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/*
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             LUFA Library
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     Copyright (C) Dean Camera, 2011.
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  dean [at] fourwalledcubicle [dot] com
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           www.lufa-lib.org
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*/
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/*
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  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
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  Permission to use, copy, modify, distribute, and sell this
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  software and its documentation for any purpose is hereby granted
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  without fee, provided that the above copyright notice appear in
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  all copies and that both that the copyright notice and this
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  permission notice and warranty disclaimer appear in supporting
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  documentation, and that the name of the author not be used in
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  advertising or publicity pertaining to distribution of the
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  software without specific, written prior permission.
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  The author disclaim all warranties with regard to this
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  software, including all implied warranties of merchantability
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  and fitness.  In no event shall the author be liable for any
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  special, indirect or consequential damages or any damages
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  whatsoever resulting from loss of use, data or profits, whether
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  in an action of contract, negligence or other tortious action,
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  arising out of or in connection with the use or performance of
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  this software.
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*/
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/** \file
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 *  \brief USB Configuration Descriptor definitions.
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 *  \copydetails Group_ConfigDescriptorParser
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 *
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 *  \note This file should not be included directly. It is automatically included as needed by the USB driver
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 *        dispatch header located in LUFA/Drivers/USB/USB.h.
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 */
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/** \ingroup Group_Descriptors
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 *  \defgroup Group_ConfigDescriptorParser Configuration Descriptor Parser
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 *  \brief USB Configuration Descriptor definitions.
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 *
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 *  This section of the library gives a friendly API which can be used in host applications to easily
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 *  parse an attached device's configuration descriptor so that endpoint, interface and other descriptor
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 *  data can be extracted and used as needed.
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 *
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 *  @{
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 */
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#ifndef __CONFIGDESCRIPTOR_H__
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#define __CONFIGDESCRIPTOR_H__
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        /* Includes: */
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                #include "../../../Common/Common.h"
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                #include "USBMode.h"                
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                #include "HostStandardReq.h"
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                #include "StdDescriptors.h"
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        /* Enable C linkage for C++ Compilers: */
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                #if defined(__cplusplus)
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                        extern "C" {
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                #endif
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        /* Preprocessor Checks: */
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                #if !defined(__INCLUDE_FROM_USB_DRIVER)
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                        #error Do not include this file directly. Include LUFA/Drivers/USB/USB.h instead.
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                #endif
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        /* Public Interface - May be used in end-application: */
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                /* Macros: */
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                        /** Casts a pointer to a descriptor inside the configuration descriptor into a pointer to the given
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                         *  descriptor type.
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                         *
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                         *  Usage Example:
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                         *  \code
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                         *  uint8_t* CurrDescriptor = &ConfigDescriptor[0]; // Pointing to the configuration header
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                         *  USB_Descriptor_Configuration_Header_t* ConfigHeaderPtr = DESCRIPTOR_PCAST(CurrDescriptor,
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                         *                                                           USB_Descriptor_Configuration_Header_t);
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                         *
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                         *  // Can now access elements of the configuration header struct using the -> indirection operator
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                         *  \endcode
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                         */
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                        #define DESCRIPTOR_PCAST(DescriptorPtr, Type) ((Type*)(DescriptorPtr))
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                        /** Casts a pointer to a descriptor inside the configuration descriptor into the given descriptor
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                         *  type (as an actual struct instance rather than a pointer to a struct).
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                         *
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                         *  Usage Example:
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                         *  \code
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                         *  uint8_t* CurrDescriptor = &ConfigDescriptor[0]; // Pointing to the configuration header
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                         *  USB_Descriptor_Configuration_Header_t ConfigHeader = DESCRIPTOR_CAST(CurrDescriptor,
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                         *                                                       USB_Descriptor_Configuration_Header_t);
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                         *
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                         *  // Can now access elements of the configuration header struct using the . operator
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                         *  \endcode
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                         */
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                        #define DESCRIPTOR_CAST(DescriptorPtr, Type)  (*DESCRIPTOR_PCAST(DescriptorPtr, Type))
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                        /** Returns the descriptor's type, expressed as the 8-bit type value in the header of the descriptor.
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                         *  This value's meaning depends on the descriptor's placement in the descriptor, but standard type
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                         *  values can be accessed in the \ref USB_DescriptorTypes_t enum.
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                         */
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                        #define DESCRIPTOR_TYPE(DescriptorPtr)    DESCRIPTOR_PCAST(DescriptorPtr, USB_Descriptor_Header_t)->Type
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                        /** Returns the descriptor's size, expressed as the 8-bit value indicating the number of bytes. */
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                        #define DESCRIPTOR_SIZE(DescriptorPtr)    DESCRIPTOR_PCAST(DescriptorPtr, USB_Descriptor_Header_t)->Size
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                /* Type Defines: */
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                        /** Type define for a Configuration Descriptor comparator function (function taking a pointer to an array
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                         *  of type void, returning a uint8_t value).
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                         *
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                         *  \see \ref USB_GetNextDescriptorComp function for more details.
