LUFA/Drivers/USB/Class/Host/HIDParser.h

   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 Human Interface Device (HID) Class report descriptor processing routines. This file allows for the easy
  34  *  parsing of the complex HID report descriptor, which describes the data that the device transmits to the host.
  35  *
  36  */
  37
  38 /** \ingroup Group_USB
  39  *  @defgroup Group_HIDParser HID Report Parser
  40  *
  41  *  \section Sec_Dependencies Module Source Dependencies
  42  *  The following files must be built with any user project that uses this module:
  43  *    - LUFA/Drivers/USB/Class/Host/HIDParser.c
  44  *
  45  *  \section Module Description
  46  *  Functions, macros, variables, enums and types related to the parsing of HID class device report descriptors.
  47  *
  48  *  The processed HID report is presented back to the user application as a flat structure containing each report
  49  *  item's IN, OUT and FEATURE items along with each item's attributes.
  50  *
  51  *  This library portion also allows for easy setting and retrieval of data from a HID report, including devices
  52  *  with multiple reports on the one HID interface.
  53  *
  54  *  @{
  55  */
  56
  57 #ifndef __HIDPARSER_H__
  58 #define __HIDPARSER_H__
  59
  60         /* Includes: */
  61                 #include <string.h>
  62                 #include <stdbool.h>
  63
  64                 #include "HIDReportData.h"
  65                 #include "../Common/HID.h"
  66
  67                 #include "../../../../Common/Common.h"
  68
  69         /* Enable C linkage for C++ Compilers: */
  70                 #if defined(__cplusplus)
  71                         extern "C" {
  72                 #endif
  73
  74         /* Macros: */
  75                 #if !defined(HID_STATETABLE_STACK_DEPTH) || defined(__DOXYGEN__)
  76                         /** Constant indicating the maximum stack depth of the state table. A larger state table
  77                          *  allows for more PUSH/POP report items to be nested, but consumes more memory. By default
  78                          *  this is set to 2 levels (allowing non-nested PUSH items) but this can be overridden by
  79                          *  defining HID_STATETABLE_STACK_DEPTH to another value in the user project makefile, passing the
  80                          *  define to the compiler using the -D compiler switch.
  81                          */
  82                         #define HID_STATETABLE_STACK_DEPTH    2
  83                 #endif
  84
  85                 #if !defined(HID_USAGE_STACK_DEPTH) || defined(__DOXYGEN__)
  86                         /** Constant indicating the maximum stack depth of the usage table. A larger usage table
  87                          *  allows for more USAGE items to be indicated sequentially for REPORT COUNT entries of more than
  88                          *  one, but requires more stack space. By default this is set to 8 levels (allowing for a report
  89                          *  item with a count of 8) but this can be overridden by defining HID_USAGE_STACK_DEPTH to another
  90                          *  value in the user project makefile, passing the define to the compiler using the -D compiler
  91                          *  switch.
  92                          */
  93                         #define HID_USAGE_STACK_DEPTH         8
  94                 #endif
  95
  96                 #if !defined(HID_MAX_COLLECTIONS) || defined(__DOXYGEN__)
  97                         /** Constant indicating the maximum number of COLLECTION items (nested or unnested) that can be
  98                          *  processed in the report item descriptor. A large value allows for more COLLECTION items to be
  99                          *  processed, but consumes more memory. By default this is set to 5 collections, but this can be
 100                          *  overridden by defining HID_MAX_COLLECTIONS to another value in the user project makefile, passing
 101                          *  the define to the compiler using the -D compiler switch.
 102                          */
 103                         #define HID_MAX_COLLECTIONS           10
 104                 #endif
 105
 106                 #if !defined(HID_MAX_REPORTITEMS) || defined(__DOXYGEN__)
 107                         /** Constant indicating the maximum number of report items (IN, OUT or FEATURE) that can be processed
 108                          *  in the report item descriptor and stored in the user HID Report Info structure. A large value allows
 109                          *  for more report items to be stored, but consumes more memory. By default this is set to 20 items,
 110                          *  but this can be overridden by defining HID_MAX_REPORTITEMS to another value in the user project
 111                          *  makefile, and passing the define to the compiler using the -D compiler switch.
