/* Name: usbdrv.c* Project: AVR USB driver* Author: Christian Starkjohann* Creation Date: 2004-12-29* Tabsize: 4* Copyright: (c) 2005 by OBJECTIVE DEVELOPMENT Software GmbH* License: GNU GPL v2 (see License.txt) or proprietary (CommercialLicense.txt)* This Revision: $Id: usbdrv.c,v 1.3 2007/06/07 13:53:47 harbaum Exp $*/#include "iarcompat.h"#ifndef __IAR_SYSTEMS_ICC__# include <avr/io.h># include <avr/pgmspace.h>#endif#include "usbdrv.h"#include "oddebug.h"/*General Description:This module implements the C-part of the USB driver. See usbdrv.h for adocumentation of the entire driver.*/#ifndef IAR_SECTION#define IAR_SECTION(arg)#define __no_init#endif/* The macro IAR_SECTION is a hack to allow IAR-cc compatibility. On gcc, it* is defined to nothing. __no_init is required on IAR.*//* ------------------------------------------------------------------------- *//* raw USB registers / interface to assembler code: */uchar usbRxBuf[2*USB_BUFSIZE]; /* raw RX buffer: PID, 8 bytes data, 2 bytes CRC */uchar usbInputBufOffset; /* offset in usbRxBuf used for low level receiving */uchar usbDeviceAddr; /* assigned during enumeration, defaults to 0 */uchar usbNewDeviceAddr; /* device ID which should be set after status phase */uchar usbConfiguration; /* currently selected configuration. Administered by driver, but not used */volatile schar usbRxLen; /* = 0; number of bytes in usbRxBuf; 0 means free, -1 for flow control */uchar usbCurrentTok; /* last token received, if more than 1 rx endpoint: MSb=endpoint */uchar usbRxToken; /* token for data we received; if more than 1 rx endpoint: MSb=endpoint */uchar usbMsgLen = 0xff; /* remaining number of bytes, no msg to send if -1 (see usbMsgPtr) */volatile uchar usbTxLen = USBPID_NAK; /* number of bytes to transmit with next IN token or handshake token */uchar usbTxBuf[USB_BUFSIZE];/* data to transmit with next IN, free if usbTxLen contains handshake token */#if USB_CFG_HAVE_INTRIN_ENDPOINTvolatile uchar usbTxLen1 = USBPID_NAK; /* TX count for endpoint 1 */uchar usbTxBuf1[USB_BUFSIZE]; /* TX data for endpoint 1 */#if USB_CFG_HAVE_INTRIN_ENDPOINT3volatile uchar usbTxLen3 = USBPID_NAK; /* TX count for endpoint 1 */uchar usbTxBuf3[USB_BUFSIZE]; /* TX data for endpoint 1 */#endif#endif/* USB status registers / not shared with asm code */uchar *usbMsgPtr; /* data to transmit next -- ROM or RAM address */static uchar usbMsgFlags; /* flag values see below */#define USB_FLG_TX_PACKET (1<<0)/* Leave free 6 bits after TX_PACKET. This way we can increment usbMsgFlags to toggle TX_PACKET */#define USB_FLG_MSGPTR_IS_ROM (1<<6)#define USB_FLG_USE_DEFAULT_RW (1<<7)/*optimizing hints:- do not post/pre inc/dec integer values in operations- assign value of PRG_RDB() to register variables and don't use side effects in arg- use narrow scope for variables which should be in X/Y/Z register- assign char sized expressions to variables to force 8 bit arithmetics*//* ------------------------------------------------------------------------- */#if USB_CFG_DESCR_PROPS_STRINGS == 0#if USB_CFG_DESCR_PROPS_STRING_0 == 0#undef USB_CFG_DESCR_PROPS_STRING_0#define USB_CFG_DESCR_PROPS_STRING_0 sizeof(usbDescriptorString0)PROGMEM char usbDescriptorString0[] = { /* language descriptor */4, /* sizeof(usbDescriptorString0): length