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                         */
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                        typedef uint8_t (* ConfigComparatorPtr_t)(void*);
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                /* Enums: */
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                        /** Enum for the possible return codes of the \ref USB_Host_GetDeviceConfigDescriptor() function. */
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                        enum USB_Host_GetConfigDescriptor_ErrorCodes_t
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                        {
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                                HOST_GETCONFIG_Successful       = 0, /**< No error occurred while retrieving the configuration descriptor. */
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                                HOST_GETCONFIG_DeviceDisconnect = 1, /**< The attached device was disconnected while retrieving the configuration
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                                                                        * descriptor.
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                                                                        */
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                                HOST_GETCONFIG_PipeError        = 2, /**< An error occurred in the pipe while sending the request. */
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                                HOST_GETCONFIG_SetupStalled     = 3, /**< The attached device stalled the request to retrieve the configuration
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                                                                        * descriptor.
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                                                                        */
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                                HOST_GETCONFIG_SoftwareTimeOut  = 4, /**< The request or data transfer timed out. */
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                                HOST_GETCONFIG_BuffOverflow     = 5, /**< The device's configuration descriptor is too large to fit into the allocated
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                                                                        * buffer.
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                                                                        */
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                                HOST_GETCONFIG_InvalidData      = 6, /**< The device returned invalid configuration descriptor data. */
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                        };
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                        /** Enum for return values of a descriptor comparator function. */
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                        enum DSearch_Return_ErrorCodes_t
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                        {
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                                DESCRIPTOR_SEARCH_Found                = 0, /**< Current descriptor matches comparator criteria. */
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                                DESCRIPTOR_SEARCH_Fail                 = 1, /**< No further descriptor could possibly match criteria, fail the search. */
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                                DESCRIPTOR_SEARCH_NotFound             = 2, /**< Current descriptor does not match comparator criteria. */
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                        };
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                        /** Enum for return values of \ref USB_GetNextDescriptorComp(). */
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                        enum DSearch_Comp_Return_ErrorCodes_t
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                        {
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                                DESCRIPTOR_SEARCH_COMP_Found           = 0, /**< Configuration descriptor now points to descriptor which matches
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                                                                             *   search criteria of the given comparator function. */
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                                DESCRIPTOR_SEARCH_COMP_Fail            = 1, /**< Comparator function returned \ref DESCRIPTOR_SEARCH_Fail. */
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                                DESCRIPTOR_SEARCH_COMP_EndOfDescriptor = 2, /**< End of configuration descriptor reached before match found. */
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                        };
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                /* Function Prototypes: */
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                        /** Retrieves the configuration descriptor data from an attached device via a standard request into a buffer,
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                         *  including validity and size checking to prevent a buffer overflow.
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                         *
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                         *  \param[in]     ConfigNumber   Device configuration descriptor number to fetch from the device (usually set to 1 for
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                         *                                single configuration devices).
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                         *  \param[in,out] ConfigSizePtr  Pointer to a location for storing the retrieved configuration descriptor size.
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                         *  \param[out]    BufferPtr      Pointer to the buffer for storing the configuration descriptor data.
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                         *  \param[out]    BufferSize     Size of the allocated buffer where the configuration descriptor is to be stored.
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                         *
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                         *  \return A value from the \ref USB_Host_GetConfigDescriptor_ErrorCodes_t enum.
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                         */
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                        uint8_t USB_Host_GetDeviceConfigDescriptor(const uint8_t ConfigNumber,
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                                                                   uint16_t* const ConfigSizePtr,
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                                                                   void* const BufferPtr,
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                                                                   const uint16_t BufferSize) ATTR_NON_NULL_PTR_ARG(2) ATTR_NON_NULL_PTR_ARG(3);
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                        /** Skips to the next sub-descriptor inside the configuration descriptor of the specified type value.
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                         *  The bytes remaining value is automatically decremented.
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                         *
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                         * \param[in,out] BytesRem       Pointer to the number of bytes remaining of the configuration descriptor.
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                         * \param[in,out] CurrConfigLoc  Pointer to the current descriptor inside the configuration descriptor.
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                         * \param[in]     Type           Descriptor type value to search for.
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                         */
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                        void USB_GetNextDescriptorOfType(uint16_t* const BytesRem,
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                                                         void** const CurrConfigLoc,
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                                                         const uint8_t Type)
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                                                         ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
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                        /** Skips to the next sub-descriptor inside the configuration descriptor of the specified type value,
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                         *  which must come before a descriptor of the second given type value. If the BeforeType type
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                         *  descriptor is reached first, the number of bytes remaining to process is set to zero and the
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                         *  function exits. The bytes remaining value is automatically decremented.
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                         *
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                         * \param[in,out] BytesRem       Pointer to the number of bytes remaining of the configuration descriptor.
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                         * \param[in,out] CurrConfigLoc  Pointer to the current descriptor inside the configuration descriptor.
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                         * \param[in]     Type           Descriptor type value to search for.
