/* Name: usbdrv.c* Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers* 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), GNU GPL v3 or proprietary (CommercialLicense.txt)*/#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.*//* ------------------------------------------------------------------------- *//* 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 or endpoint number for last OUT token if != 0 */uchar usbRxToken; /* token for data we received; or endpont number for last OUT */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_COUNT_SOFvolatile uchar usbSofCount; /* incremented by assembler module every SOF */#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODEusbTxStatus_t usbTxStatus1;# if USB_CFG_HAVE_INTRIN_ENDPOINT3usbTxStatus_t usbTxStatus3;# endif#endif#if USB_CFG_CHECK_DATA_TOGGLINGuchar usbCurrentDataToken;/* when we check data toggling to ignore duplicate packets */#endif/* USB status registers / not shared with asm code */usbMsgPtr_t usbMsgPtr; /* data to transmit next -- ROM or RAM address */static usbMsgLen_t usbMsgLen = USB_NO_MSG; /* remaining number of bytes */static uchar usbMsgFlags; /* flag values see below */#define USB_FLG_MSGPTR_IS_ROM (1<<6)#define USB_FLG_USE_USER_RW (1<<7)/*optimizing hints:- do not post/pre inc/dec integer values in operations- assign value of USB_READ_FLASH() 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*//* -------------------------- String Descriptors --------------------------- */#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 const 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 const int usbDescriptorStringVendor[] = {USB_STRING_DESCRIPTOR_HEADER(USB_CFG_VENDOR_NAME_LEN),USB_CFG_VENDOR_NAME};#endif#if USB_CFG_DESCR_PROPS_STRING_PRODUCT == 0 && USB_CFG_DEVICE_NAME_LEN#undef USB_CFG_DESCR_PROPS_STRING_PRODUCT#define USB_CFG_DESCR_PROPS_STRING_PRODUCT sizeof(usbDescriptorStringDevice)PROGMEM const 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 const int usbDescriptorStringSerialNumber[] = {USB_STRING_DESCRIPTOR_HEADER(USB_CFG_SERIAL_NUMBER_LEN),USB_CFG_SERIAL_NUMBER};#endif#endif /* USB_CFG_DESCR_PROPS_STRINGS == 0 *//* --------------------------- Device Descriptor --------------------------- */#if USB_CFG_DESCR_PROPS_DEVICE == 0#undef USB_CFG_DESCR_PROPS_DEVICE#define USB_CFG_DESCR_PROPS_DEVICE sizeof(usbDescriptorDevice)PROGMEM const 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 *//* the following two casts affect the first byte of the constant only, but* that's sufficient to avoid a warning with the default values.*/(char)USB_CFG_VENDOR_ID,/* 2 bytes */(char)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_PRODUCT != 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/* ----------------------- Configuration Descriptor ------------------------ */#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 const char usbDescriptorConfiguration[] = { /* USB configuration descriptor */9, /* sizeof(usbDescriptorConfiguration): length of descriptor in bytes */USBDESCR_CONFIG, /* descriptor type */18 + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT3 +(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_POWERED(1 << 7) | USBATTR_SELFPOWER, /* attributes */#else(1 << 7), /* 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 + USB_CFG_HAVE_INTRIN_ENDPOINT3, /* 