescriptor USB_DeviceDescriptorIAD PROGMEM;
extern bool _updatedLUFAbootloader;

const u16 STRING_LANGUAGE[2] = {
        (3<<8) | (2+2),
        0x0409  // English
};

#ifndef USB_PRODUCT
// If no product is provided, use USB IO Board
#define USB_PRODUCT     "USB IO Board"
#endif

const u8 STRING_PRODUCT[] PROGMEM = USB_PRODUCT;

#if USB_VID == 0x2341
#  if defined(USB_MANUFACTURER)
#    undef USB_MANUFACTURER
#  endif
#  define USB_MANUFACTURER "Arduino LLC"
#elif USB_VID == 0x1b4f
#  if defined(USB_MANUFACTURER)
#    undef USB_MANUFACTURER
#  endif
#  define USB_MANUFACTURER "SparkFun"
#elif !defined(USB_MANUFACTURER)
// Fall through to unknown if no manufacturer name was provided in a macro
#  define USB_MANUFACTURER "Unknown"
#endif

const u8 STRING_MANUFACTURER[] PROGMEM = USB_MANUFACTURER;


#define DEVICE_CLASS 0x02

//      DEVICE DESCRIPTOR
const DeviceDescriptor USB_DeviceDescriptorIAD =
        D_DEVICE(0xEF,0x02,0x01,64,USB_VID,USB_PID,0x100,IMANUFACTURER,IPRODUCT,ISERIAL,1);

//==================================================================
//==================================================================

volatile u8 _usbConfiguration = 0;
volatile u8 _usbCurrentStatus = 0; // meaning of bits see usb_20.pdf, Figure 9-4. Information Returned by a GetStatus() Request to a Device
volatile u8 _usbSuspendState = 0; // copy of UDINT to check SUSPI and WAKEUPI bits

static inline void WaitIN(void)
{
        while (!(UEINTX & (1<<TXINI)))
                ;
}

static inline void ClearIN(void)
{
        UEINTX = ~(1<<TXINI);
}

static inline void WaitOUT(void)
{
        while (!(UEINTX & (1<<RXOUTI)))
                ;
}

static inline u8 WaitForINOrOUT()
{
        while (!(UEINTX & ((1<<TXINI)|(1<<RXOUTI))))
                ;
        return (UEINTX & (1<<RXOUTI)) == 0;
}

static inline void ClearOUT(void)
{
        UEINTX = ~(1<<RXOUTI);
}

static inline void Recv(volatile u8* data, u8 count)
{
        while (count--)
                *data++ = UEDATX;
        
        RXLED1;                                 // light the RX LED
        RxLEDPulse = TX_RX_LED_PULSE_MS;        
}

static inline u8 Recv8()
{
        RXLED1;                                 // light the RX LED
        RxLEDPulse = TX_RX_LED_PULSE_MS;

        return UEDATX;  
}

static inline void Send8(u8 d)
{
        UEDATX = d;
}

static inline void SetEP(u8 ep)
{
        UENUM = ep;
}

static inline u8 FifoByteCount()
{
        return UEBCLX;
}

static inline u8 ReceivedSetupInt()
{
        return UEINTX & (1<<RXSTPI);
}

static inline void ClearSetupInt()
{
        UEINTX = ~((1<<RXSTPI) | (1<<RXOUTI) | (1<<TXINI));
}

static inline void Stall()
{
        UECONX = (1<<STALLRQ) | (1<<EPEN);
}

static inline u8 ReadWriteAllowed()
{
        return UEINTX & (1<<RWAL);
}

static inline u8 Stalled()
{
        return UEINTX & (1<<STALLEDI);
}

static inline u8 FifoFree()
{
        return UEINTX & (1<<FIFOCON);
}

static inline void ReleaseRX()
{
        UEINTX = 0x6B;  // FIFOCON=0 NAKINI=1 RWAL=1 NAKOUTI=0 RXSTPI=1 RXOUTI=0 STALLEDI=1 TXINI=1
}

static inline void ReleaseTX()
{
        UEINTX = 0x3A;  // FIFOCON=0 NAKINI=0 RWAL=1 NAKOUTI=1 RXSTPI=1 RXOUTI=0 STALLEDI=1 TXINI=0
}

static inline u8 FrameNumber()
{
        return UDFNUML;
}

//==================================================================
//==================================================================

u8 USBGetConfiguration(void)
{
        return _usbConfiguration;
}

#define USB_RECV_TIMEOUT
class LockEP
{
        u8 _sreg;
public:
        LockEP(u8 ep) : _sreg(SREG)
        {
                cli();
                SetEP(ep & 7);
        }
        ~LockEP()
        {
                SREG = _sreg;
        }
};

