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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 Human Interface Device (HID) Class report descriptor parser.
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 *
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 *  This file allows for the easy parsing of complex HID report descriptors, which describes the data that
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 *  a HID device transmits to the host. It also provides an easy API for extracting and processing the data
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 *  elements inside a HID report sent from an attached HID device.
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 */
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/** \ingroup Group_USB
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 *  \defgroup Group_HIDParser HID Report Parser
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 *  \brief USB Human Interface Device (HID) Class report descriptor parser.
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 *
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 *  \section Sec_Dependencies Module Source Dependencies
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 *  The following files must be built with any user project that uses this module:
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 *    - LUFA/Drivers/USB/Class/Host/HIDParser.c <i>(Makefile source module name: LUFA_SRC_USB)</i>
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 *
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 *  \section Sec_ModDescription Module Description
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 *  Human Interface Device (HID) class report descriptor parser. This module implements a parser than is
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 *  capable of processing a complete HID report descriptor, and outputting a flat structure containing the
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 *  contents of the report in an a more friendly format. The parsed data may then be further processed and used
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 *  within an application to process sent and received HID reports to and from an attached HID device.
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 *
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 *  A HID report descriptor consists of a set of HID report items, which describe the function and layout
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 *  of data exchanged between a HID device and a host, including both the physical encoding of each item
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 *  (such as a button, key press or joystick axis) in the sent and received data packets - known as "reports" -
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 *  as well as other information about each item such as the usages, data range, physical location and other
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 *  characteristics. In this way a HID device can retain a high degree of flexibility in its capabilities, as it
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 *  is not forced to comply with a given report layout or feature-set.
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 *
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 *  This module also contains routines for the processing of data in an actual HID report, using the parsed report
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 *  descriptor data as a guide for the encoding.
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 *
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 *  @{
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 */
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#ifndef __HIDPARSER_H__
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#define __HIDPARSER_H__
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        /* Includes: */
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                #include "../../../../Common/Common.h"
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                #include "HIDReportData.h"
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                #include "../Common/HID.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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        /* Macros: */
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                #if !defined(HID_STATETABLE_STACK_DEPTH) || defined(__DOXYGEN__)
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                        /** Constant indicating the maximum stack depth of the state table. A larger state table
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                         *  allows for more PUSH/POP report items to be nested, but consumes more memory. By default
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                         *  this is set to 2 levels (allowing non-nested PUSH items) but this can be overridden by
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                         *  defining \c HID_STATETABLE_STACK_DEPTH to another value in the user project makefile, passing the
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                         *  define to the compiler using the -D compiler switch.
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                         */
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                        #define HID_STATETABLE_STACK_DEPTH    2
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                #endif
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                #if !defined(HID_USAGE_STACK_DEPTH) || defined(__DOXYGEN__)
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                        /** Constant indicating the maximum stack depth of the usage table. A larger usage table
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                         *  allows for more USAGE items to be indicated sequentially for REPORT COUNT entries of more than
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                         *  one, but requires more stack space. By default this is set to 8 levels (allowing for a report
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                         *  item with a count of 8) but this can be overridden by defining \c HID_USAGE_STACK_DEPTH to another
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                         *  value in the user project makefile, passing the define to the compiler using the -D compiler
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                         *  switch.
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                         */
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                        #define HID_USAGE_STACK_DEPTH         8
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                #endif
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                #if !defined(HID_MAX_COLLECTIONS) || defined(__DOXYGEN__)
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                        /** Constant indicating the maximum number of COLLECTION items (nested or unnested) that can be
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                         *  processed in the report item descriptor. A large value allows for more COLLECTION items to be
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                         *  processed, but consumes more memory. By default this is set to 10 collections, but this can be
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                         *  overridden by defining \c HID_MAX_COLLECTIONS to another value in the user project makefile, passing
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                         *  the define to the compiler using the -D compiler switch.
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                         */
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                        #define HID_MAX_COLLECTIONS           10
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                #endif
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                #if !defined(HID_MAX_REPORTITEMS) || defined(__DOXYGEN__)
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                        /** Constant indicating the maximum number of report items (IN, OUT or FEATURE) that can be processed
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                         *  in the report item descriptor and stored in the user HID Report Info structure. A large value allows
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                         *  for more report items to be stored, but consumes more memory. By default this is set to 20 items,
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                         *  but this can be overridden by defining \c HID_MAX_REPORTITEMS to another value in the user project
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                         *  makefile, and passing the define to the compiler using the -D compiler switch.