 112                          */
 113                         #define HID_MAX_REPORTITEMS           20
 114                 #endif
 115
 116                 #if !defined(HID_MAX_REPORT_IDS) || defined(__DOXYGEN__)
 117                         /** Constant indicating the maximum number of unique report IDs that can be processed in the report item
 118                          *  descriptor for the report size information array in the user HID Report Info structure. A large value
 119                          *  allows for more report ID report sizes to be stored, but consumes more memory. By default this is set
 120                          *  to 5 items, but this can be overridden by defining HID_MAX_REPORT_IDS to another value in the user project
 121                          *  makefile, and passing the define to the compiler using the -D compiler switch. Note that IN, OUT and FEATURE
 122                          *  items sharing the same report ID consume only one size item in the array.
 123                          */
 124                         #define HID_MAX_REPORT_IDS            10
 125                 #endif
 126
 127                 /** Returns the value a given HID report item (once its value has been fetched via \ref USB_GetHIDReportItemInfo())
 128                  *  left-aligned to the given data type. This allows for signed data to be interpreted correctly, by shifting the data
 129                  *  leftwards until the data's sign bit is in the correct position.
 130                  *
 131                  *  \param[in] reportitem  HID Report Item whose retrieved value is to be aligned
 132                  *  \param[in] type  Data type to align the HID report item's value to
 133                  *
 134                  *  \return Left-aligned data of the given report item's pre-retrived value for the given datatype
 135                  */
 136                 #define HID_ALIGN_DATA(reportitem, type) ((type)(reportitem->Value << (sizeof(type) - reportitem->Attributes.BitSize)))
 137
 138         /* Public Interface - May be used in end-application: */
 139                 /* Enums: */
 140                         /** Enum for the possible error codes in the return value of the \ref USB_ProcessHIDReport() function */
 141                         enum HID_Parse_ErrorCodes_t
 142                         {
 143                                 HID_PARSE_Successful                  = 0, /**< Successful parse of the HID report descriptor, no error. */
 144                                 HID_PARSE_HIDStackOverflow            = 1, /**< More than \ref HID_STATETABLE_STACK_DEPTH nested PUSHes in the report. */
 145                                 HID_PARSE_HIDStackUnderflow           = 2, /**< A POP was found when the state table stack was empty. */
 146                                 HID_PARSE_InsufficientReportItems     = 3, /**< More than \ref HID_MAX_REPORTITEMS report items in the report. */
 147                                 HID_PARSE_UnexpectedEndCollection     = 4, /**< An END COLLECTION item found without matching COLLECTION item. */
 148                                 HID_PARSE_InsufficientCollectionPaths = 5, /**< More than \ref HID_MAX_COLLECTIONS collections in the report. */
 149                                 HID_PARSE_UsageListOverflow           = 6, /**< More than \ref HID_USAGE_STACK_DEPTH usages listed in a row. */
 150                                 HID_PARSE_InsufficientReportIDItems   = 7, /**< More than \ref HID_MAX_REPORT_IDS report IDs in the device. */
 151                                 HID_PARSE_NoUnfilteredReportItems     = 8, /**< All report items from the device were filtered by the filtering callback routine. */
 152                         };
 153
 154                 /* Type Defines: */
 155                         /** Type define for an attribute with both minimum and maximum values (e.g. Logical Min/Max). */
 156                         typedef struct
 157                         {
 158                                 uint32_t                     Minimum; /**< Minimum value for the attribute. */
 159                                 uint32_t                     Maximum; /**< Maximum value for the attribute. */
 160                         } HID_MinMax_t;
 161
 162                         /** Type define for the Unit attributes of a report item. */
 163                         typedef struct
 164                         {
 165                                 uint32_t                     Type;     /**< Unit type (refer to HID specifications for details). */
 166                                 uint8_t                      Exponent; /**< Unit exponent (refer to HID specifications for details). */
 167                         } HID_Unit_t;
 168
 169                         /** Type define for the Usage attributes of a report item. */
 170                         typedef struct
 171                         {
 172                                 uint16_t                     Page;   /**< Usage page of the report item. */
 173                                 uint16_t                     Usage;  /**< Usage of the report item. */
 174                         } HID_Usage_t;
 175
 176                         /** Type define for a COLLECTION object. Contains the collection attributes and a reference to the
 177                          *  parent collection if any.
