git.zerfleddert.de Git - proxmark3-svn/blob - common/usb_cdc.c

   1 /*
   2  * at91sam7s USB CDC device implementation
   3  *
   4  * Copyright (c) 2012, Roel Verdult
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  * 3. Neither the name of the copyright holders nor the
  15  * names of its contributors may be used to endorse or promote products
  16  * derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
  19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
  22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  27  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * based on the "Basic USB Example" from ATMEL (doc6123.pdf)
  30  *
  31  * @file usb_cdc.c
  32  * @brief
  33  */
  34
  35 #include "usb_cdc.h"
  36 #include "config_gpio.h"
  37
  38 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
  39 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
  40 #define AT91C_EP_IN_SIZE  0x40
  41 #define AT91C_EP_OUT         1
  42 #define AT91C_EP_OUT_SIZE 0x40
  43 #define AT91C_EP_IN          2
  44
  45 const char devDescriptor[] = {
  46         /* Device descriptor */
  47         0x12,      // bLength
  48         0x01,      // bDescriptorType
  49         0x10,0x01, // Complies with USB Spec. Release (0110h = release 1.10)
  50         0x02,      // bDeviceClass:    CDC class code
  51         0x00,      // bDeviceSubclass: CDC class sub code
  52         0x00,      // bDeviceProtocol: CDC Device protocol
  53         0x08,      // bMaxPacketSize0
  54         0x2d,0x2d, // Vendor ID (--)
  55         0x4d,0x50, // Product ID (PM), transmitted in reverse
  56         0x01,0x00, // Device release number (0001)
  57         0x01,      // iManufacturer    // 0x01
  58         0x00,      // iProduct
  59         0x00,      // SerialNumber
  60         0x01       // bNumConfigs
  61 };
  62
  63 const char cfgDescriptor[] = {
  64         /* ============== CONFIGURATION 1 =========== */
  65         /* Configuration 1 descriptor */
  66         0x09,   // CbLength
  67         0x02,   // CbDescriptorType
  68         0x43,   // CwTotalLength 2 EP + Control
  69         0x00,
  70         0x02,   // CbNumInterfaces
  71         0x01,   // CbConfigurationValue
  72         0x00,   // CiConfiguration
  73         0xC0,   // CbmAttributes 0xA0
  74         0x00,   // CMaxPower
  75
  76         /* Communication Class Interface Descriptor Requirement */
  77         0x09, // bLength
  78         0x04, // bDescriptorType
  79         0x00, // bInterfaceNumber
  80         0x00, // bAlternateSetting
  81         0x01, // bNumEndpoints
  82         0x02, // bInterfaceClass
  83         0x02, // bInterfaceSubclass
  84         0x00, // bInterfaceProtocol
  85         0x00, // iInterface
  86
  87         /* Header Functional Descriptor */
  88         0x05, // bFunction Length
  89         0x24, // bDescriptor type: CS_INTERFACE
  90         0x00, // bDescriptor subtype: Header Func Desc
  91         0x10, // bcdCDC:1.1
  92         0x01,
  93
  94         /* ACM Functional Descriptor */
  95         0x04, // bFunctionLength
  96         0x24, // bDescriptor Type: CS_INTERFACE
  97         0x02, // bDescriptor Subtype: ACM Func Desc
  98         0x00, // bmCapabilities
  99
 100         /* Union Functional Descriptor */
 101         0x05, // bFunctionLength
 102         0x24, // bDescriptorType: CS_INTERFACE
 103         0x06, // bDescriptor Subtype: Union Func Desc
 104         0x00, // bMasterInterface: Communication Class Interface
 105         0x01, // bSlaveInterface0: Data Class Interface
 106
 107         /* Call Management Functional Descriptor */
 108         0x05, // bFunctionLength
 109         0x24, // bDescriptor Type: CS_INTERFACE
 110         0x01, // bDescriptor Subtype: Call Management Func Desc
 111         0x00, // bmCapabilities: D1 + D0