//      Number of bytes, assumes a rx endpoint
u8 USB_Available(u8 ep)
{
        LockEP lock(ep);
        return FifoByteCount();
}

//      Non Blocking receive
//      Return number of bytes read
int USB_Recv(u8 ep, void* d, int len)
{
        if (!_usbConfiguration || len < 0)
                return -1;
        
        LockEP lock(ep);
        u8 n = FifoByteCount();
        len = min(n,len);
        n = len;
        u8* dst = (u8*)d;
        while (n--)
                *dst++ = Recv8();
        if (len && !FifoByteCount())    // release empty buffer
                ReleaseRX();
        
        return len;
}

//      Recv 1 byte if ready
int USB_Recv(u8 ep)
{
        u8 c;
        if (USB_Recv(ep,&c,1) != 1)
                return -1;
        return c;
}

//      Space in send EP
u8 USB_SendSpace(u8 ep)
{
        LockEP lock(ep);
        if (!ReadWriteAllowed())
                return 0;
        return USB_EP_SIZE - FifoByteCount();
}

//      Blocking Send of data to an endpoint
int USB_Send(u8 ep, const void* d, int len)
{
        if (!_usbConfiguration)
                return -1;

        if (_usbSuspendState & (1<<SUSPI)) {
                //send a remote wakeup
                UDCON |= (1 << RMWKUP);
        }

        int r = len;
        const u8* data = (const u8*)d;
        u8 timeout = 250;               // 250ms timeout on send? TODO
        bool sendZlp = false;

        while (len || sendZlp)
        {
                u8 n = USB_SendSpace(ep);
                if (n == 0)
                {
                        if (!(--timeout))
                                return -1;
                        delay(1);
                        continue;
                }

                if (n > len) {
                        n = len;
                }

                {
                        LockEP lock(ep);
                        // Frame may have been released by the SOF interrupt handler
                        if (!ReadWriteAllowed())
                                continue;

                        len -= n;
                        if (ep & TRANSFER_ZERO)
                        {
                                while (n--)
                                        Send8(0);
                        }
                        else if (ep & TRANSFER_PGM)
                        {
                                while (n--)
                                        Send8(pgm_read_byte(data++));
                        }
                        else
                        {
                                while (n--)
                                        Send8(*data++);
                        }

                        if (sendZlp) {
                                ReleaseTX();
                                sendZlp = false;
                        } else if (!ReadWriteAllowed()) { // ...release if buffer is full...
                                ReleaseTX();
                                if (len == 0) sendZlp = true;
                        } else if ((len == 0) && (ep & TRANSFER_RELEASE)) { // ...or if forced with TRANSFER_RELEASE
                                // XXX: TRANSFER_RELEASE is never used can be removed?
                                ReleaseTX();
                        }
                }
        }
        TXLED1;                                 // light the TX LED
        TxLEDPulse = TX_RX_LED_PULSE_MS;
        return r;
}

u8 _initEndpoints[USB_ENDPOINTS] =
{
        0,                      // Control Endpoint
        
        EP_TYPE_INTERRUPT_IN,   // CDC_ENDPOINT_ACM
        EP_TYPE_BULK_OUT,       // CDC_ENDPOINT_OUT
        EP_TYPE_BULK_IN,        // CDC_ENDPOINT_IN

        // Following endpoints are automatically initialized to 0
};

#define EP_SINGLE_64 0x32       // EP0
#define EP_DOUBLE_64 0x36       // Other endpoints
#define EP_SINGLE_16 0x12

static
void InitEP(u8 index, u8 type, u8 size)
{
        UENUM = index;
        UECONX = (1<<EPEN);
        UECFG0X = type;
        UECFG1X = size;
}

static
void InitEndpoints()
{
        for (u8 i = 1; i < sizeof(_initEndpoints) && _initEndpoints[i] != 0; i++)
        {
                UENUM = i;
                UECONX = (1<<EPEN);
                UECFG0X = _initEndpoints[i];
#if USB_EP_SIZE == 16
                UECFG1X = EP_SINGLE_16;
#elif USB_EP_SIZE == 64
                UECFG1X = EP_DOUBLE_64;
#else
#error Unsupported value for USB_EP_SIZE
#endif
        }
        UERST = 0x7E;   // And reset them
        UERST = 0;
}

