Demos/Host/LowLevel/RNDISEthernetHost/ConfigDescriptor.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  USB Device Configuration Descriptor processing routines, to determine the correct pipe configurations
  34  *  needed to communication with an attached USB device. Descriptors are special  computer-readable structures
  35  *  which the host requests upon device enumeration, to determine the device's capabilities and functions.
  36  */
  37
  38 #include "ConfigDescriptor.h"
  39
  40 /** Reads and processes an attached device's descriptors, to determine compatibility and pipe configurations. This
  41  *  routine will read in the entire configuration descriptor, and configure the hosts pipes to correctly communicate
  42  *  with compatible devices.
  43  *
  44  *  This routine searches for a RNDIS interface descriptor containing bulk data IN and OUT endpoints, and an interrupt event endpoint.
  45  *
  46  *  \return An error code from the \ref RNDISHost_GetConfigDescriptorDataCodes_t enum.
  47  */
  48 uint8_t ProcessConfigurationDescriptor(void)
  49 {
  50         uint8_t  ConfigDescriptorData[512];
  51         void*    CurrConfigLocation = ConfigDescriptorData;
  52         uint16_t CurrConfigBytesRem;
  53         uint8_t  FoundEndpoints = 0;
  54
  55         /* Retrieve the entire configuration descriptor into the allocated buffer */
  56         switch (USB_Host_GetDeviceConfigDescriptor(1, &CurrConfigBytesRem, ConfigDescriptorData, sizeof(ConfigDescriptorData)))
  57         {
  58                 case HOST_GETCONFIG_Successful:
  59                         break;
  60                 case HOST_GETCONFIG_InvalidData:
  61                         return InvalidConfigDataReturned;
  62                 case HOST_GETCONFIG_BuffOverflow:
  63                         return DescriptorTooLarge;
  64                 default:
  65                         return ControlError;
  66         }
  67
  68         /* Get the CDC control interface from the configuration descriptor */
  69         if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
  70                                       DComp_NextCDCControlInterface) != DESCRIPTOR_SEARCH_COMP_Found)
  71         {
  72                 /* Descriptor not found, error out */
  73                 return NoRNDISInterfaceFound;
  74         }
  75
  76         /* Get the IN and OUT data and IN notification endpoints for the RNDIS interface */
  77         while (FoundEndpoints != ((1 << RNDIS_NOTIFICATIONPIPE) | (1 << RNDIS_DATAPIPE_IN) | (1 << RNDIS_DATAPIPE_OUT)))
  78         {
  79                 /* Fetch the next bulk or interrupt endpoint from the current RNDIS interface */
  80                 if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
  81                                               DComp_NextCDCDataInterfaceEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
  82                 {
  83                         /* Check to see if the control interface's notification pipe has been found, if so search for the data interface */
  84                         if (FoundEndpoints & (1 << RNDIS_NOTIFICATIONPIPE))
  85                         {
  86                                 /* Get the next CDC data interface from the configuration descriptor (RNDIS class has two CDC interfaces) */
  87                                 if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
  88                                                               DComp_NextCDCDataInterface) != DESCRIPTOR_SEARCH_COMP_Found)
  89                                 {
  90                                         /* Descriptor not found, error out */
  91                                         return NoRNDISInterfaceFound;
  92                                 }
  93                         }
  94                         else
  95                         {
  96                                 /* Clear the found endpoints mask, since any already processed endpoints aren't in the CDC interface we need */
  97                                 FoundEndpoints = 0;
  98
  99                                 /* Disable any already configured pipes from the invalid RNDIS interfaces */
 100                                 Pipe_SelectPipe(RNDIS_NOTIFICATIONPIPE);
 101                                 Pipe_DisablePipe();
 102                                 Pipe_SelectPipe(RNDIS_DATAPIPE_IN);
 103                                 Pipe_DisablePipe();
 104                                 Pipe_SelectPipe(RNDIS_DATAPIPE_OUT);
 105                                 Pipe_DisablePipe();
 106
 107                                 /* Get the next CDC control interface from the configuration descriptor (CDC class has two CDC interfaces) */
 108                                 if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
 109                                                               DComp_NextCDCControlInterface) != DESCRIPTOR_SEARCH_COMP_Found)
 110                                 {
 111                                         /* Descriptor not found, error out */
 112                                         return NoRNDISInterfaceFound;
 113                                 }
 114                         }
 115
 116                         /* Fetch the next bulk or interrupt endpoint from the current CDC interface */
 117                         if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
 118                                                       DComp_NextCDCDataInterfaceEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
 119                         {
 120                                 /* Descriptor not found, error out */
 121                                 return NoEndpointFound;
 122                         }
 123                 }
 124
 125                 USB_Descriptor_Endpoint_t* EndpointData = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Endpoint_t);
 126
 127                 /* Check if the found endpoint is a interrupt or bulk type descriptor */
 128                 if ((EndpointData->Attributes & EP_TYPE_MASK) == EP_TYPE_INTERRUPT)
 129                 {
 130                         /* If the endpoint is a IN type interrupt endpoint */
 131                         if (EndpointData->EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN)
 132                         {
 133                                 /* Configure the notification pipe */
 134                                 Pipe_ConfigurePipe(RNDIS_NOTIFICATIONPIPE, EP_TYPE_INTERRUPT, PIPE_TOKEN_IN,
 135                                                                    EndpointData->EndpointAddress, EndpointData->EndpointSize, PIPE_BANK_SINGLE);