 178                          */
 179                         typedef struct CollectionPath
 180                         {
 181                                 uint8_t                      Type;   /**< Collection type (e.g. "Generic Desktop"). */
 182                                 HID_Usage_t                  Usage;  /**< Collection usage. */
 183                                 struct CollectionPath*       Parent; /**< Reference to parent collection, or NULL if root collection. */
 184                         } HID_CollectionPath_t;
 185
 186                         /** Type define for all the data attributes of a report item, except flags. */
 187                         typedef struct
 188                         {
 189                                 uint8_t                      BitSize;  /**< Size in bits of the report item's data. */
 190
 191                                 HID_Usage_t                  Usage;    /**< Usage of the report item. */
 192                                 HID_Unit_t                   Unit;     /**< Unit type and exponent of the report item. */
 193                                 HID_MinMax_t                 Logical;  /**< Logical minimum and maximum of the report item. */
 194                                 HID_MinMax_t                 Physical; /**< Physical minimum and maximum of the report item. */
 195                         } HID_ReportItem_Attributes_t;
 196
 197                         /** Type define for a report item (IN, OUT or FEATURE) attributes and other details. */
 198                         typedef struct
 199                         {
 200                                 uint16_t                     BitOffset;      /**< Bit offset in the IN, OUT or FEATURE report of the item. */
 201                                 uint8_t                      ItemType;       /**< Report item type, a value in HID_ReportItemTypes_t. */
 202                                 uint16_t                     ItemFlags;      /**< Item data flags, such as constant/variable, etc. */
 203                                 uint8_t                      ReportID;       /**< Report ID this item belongs to, or 0x00 if device has only one report */
 204                                 HID_CollectionPath_t*        CollectionPath; /**< Collection path of the item. */
 205
 206                                 HID_ReportItem_Attributes_t  Attributes;     /**< Report item attributes. */
 207
 208                                 uint32_t                     Value;          /**< Current value of the report item - use \ref HID_ALIGN_DATA() when processing
 209                                                                               *   a retrieved value so that it is aligned to a specific type.
 210                                                                               */
 211                                 uint32_t                     PreviousValue;  /**< Previous value of the report item. */
 212                         } HID_ReportItem_t;
 213
 214                         /** Type define for a report item size information structure */
 215                         typedef struct
 216                         {
 217                                 uint8_t                      ReportID; /** Report ID of the report within the HID interface */
 218                                 uint8_t                      ReportSizeBits[3]; /** Total number of bits in each report type for the given Report ID,
 219                                                                                  *  indexed by the \ref HID_ReportItemTypes_t enum
 220                                                                                                                                  */
 221                         } HID_ReportSizeInfo_t;
 222
 223                         /** Type define for a complete processed HID report, including all report item data and collections. */
 224                         typedef struct
 225                         {
 226                                 uint8_t                      TotalReportItems; /**< Total number of report items stored in the
 227                                                                                 *   ReportItems array.
 228                                                                                 */
 229                                 HID_ReportItem_t             ReportItems[HID_MAX_REPORTITEMS]; /**< Report items array, including
 230                                                                                             *   all IN, OUT and FEATURE items.
 231                                                                                                 */
 232                                 HID_CollectionPath_t         CollectionPaths[HID_MAX_COLLECTIONS]; /**< All collection items, referenced
 233                                                                                                     *   by the report items.
 234                                                                                                     */
 235                                 uint8_t                      TotalDeviceReports; /**< Number of reports within the HID interface */
 236                                 HID_ReportSizeInfo_t         ReportIDSizes[HID_MAX_REPORT_IDS]; /**< Report sizes for each report in the interface */
 237                                 uint16_t                     LargestReportSizeBits; /**< Largest report that the attached device will generate, in bits */
 238                                 bool                         UsingReportIDs; /**< Indicates if the device has at least one REPORT ID
 239                                                                               *   element in its HID report descriptor.
 240                                                                               */
 241                         } HID_ReportInfo_t;
 242
 243                 /* Function Prototypes: */
 244                         /** Function to process a given HID report returned from an attached device, and store it into a given
 245                          *  \ref HID_ReportInfo_t structure.