//      Handle CLASS_INTERFACE requests
static
bool ClassInterfaceRequest(USBSetup& setup)
{
        u8 i = setup.wIndex;

        if (CDC_ACM_INTERFACE == i)
                return CDC_Setup(setup);

#ifdef PLUGGABLE_USB_ENABLED
        return PluggableUSB().setup(setup);
#endif
        return false;
}

static int _cmark;
static int _cend;
void InitControl(int end)
{
        SetEP(0);
        _cmark = 0;
        _cend = end;
}

static
bool SendControl(u8 d)
{
        if (_cmark < _cend)
        {
                if (!WaitForINOrOUT())
                        return false;
                Send8(d);
                if (!((_cmark + 1) & 0x3F))
                        ClearIN();      // Fifo is full, release this packet
        }
        _cmark++;
        return true;
}

//      Clipped by _cmark/_cend
int USB_SendControl(u8 flags, const void* d, int len)
{
        int sent = len;
        const u8* data = (const u8*)d;
        bool pgm = flags & TRANSFER_PGM;
        while (len--)
        {
                u8 c = pgm ? pgm_read_byte(data++) : *data++;
                if (!SendControl(c))
                        return -1;
        }
        return sent;
}

// Send a USB descriptor string. The string is stored in PROGMEM as a
// plain ASCII string but is sent out as UTF-16 with the correct 2-byte
// prefix
static bool USB_SendStringDescriptor(const u8*string_P, u8 string_len, uint8_t flags) {
        SendControl(2 + string_len * 2);
        SendControl(3);
        bool pgm = flags & TRANSFER_PGM;
        for(u8 i = 0; i < string_len; i++) {
                bool r = SendControl(pgm ? pgm_read_byte(&string_P[i]) : string_P[i]);
                r &= SendControl(0); // high byte
                if(!r) {
                        return false;
                }
        }
        return true;
}

//      Does not timeout or cross fifo boundaries
int USB_RecvControl(void* d, int len)
{
        auto length = len;
        while(length)
        {
                // Dont receive more than the USB Control EP has to offer
                // Use fixed 64 because control EP always have 64 bytes even on 16u2.
                auto recvLength = length;
                if(recvLength > 64){
                        recvLength = 64;
                }

                // Write data to fit to the end (not the beginning) of the array
                WaitOUT();
                Recv((u8*)d + len - length, recvLength);
                ClearOUT();
                length -= recvLength;
        }
        return len;
}

static u8 SendInterfaces()
{
        u8 interfaces = 0;

        CDC_GetInterface(&interfaces);

#ifdef PLUGGABLE_USB_ENABLED
        PluggableUSB().getInterface(&interfaces);
#endif

        return interfaces;
}

//      Construct a dynamic configuration descriptor
//      This really needs dynamic endpoint allocation etc
//      TODO
static
bool SendConfiguration(int maxlen)
{
        //      Count and measure interfaces
        InitControl(0);
        u8 interfaces = SendInterfaces();
        ConfigDescriptor config = D_CONFIG(_cmark + sizeof(ConfigDescriptor),interfaces);

        //      Now send them
        InitControl(maxlen);
        USB_SendControl(0,&config,sizeof(ConfigDescriptor));
        SendInterfaces();
        return true;
}

static
bool SendDescriptor(USBSetup& setup)
{
        int ret;
        u8 t = setup.wValueH;
        if (USB_CONFIGURATION_DESCRIPTOR_TYPE == t)
                return SendConfiguration(setup.wLength);