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                         */
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                        #define HID_MAX_REPORTITEMS           20
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                #endif
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                #if !defined(HID_MAX_REPORT_IDS) || defined(__DOXYGEN__)
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                        /** Constant indicating the maximum number of unique report IDs that can be processed in the report item
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                         *  descriptor for the report size information array in the user HID Report Info structure. A large value
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                         *  allows for more report ID report sizes to be stored, but consumes more memory. By default this is set
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                         *  to 10 items, but this can be overridden by defining \c HID_MAX_REPORT_IDS to another value in the user project
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                         *  makefile, and passing the define to the compiler using the -D compiler switch. Note that IN, OUT and FEATURE
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                         *  items sharing the same report ID consume only one size item in the array.
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                         */
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                        #define HID_MAX_REPORT_IDS            10
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                #endif
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                /** Returns the value a given HID report item (once its value has been fetched via \ref USB_GetHIDReportItemInfo())
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                 *  left-aligned to the given data type. This allows for signed data to be interpreted correctly, by shifting the data
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                 *  leftwards until the data's sign bit is in the correct position.
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                 *
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                 *  \param[in] ReportItem  HID Report Item whose retrieved value is to be aligned.
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                 *  \param[in] Type        Data type to align the HID report item's value to.
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                 *
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                 *  \return Left-aligned data of the given report item's pre-retrieved value for the given datatype.
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                 */
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                #define HID_ALIGN_DATA(ReportItem, Type) ((Type)(ReportItem->Value << ((8 * sizeof(Type)) - ReportItem->Attributes.BitSize)))
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        /* Public Interface - May be used in end-application: */
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                /* Enums: */
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                        /** Enum for the possible error codes in the return value of the \ref USB_ProcessHIDReport() function. */
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                        enum HID_Parse_ErrorCodes_t
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                        {
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                                HID_PARSE_Successful                  = 0, /**< Successful parse of the HID report descriptor, no error. */
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                                HID_PARSE_HIDStackOverflow            = 1, /**< More than \ref HID_STATETABLE_STACK_DEPTH nested PUSHes in the report. */
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                                HID_PARSE_HIDStackUnderflow           = 2, /**< A POP was found when the state table stack was empty. */
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                                HID_PARSE_InsufficientReportItems     = 3, /**< More than \ref HID_MAX_REPORTITEMS report items in the report. */
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                                HID_PARSE_UnexpectedEndCollection     = 4, /**< An END COLLECTION item found without matching COLLECTION item. */
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                                HID_PARSE_InsufficientCollectionPaths = 5, /**< More than \ref HID_MAX_COLLECTIONS collections in the report. */
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                                HID_PARSE_UsageListOverflow           = 6, /**< More than \ref HID_USAGE_STACK_DEPTH usages listed in a row. */
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                                HID_PARSE_InsufficientReportIDItems   = 7, /**< More than \ref HID_MAX_REPORT_IDS report IDs in the device. */
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                                HID_PARSE_NoUnfilteredReportItems     = 8, /**< All report items from the device were filtered by the filtering callback routine. */
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                        };
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                /* Type Defines: */
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                        /** \brief HID Parser Report Item Min/Max Structure.
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                         *
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                         *  Type define for an attribute with both minimum and maximum values (e.g. Logical Min/Max).
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                         */
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                        typedef struct
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                        {
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                                uint32_t Minimum; /**< Minimum value for the attribute. */
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                                uint32_t Maximum; /**< Maximum value for the attribute. */
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                        } HID_MinMax_t;
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                        /** \brief HID Parser Report Item Unit Structure.
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                         *
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                         *  Type define for the Unit attributes of a report item.
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                         */
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                        typedef struct
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                        {
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                                uint32_t Type;     /**< Unit type (refer to HID specifications for details). */
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                                uint8_t  Exponent; /**< Unit exponent (refer to HID specifications for details). */
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                        } HID_Unit_t;
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                        /** \brief HID Parser Report Item Usage Structure.
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                         *
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                         *  Type define for the Usage attributes of a report item.
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                         */
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                        typedef struct
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                        {
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                                uint16_t Page;  /**< Usage page of the report item. */
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                                uint16_t Usage; /**< Usage of the report item. */
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                        } HID_Usage_t;
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                        /** \brief HID Parser Report Item Collection Path Structure.
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                         *
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                         *  Type define for a COLLECTION object. Contains the collection attributes and a reference to the
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                         *  parent collection if any.