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 */(char)0x81, /* IN endpoint number 1 */0x03, /* attrib: Interrupt endpoint */8, 0, /* maximum packet size */USB_CFG_INTR_POLL_INTERVAL, /* in ms */#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT3 /* endpoint descriptor for endpoint 3 */7, /* sizeof(usbDescrEndpoint) */USBDESCR_ENDPOINT, /* descriptor type = endpoint */(char)(0x80 | USB_CFG_EP3_NUMBER), /* IN endpoint number 3 */0x03, /* attrib: Interrupt endpoint */8, 0, /* maximum packet size */USB_CFG_INTR_POLL_INTERVAL, /* in ms */#endif};#endif/* ------------------------------------------------------------------------- */static inline void usbResetDataToggling(void){#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODEUSB_SET_DATATOKEN1(USB_INITIAL_DATATOKEN); /* reset data toggling for interrupt endpoint */# if USB_CFG_HAVE_INTRIN_ENDPOINT3USB_SET_DATATOKEN3(USB_INITIAL_DATATOKEN); /* reset data toggling for interrupt endpoint */# endif#endif}static inline void usbResetStall(void){#if USB_CFG_IMPLEMENT_HALT && USB_CFG_HAVE_INTRIN_ENDPOINTusbTxLen1 = USBPID_NAK;#if USB_CFG_HAVE_INTRIN_ENDPOINT3usbTxLen3 = USBPID_NAK;#endif#endif}/* ------------------------------------------------------------------------- */#if !USB_CFG_SUPPRESS_INTR_CODE#if USB_CFG_HAVE_INTRIN_ENDPOINTstatic void usbGenericSetInterrupt(uchar *data, uchar len, usbTxStatus_t *txStatus){uchar *p;char i;#if USB_CFG_IMPLEMENT_HALTif(usbTxLen1 == USBPID_STALL)return;#endifif(txStatus->len & 0x10){ /* packet buffer was empty */txStatus->buffer[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* toggle token */}else{txStatus->len = USBPID_NAK; /* avoid sending outdated (overwritten) interrupt data */}p = txStatus->buffer + 1;i = len;do{ /* if len == 0, we still copy 1 byte, but that's no problem */*p++ = *data++;}while(--i > 0); /* loop control at the end is 2 bytes shorter than at beginning */usbCrc16Append(&txStatus->buffer[1], len);txStatus->len = len + 4; /* len must be given including sync byte */DBG2(0x21 + (((int)txStatus >> 3) & 3), txStatus->buffer, len + 3);}USB_PUBLIC void usbSetInterrupt(uchar *data, uchar len){usbGenericSetInterrupt(data, len, &usbTxStatus1);}#endif#if USB_CFG_HAVE_INTRIN_ENDPOINT3USB_PUBLIC void usbSetInterrupt3(uchar *data, uchar len){usbGenericSetInterrupt(data, len, &usbTxStatus3);}#endif#endif /* USB_CFG_SUPPRESS_INTR_CODE *//* ------------------ utilities for code following below ------------------- *//* Use defines for the switch statement so that we can choose between an* if()else if() and a switch/case based implementation. switch() is more* efficient for a LARGE set of sequential choices, if() is better in all other* cases.*/#if USB_CFG_USE_SWITCH_STATEMENT# define SWITCH_START(cmd) switch(cmd){{# define SWITCH_CASE(value) }break; case (value):{# define SWITCH_CASE2(v1,v2) }break; case (v1): case(v2):{# define SWITCH_CASE3(v1,v2,v3) }break; case (v1): case(v2): case(v3):{# define SWITCH_DEFAULT }break; default:{# define SWITCH_END }}#else# define SWITCH_START(cmd) {uchar _cmd = cmd; if(0){# define SWITCH_CASE(value) }else if(_cmd == (value)){# define SWITCH_CASE2(v1,v2) }else if(_cmd == (v1) || _cmd == (v2)){# define SWITCH_CASE3(v1,v2,v3) }else if(_cmd == (v1) || _cmd == (v2) || (_cmd == v3)){# define SWITCH_DEFAULT }else{# define SWITCH_END }}#endif#ifndef USB_RX_USER_HOOK#define USB_RX_USER_HOOK(data, len)#endif#ifndef USB_SET_ADDRESS_HOOK#define USB_SET_ADDRESS_HOOK()#endif/* ------------------------------------------------------------------------- *//* We use if() instead of #if in the macro below because #if can't be used* in macros and the compiler optimizes constant conditions anyway.