 246                          *
 247                          *  \param[in] ReportData  Buffer containing the device's HID report table
 248                          *  \param[in] ReportSize  Size in bytes of the HID report table
 249                          *  \param[out] ParserData  Pointer to a \ref HID_ReportInfo_t instance for the parser output
 250                          *
 251                          *  \return A value in the \ref HID_Parse_ErrorCodes_t enum
 252                          */
 253                         uint8_t USB_ProcessHIDReport(const uint8_t* ReportData, uint16_t ReportSize, HID_ReportInfo_t* const ParserData)
 254                                                      ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(3);
 255
 256                         /** Extracts the given report item's value out of the given HID report and places it into the Value
 257                          *  member of the report item's \ref HID_ReportItem_t structure.
 258                          *
 259                          *  When called, this copies the report item's Value element to it's PreviousValue element for easy
 260                          *  checking to see if an item's value has changed before processing a report.
 261                          *
 262                          *  \param[in] ReportData  Buffer containing an IN or FEATURE report from an attached device
 263                          *  \param[in,out] ReportItem  Pointer to the report item of interest in a \ref HID_ReportInfo_t ReportItem array
 264                          *
 265                          *  \returns Boolean true if the item to retrieve was located in the given report, false otherwise
 266                          */
 267                         bool USB_GetHIDReportItemInfo(const uint8_t* ReportData, HID_ReportItem_t* const ReportItem)
 268                                                       ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 269
 270                         /** Retrieves the given report item's value out of the Value member of the report item's
 271                          *  \ref HID_ReportItem_t structure and places it into the correct position in the HID report
 272                          *  buffer. The report buffer is assumed to have the appropriate bits cleared before calling
 273                          *  this function (i.e., the buffer should be explicitly cleared before report values are added).
 274                          *
 275                          *  When called, this copies the report item's Value element to it's PreviousValue element for easy
 276                          *  checking to see if an item's value has changed before sending a report.
 277                          *
 278                          *  If the device has multiple HID reports, the first byte in the report is set to the report ID of the given item.
 279                          *
 280                          *  \param[out] ReportData  Buffer holding the current OUT or FEATURE report data
 281                          *  \param[in] ReportItem  Pointer to the report item of interest in a \ref HID_ReportInfo_t ReportItem array
 282                          */
 283                         void USB_SetHIDReportItemInfo(uint8_t* ReportData, HID_ReportItem_t* const ReportItem)
 284                                                       ATTR_NON_NULL_PTR_ARG(1) ATTR_NON_NULL_PTR_ARG(2);
 285
 286                         /** Retrieves the size of a given HID report in bytes from it's Report ID.
 287                          *
 288                          *  \param[in] ParserData  Pointer to a \ref HID_ReportInfo_t instance containing the parser output
 289                          *  \param[in] ReportID  Report ID of the report whose size is to be retrieved
 290                          *  \param[in] ReportType  Type of the report whose size is to be determined, a valued from the
 291                          *                         \ref HID_ReportItemTypes_t enum
 292                          *
 293                          *  \return Size of the report in bytes, or 0 if the report does not exist
 294                          */
 295                         uint16_t USB_GetHIDReportSize(HID_ReportInfo_t* const ParserData, const uint8_t ReportID,
 296                                                       const uint8_t ReportType) ATTR_CONST ATTR_NON_NULL_PTR_ARG(1);
 297
 298                         /** Callback routine for the HID Report Parser. This callback <b>must</b> be implemented by the user code when
 299                          *  the parser is used, to determine what report IN, OUT and FEATURE item's information is stored into the user
 300                          *  HID_ReportInfo_t structure. This can be used to filter only those items the application will be using, so that
 301                          *  no RAM is wasted storing the attributes for report items which will never be referenced by the application.
 302                          *
 303                          *  \param[in] CurrentItem  Pointer to the current report item for user checking
 304                          *
 305                          *  \return Boolean true if the item should be stored into the HID_ReportInfo_t structure, false if it should be ignored
 306                          */
 307                         bool CALLBACK_HIDParser_FilterHIDReportItem(HID_ReportItem_t* CurrentItem);
 308
 309         /* Private Interface - For use in library only: */
 310         #if !defined(__DOXYGEN__)
 311                 /* Type Defines: */
 312                         typedef struct
 313                         {
 314                                  HID_ReportItem_Attributes_t Attributes;
 315                                  uint8_t                     ReportCount;
 316                                  uint8_t                     ReportID;
 317                         } HID_StateTable_t;
 318         #endif
 319
 320         /* Disable C linkage for C++ Compilers: */
 321                 #if defined(__cplusplus)
 322                         }
 323                 #endif
 324
 325 #endif
 326
 327 /** @} */