of descriptor in bytes */3, /* descriptor type */0x09, 0x04, /* language index (0x0409 = US-English) */};#endif#if USB_CFG_DESCR_PROPS_STRING_VENDOR == 0 && USB_CFG_VENDOR_NAME_LEN#undef USB_CFG_DESCR_PROPS_STRING_VENDOR#define USB_CFG_DESCR_PROPS_STRING_VENDOR sizeof(usbDescriptorStringVendor)PROGMEM int usbDescriptorStringVendor[] = {USB_STRING_DESCRIPTOR_HEADER(USB_CFG_VENDOR_NAME_LEN),USB_CFG_VENDOR_NAME};#endif#if USB_CFG_DESCR_PROPS_STRING_DEVICE == 0 && USB_CFG_DEVICE_NAME_LEN#undef USB_CFG_DESCR_PROPS_STRING_DEVICE#define USB_CFG_DESCR_PROPS_STRING_DEVICE sizeof(usbDescriptorStringDevice)PROGMEM int usbDescriptorStringDevice[] = {USB_STRING_DESCRIPTOR_HEADER(USB_CFG_DEVICE_NAME_LEN),USB_CFG_DEVICE_NAME};#endif#if USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER == 0 && USB_CFG_SERIAL_NUMBER_LEN#undef USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER#define USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER sizeof(usbDescriptorStringSerialNumber)PROGMEM int usbDescriptorStringSerialNumber[] = {USB_STRING_DESCRIPTOR_HEADER(USB_CFG_SERIAL_NUMBER_LEN),USB_CFG_SERIAL_NUMBER};#endif#endif /* USB_CFG_DESCR_PROPS_STRINGS == 0 */#if USB_CFG_DESCR_PROPS_DEVICE == 0#undef USB_CFG_DESCR_PROPS_DEVICE#define USB_CFG_DESCR_PROPS_DEVICE sizeof(usbDescriptorDevice)PROGMEM char usbDescriptorDevice[] = { /* USB device descriptor */18, /* sizeof(usbDescriptorDevice): length of descriptor in bytes */USBDESCR_DEVICE, /* descriptor type */0x10, 0x01, /* USB version supported */USB_CFG_DEVICE_CLASS,USB_CFG_DEVICE_SUBCLASS,0, /* protocol */8, /* max packet size */USB_CFG_VENDOR_ID, /* 2 bytes */USB_CFG_DEVICE_ID, /* 2 bytes */USB_CFG_DEVICE_VERSION, /* 2 bytes */USB_CFG_DESCR_PROPS_STRING_VENDOR != 0 ? 1 : 0, /* manufacturer string index */USB_CFG_DESCR_PROPS_STRING_DEVICE != 0 ? 2 : 0, /* product string index */USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER != 0 ? 3 : 0, /* serial number string index */1, /* number of configurations */};#endif#if USB_CFG_DESCR_PROPS_HID_REPORT != 0 && USB_CFG_DESCR_PROPS_HID == 0#undef USB_CFG_DESCR_PROPS_HID#define USB_CFG_DESCR_PROPS_HID 9 /* length of HID descriptor in config descriptor below */#endif#if USB_CFG_DESCR_PROPS_CONFIGURATION == 0#undef USB_CFG_DESCR_PROPS_CONFIGURATION#define USB_CFG_DESCR_PROPS_CONFIGURATION sizeof(usbDescriptorConfiguration)PROGMEM char usbDescriptorConfiguration[] = { /* USB configuration descriptor */9, /* sizeof(usbDescriptorConfiguration): length of descriptor in bytes */USBDESCR_CONFIG, /* descriptor type */18 + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT + (USB_CFG_DESCR_PROPS_HID & 0xff), 0,/* total length of data returned (including inlined descriptors) */1, /* number of interfaces in this configuration */1, /* index of this configuration */0, /* configuration name string index */#if USB_CFG_IS_SELF_POWEREDUSBATTR_SELFPOWER, /* attributes */#elseUSBATTR_BUSPOWER, /* attributes */#endifUSB_CFG_MAX_BUS_POWER/2, /* max USB current in 2mA units *//* interface descriptor follows inline: */9, /* sizeof(usbDescrInterface): length of descriptor in bytes */USBDESCR_INTERFACE, /* descriptor type */0, /* index of this interface */0, /* alternate setting for this interface */USB_CFG_HAVE_INTRIN_ENDPOINT, /* endpoints excl 0: number of endpoint descriptors to follow */USB_CFG_INTERFACE_CLASS,USB_CFG_INTERFACE_SUBCLASS,USB_CFG_INTERFACE_PROTOCOL,0, /* string index for interface */#if (USB_CFG_DESCR_PROPS_HID & 0xff) /* HID descriptor */9, /* sizeof(usbDescrHID): length of descriptor in bytes */USBDESCR_HID, /* descriptor type: HID */0x01, 0x01, /* BCD representation of HID version */0x00, /* target country code */0x01, /* number of HID Report (or other HID class) Descriptor infos to follow */0x22, /* descriptor type: report */USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH, 0, /* total length of report descriptor */#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT /* endpoint descriptor for endpoint 1 */7, /* sizeof(usbDescrEndpoint) */USBDESCR_ENDPOINT, /* descriptor type = endpoint */0x81, /* IN endpoint number 1 */0x03, /* attrib: Interrupt endpoint */8, 0, /* maximum packet size */USB_CFG_INTR_POLL_INTERVAL, /* in ms */#endif};#endif/* We don't use prog_int or prog_int16_t for compatibility with various libc* versions. Here's an other compatibility hack:*/#ifndef PRG_RDB#define PRG_RDB(addr) pgm_read_byte(addr)#endiftypedef union{unsigned word;uchar *ptr;uchar bytes[2];}converter_t;/* We use this union to do type conversions. This is better optimized than* type casts in gcc 3.4.3 and much better than using bit shifts to build* ints from chars. Byte ordering is not a problem on an 8 bit platform.*//* ------------------------------------------------------------------------- */#if USB_CFG_HAVE_INTRIN_ENDPOINTvoid usbSetInterrupt(uchar *data, uchar len){uchar *p, i;#if USB_CFG_IMPLEMENT_HALTif(usbTxLen1 == USBPID_STALL)return;#endif#if 0 /* No runtime checks! Caller is responsible for valid data! */if(len > 8) /* interrupt transfers are limited to 8 bytes */len = 8;#endifif(usbTxLen1 & 0x10){ /* packet buffer was empty */usbTxBuf1[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* toggle token */}else{usbTxLen1 = USBPID_NAK; /* avoid sending outdated (overwritten) interrupt data */}p = usbTxBuf1 + 1;for(i=len;i--;)*p++ = *data++;usbCrc16Append(&usbTxBuf1[1], len);usbTxLen1 = len + 4; /* len must be given including sync byte */DBG2(0x21, usbTxBuf1, len + 3);}#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT3void usbSetInterrupt3(uchar *data, uchar len){uchar *p, i;if(usbTxLen3 & 0x10){ /* packet buffer was empty */usbTxBuf3[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* toggle token */}else{usbTxLen3 = USBPID_NAK; /* avoid sending outdated (overwritten) interrupt data */}p = usbTxBuf3 + 1;for(i=len;i--;)*p++ = *data++;usbCrc16Append(&usbTxBuf3[1], len);usbTxLen3 = len + 4; /* len must be given including sync byte */DBG2(0x23, usbTxBuf3, len + 3);}#endifstatic uchar usbRead(uchar *data, uchar len){#if USB_CFG_IMPLEMENT_FN_READif(usbMsgFlags & USB_FLG_USE_DEFAULT_RW){#endifuchar i = len, *r = usbMsgPtr;if(usbMsgFlags & USB_FLG_MSGPTR_IS_ROM){ /* ROM data */while(i--){uchar c = PRG_RDB(r); /* assign to char size variable to enforce byte ops */*data++ = c;r++;}}else{ /* RAM data */while(i--)*data++ = *r++;}usbMsgPtr = r;return len;#if USB_CFG_IMPLEMENT_FN_READ}else{if(len != 0) /* don't bother app with 0 sized reads */return usbFunctionRead(data, len);return 0;}#endif}#define GET_DESCRIPTOR(cfgProp, staticName) \if(cfgProp){ \if((cfgProp) & USB_PROP_IS_RAM) \flags &= ~USB_FLG_MSGPTR_IS_ROM; \if((cfgProp) & USB_PROP_IS_DYNAMIC){ \replyLen = usbFunctionDescriptor(rq); \}else{ \replyData = (uchar *)(staticName); \SET_REPLY_LEN((cfgProp) & 0xff); \} \}/* We use if() instead of #if in the macro above because #if can't be used* in macros and the compiler optimizes constant conditions anyway.