 112         0x01, // bDataInterface: Data Class Interface 1
 113
 114         /* Endpoint 1 descriptor */
 115         0x07,   // bLength
 116         0x05,   // bDescriptorType
 117         0x83,   // bEndpointAddress, Endpoint 03 - IN
 118         0x03,   // bmAttributes      INT
 119         0x08,   // wMaxPacketSize
 120         0x00,
 121         0xFF,   // bInterval
 122
 123         /* Data Class Interface Descriptor Requirement */
 124         0x09, // bLength
 125         0x04, // bDescriptorType
 126         0x01, // bInterfaceNumber
 127         0x00, // bAlternateSetting
 128         0x02, // bNumEndpoints
 129         0x0A, // bInterfaceClass
 130         0x00, // bInterfaceSubclass
 131         0x00, // bInterfaceProtocol
 132         0x00, // iInterface
 133
 134         /* First alternate setting */
 135         /* Endpoint 1 descriptor */
 136         0x07,   // bLength
 137         0x05,   // bDescriptorType
 138         0x01,   // bEndpointAddress, Endpoint 01 - OUT
 139         0x02,   // bmAttributes      BULK
 140         AT91C_EP_OUT_SIZE,   // wMaxPacketSize
 141         0x00,
 142         0x00,   // bInterval
 143
 144         /* Endpoint 2 descriptor */
 145         0x07,   // bLength
 146         0x05,   // bDescriptorType
 147         0x82,   // bEndpointAddress, Endpoint 02 - IN
 148         0x02,   // bmAttributes      BULK
 149         AT91C_EP_IN_SIZE,   // wMaxPacketSize
 150         0x00,
 151         0x00    // bInterval
 152 };
 153
 154 const char strDescriptor[] = {
 155   26,                           // Length
 156   0x03,                 // Type is string
 157   'p', 0x00,
 158   'r', 0x00,
 159   'o', 0x00,
 160   'x', 0x00,
 161   'm', 0x00,
 162   'a', 0x00,
 163   'r', 0x00,
 164   'k', 0x00,
 165   '.', 0x00,
 166   'o', 0x00,
 167   'r', 0x00,
 168   'g', 0x00,
 169 };
 170
 171
 172 /* USB standard request code */
 173 #define STD_GET_STATUS_ZERO           0x0080
 174 #define STD_GET_STATUS_INTERFACE      0x0081
 175 #define STD_GET_STATUS_ENDPOINT       0x0082
 176
 177 #define STD_CLEAR_FEATURE_ZERO        0x0100
 178 #define STD_CLEAR_FEATURE_INTERFACE   0x0101
 179 #define STD_CLEAR_FEATURE_ENDPOINT    0x0102
 180
 181 #define STD_SET_FEATURE_ZERO          0x0300
 182 #define STD_SET_FEATURE_INTERFACE     0x0301
 183 #define STD_SET_FEATURE_ENDPOINT      0x0302
 184
 185 #define STD_SET_ADDRESS               0x0500
 186 #define STD_GET_DESCRIPTOR            0x0680
 187 #define STD_SET_DESCRIPTOR            0x0700
 188 #define STD_GET_CONFIGURATION         0x0880
 189 #define STD_SET_CONFIGURATION         0x0900
 190 #define STD_GET_INTERFACE             0x0A81
 191 #define STD_SET_INTERFACE             0x0B01
 192 #define STD_SYNCH_FRAME               0x0C82
 193
 194 /* CDC Class Specific Request Code */
 195 #define GET_LINE_CODING               0x21A1
 196 #define SET_LINE_CODING               0x2021
 197 #define SET_CONTROL_LINE_STATE        0x2221
 198
 199 typedef struct {
 200         unsigned int dwDTERRate;
 201         char bCharFormat;
 202         char bParityType;
 203         char bDataBits;
 204 } AT91S_CDC_LINE_CODING, *AT91PS_CDC_LINE_CODING;
 205
 206 AT91S_CDC_LINE_CODING line = {
 207         115200, // baudrate
 208         0,      // 1 Stop Bit
 209         0,      // None Parity
 210         8};     // 8 Data bits
 211
 212 void AT91F_CDC_Enumerate();
 213
 214 AT91PS_UDP pUdp = AT91C_BASE_UDP;
 215 byte_t btConfiguration = 0;
 216 byte_t btConnection    = 0;
 217 byte_t btReceiveBank   = AT91C_UDP_RX_DATA_BK0;
 218
 219 //*----------------------------------------------------------------------------
 220 //* \fn    usb_disable
 221 //* \brief This function deactivates the USB device
 222 //*----------------------------------------------------------------------------
 223 void usb_disable() {
 224   // Disconnect the USB device