* This may cause problems with undefined symbols if compiled without* optimizing!*/#define GET_DESCRIPTOR(cfgProp, staticName) \if(cfgProp){ \if((cfgProp) & USB_PROP_IS_RAM) \flags = 0; \if((cfgProp) & USB_PROP_IS_DYNAMIC){ \len = usbFunctionDescriptor(rq); \}else{ \len = USB_PROP_LENGTH(cfgProp); \usbMsgPtr = (usbMsgPtr_t)(staticName); \} \}/* usbDriverDescriptor() is similar to usbFunctionDescriptor(), but used* internally for all types of descriptors.*/static inline usbMsgLen_t usbDriverDescriptor(usbRequest_t *rq){usbMsgLen_t len = 0;uchar flags = USB_FLG_MSGPTR_IS_ROM;SWITCH_START(rq->wValue.bytes[1])SWITCH_CASE(USBDESCR_DEVICE) /* 1 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_DEVICE, usbDescriptorDevice)SWITCH_CASE(USBDESCR_CONFIG) /* 2 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_CONFIGURATION, usbDescriptorConfiguration)SWITCH_CASE(USBDESCR_STRING) /* 3 */#if USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMICif(USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_RAM)flags = 0;len = usbFunctionDescriptor(rq);#else /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */SWITCH_START(rq->wValue.bytes[0])SWITCH_CASE(0)GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_0, usbDescriptorString0)SWITCH_CASE(1)GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_VENDOR, usbDescriptorStringVendor)SWITCH_CASE(2)GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_PRODUCT, usbDescriptorStringDevice)SWITCH_CASE(3)GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_STRING_SERIAL_NUMBER, usbDescriptorStringSerialNumber)SWITCH_DEFAULTif(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){len = usbFunctionDescriptor(rq);}SWITCH_END#endif /* USB_CFG_DESCR_PROPS_STRINGS & USB_PROP_IS_DYNAMIC */#if USB_CFG_DESCR_PROPS_HID_REPORT /* only support HID descriptors if enabled */SWITCH_CASE(USBDESCR_HID) /* 0x21 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID, usbDescriptorConfiguration + 18)SWITCH_CASE(USBDESCR_HID_REPORT)/* 0x22 */GET_DESCRIPTOR(USB_CFG_DESCR_PROPS_HID_REPORT, usbDescriptorHidReport)#endifSWITCH_DEFAULTif(USB_CFG_DESCR_PROPS_UNKNOWN & USB_PROP_IS_DYNAMIC){len = usbFunctionDescriptor(rq);}SWITCH_ENDusbMsgFlags = flags;return len;}/* ------------------------------------------------------------------------- *//* usbDriverSetup() is similar to usbFunctionSetup(), but it's used for* standard requests instead of class and custom requests.*/static inline usbMsgLen_t usbDriverSetup(usbRequest_t *rq){usbMsgLen_t len = 0;uchar *dataPtr = usbTxBuf + 9; /* there are 2 bytes free space at the end of the buffer */uchar value = rq->wValue.bytes[0];#if USB_CFG_IMPLEMENT_HALTuchar index = rq->wIndex.bytes[0];#endifdataPtr[0] = 0; /* default reply common to USBRQ_GET_STATUS and USBRQ_GET_INTERFACE */SWITCH_START(rq->bRequest)SWITCH_CASE(USBRQ_GET_STATUS) /* 0 */uchar recipient = rq->bmRequestType & USBRQ_RCPT_MASK; /* assign arith ops to variables to enforce