        InitControl(setup.wLength);
#ifdef PLUGGABLE_USB_ENABLED
        ret = PluggableUSB().getDescriptor(setup);
        if (ret != 0) {
                return (ret > 0 ? true : false);
        }
#endif

        const u8* desc_addr = 0;
        if (USB_DEVICE_DESCRIPTOR_TYPE == t)
        {
                desc_addr = (const u8*)&USB_DeviceDescriptorIAD;
        }
        else if (USB_STRING_DESCRIPTOR_TYPE == t)
        {
                if (setup.wValueL == 0) {
                        desc_addr = (const u8*)&STRING_LANGUAGE;
                }
                else if (setup.wValueL == IPRODUCT) {
                        return USB_SendStringDescriptor(STRING_PRODUCT, strlen(USB_PRODUCT), TRANSFER_PGM);
                }
                else if (setup.wValueL == IMANUFACTURER) {
                        return USB_SendStringDescriptor(STRING_MANUFACTURER, strlen(USB_MANUFACTURER), TRANSFER_PGM);
                }
                else if (setup.wValueL == ISERIAL) {
#ifdef PLUGGABLE_USB_ENABLED
                        char name[ISERIAL_MAX_LEN];
                        PluggableUSB().getShortName(name);
                        return USB_SendStringDescriptor((uint8_t*)name, strlen(name), 0);
#endif
                }
                else
                        return false;
        }

        if (desc_addr == 0)
                return false;
        u8 desc_length = pgm_read_byte(desc_addr);

        USB_SendControl(TRANSFER_PGM,desc_addr,desc_length);
        return true;
}

//      Endpoint 0 interrupt
ISR(USB_COM_vect)
{
    SetEP(0);
        if (!ReceivedSetupInt())
                return;

        USBSetup setup;
        Recv((u8*)&setup,8);
        ClearSetupInt();

        u8 requestType = setup.bmRequestType;
        if (requestType & REQUEST_DEVICETOHOST)
                WaitIN();
        else
                ClearIN();

    bool ok = true;
        if (REQUEST_STANDARD == (requestType & REQUEST_TYPE))
        {
                //      Standard Requests
                u8 r = setup.bRequest;
                u16 wValue = setup.wValueL | (setup.wValueH << 8);
                if (GET_STATUS == r)
                {
                        if (requestType == (REQUEST_DEVICETOHOST | REQUEST_STANDARD | REQUEST_DEVICE))
                        {
                                Send8(_usbCurrentStatus);
                                Send8(0);
                        }
                        else
                        {
                                // TODO: handle the HALT state of an endpoint here
                                // see "Figure 9-6. Information Returned by a GetStatus() Request to an Endpoint" in usb_20.pdf for more information
                                Send8(0);
                                Send8(0);
                        }
                }
                else if (CLEAR_FEATURE == r)
                {
                        if((requestType == (REQUEST_HOSTTODEVICE | REQUEST_STANDARD | REQUEST_DEVICE))
                                && (wValue == DEVICE_REMOTE_WAKEUP))
                        {
                                _usbCurrentStatus &= ~FEATURE_REMOTE_WAKEUP_ENABLED;
                        }
                }
                else if (SET_FEATURE == r)
                {
                        if((requestType == (REQUEST_HOSTTODEVICE | REQUEST_STANDARD | REQUEST_DEVICE))
                                && (wValue == DEVICE_REMOTE_WAKEUP))
                        {
                                _usbCurrentStatus |= FEATURE_REMOTE_WAKEUP_ENABLED;
                        }
                }
                else if (SET_ADDRESS == r)
                {
                        WaitIN();
                        UDADDR = setup.wValueL | (1<<ADDEN);
                }
                else if (GET_DESCRIPTOR == r)
                {
                        ok = SendDescriptor(setup);
                }
                else if (SET_DESCRIPTOR == r)
                {
                        ok = false;
                }
                else if (GET_CONFIGURATION == r)
                {
                        Send8(1);
                }
                else if (SET_CONFIGURATION == r)
                {
                        if (REQUEST_DEVICE == (requestType & REQUEST_RECIPIENT))
                        {
                                InitEndpoints();
                                _usbConfiguration = setup.wValueL;
                        } else
                                ok = false;
                }
                else if (GET_INTERFACE == r)
                {
                }
                else if (SET_INTERFACE == r)
                {
                }
        }
        else
        {
                InitControl(setup.wLength);             //      Max length of transfer
                ok = ClassInterfaceRequest(setup);
        }

        if (ok)
                ClearIN();
        else
        {
                Stall();
        }
}

