usbdrv.c

采用atmel公司的mega8芯片设计的USB cdc类

/* 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: Proprietary, free under certain conditions. See Documentation.
 * This Revision: $Id: usbdrv.c 205 2006-06-23 19:01:45Z cs $
 */


#include <avr/io.h>
#include <avr/pgmspace.h>

#include "usbdrv.h"

#define  DBG2(prefix, data, len)
#define  DBG1(prefix, data, len)
/*
General Description:
This module implements the C-part of the USB driver. See usbdrv.h for a
documentation 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: */
/* usbRxBuf MUST be in 1 byte addressable range (because usbInputBuf is only 1 byte) */
__no_init uchar usbRxBuf[2][USB_BUFSIZE] __attribute__ ((section (USB_BUFFER_SECTION))) IAR_SECTION(USB_BUFFER_SECTION);/* raw RX buffer: PID, 8 bytes data, 2 bytes CRC */
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 */
uchar       usbInputBuf;        /* ptr to raw buffer used for receiving */
uchar       usbAppBuf;          /* ptr to raw buffer passed to app for processing */
volatile schar usbRxLen;        /* = 0; number of bytes in usbAppBuf; 0 means free */
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 schar usbTxLen = -1;   /* number of bytes to transmit with next IN token */
uchar       usbTxBuf[USB_BUFSIZE];/* data to transmit with next IN, free if usbTxLen == -1 */
#if USB_CFG_HAVE_INTRIN_ENDPOINT
volatile schar usbTxLen1 = -1;  /* TX count for endpoint 1 */
uchar       usbTxBuf1[USB_BUFSIZE];/* TX data for endpoint 1 */
#if USB_CFG_HAVE_INTRIN_ENDPOINT3
volatile schar usbTxLen3 = -1;  /* TX count for endpoint 1 */
uchar       usbTxBuf3[USB_BUFSIZE];/* TX data for endpoint 1 */
#endif
#endif
uchar       usbAckBuf[1] = {USBPID_ACK};    /* transmit buffer for ack tokens */
uchar       usbNakBuf[1] = {USBPID_NAK};    /* transmit buffer for nak tokens */

/* 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 */
static uchar    usbIsReset;     /* = 0; USB bus is in reset phase */

#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
*/

/* ------------------------------------------------------------------------- */

static PROGMEM char usbDescrDevice[] = {    /* USB device descriptor */
    18,         /* sizeof(usbDescrDevice): length of descriptor in bytes */
    USBDESCR_DEVICE,    /* descriptor type */
    0x01, 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 */
#if USB_CFG_VENDOR_NAME_LEN
    1,          /* manufacturer string index */
#else
    0,          /* manufacturer string index */
#endif
#if USB_CFG_DEVICE_NAME_LEN
    2,          /* product string index */
#else
    0,          /* product string index */
#endif
#if USB_CFG_SERIAL_NUMBER_LENGTH
    3,          /* serial number string index */
#else
    0,          /* serial number string index */
#endif
    1,          /* number of configurations */
};

#if !USB_CFG_EXTERNAL_CONFIG_DESCRIPTOR_LENGH
#define USB_CFG_EXTERNAL_CONFIG_DESCRIPTOR_LENGH    sizeof(usbDescrConfig)
static PROGMEM char usbDescrConfig[] = {    /* USB configuration descriptor */
    9,          /* sizeof(usbDescrConfig): length of descriptor in bytes */
    USBDESCR_CONFIG,    /* descriptor type */
    (18 + 7 * USB_CFG_HAVE_INTRIN_ENDPOINT
#if USB_CFG_HID_REPORT_DESCRIPTOR_LENGTH
     + 9
#endif
        ), 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
    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_HID_REPORT_DESCRIPTOR_LENGTH    /* 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 /* USB_CFG_EXTERNAL_CONFIG_DESCRIPTOR_LENGH */

static PROGMEM char usbDescrString0[] = {   /* language descriptor */
    4,          /* sizeof(usbDescrString0): length of descriptor in bytes */
    3,          /* descriptor type */
    0x09, 0x04, /* language index (0x0409 = US-English) */
};

#if USB_CFG_VENDOR_NAME_LEN
static PROGMEM int  usbDescrString1[] = {
    USB_STRING_DESCRIPTOR_HEADER(USB_CFG_VENDOR_NAME_LEN),
    USB_CFG_VENDOR_NAME
};
#endif
#if USB_CFG_DEVICE_NAME_LEN
static PROGMEM int  usbDescrString2[] = {
    USB_STRING_DESCRIPTOR_HEADER(USB_CFG_DEVICE_NAME_LEN),
    USB_CFG_DEVICE_NAME
};
#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.
 */

/* ------------------------------------------------------------------------- */

#if USB_CFG_HAVE_INTRIN_ENDPOINT
uchar    usbTxPacketCnt1;
#if USB_CFG_IMPLEMENT_HALT
static uchar    usbHalted1;         /* not 0 if endpoint 1 is halted */
#endif

void    usbSetInterrupt(uchar *data, uchar len)
{
uchar       *p, i;

#if USB_CFG_IMPLEMENT_HALT
    if(usbHalted1)
        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
    i = USBPID_DATA1;
    if(usbTxPacketCnt1 & 1)
        i = USBPID_DATA0;
    if(usbTxLen1 < 0){      /* packet buffer was empty */
        usbTxPacketCnt1++;
    }else{
        usbTxLen1 = -1;     /* avoid sending incomplete interrupt data */
    }
    p = usbTxBuf1;
    *p++ = i;
    for(i=len;i--;)
        *p++ = *data++;
    usbCrc16Append(&usbTxBuf1[1], len);
    usbTxLen1 = len + 4;    /* len must be given including sync byte */
#if DEBUG_LEVEL > 1
    DBG2(0x21, usbTxBuf1, len + 3);
#else
    DBG1(0x21, usbTxBuf1 + 1, 2);
#endif
}
#endif

#if USB_CFG_HAVE_INTRIN_ENDPOINT3
uchar    usbTxPacketCnt3;

void    usbSetInterrupt3(const uchar *data, uchar len)
{
uchar       *p, i;

    i = USBPID_DATA1;
    if(usbTxPacketCnt3 & 1)
        i = USBPID_DATA0;
    if(usbTxLen3 < 0){      /* packet buffer was empty */
        usbTxPacketCnt3++;
    }else{
        usbTxLen3 = -1;     /* avoid sending incomplete interrupt data */
    }
    p = usbTxBuf3;
    *p++ = i;
    for(i=len;i--;) {
        *p++ = *data++;
    }
    usbCrc16Append(&usbTxBuf3[1], len);
    usbTxLen3 = len + 4;    /* len must be given including sync byte */
#if DEBUG_LEVEL > 1
    DBG2(0x23, usbTxBuf3, usbTxLen3 - 1);
#else
    DBG1(0x23, usbTxBuf3 + 1, 2);
#endif
}
#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;