byte size */if(USB_CFG_IS_SELF_POWERED && recipient == USBRQ_RCPT_DEVICE)dataPtr[0] = USB_CFG_IS_SELF_POWERED;#if USB_CFG_IMPLEMENT_HALTif(recipient == USBRQ_RCPT_ENDPOINT && index == 0x81) /* request status for endpoint 1 */dataPtr[0] = usbTxLen1 == USBPID_STALL;#endifdataPtr[1] = 0;len = 2;#if USB_CFG_IMPLEMENT_HALTSWITCH_CASE2(USBRQ_CLEAR_FEATURE, USBRQ_SET_FEATURE) /* 1, 3 */if(value == 0 && index == 0x81){ /* feature 0 == HALT for endpoint == 1 */usbTxLen1 = rq->bRequest == USBRQ_CLEAR_FEATURE ? USBPID_NAK : USBPID_STALL;usbResetDataToggling();}#endifSWITCH_CASE(USBRQ_SET_ADDRESS) /* 5 */usbNewDeviceAddr = value;USB_SET_ADDRESS_HOOK();SWITCH_CASE(USBRQ_GET_DESCRIPTOR) /* 6 */len = usbDriverDescriptor(rq);goto skipMsgPtrAssignment;SWITCH_CASE(USBRQ_GET_CONFIGURATION) /* 8 */dataPtr = &usbConfiguration; /* send current configuration value */len = 1;SWITCH_CASE(USBRQ_SET_CONFIGURATION) /* 9 */usbConfiguration = value;usbResetStall();SWITCH_CASE(USBRQ_GET_INTERFACE) /* 10 */len = 1;#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODESWITCH_CASE(USBRQ_SET_INTERFACE) /* 11 */usbResetDataToggling();usbResetStall();#endifSWITCH_DEFAULT /* 7=SET_DESCRIPTOR, 12=SYNC_FRAME *//* Should we add an optional hook here? */SWITCH_ENDusbMsgPtr = (usbMsgPtr_t)dataPtr;skipMsgPtrAssignment:return len;}/* ------------------------------------------------------------------------- *//* usbProcessRx() is called for every message received by the interrupt* routine. It distinguishes between SETUP and DATA packets and processes* them accordingly.*/static inline void usbProcessRx(uchar *data, uchar len){usbRequest_t *rq = (void *)data;/* usbRxToken can be:* 0x2d 00101101 (USBPID_SETUP for setup data)* 0xe1 11100001 (USBPID_OUT: data phase of setup transfer)* 0...0x0f for OUT on endpoint X*/DBG2(0x10 + (usbRxToken & 0xf), data, len + 2); /* SETUP=1d, SETUP-DATA=11, OUTx=1x */USB_RX_USER_HOOK(data, len)#if USB_CFG_IMPLEMENT_FN_WRITEOUTif(usbRxToken < 0x10){ /* OUT to endpoint != 0: endpoint number in usbRxToken */usbFunctionWriteOut(data, len);return;}#endifif(usbRxToken == (uchar)USBPID_SETUP){if(len != 8) /* Setup size must be always 8 bytes. Ignore otherwise. */return;usbMsgLen_t replyLen;usbTxBuf[0] = USBPID_DATA0; /* initialize data toggling */usbTxLen = USBPID_NAK; /* abort pending transmit */usbMsgFlags = 0;uchar type = rq->bmRequestType & USBRQ_TYPE_MASK;if(type != USBRQ_TYPE_STANDARD){ /* standard requests are handled by driver */replyLen = usbFunctionSetup(data);}else{replyLen = usbDriverSetup(rq);}#if USB_CFG_IMPLEMENT_FN_READ || USB_CFG_IMPLEMENT_FN_WRITEif(replyLen == USB_NO_MSG){ /* use user-supplied read/write function *//* do some conditioning on replyLen, but on IN transfers only */if((rq->bmRequestType & USBRQ_DIR_MASK) != USBRQ_DIR_HOST_TO_DEVICE){if(sizeof(replyLen) < sizeof(rq->wLength.word)){ /* help compiler with optimizing */replyLen = rq->wLength.bytes[0];}else{replyLen = rq->wLength.word;}}usbMsgFlags = USB_FLG_USE_USER_RW;}else /* The 'else' prevents that we limit a replyLen of USB_NO_MSG to the maximum transfer len. */#endifif(sizeof(replyLen) < sizeof(rq->wLength.word)){ /* help compiler with optimizing */if(!rq->wLength.bytes[1] && replyLen > rq->wLength.bytes[0]) /* limit length to max */replyLen = rq->wLength.bytes[0];}else{if(replyLen > rq->wLength.word) /* limit