void USB_Flush(u8 ep)
{
        SetEP(ep);
        if (FifoByteCount())
                ReleaseTX();
}

static inline void USB_ClockDisable()
{
#if defined(OTGPADE)
        USBCON = (USBCON & ~(1<<OTGPADE)) | (1<<FRZCLK); // freeze clock and disable VBUS Pad
#else // u2 Series
        USBCON = (1 << FRZCLK); // freeze clock
#endif
        PLLCSR &= ~(1<<PLLE);  // stop PLL
}

static inline void USB_ClockEnable()
{
#if defined(UHWCON)
        UHWCON |= (1<<UVREGE);                  // power internal reg
#endif
        USBCON = (1<<USBE) | (1<<FRZCLK);       // clock frozen, usb enabled

// ATmega32U4
#if defined(PINDIV)
#if F_CPU == 16000000UL
        PLLCSR |= (1<<PINDIV);                   // Need 16 MHz xtal
#elif F_CPU == 8000000UL
        PLLCSR &= ~(1<<PINDIV);                  // Need  8 MHz xtal
#else
#error "Clock rate of F_CPU not supported"
#endif

#elif defined(__AVR_AT90USB82__) || defined(__AVR_AT90USB162__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega8U2__)
        // for the u2 Series the datasheet is confusing. On page 40 its called PINDIV and on page 290 its called PLLP0
#if F_CPU == 16000000UL
        // Need 16 MHz xtal
        PLLCSR |= (1 << PLLP0);
#elif F_CPU == 8000000UL
        // Need 8 MHz xtal
        PLLCSR &= ~(1 << PLLP0);
#endif

// AT90USB646, AT90USB647, AT90USB1286, AT90USB1287
#elif defined(PLLP2)
#if F_CPU == 16000000UL
#if defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
        // For Atmel AT90USB128x only. Do not use with Atmel AT90USB64x.
        PLLCSR = (PLLCSR & ~(1<<PLLP1)) | ((1<<PLLP2) | (1<<PLLP0)); // Need 16 MHz xtal
#elif defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__)
        // For AT90USB64x only. Do not use with AT90USB128x.
        PLLCSR = (PLLCSR & ~(1<<PLLP0)) | ((1<<PLLP2) | (1<<PLLP1)); // Need 16 MHz xtal
#else
#error "USB Chip not supported, please defined method of USB PLL initialization"
#endif
#elif F_CPU == 8000000UL
        // for Atmel AT90USB128x and AT90USB64x
        PLLCSR = (PLLCSR & ~(1<<PLLP2)) | ((1<<PLLP1) | (1<<PLLP0)); // Need 8 MHz xtal
#else
#error "Clock rate of F_CPU not supported"
#endif
#else
#error "USB Chip not supported, please defined method of USB PLL initialization"
#endif

        PLLCSR |= (1<<PLLE);
        while (!(PLLCSR & (1<<PLOCK)))          // wait for lock pll
        {
        }

        // Some tests on specific versions of macosx (10.7.3), reported some
        // strange behaviors when the board is reset using the serial
        // port touch at 1200 bps. This delay fixes this behavior.
        delay(1);
#if defined(OTGPADE)
        USBCON = (USBCON & ~(1<<FRZCLK)) | (1<<OTGPADE);        // start USB clock, enable VBUS Pad
#else
        USBCON &= ~(1 << FRZCLK);       // start USB clock
#endif

#if defined(RSTCPU)
#if defined(LSM)
        UDCON &= ~((1<<RSTCPU) | (1<<LSM) | (1<<RMWKUP) | (1<<DETACH)); // enable attach resistor, set full speed mode
#else // u2 Series
        UDCON &= ~((1 << RSTCPU) | (1 << RMWKUP) | (1 << DETACH));      // enable attach resistor, set full speed mode
#endif
#else
        // AT90USB64x and AT90USB128x don't have RSTCPU
        UDCON &= ~((1<<LSM) | (1<<RMWKUP) | (1<<DETACH));       // enable attach resistor, set full speed mode
#endif
}

//      General interrupt
ISR(USB_GEN_vect)
{
        u8 udint = UDINT;
        UDINT &= ~((1<<EORSTI) | (1<<SOFI)); // clear the IRQ flags for the IRQs which are handled here, except WAKEUPI and SUSPI (see below)