*//* Don't make this function static to avoid inlining.* The entire function would become too large and exceed the range of* relative jumps.* 2006-02-25: Either gcc 3.4.3 is better than the gcc used when the comment* above was written, or other parts of the code have changed. We now get* better results with an inlined function. Test condition: PowerSwitch code.*/static void usbProcessRx(uchar *data, uchar len){usbRequest_t *rq = (void *)data;uchar replyLen = 0, flags = USB_FLG_USE_DEFAULT_RW;/* We use if() cascades because the compare is done byte-wise while switch()* is int-based. The if() cascades are therefore more efficient.*//* usbRxToken can be:* 0x2d 00101101 (USBPID_SETUP for endpoint 0)* 0xe1 11100001 (USBPID_OUT for endpoint 0)* 0xff 11111111 (USBPID_OUT for endpoint 1)*/DBG2(0x10 + ((usbRxToken >> 1) & 3), data, len); /* SETUP0=12; OUT0=10; OUT1=13 */#if USB_CFG_IMPLEMENT_FN_WRITEOUTif(usbRxToken == 0xff){usbFunctionWriteOut(data, len);return; /* no reply expected, hence no usbMsgPtr, usbMsgFlags, usbMsgLen set */}#endifif(usbRxToken == (uchar)USBPID_SETUP){usbTxLen = USBPID_NAK; /* abort pending transmit */if(len == 8){ /* Setup size must be always 8 bytes. Ignore otherwise. */uchar type = rq->bmRequestType & USBRQ_TYPE_MASK;if(type == USBRQ_TYPE_STANDARD){#define SET_REPLY_LEN(len) replyLen = (len); usbMsgPtr = replyData/* This macro ensures that replyLen and usbMsgPtr are always set in the same way.* That allows optimization of common code in if() branches */uchar *replyData = usbTxBuf + 9; /* there is 3 bytes free space at the end of the buffer */replyData[0] = 0; /* common to USBRQ_GET_STATUS and USBRQ_GET_INTERFACE */if(rq->bRequest == USBRQ_GET_STATUS){ /* 0 */uchar __attribute__((__unused__)) recipient = rq->bmRequestType & USBRQ_RCPT_MASK; /* assign arith ops to variables to enforce byte size */#if USB_CFG_IS_SELF_POWEREDif(recipient == USBRQ_RCPT_DEVICE)replyData[0] = USB_CFG_IS_SELF_POWERED;#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT && USB_CFG_IMPLEMENT_HALTif(recipient == USBRQ_RCPT_ENDPOINT && rq->wIndex.bytes[0] == 0x81) /* request status for endpoint 1 */replyData[0] = usbTxLen1 == USBPID_STALL;#endifreplyData[1] = 0;SET_REPLY_LEN(2);}else if(rq->bRequest == USBRQ_SET_ADDRESS){ /* 5 */usbNewDeviceAddr = rq->wValue.bytes[0];}else if(rq->bRequest == USBRQ_GET_DESCRIPTOR){ /* 6 */flags = USB_FLG_MSGPTR_IS_ROM | USB_FLG_USE_DEFAULT_RW;if(rq->wValue.bytes[1] == USBDESCR_DEVICE){ /* 1 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_DEVICE, usbDescriptorDevice)}else if(rq->wValue.bytes[1] == USBDESCR_CONFIG){ /* 2 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_CONFIGURATION, usbDescriptorConfiguration)}else if(rq->wValue.bytes[1] == USBDESCR_STRING){ /* 3 */#if USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMICif(USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_RAM)flags &= ~USB_FLG_MSGPTR_IS_ROM;replyLen = usbFunctionDescriptor(rq);#else /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */if(rq->wValue.bytes[0] == 0){ /* descriptor index */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_0, usbDescriptorString0)}else if(rq->wValue.bytes[0] == 1){GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_VENDOR, usbDescriptorStringVendor)}else if(rq->wValue.bytes[0] == 2){GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_DEVICE, usbDescriptorStringDevice)}else if(rq->wValue.bytes[0] == 3){GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER, usbDescriptorStringSerialNumber)}else if(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){replyLen = usbFunctionDescriptor(rq);}#endif /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */}else if(rq->wValue.bytes[1] == USBDESCR_HID){ /* 0x21 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID, usbDescriptorConfiguration + 18)}else if(rq->wValue.bytes[1] == USBDESCR_HID_REPORT){ /* 0x22 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID_REPORT, usbDescriptorHidReport)}else if(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){replyLen = usbFunctionDescriptor(rq);}}else if(rq->bRequest == USBRQ_GET_CONFIGURATION){ /* 8 */replyData = &usbConfiguration; /* send current configuration value */SET_REPLY_LEN(1);}else if(rq->bRequest == USBRQ_SET_CONFIGURATION){ /* 9 */usbConfiguration = rq->wValue.bytes[0];#if USB_CFG_IMPLEMENT_HALTusbTxLen1 = USBPID_NAK;#endif}else if(rq->bRequest == USBRQ_GET_INTERFACE){ /* 10 */SET_REPLY_LEN(1);#if USB_CFG_HAVE_INTRIN_ENDPOINT}else if(rq->bRequest == USBRQ_SET_INTERFACE){ /* 11 */USB_SET_DATATOKEN1(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# if USB_CFG_HAVE_INTRIN_ENDPOINT3USB_SET_DATATOKEN3(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# endif# if USB_CFG_IMPLEMENT_HALTusbTxLen1 = USBPID_NAK;}else if(rq->bRequest == USBRQ_CLEAR_FEATURE || rq->bRequest == USBRQ_SET_FEATURE){ /* 1|3 */if(rq->wValue.bytes[0] == 0 && rq->wIndex.bytes[0] == 0x81){ /* feature 0 == HALT for endpoint == 1 */usbTxLen1 = rq->bRequest == USBRQ_CLEAR_FEATURE ? USBPID_NAK : USBPID_STALL;USB_SET_DATATOKEN1(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# if USB_CFG_HAVE_INTRIN_ENDPOINT3USB_SET_DATATOKEN3(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# endif}# endif#endif}else{/* the following requests can be ignored, send default reply *//* 1: CLEAR_FEATURE, 3: SET_FEATURE, 7: SET_DESCRIPTOR *//* 12: SYNCH_FRAME */}#undef SET_REPLY_LEN}else{ /* not a standard request -- must be vendor or class request */replyLen = usbFunctionSetup(data);}#if USB_CFG_IMPLEMENT_FN_READ || USB_CFG_IMPLEMENT_FN_WRITEif(replyLen == 0xff){ /* use user-supplied read/write function */if((rq->bmRequestType & USBRQ_DIR_MASK) == USBRQ_DIR_DEVICE_TO_HOST){replyLen = rq->wLength.bytes[0]; /* IN transfers only */}flags &= ~USB_FLG_USE_DEFAULT_RW; /* we have no valid msg, use user supplied read/write functions */}else /* The 'else' prevents that we limit a replyLen of 0xff to the maximum transfer len. */#endifif(!rq->wLength.bytes[1] && replyLen > rq->wLength.bytes[0]) /* limit length to max */replyLen = rq->wLength.bytes[0];}/* make sure that data packets which are sent as ACK to an OUT transfer are always zero sized */}else{ /* DATA packet from out request */#if USB_CFG_IMPLEMENT_FN_WRITEif(!