 225   AT91C_BASE_PIOA->PIO_ODR = GPIO_USB_PU;
 226
 227   // Clear all lingering interrupts
 228   if(pUdp->UDP_ISR & AT91C_UDP_ENDBUSRES) {
 229     pUdp->UDP_ICR = AT91C_UDP_ENDBUSRES;
 230   }
 231 }
 232
 233 //*----------------------------------------------------------------------------
 234 //* \fn    usb_enable
 235 //* \brief This function Activates the USB device
 236 //*----------------------------------------------------------------------------
 237 void usb_enable() {
 238   // Set the PLL USB Divider
 239   AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1 ;
 240
 241   // Specific Chip USB Initialisation
 242   // Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock
 243   AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
 244   AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
 245
 246   // Enable UDP PullUp (USB_DP_PUP) : enable & Clear of the corresponding PIO
 247   // Set in PIO mode and Configure in Output
 248   AT91C_BASE_PIOA->PIO_PER = GPIO_USB_PU; // Set in PIO mode
 249         AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU; // Configure as Output
 250
 251   // Clear for set the Pullup resistor
 252         AT91C_BASE_PIOA->PIO_CODR = GPIO_USB_PU;
 253
 254   // Disconnect and reconnect USB controller for 100ms
 255   usb_disable();
 256
 257   // Wait for a short while
 258   for (volatile size_t i=0; i<0x100000; i++);
 259
 260   // Reconnect USB reconnect
 261   AT91C_BASE_PIOA->PIO_SODR = GPIO_USB_PU;
 262   AT91C_BASE_PIOA->PIO_OER = GPIO_USB_PU;
 263 }
 264
 265 //*----------------------------------------------------------------------------
 266 //* \fn    usb_check
 267 //* \brief Test if the device is configured and handle enumeration
 268 //*----------------------------------------------------------------------------
 269 bool usb_check() {
 270         AT91_REG isr = pUdp->UDP_ISR;
 271
 272         if (isr & AT91C_UDP_ENDBUSRES) {
 273                 pUdp->UDP_ICR = AT91C_UDP_ENDBUSRES;
 274                 // reset all endpoints
 275                 pUdp->UDP_RSTEP  = (unsigned int)-1;
 276                 pUdp->UDP_RSTEP  = 0;
 277                 // Enable the function
 278                 pUdp->UDP_FADDR = AT91C_UDP_FEN;
 279                 // Configure endpoint 0
 280                 pUdp->UDP_CSR[0] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_CTRL);
 281         }
 282         else if (isr & AT91C_UDP_EPINT0) {
 283                 pUdp->UDP_ICR = AT91C_UDP_EPINT0;
 284                 AT91F_CDC_Enumerate();
 285         }
 286         return (btConfiguration) ? true : false;
 287 }
 288
 289
 290 bool usb_poll()
 291 {
 292   if (!usb_check()) return false;
 293   return (pUdp->UDP_CSR[AT91C_EP_OUT] & btReceiveBank);
 294 }
 295
 296 //*----------------------------------------------------------------------------
 297 //* \fn    usb_read
 298 //* \brief Read available data from Endpoint OUT
 299 //*----------------------------------------------------------------------------
 300 uint32_t usb_read(byte_t* data, size_t len) {
 301   byte_t bank = btReceiveBank;
 302         uint32_t packetSize, nbBytesRcv = 0;
 303   uint32_t time_out = 0;
 304
 305         while (len)  {
 306                 if (!usb_check()) break;
 307
 308                 if ( pUdp->UDP_CSR[AT91C_EP_OUT] & bank ) {
 309                         packetSize = MIN(pUdp->UDP_CSR[AT91C_EP_OUT] >> 16, len);
 310       len -= packetSize;
 311                         while(packetSize--)
 312                                 data[nbBytesRcv++] = pUdp->UDP_FDR[AT91C_EP_OUT];
 313                         pUdp->UDP_CSR[AT91C_EP_OUT] &= ~(bank);
 314                         if (bank == AT91C_UDP_RX_DATA_BK0) {
 315                                 bank = AT91C_UDP_RX_DATA_BK1;
 316       } else {
 317                                 bank = AT91C_UDP_RX_DATA_BK0;