        //      End of Reset
        if (udint & (1<<EORSTI))
        {
                InitEP(0,EP_TYPE_CONTROL,EP_SINGLE_64); // init ep0
                _usbConfiguration = 0;                  // not configured yet
                UEIENX = 1 << RXSTPE;                   // Enable interrupts for ep0
        }

        //      Start of Frame - happens every millisecond so we use it for TX and RX LED one-shot timing, too
        if (udint & (1<<SOFI))
        {
                USB_Flush(CDC_TX);                              // Send a tx frame if found
                
                // check whether the one-shot period has elapsed.  if so, turn off the LED
                if (TxLEDPulse && !(--TxLEDPulse))
                        TXLED0;
                if (RxLEDPulse && !(--RxLEDPulse))
                        RXLED0;
        }

        // the WAKEUPI interrupt is triggered as soon as there are non-idle patterns on the data
        // lines. Thus, the WAKEUPI interrupt can occur even if the controller is not in the "suspend" mode.
        // Therefore the we enable it only when USB is suspended
        if (udint & (1<<WAKEUPI))
        {
                UDIEN = (UDIEN & ~(1<<WAKEUPE)) | (1<<SUSPE); // Disable interrupts for WAKEUP and enable interrupts for SUSPEND

                //TODO
                // WAKEUPI shall be cleared by software (USB clock inputs must be enabled before).
                //USB_ClockEnable();
                UDINT &= ~(1<<WAKEUPI);
                _usbSuspendState = (_usbSuspendState & ~(1<<SUSPI)) | (1<<WAKEUPI);
        }
        else if (udint & (1<<SUSPI)) // only one of the WAKEUPI / SUSPI bits can be active at time
        {
                UDIEN = (UDIEN & ~(1<<SUSPE)) | (1<<WAKEUPE); // Disable interrupts for SUSPEND and enable interrupts for WAKEUP

                //TODO
                //USB_ClockDisable();

                UDINT &= ~((1<<WAKEUPI) | (1<<SUSPI)); // clear any already pending WAKEUP IRQs and the SUSPI request
                _usbSuspendState = (_usbSuspendState & ~(1<<WAKEUPI)) | (1<<SUSPI);
        }
}

//      VBUS or counting frames
//      Any frame counting?
u8 USBConnected()
{
        u8 f = UDFNUML;
        delay(3);
        return f != UDFNUML;
}

//=======================================================================
//=======================================================================

USBDevice_ USBDevice;

USBDevice_::USBDevice_()
{
}

void USBDevice_::attach()
{
        _usbConfiguration = 0;
        _usbCurrentStatus = 0;
        _usbSuspendState = 0;
        USB_ClockEnable();

        UDINT &= ~((1<<WAKEUPI) | (1<<SUSPI)); // clear already pending WAKEUP / SUSPEND requests
        UDIEN = (1<<EORSTE) | (1<<SOFE) | (1<<SUSPE);   // Enable interrupts for EOR (End of Reset), SOF (start of frame) and SUSPEND
        
        TX_RX_LED_INIT;

#if MAGIC_KEY_POS != (RAMEND-1)
        if (pgm_read_word(FLASHEND - 1) == NEW_LUFA_SIGNATURE) {
                _updatedLUFAbootloader = true;
        }
#endif
}

void USBDevice_::detach()
{
}

//      Check for interrupts
//      TODO: VBUS detection
bool USBDevice_::configured()
{
        return _usbConfiguration;
}

void USBDevice_::poll()
{
}

bool USBDevice_::wakeupHost()
{
        // clear any previous wakeup request which might have been set but could be processed at that time
        // e.g. because the host was not suspended at that time
        UDCON &= ~(1 << RMWKUP);

        if(!(UDCON & (1 << RMWKUP))
          && (_usbSuspendState & (1<<SUSPI))
          && (_usbCurrentStatus & FEATURE_REMOTE_WAKEUP_ENABLED))
        {
                // This short version will only work, when the device has not been suspended. Currently the
                // Arduino core doesn't handle SUSPEND at all, so this is ok.
                USB_ClockEnable();
                UDCON |= (1 << RMWKUP); // send the wakeup request
                return true;
        }

        return false;
}

#endif /* if defined(USBCON) */