(usbMsgFlags & USB_FLG_USE_DEFAULT_RW)){uchar rval = usbFunctionWrite(data, len);replyLen = 0xff;if(rval == 0xff){ /* an error occurred */usbMsgLen = 0xff; /* cancel potentially pending data packet for ACK */usbTxLen = USBPID_STALL;}else if(rval != 0){ /* This was the final package */replyLen = 0; /* answer with a zero-sized data packet */}flags = 0; /* start with a DATA1 package, stay with user supplied write() function */}#endif}usbMsgFlags = flags;usbMsgLen = replyLen;}/* ------------------------------------------------------------------------- */static void usbBuildTxBlock(void){uchar wantLen, len, txLen, token;wantLen = usbMsgLen;if(wantLen > 8)wantLen = 8;usbMsgLen -= wantLen;token = USBPID_DATA1;if(usbMsgFlags & USB_FLG_TX_PACKET)token = USBPID_DATA0;usbMsgFlags++;len = usbRead(usbTxBuf + 1, wantLen);if(len <= 8){ /* valid data packet */usbCrc16Append(&usbTxBuf[1], len);txLen = len + 4; /* length including sync byte */if(len < 8) /* a partial package identifies end of message */usbMsgLen = 0xff;}else{txLen = USBPID_STALL; /* stall the endpoint */usbMsgLen = 0xff;}usbTxBuf[0] = token;usbTxLen = txLen;DBG2(0x20, usbTxBuf, txLen-1);}static inline uchar isNotSE0(void){uchar rval;/* We want to do* return (USBIN & USBMASK);* here, but the compiler does int-expansion acrobatics.* We can avoid this by assigning to a char-sized variable.*/rval = USBIN & USBMASK;return rval;}/* ------------------------------------------------------------------------- */void usbPoll(void){uchar len, i;if((len = usbRxLen) > 0){/* We could check CRC16 here -- but ACK has already been sent anyway. If you* need data integrity checks with this driver, check the CRC in your app* code and report errors back to the host. Since the ACK was already sent,* retries must be handled on application level.* unsigned crc = usbCrc16(buffer + 1, usbRxLen - 3);*/usbProcessRx(usbRxBuf + USB_BUFSIZE + 1 - usbInputBufOffset, len - 3);#if USB_CFG_HAVE_FLOWCONTROLif(usbRxLen > 0) /* only mark as available if not inactivated */usbRxLen = 0;#elseusbRxLen = 0; /* mark rx buffer as available */#endif}if(usbTxLen & 0x10){ /* transmit system idle */if(usbMsgLen != 0xff){ /* transmit data pending? */usbBuildTxBlock();}}for(i = 10; i > 0; i--){if(isNotSE0())break;}if(i == 0){ /* RESET condition, called multiple times during reset */usbNewDeviceAddr = 0;usbDeviceAddr = 0;#if USB_CFG_IMPLEMENT_HALTusbTxLen1 = USBPID_NAK;#if USB_CFG_HAVE_INTRIN_ENDPOINT3usbTxLen3 = USBPID_NAK;#endif#endifDBG1(0xff, 0, 0);}}/* ------------------------------------------------------------------------- */void usbInit(void){#if USB_INTR_CFG_SET != 0USB_INTR_CFG |= USB_INTR_CFG_SET;#endif#if USB_INTR_CFG_CLR != 0USB_INTR_CFG &= ~(USB_INTR_CFG_CLR);#endifUSB_INTR_ENABLE |= (1 << USB_INTR_ENABLE_BIT);#if USB_CFG_HAVE_INTRIN_ENDPOINTUSB_SET_DATATOKEN1(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# if USB_CFG_HAVE_INTRIN_ENDPOINT3USB_SET_DATATOKEN3(USBPID_DATA0); /* reset data toggling for interrupt endpoint */# endif#endif}/* ------------------------------------------------------------------------- */