 318       }
 319                 }
 320     if (time_out++ == 0x1fff) break;
 321         }
 322
 323         btReceiveBank = bank;
 324         return nbBytesRcv;
 325 }
 326
 327 //*----------------------------------------------------------------------------
 328 //* \fn    usb_write
 329 //* \brief Send through endpoint 2
 330 //*----------------------------------------------------------------------------
 331 uint32_t usb_write(const byte_t* data, const size_t len) {
 332   size_t length = len;
 333         uint32_t cpt = 0;
 334
 335   if (!length) return 0;
 336   if (!usb_check()) return 0;
 337
 338         // Send the first packet
 339         cpt = MIN(length, AT91C_EP_IN_SIZE-1);
 340         length -= cpt;
 341         while (cpt--) pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
 342         pUdp->UDP_CSR[AT91C_EP_IN] |= AT91C_UDP_TXPKTRDY;
 343
 344         while (length) {
 345                 // Fill the second bank
 346                 cpt = MIN(length, AT91C_EP_IN_SIZE-1);
 347                 length -= cpt;
 348                 while (cpt--) pUdp->UDP_FDR[AT91C_EP_IN] = *data++;
 349                 // Wait for the the first bank to be sent
 350                 while (!(pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP)) {
 351                         if (!usb_check()) return length;
 352     }
 353                 pUdp->UDP_CSR[AT91C_EP_IN] &= ~(AT91C_UDP_TXCOMP);
 354                 while (pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP);
 355                 pUdp->UDP_CSR[AT91C_EP_IN] |= AT91C_UDP_TXPKTRDY;
 356         }
 357
 358         // Wait for the end of transfer
 359         while (!(pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP)) {
 360                 if (!usb_check()) return length;
 361   }
 362
 363         pUdp->UDP_CSR[AT91C_EP_IN] &= ~(AT91C_UDP_TXCOMP);
 364         while (pUdp->UDP_CSR[AT91C_EP_IN] & AT91C_UDP_TXCOMP);
 365
 366         return length;
 367 }
 368
 369 //*----------------------------------------------------------------------------
 370 //* \fn    AT91F_USB_SendData
 371 //* \brief Send Data through the control endpoint
 372 //*----------------------------------------------------------------------------
 373 unsigned int csrTab[100] = {0x00};
 374 unsigned char csrIdx = 0;
 375
 376 static void AT91F_USB_SendData(AT91PS_UDP pUdp, const char *pData, uint32_t length) {
 377         uint32_t cpt = 0;
 378         AT91_REG csr;
 379
 380         do {
 381                 cpt = MIN(length, 8);
 382                 length -= cpt;
 383
 384                 while (cpt--)
 385                         pUdp->UDP_FDR[0] = *pData++;
 386
 387                 if (pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP) {
 388                         pUdp->UDP_CSR[0] &= ~(AT91C_UDP_TXCOMP);
 389                         while (pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP);
 390                 }
 391
 392                 pUdp->UDP_CSR[0] |= AT91C_UDP_TXPKTRDY;
 393                 do {
 394                         csr = pUdp->UDP_CSR[0];
 395
 396                         // Data IN stage has been stopped by a status OUT
 397                         if (csr & AT91C_UDP_RX_DATA_BK0) {
 398                                 pUdp->UDP_CSR[0] &= ~(AT91C_UDP_RX_DATA_BK0);
 399                                 return;
 400                         }
 401                 } while ( !(csr & AT91C_UDP_TXCOMP) );
 402
 403         } while (length);
 404
 405         if (pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP) {
 406                 pUdp->UDP_CSR[0] &= ~(AT91C_UDP_TXCOMP);
 407                 while (pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP);
 408         }
 409 }
 410
 411 //*----------------------------------------------------------------------------
 412 //* \fn    AT91F_USB_SendZlp
