USBCore.cpp

/* 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)

/** Pulse generation counters to keep track of the number of milliseconds remaining for each pulse type */
#define TX_RX_LED_PULSE_MS 100
volatile u8 TxLEDPulse; /**< Milliseconds remaining for data Tx LED pulse */
volatile u8 RxLEDPulse; /**< Milliseconds remaining for data Rx LED pulse */

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

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) */