Documentation improvements - put driver example code into its own section, fix incorr...
[pub/USBasp.git] / Demos / Host / LowLevel / StillImageHost / ConfigDescriptor.c
index 583df3b..e11fc17 100644 (file)
@@ -1,21 +1,21 @@
 /*
              LUFA Library
      Copyright (C) Dean Camera, 2010.
-              
+
   dean [at] fourwalledcubicle [dot] com
-      www.fourwalledcubicle.com
+           www.lufa-lib.org
 */
 
 /*
   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
 
-  Permission to use, copy, modify, distribute, and sell this 
+  Permission to use, copy, modify, distribute, and sell this
   software and its documentation for any purpose is hereby granted
-  without fee, provided that the above copyright notice appear in 
+  without fee, provided that the above copyright notice appear in
   all copies and that both that the copyright notice and this
-  permission notice and warranty disclaimer appear in supporting 
-  documentation, and that the name of the author not be used in 
-  advertising or publicity pertaining to distribution of the 
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
   software without specific, written prior permission.
 
   The author disclaim all warranties with regard to this
@@ -50,10 +50,11 @@ uint8_t ProcessConfigurationDescriptor(void)
        uint8_t  ConfigDescriptorData[512];
        void*    CurrConfigLocation = ConfigDescriptorData;
        uint16_t CurrConfigBytesRem;
-       
-       USB_Descriptor_Endpoint_t* DataINEndpoint  = NULL;
-       USB_Descriptor_Endpoint_t* DataOUTEndpoint = NULL;
-       USB_Descriptor_Endpoint_t* EventsEndpoint  = NULL;
+
+       USB_Descriptor_Interface_t* StillImageInterface = NULL;
+       USB_Descriptor_Endpoint_t*  DataINEndpoint      = NULL;
+       USB_Descriptor_Endpoint_t*  DataOUTEndpoint     = NULL;
+       USB_Descriptor_Endpoint_t*  EventsEndpoint      = NULL;
 
        /* Retrieve the entire configuration descriptor into the allocated buffer */
        switch (USB_Host_GetDeviceConfigDescriptor(1, &CurrConfigBytesRem, ConfigDescriptorData, sizeof(ConfigDescriptorData)))
@@ -67,26 +68,14 @@ uint8_t ProcessConfigurationDescriptor(void)
                default:
                        return ControlError;
        }
-       
-       /* Get the first Still Image interface from the configuration descriptor */
-       if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
-                                     DComp_NextStillImageInterface) != DESCRIPTOR_SEARCH_COMP_Found)
-       {
-               /* Descriptor not found, error out */
-               return NoCompatibleInterfaceFound;
-       }
 
        while (!(DataINEndpoint) || !(DataOUTEndpoint))
        {
-               /* Get the next Still Image interface's data endpoint descriptor */
-               if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+               /* See if we've found a likely compatible interface, and if there is an endpoint within that interface */
+               if (!(StillImageInterface) ||
+                   USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
                                              DComp_NextStillImageInterfaceDataEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
                {
-                       /* Clear any found endpoints */
-                       DataINEndpoint  = NULL;
-                       DataOUTEndpoint = NULL;
-                       EventsEndpoint  = NULL;
-
                        /* Get the next Still Image interface from the configuration descriptor */
                        if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
                                                                                  DComp_NextStillImageInterface) != DESCRIPTOR_SEARCH_COMP_Found)
@@ -94,6 +83,17 @@ uint8_t ProcessConfigurationDescriptor(void)
                                /* Descriptor not found, error out */
                                return NoCompatibleInterfaceFound;
                        }
+
+                       /* Save the interface in case we need to refer back to it later */
+                       StillImageInterface = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Interface_t);
+
+                       /* Clear any found endpoints */
+                       DataINEndpoint  = NULL;
+                       DataOUTEndpoint = NULL;
+                       EventsEndpoint  = NULL;
+
+                       /* Skip the remainder of the loop as we have not found an endpoint yet */
+                       continue;
                }
 
                /* Retrieve the endpoint address from the endpoint descriptor */
@@ -113,7 +113,7 @@ uint8_t ProcessConfigurationDescriptor(void)
                        DataOUTEndpoint = EndpointData;
                }
        }
-       
+
        /* Configure the Still Image data IN pipe */
        Pipe_ConfigurePipe(SIMAGE_DATA_IN_PIPE, EP_TYPE_BULK, PIPE_TOKEN_IN,
                           DataINEndpoint->EndpointAddress, DataINEndpoint->EndpointSize, PIPE_BANK_SINGLE);
@@ -141,17 +141,21 @@ uint8_t ProcessConfigurationDescriptor(void)
  */
 uint8_t DComp_NextStillImageInterface(void* CurrentDescriptor)
 {
-       if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
+       USB_Descriptor_Header_t* Header = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Header_t);
+
+       if (Header->Type == DTYPE_Interface)
        {
-               /* Check the descriptor class and protocol, break out if correct class/protocol interface found */
-               if ((DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Class    == SIMAGE_CLASS)    &&
-                   (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).SubClass == SIMAGE_SUBCLASS) &&
-                   (DESCRIPTOR_CAST(CurrentDescriptor, USB_Descriptor_Interface_t).Protocol == SIMAGE_PROTOCOL))
+               USB_Descriptor_Interface_t* Interface = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Interface_t);
+
+               /* Check the descriptor class, subclass and protocol, break out if correct interface found */
+               if ((Interface->Class    == SI_CSCP_StillImageClass)    &&
+                   (Interface->SubClass == SI_CSCP_StillImageSubclass) &&
+                   (Interface->Protocol == SI_CSCP_BulkOnlyProtocol))
                {
                        return DESCRIPTOR_SEARCH_Found;
                }
        }
-       
+
        return DESCRIPTOR_SEARCH_NotFound;
 }
 
@@ -166,18 +170,24 @@ uint8_t DComp_NextStillImageInterface(void* CurrentDescriptor)
  */
 uint8_t DComp_NextStillImageInterfaceDataEndpoint(void* CurrentDescriptor)
 {
-       if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint)
+       USB_Descriptor_Header_t* Header = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Header_t);
+
+       if (Header->Type == DTYPE_Endpoint)
        {
-               uint8_t EndpointType = (DESCRIPTOR_CAST(CurrentDescriptor,
-                                                       USB_Descriptor_Endpoint_t).Attributes & EP_TYPE_MASK);
-       
-               if ((EndpointType == EP_TYPE_BULK) || (EndpointType == EP_TYPE_INTERRUPT))
-                 return DESCRIPTOR_SEARCH_Found;
+               USB_Descriptor_Endpoint_t* Endpoint = DESCRIPTOR_PCAST(CurrentDescriptor, USB_Descriptor_Endpoint_t);
+
+               /* Check the endpoint type, break out if correct BULK or INTERRUPT type endpoint found */
+               if (((Endpoint->Attributes & EP_TYPE_MASK) == EP_TYPE_BULK) || 
+                   ((Endpoint->Attributes & EP_TYPE_MASK) == EP_TYPE_INTERRUPT))
+               {
+                       return DESCRIPTOR_SEARCH_Found;
+               }
        }
-       else if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Interface)
+       else if (Header->Type == DTYPE_Interface)
        {
                return DESCRIPTOR_SEARCH_Fail;
        }
 
        return DESCRIPTOR_SEARCH_NotFound;
 }
+