 413 //* \brief Send zero length packet through the control endpoint
 414 //*----------------------------------------------------------------------------
 415 void AT91F_USB_SendZlp(AT91PS_UDP pUdp) {
 416         pUdp->UDP_CSR[0] |= AT91C_UDP_TXPKTRDY;
 417         while ( !(pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP) );
 418         pUdp->UDP_CSR[0] &= ~(AT91C_UDP_TXCOMP);
 419         while (pUdp->UDP_CSR[0] & AT91C_UDP_TXCOMP);
 420 }
 421
 422 //*----------------------------------------------------------------------------
 423 //* \fn    AT91F_USB_SendStall
 424 //* \brief Stall the control endpoint
 425 //*----------------------------------------------------------------------------
 426 void AT91F_USB_SendStall(AT91PS_UDP pUdp) {
 427         pUdp->UDP_CSR[0] |= AT91C_UDP_FORCESTALL;
 428         while ( !(pUdp->UDP_CSR[0] & AT91C_UDP_ISOERROR) );
 429         pUdp->UDP_CSR[0] &= ~(AT91C_UDP_FORCESTALL | AT91C_UDP_ISOERROR);
 430         while (pUdp->UDP_CSR[0] & (AT91C_UDP_FORCESTALL | AT91C_UDP_ISOERROR));
 431 }
 432
 433 //*----------------------------------------------------------------------------
 434 //* \fn    AT91F_CDC_Enumerate
 435 //* \brief This function is a callback invoked when a SETUP packet is received
 436 //*----------------------------------------------------------------------------
 437 void AT91F_CDC_Enumerate() {
 438         byte_t bmRequestType, bRequest;
 439         uint16_t wValue, wIndex, wLength, wStatus;
 440
 441         if ( !(pUdp->UDP_CSR[0] & AT91C_UDP_RXSETUP) )
 442                 return;
 443
 444         bmRequestType = pUdp->UDP_FDR[0];
 445         bRequest      = pUdp->UDP_FDR[0];
 446         wValue        = (pUdp->UDP_FDR[0] & 0xFF);
 447         wValue       |= (pUdp->UDP_FDR[0] << 8);
 448         wIndex        = (pUdp->UDP_FDR[0] & 0xFF);
 449         wIndex       |= (pUdp->UDP_FDR[0] << 8);
 450         wLength       = (pUdp->UDP_FDR[0] & 0xFF);
 451         wLength      |= (pUdp->UDP_FDR[0] << 8);
 452
 453         if (bmRequestType & 0x80) {
 454                 pUdp->UDP_CSR[0] |= AT91C_UDP_DIR;
 455                 while ( !(pUdp->UDP_CSR[0] & AT91C_UDP_DIR) );
 456         }
 457         pUdp->UDP_CSR[0] &= ~AT91C_UDP_RXSETUP;
 458         while ( (pUdp->UDP_CSR[0]  & AT91C_UDP_RXSETUP)  );
 459
 460         // Handle supported standard device request Cf Table 9-3 in USB specification Rev 1.1
 461         switch ((bRequest << 8) | bmRequestType) {
 462         case STD_GET_DESCRIPTOR:
 463                 if (wValue == 0x100)       // Return Device Descriptor
 464                         AT91F_USB_SendData(pUdp, devDescriptor, MIN(sizeof(devDescriptor), wLength));
 465                 else if (wValue == 0x200)  // Return Configuration Descriptor
 466                         AT91F_USB_SendData(pUdp, cfgDescriptor, MIN(sizeof(cfgDescriptor), wLength));
 467                 else if ((wValue & 0x300) == 0x300)  // Return String Descriptor
 468                         AT91F_USB_SendData(pUdp, strDescriptor, MIN(sizeof(strDescriptor), wLength));
 469                 else
 470                         AT91F_USB_SendStall(pUdp);
 471                 break;
 472         case STD_SET_ADDRESS:
 473                 AT91F_USB_SendZlp(pUdp);
 474                 pUdp->UDP_FADDR = (AT91C_UDP_FEN | wValue);
 475                 pUdp->UDP_GLBSTATE  = (wValue) ? AT91C_UDP_FADDEN : 0;
 476                 break;
 477         case STD_SET_CONFIGURATION:
 478                 btConfiguration = wValue;
 479                 AT91F_USB_SendZlp(pUdp);
 480                 pUdp->UDP_GLBSTATE  = (wValue) ? AT91C_UDP_CONFG : AT91C_UDP_FADDEN;
 481                 pUdp->UDP_CSR[1] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT) : 0;
 482                 pUdp->UDP_CSR[2] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN)  : 0;