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                         */
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                        typedef struct HID_CollectionPath
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                        {
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                                uint8_t                    Type;   /**< Collection type (e.g. "Generic Desktop"). */
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                                HID_Usage_t                Usage;  /**< Collection usage. */
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                                struct HID_CollectionPath* Parent; /**< Reference to parent collection, or \c NULL if root collection. */
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                        } HID_CollectionPath_t;
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                        /** \brief HID Parser Report Item Attributes Structure.
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                         *
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                         *  Type define for all the data attributes of a report item, except flags.
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                         */
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                        typedef struct
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                        {
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                                uint8_t      BitSize;  /**< Size in bits of the report item's data. */
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                                HID_Usage_t  Usage;    /**< Usage of the report item. */
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                                HID_Unit_t   Unit;     /**< Unit type and exponent of the report item. */
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                                HID_MinMax_t Logical;  /**< Logical minimum and maximum of the report item. */
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                                HID_MinMax_t Physical; /**< Physical minimum and maximum of the report item. */
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                        } HID_ReportItem_Attributes_t;
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                        /** \brief HID Parser Report Item Details Structure.
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                         *
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                         *  Type define for a report item (IN, OUT or FEATURE) layout attributes and other details.
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                         */
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                        typedef struct
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                        {
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                                uint16_t                    BitOffset;      /**< Bit offset in the IN, OUT or FEATURE report of the item. */
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                                uint8_t                     ItemType;       /**< Report item type, a value in \ref HID_ReportItemTypes_t. */
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                                uint16_t                    ItemFlags;      /**< Item data flags, a mask of HID_IOF_* constants. */
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                                uint8_t                     ReportID;       /**< Report ID this item belongs to, or 0x00 if device has only one report */
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                                HID_CollectionPath_t*       CollectionPath; /**< Collection path of the item. */
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                                HID_ReportItem_Attributes_t Attributes;     /**< Report item attributes. */
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                                uint32_t                    Value;          /**< Current value of the report item - use \ref HID_ALIGN_DATA() when processing
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                                                                             *   a retrieved value so that it is aligned to a specific type.
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                                                                             */
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                                uint32_t                    PreviousValue;  /**< Previous value of the report item. */
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                        } HID_ReportItem_t;
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                        /** \brief HID Parser Report Size Structure.
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                         *
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                         *  Type define for a report item size information structure, to retain the size of a device's reports by ID.
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                         */
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                        typedef struct
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                        {
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                                uint8_t  ReportID; /**< Report ID of the report within the HID interface. */
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                                uint16_t ReportSizeBits[3]; /**< Total number of bits in each report type for the given Report ID,
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                                                             *   indexed by the \ref HID_ReportItemTypes_t enum.
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                                                             */
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                        } HID_ReportSizeInfo_t;
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                        /** \brief HID Parser State Structure.
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                         *
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                         *  Type define for a complete processed HID report, including all report item data and collections.
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                         */
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                        typedef struct
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                        {
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                                uint8_t              TotalReportItems; /**< Total number of report items stored in the \c ReportItems array. */
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                                HID_ReportItem_t     ReportItems[HID_MAX_REPORTITEMS]; /**< Report items array, including all IN, OUT
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                                                                                    *   and FEATURE items.
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                                                                                        */
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                                HID_CollectionPath_t CollectionPaths[HID_MAX_COLLECTIONS]; /**< All collection items, referenced
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                                                                                            *   by the report items.
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                                                                                            */
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                                uint8_t              TotalDeviceReports; /**< Number of reports within the HID interface */
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                                HID_ReportSizeInfo_t ReportIDSizes[HID_MAX_REPORT_IDS]; /**< Report sizes for each report in the interface */
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                                uint16_t             LargestReportSizeBits; /**< Largest report that the attached device will generate, in bits */
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                                bool                 UsingReportIDs; /**< Indicates if the device has at least one REPORT ID
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                                                                      *   element in its HID report descriptor.
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                                                                      */
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                        } HID_ReportInfo_t;
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                /* Function Prototypes: */
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                        /** Function to process a given HID report returned from an attached device, and store it into a given
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                         *  \ref HID_ReportInfo_t structure.
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                         *
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                         *  \param[in]  ReportData  Buffer containing the device's HID report table.
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                         *  \param[in]  ReportSize  Size in bytes of the HID report table.
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                         *  \param[out] ParserData  Pointer to a \ref HID_ReportInfo_t instance for the parser output.