length to max */replyLen = rq->wLength.word;}usbMsgLen = replyLen;}else{ /* usbRxToken must be USBPID_OUT, which means data phase of setup (control-out) */#if USB_CFG_IMPLEMENT_FN_WRITEif(usbMsgFlags & USB_FLG_USE_USER_RW){uchar rval = usbFunctionWrite(data, len);if(rval == 0xff){ /* an error occurred */usbTxLen = USBPID_STALL;}else if(rval != 0){ /* This was the final package */usbMsgLen = 0; /* answer with a zero-sized data packet */}}#endif}}/* ------------------------------------------------------------------------- *//* This function is similar to usbFunctionRead(), but it's also called for* data handled automatically by the driver (e.g. descriptor reads).*/static uchar usbDeviceRead(uchar *data, uchar len){if(len > 0){ /* don't bother app with 0 sized reads */#if USB_CFG_IMPLEMENT_FN_READif(usbMsgFlags & USB_FLG_USE_USER_RW){len = usbFunctionRead(data, len);}else#endif{uchar i = len;usbMsgPtr_t r = usbMsgPtr;if(usbMsgFlags & USB_FLG_MSGPTR_IS_ROM){ /* ROM data */do{uchar c = USB_READ_FLASH(r); /* assign to char size variable to enforce byte ops */*data++ = c;r++;}while(--i);}else{ /* RAM data */do{*data++ = *((uchar *)r);r++;}while(--i);}usbMsgPtr = r;}}return len;}/* ------------------------------------------------------------------------- *//* usbBuildTxBlock() is called when we have data to transmit and the* interrupt routine's transmit buffer is empty.*/static inline void usbBuildTxBlock(void){usbMsgLen_t wantLen;uchar len;wantLen = usbMsgLen;if(wantLen > 8)wantLen = 8;usbMsgLen -= wantLen;usbTxBuf[0] ^= USBPID_DATA0 ^ USBPID_DATA1; /* DATA toggling */len = usbDeviceRead(usbTxBuf + 1, wantLen);if(len <= 8){ /* valid data packet */usbCrc16Append(&usbTxBuf[1], len);len += 4; /* length including sync byte */if(len < 12) /* a partial package identifies end of message */usbMsgLen = USB_NO_MSG;}else{len = USBPID_STALL; /* stall the endpoint */usbMsgLen = USB_NO_MSG;}usbTxLen = len;DBG2(0x20, usbTxBuf, len-1);}/* ------------------------------------------------------------------------- */static inline void usbHandleResetHook(uchar notResetState){#ifdef USB_RESET_HOOKstatic uchar wasReset;uchar isReset = !notResetState;if(wasReset != isReset){USB_RESET_HOOK(isReset);wasReset = isReset;}#elsenotResetState = notResetState; // avoid compiler warning#endif}/* ------------------------------------------------------------------------- */USB_PUBLIC void usbPoll(void){schar len;uchar i;len = usbRxLen - 3;if(len >= 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);#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 != USB_NO_MSG){ /* transmit data pending? */usbBuildTxBlock();}}for(i = 20; i > 0; i--){uchar usbLineStatus = USBIN & USBMASK;if(usbLineStatus != 0) /* SE0 has ended */goto isNotReset;}/* RESET condition, called multiple times during reset */usbNewDeviceAddr = 0;usbDeviceAddr = 0;usbResetStall();DBG1(0xff, 0, 0);isNotReset:usbHandleResetHook(i);}/* ------------------------------------------------------------------------- */USB_PUBLIC 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);usbResetDataToggling();#if USB_CFG_HAVE_INTRIN_ENDPOINT && !USB_CFG_SUPPRESS_INTR_CODEusbTxLen1 = USBPID_NAK;#if USB_CFG_HAVE_INTRIN_ENDPOINT3usbTxLen3 = USBPID_NAK;#endif#endif}/* ------------------------------------------------------------------------- */