 136
 137                                 Pipe_SetInterruptPeriod(EndpointData->PollingIntervalMS);
 138
 139                                 /* Set the flag indicating that the notification pipe has been found */
 140                                 FoundEndpoints |= (1 << RNDIS_NOTIFICATIONPIPE);
 141                         }
 142                 }
 143                 else
 144                 {
 145                         /* Check if the endpoint is a bulk IN or bulk OUT endpoint */
 146                         if (EndpointData->EndpointAddress & ENDPOINT_DESCRIPTOR_DIR_IN)
 147                         {
 148                                 /* Kill the configured OUT pipe if the data endpoints are bidirectional */
 149                                 if (Pipe_IsEndpointBound(EndpointData->EndpointAddress))
 150                                   Pipe_DisablePipe();
 151
 152                                 /* Configure the data IN pipe */
 153                                 Pipe_ConfigurePipe(RNDIS_DATAPIPE_IN, EP_TYPE_BULK, PIPE_TOKEN_IN,
 154                                                                    EndpointData->EndpointAddress, EndpointData->EndpointSize, PIPE_BANK_SINGLE);
 155
 156                                 /* Set the flag indicating that the data IN pipe has been found */
 157                                 FoundEndpoints |= (1 << RNDIS_DATAPIPE_IN);
 158                         }
 159                         else
 160                         {
 161                                 /* Only configure the OUT data pipe if the data endpoints haev not shown to be bidirectional */
 162                                 if (!(Pipe_IsEndpointBound(EndpointData->EndpointAddress)))
 163                                 {
 164                                         /* Configure the data OUT pipe */
 165                                         Pipe_ConfigurePipe(RNDIS_DATAPIPE_OUT, EP_TYPE_BULK, PIPE_TOKEN_OUT,
 166                                                                            EndpointData->EndpointAddress, EndpointData->EndpointSize, PIPE_BANK_SINGLE);
 167                                 }
 168
 169                                 /* Set the flag indicating that the data OUT pipe has been found */
 170                                 FoundEndpoints |= (1 << RNDIS_DATAPIPE_OUT);
 171                         }
 172                 }
 173         }
 174
 175         /* Valid data found, return success */
 176         return SuccessfulConfigRead;
 177 }
 178
 179 /** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
 180  *  configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
 181  *  descriptor processing if an incompatible descriptor configuration is found.
 182  *
 183  *  This comparator searches for the next Interface descriptor of the correct CDC control Class, Subclass and Protocol values.
 184  *
 185  *  \return A value from the DSEARCH_Return_ErrorCodes_t enum
 186  */
 187 uint8_t DComp_NextCDCControlInterface(void* CurrentDescriptor)
 188 {
 189         if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
 190         {
 191                 /* Check the CDC descriptor class, subclass and protocol, break out if correct control interface found */
 192                 if ((DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Class    == CDC_CONTROL_CLASS)    &&
 193                     (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).SubClass == CDC_CONTROL_SUBCLASS) &&
 194                     (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Protocol == CDC_CONTROL_PROTOCOL))
 195                 {
 196                         return DESCRIPTOR_SEARCH_Found;
 197                 }
 198         }
 199
 200         return DESCRIPTOR_SEARCH_NotFound;
 201 }
 202
 203 /** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
 204  *  configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
 205  *  descriptor processing if an incompatible descriptor configuration is found.
 206  *
 207  *  This comparator searches for the next Interface descriptor of the correct CDC data Class, Subclass and Protocol values.
 208  *
 209  *  \return A value from the DSEARCH_Return_ErrorCodes_t enum
 210  */
 211 uint8_t DComp_NextCDCDataInterface(void* CurrentDescriptor)
 212 {
 213         if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
 214         {
 215                 /* Check the CDC descriptor class, subclass and protocol, break out if correct data interface found */
 216                 if ((DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Class    == CDC_DATA_CLASS)    &&
 217                     (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).SubClass == CDC_DATA_SUBCLASS) &&
 218                     (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Protocol == CDC_DATA_PROTOCOL))
 219                 {
 220                         return DESCRIPTOR_SEARCH_Found;
 221                 }
 222         }
 223
 224         return DESCRIPTOR_SEARCH_NotFound;
 225 }
 226
 227 /** Descriptor comparator function. This comparator function is can be called while processing an attached USB device's
 228  *  configuration descriptor, to search for a specific sub descriptor. It can also be used to abort the configuration
 229  *  descriptor processing if an incompatible descriptor configuration is found.
 230  *
 231  *  This comparator searches for the next bulk IN or OUT endpoint, or interrupt IN endpoint within the current interface,
 232  *  aborting the search if another interface descriptor is found before the required endpoint (so that it may be compared
 233  *  using a different comparator to determine if it is another CDC class interface).
 234  *
 235  *  \return A value from the DSEARCH_Return_ErrorCodes_t enum
 236  */
 237 uint8_t DComp_NextCDCDataInterfaceEndpoint(void* CurrentDescriptor)
 238 {
 239         if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint)
 240         {
 241                 uint8_t EndpointType = (DESCRIPTOR_CAST(CurrentDescriptor,
 242                                                         USB_Descriptor_Endpoint_t).Attributes & EP_TYPE_MASK);
 243
 244                 if ((EndpointType == EP_TYPE_BULK) || (EndpointType == EP_TYPE_INTERRUPT))
 245                   return DESCRIPTOR_SEARCH_Found;
 246         }
 247         else if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
 248         {
 249                 return DESCRIPTOR_SEARCH_Fail;
 250         }
 251
 252         return DESCRIPTOR_SEARCH_NotFound;
 253 }