 483                 pUdp->UDP_CSR[3] = (wValue) ? (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN)   : 0;
 484                 break;
 485         case STD_GET_CONFIGURATION:
 486                 AT91F_USB_SendData(pUdp, (char *) &(btConfiguration), sizeof(btConfiguration));
 487                 break;
 488         case STD_GET_STATUS_ZERO:
 489                 wStatus = 0;
 490                 AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 491                 break;
 492         case STD_GET_STATUS_INTERFACE:
 493                 wStatus = 0;
 494                 AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 495                 break;
 496         case STD_GET_STATUS_ENDPOINT:
 497                 wStatus = 0;
 498                 wIndex &= 0x0F;
 499                 if ((pUdp->UDP_GLBSTATE & AT91C_UDP_CONFG) && (wIndex <= 3)) {
 500                         wStatus = (pUdp->UDP_CSR[wIndex] & AT91C_UDP_EPEDS) ? 0 : 1;
 501                         AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 502                 }
 503                 else if ((pUdp->UDP_GLBSTATE & AT91C_UDP_FADDEN) && (wIndex == 0)) {
 504                         wStatus = (pUdp->UDP_CSR[wIndex] & AT91C_UDP_EPEDS) ? 0 : 1;
 505                         AT91F_USB_SendData(pUdp, (char *) &wStatus, sizeof(wStatus));
 506                 }
 507                 else
 508                         AT91F_USB_SendStall(pUdp);
 509                 break;
 510         case STD_SET_FEATURE_ZERO:
 511                 AT91F_USB_SendStall(pUdp);
 512             break;
 513         case STD_SET_FEATURE_INTERFACE:
 514                 AT91F_USB_SendZlp(pUdp);
 515                 break;
 516         case STD_SET_FEATURE_ENDPOINT:
 517                 wIndex &= 0x0F;
 518                 if ((wValue == 0) && wIndex && (wIndex <= 3)) {
 519                         pUdp->UDP_CSR[wIndex] = 0;
 520                         AT91F_USB_SendZlp(pUdp);
 521                 }
 522                 else
 523                         AT91F_USB_SendStall(pUdp);
 524                 break;
 525         case STD_CLEAR_FEATURE_ZERO:
 526                 AT91F_USB_SendStall(pUdp);
 527             break;
 528         case STD_CLEAR_FEATURE_INTERFACE:
 529                 AT91F_USB_SendZlp(pUdp);
 530                 break;
 531         case STD_CLEAR_FEATURE_ENDPOINT:
 532                 wIndex &= 0x0F;
 533                 if ((wValue == 0) && wIndex && (wIndex <= 3)) {
 534                         if (wIndex == 1)
 535                                 pUdp->UDP_CSR[1] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_OUT);
 536                         else if (wIndex == 2)
 537                                 pUdp->UDP_CSR[2] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_BULK_IN);
 538                         else if (wIndex == 3)
 539                                 pUdp->UDP_CSR[3] = (AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_ISO_IN);
 540                         AT91F_USB_SendZlp(pUdp);
 541                 }
 542                 else
 543                         AT91F_USB_SendStall(pUdp);
 544                 break;
 545
 546         // handle CDC class requests
 547         case SET_LINE_CODING:
 548                 while ( !(pUdp->UDP_CSR[0] & AT91C_UDP_RX_DATA_BK0) );
 549                 pUdp->UDP_CSR[0] &= ~(AT91C_UDP_RX_DATA_BK0);
 550                 AT91F_USB_SendZlp(pUdp);
 551                 break;
 552         case GET_LINE_CODING:
 553                 AT91F_USB_SendData(pUdp, (char *) &line, MIN(sizeof(line), wLength));
 554                 break;
 555         case SET_CONTROL_LINE_STATE:
 556                 btConnection = wValue;
 557                 AT91F_USB_SendZlp(pUdp);
 558                 break;
 559         default:
 560                 AT91F_USB_SendStall(pUdp);
 561             break;
 562         }
 563 }