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                         *
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                         *  \return A value in the \ref HID_Parse_ErrorCodes_t enum.
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                         */
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                        uint8_t USB_ProcessHIDReport(const uint8_t* ReportData,
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                                                     uint16_t ReportSize,
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                                                     HID_ReportInfo_t* const ParserData) ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(3);
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                        /** Extracts the given report item's value out of the given HID report and places it into the Value
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                         *  member of the report item's \ref HID_ReportItem_t structure.
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                         *
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                         *  When called on a report with an item that exists in that report, this copies the report item's \c Value
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                         *  to its \c PreviousValue element for easy checking to see if an item's value has changed before processing
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                         *  a report. If the given item does not exist in the report, the function does not modify the report item's
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                         *  data.
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                         *
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                         *  \param[in]     ReportData  Buffer containing an IN or FEATURE report from an attached device.
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                         *  \param[in,out] ReportItem  Pointer to the report item of interest in a \ref HID_ReportInfo_t ReportItem array.
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                         *
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                         *  \returns Boolean \c true if the item to retrieve was located in the given report, \c false otherwise.
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                         */
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                        bool USB_GetHIDReportItemInfo(const uint8_t* ReportData,
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                                                      HID_ReportItem_t* const ReportItem) ATTR_NON_NULL_PTR_ARG(1);
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                        /** Retrieves the given report item's value out of the \c Value member of the report item's
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                         *  \ref HID_ReportItem_t structure and places it into the correct position in the HID report
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                         *  buffer. The report buffer is assumed to have the appropriate bits cleared before calling
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                         *  this function (i.e., the buffer should be explicitly cleared before report values are added).
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                         *
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                         *  When called, this copies the report item's \c Value element to its \c PreviousValue element for easy
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                         *  checking to see if an item's value has changed before sending a report.
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                         *
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                         *  If the device has multiple HID reports, the first byte in the report is set to the report ID of the given item.
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                         *
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                         *  \param[out] ReportData  Buffer holding the current OUT or FEATURE report data.
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                         *  \param[in]  ReportItem  Pointer to the report item of interest in a \ref HID_ReportInfo_t ReportItem array.
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                         */
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                        void USB_SetHIDReportItemInfo(uint8_t* ReportData,
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                                                      HID_ReportItem_t* const ReportItem) ATTR_NON_NULL_PTR_ARG(1);
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                        /** Retrieves the size of a given HID report in bytes from its Report ID.
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                         *
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                         *  \param[in] ParserData  Pointer to a \ref HID_ReportInfo_t instance containing the parser output.
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                         *  \param[in] ReportID    Report ID of the report whose size is to be determined.
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                         *  \param[in] ReportType  Type of the report whose size is to be determined, a value from the
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                         *                         \ref HID_ReportItemTypes_t enum.
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                         *
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                         *  \return Size of the report in bytes, or \c 0 if the report does not exist.
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                         */
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                        uint16_t USB_GetHIDReportSize(HID_ReportInfo_t* const ParserData,
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                                                      const uint8_t ReportID,
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                                                      const uint8_t ReportType) ATTR_CONST ATTR_NON_NULL_PTR_ARG(1);
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                        /** Callback routine for the HID Report Parser. This callback <b>must</b> be implemented by the user code when
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                         *  the parser is used, to determine what report IN, OUT and FEATURE item's information is stored into the user
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                         *  \ref HID_ReportInfo_t structure. This can be used to filter only those items the application will be using, so that
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                         *  no RAM is wasted storing the attributes for report items which will never be referenced by the application.
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                         *
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                         *  Report item pointers passed to this callback function may be cached by the user application for later use
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                         *  when processing report items. This provides faster report processing in the user application than would
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                         *  a search of the entire parsed report item table for each received or sent report.
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                         *
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                         *  \param[in] CurrentItem  Pointer to the current report item for user checking.
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                         *
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                         *  \return Boolean \c true if the item should be stored into the \ref HID_ReportInfo_t structure, \c false if
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                         *          it should be ignored.
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                         */
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                        bool CALLBACK_HIDParser_FilterHIDReportItem(HID_ReportItem_t* const CurrentItem);
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        /* Private Interface - For use in library only: */
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        #if !defined(__DOXYGEN__)
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                /* Type Defines: */
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                        typedef struct
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                        {
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                                 HID_ReportItem_Attributes_t Attributes;
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                                 uint8_t                     ReportCount;
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                                 uint8_t                     ReportID;
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                        } HID_StateTable_t;
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        #endif
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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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