- used wrong name in copy -- fixed this

1 files changed, 578 insertions, 0 deletions

diff --git a/usbdrv/usbdrv.c b/usbdrv/usbdrv.c
new file mode 100644
index 0000000..51c76b6
--- /dev/null
+++ b/usbdrv/usbdrv.c
@@ -0,0 +1,578 @@
+/* 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: $Id$
+ */
+
+#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 a
+documentation 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 */
+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_COUNT_SOF
+volatile uchar  usbSofCount;    /* incremented by assembler module every SOF */
+#endif
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+volatile uchar usbTxLen1 = USBPID_NAK;  /* TX count for endpoint 1 */
+uchar       usbTxBuf1[USB_BUFSIZE];     /* TX data for endpoint 1 */
+#   if USB_CFG_HAVE_INTRIN_ENDPOINT3
+volatile uchar usbTxLen3 = USBPID_NAK;  /* TX count for endpoint 3 */
+uchar       usbTxBuf3[USB_BUFSIZE];     /* TX data for endpoint 3 */
+#   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_PRODUCT == 0 && USB_CFG_DEVICE_NAME_LEN
+#undef USB_CFG_DESCR_PROPS_STRING_PRODUCT
+#define USB_CFG_DESCR_PROPS_STRING_PRODUCT   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 */
+    /* 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
+
+#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_POWERED
+    USBATTR_SELFPOWER,      /* attributes */
+#else
+    (char)USBATTR_BUSPOWER, /* attributes */
+#endif
+    USB_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 */
+    (char)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)
+#endif
+
+typedef 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.
+ */
+
+/* ------------------------------------------------------------------------- */
+
+static inline void  usbResetDataToggling(void)
+{
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+    USB_SET_DATATOKEN1(USB_INITIAL_DATATOKEN);  /* reset data toggling for interrupt endpoint */
+#   if USB_CFG_HAVE_INTRIN_ENDPOINT3
+    USB_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_ENDPOINT
+        usbTxLen1 = USBPID_NAK;
+#if USB_CFG_HAVE_INTRIN_ENDPOINT3
+        usbTxLen3 = USBPID_NAK;
+#endif
+#endif
+}
+
+/* ------------------------------------------------------------------------- */
+
+#if USB_CFG_HAVE_INTRIN_ENDPOINT
+USB_PUBLIC void usbSetInterrupt(uchar *data, uchar len)
+{
+uchar       *p, i;
+
+#if USB_CFG_IMPLEMENT_HALT
+    if(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;
+#endif
+    if(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_ENDPOINT3
+USB_PUBLIC void 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);
+}
+#endif
+
+
+static uchar usbRead(uchar *data, uchar len)
+{
+#if USB_CFG_IMPLEMENT_FN_READ
+    if(usbMsgFlags & USB_FLG_USE_DEFAULT_RW){
+#endif
+        uchar 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 */
+#ifdef USB_RX_USER_HOOK
+    USB_RX_USER_HOOK(data, len)
+#endif
+#if USB_CFG_IMPLEMENT_FN_WRITEOUT
+    if(usbRxToken < 0x10){  /* endpoint number in usbRxToken */
+        usbFunctionWriteOut(data, len);
+        return; /* no reply expected, hence no usbMsgPtr, usbMsgFlags, usbMsgLen set */
+    }
+#endif
+    if(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_POWERED
+                    if(recipient == USBRQ_RCPT_DEVICE)
+                        replyData[0] =  USB_CFG_IS_SELF_POWERED;
+#endif
+#if USB_CFG_HAVE_INTRIN_ENDPOINT && USB_CFG_IMPLEMENT_HALT
+                    if(recipient == USBRQ_RCPT_ENDPOINT && rq->wIndex.bytes[0] == 0x81)   /* request status for endpoint 1 */
+                        replyData[0] = usbTxLen1 == USBPID_STALL;
+#endif
+                    replyData[1] = 0;
+                    SET_REPLY_LEN(2);
+                }else if(rq->bRequest == USBRQ_SET_ADDRESS){    /* 5 */
+                    usbNewDeviceAddr = rq->wValue.bytes[0];
+#ifdef USB_SET_ADDRESS_HOOK
+                    USB_SET_ADDRESS_HOOK();
+#endif
+                }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_DYNAMIC
+                        if(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_PRODUCT, 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 */
+#if USB_CFG_DESCR_PROPS_HID_REPORT  /* only support HID descriptors if enabled */
+                    }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)
+#endif  /* USB_CFG_DESCR_PROPS_HID_REPORT */
+                    }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];
+                    usbResetStall();
+                }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 */
+                    usbResetDataToggling();
+                    usbResetStall();
+#   if USB_CFG_IMPLEMENT_HALT
+                }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;
+                        usbResetDataToggling();
+                    }
+#   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_WRITE
+            if(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. */
+#endif
+            if(!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_WRITE
+        if(!(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;
+}
+
+static inline void usbHandleResetHook(uchar notResetState)
+{
+#ifdef USB_RESET_HOOK
+static uchar    wasReset;
+uchar           isReset = !notResetState;
+
+    if(wasReset != isReset){
+        USB_RESET_HOOK(isReset);
+        wasReset = isReset;
+    }
+#endif
+}
+
+/* ------------------------------------------------------------------------- */
+
+USB_PUBLIC void usbPoll(void)
+{
+schar   len;
+uchar   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_FLOWCONTROL
+        if(usbRxLen > 0)    /* only mark as available if not inactivated */
+            usbRxLen = 0;
+#else
+        usbRxLen = 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;
+        usbResetStall();
+        DBG1(0xff, 0, 0);
+    }
+    usbHandleResetHook(i);
+}
+
+/* ------------------------------------------------------------------------- */
+
+USB_PUBLIC void usbInit(void)
+{
+#if USB_INTR_CFG_SET != 0
+    USB_INTR_CFG |= USB_INTR_CFG_SET;
+#endif
+#if USB_INTR_CFG_CLR != 0
+    USB_INTR_CFG &= ~(USB_INTR_CFG_CLR);
+#endif
+    USB_INTR_ENABLE |= (1 << USB_INTR_ENABLE_BIT);
+    usbResetDataToggling();
+}
+
+/* ------------------------------------------------------------------------- */