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                         * \param[in]     BeforeType     Descriptor type value which must not be reached before the given Type descriptor.
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                         */
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                        void USB_GetNextDescriptorOfTypeBefore(uint16_t* const BytesRem,
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                                                               void** const CurrConfigLoc,
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                                                               const uint8_t Type,
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                                                               const uint8_t BeforeType)
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                                                               ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
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                        /** Skips to the next sub-descriptor inside the configuration descriptor of the specified type value,
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                         *  which must come after a descriptor of the second given type value. The bytes remaining value is
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                         *  automatically decremented.
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                         *
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                         * \param[in,out] BytesRem       Pointer to the number of bytes remaining of the configuration descriptor.
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                         * \param[in,out] CurrConfigLoc  Pointer to the current descriptor inside the configuration descriptor.
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                         * \param[in]     Type           Descriptor type value to search for.
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                         * \param[in]     AfterType      Descriptor type value which must be reached before the given Type descriptor.
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                         */
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                        void USB_GetNextDescriptorOfTypeAfter(uint16_t* const BytesRem,
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                                                              void** const CurrConfigLoc,
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                                                              const uint8_t Type,
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                                                              const uint8_t AfterType)
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                                                              ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
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                        /** Searches for the next descriptor in the given configuration descriptor using a pre-made comparator
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                         *  function. The routine updates the position and remaining configuration descriptor bytes values
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                         *  automatically. If a comparator routine fails a search, the descriptor pointer is retreated back
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                         *  so that the next descriptor search invocation will start from the descriptor which first caused the
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                         *  original search to fail. This behaviour allows for one comparator to be used immediately after another
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                         *  has failed, starting the second search from the descriptor which failed the first.
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                         *
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                         *  Comparator functions should be standard functions which accept a pointer to the header of the current
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                         *  descriptor inside the configuration descriptor which is being compared, and should return a value from
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                         *  the \ref DSearch_Return_ErrorCodes_t enum as a uint8_t value.
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                         *
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                         *  \note This function is available in USB Host mode only.
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                         *
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                         *  \param[in,out] BytesRem           Pointer to an int storing the remaining bytes in the configuration descriptor.
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                         *  \param[in,out] CurrConfigLoc      Pointer to the current position in the configuration descriptor.
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                         *  \param[in]     ComparatorRoutine  Name of the comparator search function to use on the configuration descriptor.
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                         *
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                         *  \return Value of one of the members of the \ref DSearch_Comp_Return_ErrorCodes_t enum.
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                         *
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                         *  Usage Example:
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                         *  \code
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                         *  uint8_t EndpointSearcher(void* CurrentDescriptor); // Comparator Prototype
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                         *
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                         *  uint8_t EndpointSearcher(void* CurrentDescriptor)
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                         *  {
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                         *     if (DESCRIPTOR_TYPE(CurrentDescriptor) == DTYPE_Endpoint)
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                         *         return DESCRIPTOR_SEARCH_Found;
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                         *     else
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                         *         return DESCRIPTOR_SEARCH_NotFound;
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                         *  }
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                         *
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                         *  //...
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                         *  // After retrieving configuration descriptor:
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                         *  if (USB_Host_GetNextDescriptorComp(&BytesRemaining, &CurrentConfigLoc, EndpointSearcher) ==
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                         *      Descriptor_Search_Comp_Found)
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                         *  {
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                         *      // Do something with the endpoint descriptor
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                         *  }
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                         *  \endcode
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                         */
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                        uint8_t USB_GetNextDescriptorComp(uint16_t* const BytesRem,
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                                                          void** const CurrConfigLoc,
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                                                          ConfigComparatorPtr_t const ComparatorRoutine);
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                /* Inline Functions: */
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                        /** Skips over the current sub-descriptor inside the configuration descriptor, so that the pointer then
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                            points to the next sub-descriptor. The bytes remaining value is automatically decremented.
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                         *
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                         * \param[in,out] BytesRem       Pointer to the number of bytes remaining of the configuration descriptor.
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                         * \param[in,out] CurrConfigLoc  Pointer to the current descriptor inside the configuration descriptor.
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                         */
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                        static inline void USB_GetNextDescriptor(uint16_t* const BytesRem,
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                                                                 void** CurrConfigLoc) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
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                        static inline void USB_GetNextDescriptor(uint16_t* const BytesRem,
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                                                                 void** CurrConfigLoc)
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                        {
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                                uint16_t CurrDescriptorSize = DESCRIPTOR_CAST(*CurrConfigLoc, USB_Descriptor_Header_t).Size;
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                                if (*BytesRem < CurrDescriptorSize)
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                                  CurrDescriptorSize = *BytesRem;
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                                *CurrConfigLoc  = (void*)((uintptr_t)*CurrConfigLoc + CurrDescriptorSize);
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                                *BytesRem      -= CurrDescriptorSize;
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                        }
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        /* Disable C linkage for C++ Compilers: */
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                #if defined(__cplusplus)
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                        }
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                #endif
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#endif
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/** @} */
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